# Taking a great idea and applying modern techniques



## anachronism

For a few months now people have been asking me how I've applied Dean's electrowin cell to refining. Following calls and emails with senior members and moderators, I thought it would be good to throw out there some of the work that's being done.

Whilst the concept and chemistry that Dean so kindly shared with the members is a given, only the practical presentation and structural design can really be improved utilising current technology. The end goal being a cell that anyone can use. Repeatedly, and with a minimum of consumables. I would strongly recommend that anybody who has not read Dean's missives does so post haste. Why? Because the information held in these is revolutionary in terms of bringing processes both up to the modern age, and allowing a home refiner to process product that he/she would have originally thought beyond their reach.

For those who have yet to read the thread written by Deano, you can find it here http://www.goldrefiningforum.com/phpBB3/viewtopic.php?f=37&t=21526

The design, prototyping, materials technology, equipment, and engineering to do this is costly both financially and in sheer time however I hope members will agree that it's a worthwhile exercise.

The pics below detail some of the basic interior cathode carriers. Moving the cathode closer to the anode reduces the [stt]current[/stt] voltage (see posts below) required to operate the cell efficiently thereby allowing more than one cell to operate on one power supply. Allowance has to be made for the cathode increasing in thickness whilst making changing it quickly and efficiently a priority. 

The print shown in process is using a rough detail and ABS. The actual material used will be different. I'd welcome any comments or questions that anyone may have. 

Jon


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## goldsilverpro

> Moving the cathode closer to the anode reduces the current required to operate the cell efficiently thereby allowing more than one cell to operate on one power supply.


I must admit that I have not read Deano's threads. I will, since your post has interested me in them. In the meantime, let me comment on your above statement.

Moving the electrodes closer together will lower the resistance between them and will thus require less voltage for the same amount of current. The amount of metal deposited is directly proportional to the current applied to the cathode. In your statement, if you reduced the current, you would plate less metal. I can't see how you would gain by reducing the current.

Hypothetically, let's say you have a cell with a 12" spacing between the electrodes. Let's say you are plating 100A @ 6V, using a 100A, 9V rectifier. You decide to move the electrodes closer, to 3" apart. At the same 100A, you are now only using 3V, let's say. Therefore, using the same rectifier, you are now able to add 2 more identical cells,* in series*. Each cell will run 100A at 3V. The rectifier will read 100A and 9V. This will triple your production using the same power supply. In a series circuit, the amperage is constant and the voltage is additive.


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## anachronism

Chris you're correct but there is one factor that needs to be considered. 

You're using carbon felt as a cathode with a surface area exponentially greater than any other cathode.


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## g_axelsson

That's ingenious to 3d-print the electrode apartment. I really like it!  

Chris is correct in that the distance between electrodes affects the voltage in the cell, not the current efficiency. That is a fundamental concept of electrolytic cells.
The cell voltage depends on a number of factors, the chemical reaction at the electrodes (practically a fixed voltage depending on the chemistry), electrode polarization (heavily depending on electrode area, concentration of chemicals, current density, temperature and convection) and electrolyte resistance (depending on electrode distance and concentration of ions in the electrolyte). 

Current efficiency is defined as the amount of metal produced compared to the theoretical maximum and can as most be 100 percent. Losses comes from side reactions, for example splitting water into oxygen and hydrogen but also from other reactions driven by the current at the electrodes.
https://en.wikipedia.org/wiki/Faraday_efficiency

Power efficiency on the other hand is increased with lower electrode distance as the voltage drops and the cell uses less wattage of power.

Where do you find the carbon felt that you are using for the electrode?

Thanks for sharing! Looking forward to the rest of this thread.

Göran


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## nickvc

Jon I know you have been working hard on using Deano,s teachings and it's good to see the proof of concept and the effort of all your hard work and study, I have seen other versions of the same concept that were very very expensive but worked really well on stripping all metals from acidic and base solutions. 
With the environmental controls now in place all over the modern world many industries need to strip waste solutions before discharge meets the rules, from the tests I saw the discharged waste was cleaner than the water ways it was going into including harmful metals, as for refining if members can grasp the science behimd this and adapt it to their needs and processes it really can be a game changer from recovering values to stripping waste solutions making disposal very easy and legal.
As you have suggested and I have already posted about read and understand Deano,s posts they contain some real gems of knowledge which can be applied to most members processing.


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## anachronism

Chris/Goran

Yes I got my terminology completely incorrect regarding the current. Closing the distance between the anode and cathode lowers the voltage required to draw enough current to deposit the metal. Effectively lowering the wattage and running cost of the cell. 

Something to bear in mind on this cell is that an over current is required to keep the deposition rate above the loss rate otherwise you can end up in a situation whereby have an equilibrium where metal is being lost to the liquor as fast as it is being deposited. The current required to deposit depends upon the tenor of the liquor. Now the challenge in building this for a home user is as follows:

The ideal situation is to run the cell in conjunction with an AA. The liquor would be sampled at point of entry and point of return (after passing through the cathode) to ensure that the current is high enough, and removing gold from your solution. This isn't ideal for a home user since the cost of an AA is likely to be prohibitive. As such the cell needs to be robust enough to run at a relatively high over current to ensure your metals are being deposited without the need to check the tenor of the solution using an AA. 

Then again, running it far too high would shred your anode quicker than normal, so again you need to weigh up the cost/benefit of either using high grade carbon or low grade carbon for the anode or even using a platinised Titanium anode. 

These are considerations that have required investigating and the respective options are undergoing test. It's all about trade offs because for each benefit there is a cost somewhere else in the system. Determining the healthy balance is the challenge. 

Jon


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## anachronism

Concept print of the internals. Printed in low detail high speed in cheap material to produce a physical model of the unit whilst allowing improvement and development. 

Even whilst this was printing a further 8 design alterations were being made. There's a lot to do to ensure correct fluid flow and ease of use. The cell is scale-able- this is a miniature one.


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## 4metals

The circle around the base is where a plastic pipe is attached to form the liquid holding reservoir? The carbon felt you use comes in square sheets, is the slot on the outer circle where the ends of the sheet start and end up to assure all liquid has to pass through the felt fabric? Very nice design so far. 

I think a re-posting of the image you had posted in a previous thread of your original system before you started with the 3 D printed version would be helpful to show where this is all leading, albeit in a more efficient improved version.


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## 4metals

> The ideal situation is to run the cell in conjunction with an AA.



What are the ranges of gold concentration you expect to see before passing through the cell in grams per liter? The reason I ask is there is an analytical method using concentrated sulfuric acid added to the solution, which is carried out in a properly exhausted lab hood, that has been used for years to analyze gold cyanide plating solutions gravimetrically. If the concentrations are sufficient for detection, it is possible an AA is not necessary for a small shop. This could go a long way into opening up this methodology to smaller refining operations.


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## anachronism

4metals said:


> The circle around the base is where a plastic pipe is attached to form the liquid holding reservoir? The carbon felt you use comes in square sheets, is the slot on the outer circle where the ends of the sheet start and end up to assure all liquid has to pass through the felt fabric? Very nice design so far.
> 
> Yes and yes. That's completely correct.
> 
> I think a re-posting of the image you had posted in a previous thread of your original system before you started with the 3 D printed version would be helpful to show where this is all leading, albeit in a more efficient improved version.



Thanks 4 metals, certainly please see below. This was made using standard readily available items for the hardware, and fabricated with plastic welding. The proof of concept worked well.


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## anachronism

4metals said:


> The ideal situation is to run the cell in conjunction with an AA.
> 
> 
> 
> 
> What are the ranges of gold concentration you expect to see before passing through the cell in grams per liter? The reason I ask is there is an analytical method using concentrated sulfuric acid added to the solution, which is carried out in a properly exhausted lab hood, that has been used for years to analyze gold cyanide plating solutions gravimetrically. If the concentrations are sufficient for detection, it is possible an AA is not necessary for a small shop. This could go a long way into opening up this methodology to smaller refining operations.
Click to expand...


You're running the cell with the express aim of operating a recirculating leach. i.e. The leach liquor is drawn out of the leach tank and fed into the cell where it is stripped of metals before being passed back into the leach tank. 

Given that a leach such as any derivative of CN- loads best at low tenors the concept is that this cell keeps the tenors low constantly, thereby allowing the user to strip at maximum capacity using the minimum of CN-. In non technobabble, the less metal in your leach solution, the faster it strips gold and that's where you want to keep it. As such you do not want grammes per litre concentrations of gold flowing around the circuit. 

You therefore need to know that the liquor coming back into the leach has less gold in it than the liquor going into the cell. Can I ask if that method you mentioned would enable that information to be obtained?

Edits for context and spelling.


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## nickvc

With very low loaded solutions I do not think the method 4metals alluded to would work as the amount of gold would be almost negligible if the system is working correctly, I stand to be corrected by the experts in this view because if it is indeed possible, as 4metals said, it could be a game changer for many.


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## anachronism

That opens up a great discussion point Nick. Do you think our resident professionals could help us with a non AA method of determining a quantifiable difference in gold loading between solutions? 

Yes you could probably do it with Stannous Chloride by seeing how dark the solution goes but is there another way? As you say it would open a lot of doors.


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## 4metals

Thanks for posting the photo, it makes it easier to envision the entire process. Is the peristaltic on the left of the photo bringing in loaded solution? And the overflow above it where untreated solution returns to the reservoir? This would assure the outer layer of solution is always full and the flow through flow rate (ie. how many liters per hour you process) is determined by the flow rate of the peristaltic pump on the right. 

I have to look up the analytical method for gold cyanide solutions but it clearly will drop all of the gold so it can be collected and weighed. Trouble is if you were to be running around 1 gram/liter, the standard sample size would require you to be weighing about 25 milligrams which may be too little to do accurately. It is possible to increase the sample size to increase the metal you weigh at the end but before we go that route, do you think you ever approach 1 g/l? 

When I get back to my book collection I will look up and post the method.


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## anachronism

The photo with the pump on the left. This was actually altered so that the inflow pump was fitted to the top pipe, making the lower left hand pipe the overflow back to the tank. Otherwise you could have been in a situation where you had a head of excess fluid in the even of needing to change the pump. 

Yes as you stated the theory is that you always have a constant full level in the cell which is replenishing, so even if your cell fails/or the outlet pump fails you cannot overflow.


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## 4metals

Gold strike solutions run 0.5 to 1.5 g/l and they are analyzed successfully with this method. 

Note of caution; This method requires acidification of cyanide solutions with concentrated sulfuric acid. It must be done in a good fume hood. This is not the type of warning you want to blow off. 

Sample size 20 ml

Add 25 ml of concentrated H2SO4 to the sample and heat to the evolution of white fumes.
Cool the solution and add 10 ml of 30 percent H2O2 and heat to evolution of white fumes.
Continue the additions of H2O2 and heating until the gold coagulates and the solution clears.
Add 100 ml of H2O and heat to 140º F for 5 minutes
Filter through a tared Gooch filter and dry in a 110º C oven. Cool in a dessicator and weigh the gold.


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## 4metals

So with the inflow into the center section and the overflow high enough to maintain a fill level, you only need 1 peristaltic pump?


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## anachronism

4metals said:


> So with the inflow into the center section and the overflow high enough to maintain a fill level, you only need 1 peristaltic pump?



On the input side yes. One on the output side is required to draw the stripped liquor out and return to the leach tank. As an improvement the new cell is optionally able to be gravity fed from a header tank using a valve to control the flow. Less components to buy and fit, and given the built in self levelling system that pump therefore becomes redundant. 

This is an important modification because larger systems will require multiple cells operating in parallel.


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## 4metals

I have always found that having 2 pumps paired up to fill and drain a system in tandem eventually results in either a dry tank or a flood because it is impossible to get them flowing exactly at the flow you want. I would be flowing out with gravity to a sump below so only one pump controlled the cell levels and flow rate. I learned these lessons the hard way, fortunately with aquariums (not fortunately if you happened to be a fish!) rather than with chemicals holding values. But the same basic laws of plumbing still apply. 

I also understand the value of a header tank but question why the cell cannot be sized to recover the volume of leachate in a timely manner, say overnight, and come morning you will have recovered the entire batch. If you are doing an entire field of mining ore I can see needing extra cells, but for e-scrap where you have to pay each customer it is nice to know you have all of the value from one batch in a single cell. 

You say the goal is to strip the values in a single pass but do you send the stripped solution back to strip more values or is there a replenishment step to adjust the CN-concentration?


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## anachronism

You can't have the outflow using gravity, because the outflow is what is actually controlling the speed of the liquor through the cathode. You use the inflow to create a reservoir of pregnant liquor outside the cathode layer and the outflow draws the liquor through it. It's this flow that is varied depending on the leach liquor and whether the required stripping is being achieved. 

You have two self regulating reservoirs- the one that is the header tank and the one around the cathode. A simple switch that works on current detection will turn the cell off if it runs dry. 

The header tank has two purposes- the one you have mentioned, but also to feed liquor from its overflow back into the leach tank and plunge it into the solution thereby aerating it. There's no oxidant required in the set up, as this constant flow provides all the oxygen required. 

To answer your question as to why the cell cannot be resized to utilise a faster flow and thereby larger volumes. The simple answer is that it can.  

You are not necessarily looking to single pass strip everything, you are looking to strip enough of the metals to keep the tenor low enough to stay operating at peak leach rates. This liquor is passed back into the leach tank to replenish the load. You can monitor the effectiveness of the leach and top up your preferred reagent as required. Once your batch is stripped completely then flow rates will be adjusted to single pass strip everything, and a valve can divert the completely stripped solution to another holding tank for either storage or destruction by passing through the cell with reversed polarity.


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## 4metals

OK, I misunderstood when you said,


> This was actually altered so that the inflow pump was fitted to the top pipe, making the lower left hand pipe the overflow back to the tank.



I thought you meant the top pipe as in the top of the inner section. So the inflow and return of unprocessed solution are both on the outside pipe section not the inside. And by keeping that full of gold containing solution, more solution is drawn through the carbon felt proportional to the quantity of liquid pumped out from inside the carbon felt. Is there any significant flow restriction from the density of the felt fabric? Or does more flow restriction develop as the felt loads up with metal? 

I am familiar with the copper expanded mesh cathodes where there is never enough flow restriction to be an issue but, as you pointed out, the surface area of the copper mesh is significantly less than that of the carbon felt.



> You have two self regulating reservoirs- the one that is the header tank and the one around the cathode. A simple switch that works on current detection will turn the cell off if it runs dry.



So the outside reservoir, which you are calling a header tank has a feed pump and an overflow and it maintains level as long as the pump functions. The other reservoir which you call the one around the cathode can run dry if the flow through the cathode carbon felt is less than the flow rate of the inner peristaltic pump or if the pump filling the header tank craps out and the inner pump sucks the reservoir dry. So I guess it can slow significantly by clogging with deposited metal. Damn gold clogging things up! Either way if the cell goes dry it shuts down, nice.


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## anachronism

4metals said:


> I thought you meant the top pipe as in the top of the inner section. So the inflow and return of unprocessed solution are both on the outside pipe section not the inside. And by keeping that full of gold containing solution, more solution is drawn through the carbon felt proportional to the quantity of liquid pumped out from inside the carbon felt. Is there any significant flow restriction from the density of the felt fabric? Or does more flow restriction develop as the felt loads up with metal?
> 
> Flow restriction isn't initially a factor as you would be drawing from as little as a litre per hour up to 2 litres per hour through the cell at this size. In larger cells with more flow rate, you have an increase in cathode surface area albeit not necessarily in direct proportion. Yes as metal is deposited on the carbon the flow rate will diminish and that is one of the key indicators as to how close your carbon is to becoming fully loaded because it would in time end up completely clogged. Now that is a good place to be simply because due to the enormous surface area the sheer amount of gold you can fit on even a small cathode before clogging it is way more than the average home user is likely to be processing. Put it this way- 50g is hardly even visible as much more than a discolouration. So for the smaller batch guy flow rate won't present an issue.
> 
> I am familiar with the copper expanded mesh cathodes where there is never enough flow restriction to be an issue but, as you pointed out, the surface area of the copper mesh is significantly less than that of the carbon felt. Yes the difference in surface area is enormous.
> 
> 
> 
> 
> You have two self regulating reservoirs- the one that is the header tank and the one around the cathode. A simple switch that works on current detection will turn the cell off if it runs dry.
> 
> 
> 
> 
> So the outside reservoir, which you are calling a header tank has a feed pump and an overflow and it maintains level as long as the pump functions.
> 
> Entirely correct.
> 
> The other reservoir which you call the one around the cathode can run dry if the flow through the cathode carbon felt is less than the flow rate of the inner peristaltic pump or if the pump filling the header tank craps out and the inner pump sucks the reservoir dry.
> 
> Not quite. The reservoir around the exterior of the cathode is not dependant upon the outflow from the return pump that's between the cathode and anode unless the feed from the header tank ceases.
> 
> So I guess it can slow significantly by clogging with deposited metal. Damn gold clogging things up!  True and see above. Either way if the cell goes dry it shuts down, nice.
Click to expand...


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## nickvc

I have to say well covered and answered Jon, if the members follow this thread with input from our experts then they can learn a lot, but they need to fully understand what is been discussed and the science behind it.


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## 4metals

The real appeal is what hasn't really been discussed on this thread. That is the low concentrations (in PPM) of cyanide required to strip the gold. Maintaining lower levels of cyanide leaves the majority of the copper on the scrap but collects the gold and silver. 

This is not really refining and it isn't even the material preparation before leaching, but it is a major step forward which combined with the material preparation and the post cell ashing and acid refining, can go a long way in processing e-scrap and make previously unprofitable operations turn the corner with a process that is both scalable and relatively straightforward. 

This cell deserves the attention of all those who recover gold and silver from e-scrap.


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## 4metals

Any new progress on the build? I would hate to see this thread dry up and be forgotten, this process has the potential to put a lot of the other e-scrap methods into the old and forgotten files. 

Surely there must be some interest out there!!!!!


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## anachronism

The update from my end is as follows 4metals:

We've received the final material that we selected for the print because of the chemical resistance and overall balance between flexibility and rigidity. It's a material which isn't as widely used as others yet so there has been a lot of experimentation with regards to print temperatures and base sheet material to avoid deformation and de-lamination. That's now sorted out and the picture below shows some of the new material in it's correct dimensions although merely half a print. It's still a rough print at this stage but we should be moving towards final prints this weekend, rolling into early next week.

The plan is to have 2 working cells for the Christmas break to fully trial using the leach system which is also in fabrication.


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## 4metals

Thanks for the update. With the cell you are printing, what is the area of the fabric that will be exposed to the leach solution. I know the actual surface area is exponentially higher than the physical piece of felt you use, but what size piece of felt will this accommodate? And what volume of solution will the entire cell contain when operating? 


Sent from my iPhone using Tapatalk


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## Lou

Looks a lot to me like a carbon version of that gold bug system.

I always used steel wool to do this process, not carbon felt.

Where do you get the felt state side and what is the solution concentration you operate at (before/after the felt, in g/L CN- and Au)?


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## rickbb

Appears to be 2 kinds of carbon felt, PAN and Rayon. Amazon lists lots of PAN carbon felt for use as a welding or soldering heat shielding blanket. The specs for it say it's not a good conductor of current, so I'm guessing that Rayon is?

https://www.amazon.com/HIGH-TEMP-FELT-WELDING-BLANKET/dp/B00S1R9B22/ref=sr_1_5?ie=UTF8&qid=1481907237&sr=8-5&keywords=carbon+felt

"However, please note it is not electrically conductive."

More info and sources here;

http://ceramaterials.com/graphitecarbonfelt.html

http://www.hpmsgraphite.com/activatedcarbonfiber.html


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## anachronism

You are not using activated carbon of any type in this cell Rick. Having said that your other link is great- thanks for that.


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## anachronism

4metals said:


> Thanks for the update. With the cell you are printing, what is the area of the fabric that will be exposed to the leach solution. I know the actual surface area is exponentially higher than the physical piece of felt you use, but what size piece of felt will this accommodate? And what volume of solution will the entire cell contain when operating?
> 
> For the smaller cell approx 140 sq cm of cathode, and as mentioned before this scales depending upon the height of the cell used. Volume of liquid approx 310 cubic cm in this version.
> 
> 
> Sent from my iPhone using Tapatalk


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## anachronism

Lou said:


> Looks a lot to me like a carbon version of that gold bug system.
> 
> I'd not looked at that before Lou and even from a brief scan of the documents there are certainly some similarities in function if not construction and design.
> 
> I always used steel wool to do this process, not carbon felt.
> 
> Yeah we've touched on this before - the sheer surface area if the major difference coupled with the inert carbon vs steel in the metal deposited.
> 
> Where do you get the felt state side and what is the solution concentration you operate at (before/after the felt, in g/L CN- and Au)?
> 
> Stateside I would not have had a clue until Rick kindly posted a link.  The premise of the cell is to attach to a leach circuit where the leach is low strength and kept at low tenors by the stripping action of the cell. Sub .5g per litre gold prior to cathode and substantially less per litre afterwards for the return into the leach tank to keep the average circuit load as low as possible.
> 
> Cyanide strengths depend on the type of product being leached, the speed of leach required, and the contaminants present in the raw material. So your range of strengths would begin at as low as 0.05g per litre and progress upwards.


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## 4metals

Wow, that i s less than 22 square inches of fabric and 11 fluid ounces of strip in the cell. (I converted these numbers to help those of us who live in countries that do not recognize the wisdom of the metric system) 

That is one pint sized (literally) cell. From the lack of response to this thread from others, I can only assume they do not recognize the amazing potential of this system for a small time collector. 

So let's do an imaginary refine so members can get a feel for the versatility of this system as well as the investment in space for the setup. 

If we were to start simple, say with gold plated pins. Like sulfuric stripping is used for by many members as a mechanism to get the gold and leave behind the base metals. So a leach tank for, lets say, a 4 liter beaker filled with gold plated pins. What size leaching system would be required to strip and hold the gold in solution. I am guessing a 5 gallon (20 liter) bucket? What concentration of CN-would be required to strip this metal? And how long from start to finish for the leach?

So with an investment of X grams of Cyanide and Y hours of time stripping, the material is ready for stripping in the 3D printed cell. How long will it take to completely strip the solution of gold in the cell?

I happen to know the answers to these questions but I am trying to put this into a perspective where our members can see the value of this system and start asking some questions and maybe see the true potential of this system. I am sure some are put off by the fact that the majority of the stripping is done by cyanide. But there are alternatives that are legal and the treatment of the parts per million levels of cyanide you will encounter when you eventually discard your leach is likely easier than treatment of acid wastes. 

And this cell can help in the treatment of waste too! The versatility of this system can have serious implications on refining. The fact that many of our members have yet to realize its value has me scratching my already hairless head!


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## anachronism

4metals said:


> So with an investment of X grams of Cyanide and Y hours of time stripping, the material is ready for stripping in the 3D printed cell. How long will it take to completely strip the solution of gold in the cell?
> 
> I've pulled this particular question out as it merits an explanation as to the workings of the system for clarity. You are not going to be waiting Y hours to begin stripping the gold into the cell. _You are going to be stripping through the cell right from the get go_, and continuously throughout the leach process. How long it takes to fully strip the gold from the leach circuit on completion of the leach depends upon the volume of liquid in the circuit and the chosen rate of flow through the cell. As an example at 1 litre per hour you can completely strip a 20 litre circuit in 20 hours. With the analogy you used for a pile of pins I believe (but have yet to prove via a working model,) you could theoretically have a full circuit of less than 8 litres.
> 
> And this cell can help in the treatment of waste too! The versatility of this system can have serious implications on refining. The fact that many of our members have yet to realize its value has me scratching my already hairless head!
> 
> Reverse the polarity of the cell by literally flipping a switch, pop a fresh cathode in and you'll be able to destroy your CN bearing waste solution at a rate of 1 litre per hour in this little cell. Obviously the cell scales, so take this as a mere starting point.


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## FrugalRefiner

4metals said:


> From the lack of response to this thread from others, I can only assume they do not recognize the amazing potential of this system for a small time collector.
> 
> The fact that many of our members have yet to realize its value has me scratching my already hairless head!


I can only speak for myself, but I don't deal with much escrap or other gold plated material. While the idea of cyanide stripping of plated material is interesting, and I may experiment with it at some time in the future, I will probably never deal with quantities that would justify the time and expense to create CAD drawings, buy a 3D printer, experiment with different kinds of plastics, etc. If I decided to experiment with a cell like this, it would be a frugal version as described by Deano similar to the one Jon made first. If I wanted a more durable version I might spend a few hours drilling some carefully placed holes in some PVC pipe. I'm not trying to take anything away from Jon's work. It's just beyond my needs.

Another factor that may be keeping the thread from getting many responses is that until very recently, the use of cyanide has been discouraged on the forum. Obviously the professional refiners here have used it, but I would guess the vast majority of our members have never touched the stuff. Even in the Eco-Goldex thread, we've cautioned members to wait until there are some comprehensive threads created on the subject. Those threads have been mentioned, but they still don't exist.

So I don't know that members don't recognize the potential or realize its value, but I would guess it is likely beyond the needs or means of most members at this time.

Dave


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## 4metals

When this type of cell is running, the cyanide concentrations are very low and the recovery is excellent for stripping gold from pins headers or any exposed gold. But it doesn't end there, if it can be leached it can be concentrated in this type cell. Think silver plated flatware, think film, anything you can strip off chemically, you can process in this to concentrate your values on the carbon felt. From there on out, it is just a roast and acid refining. 

That is why I think this warrants a discussion, and even your explanation of why it isn't for you Dave helps to explain some of the benefits and can help allay some of the fears members may have in dealing with this technology. If a full blown discussion can evolve here there are a lot of members who can realize its potential. But if we don't discuss it it will be just another lost pearl buried in pages of babble that most will miss out on.


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## FrugalRefiner

4metals, I wasn't trying to discourage discussion. I apologize if the intent of my post wasn't clear. You commented about wondering why the thread wasn't getting more responses. I simply responded to that by giving my opinion as to why that might be.

I'll be happy to see cyanide discussed. I've encouraged it in the past. If I could write a comprehensive thread on the subject, I'd do so, but I have never used it so it is beyond my experience.

Dave


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## nickvc

I feel that perhaps when the prototypes are ready then a video showing how to use it with different materials and solutions may well get more conversation going, this to many is a new process, I posted about the same cell some years ago but that was prohibitively expensive for general use, as 4merals has pointed out this can strip all metals from solution so using it for waste treatment will make disposal safe and easy, this is a brilliant idea that Jon is trying show to all the members, it's now up to the members to see its potential and ask the questions which will show how many could benefit from its use.


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## Yggdrasil

Hi!
The cell caught my interest the moment Deano informed about it.

It's use seem to be mostly "limited by imagination" though especially well suited for constant/long lasting leeching which benefits from low concentrations of leech liquor and/or dissolved metals.
My reluctance to comment so far has been that I haven't come to a point where I have accumulated any information to share :wink: In fact my graphite electrode disappeared on route from Beijing to Europe and my felt has just arrived in town. 
I do not have access to a 3D printer as Jon has so my initial construction will not be as nice as his. 

*Kudos to Jon for pushing his research forward and sharing  * :!: :!: 

But I think it is fully possible to design a system that is only dependent of one pump and is scalable to multiple cells.
If gravity fed from the leech system with a adjustable valve into the outer chamber with overflow as current design to a collector tank. A new gravitation fed system from the inner cell with its own adjustable valve into same collector tank. Then the only pump you need is a pump to re introduce the leech liquor back to the system.
Obviously the pump must have sufficient capacity to do so. Additionally with this design one can have backups and aeration or what ever treatment one feels suitable to the leech system prior to pumping it back.

Please correct me if I there are issues that I have overlooked.

Lets get some drive to further evolve this promising technology  :lol:


----------



## kurtak

4metals said:


> That is one pint sized (literally) cell. From the lack of response to this thread from others, I can only assume they do not recognize the amazing potential of this system for a small time collector.



I can't speak for anyone else BUT I certainly recognize the potential of this system - I simply have not responded (posted) because right now I am reading & hanging on "every word" to soak up the "awesome" info being presented by those of you taking center stage to present this thread with such fine & great detail :!: :!: :!: 

This thread is :G :G :G IMO 8)  



> And this cell can help in the treatment of waste too! The versatility of this system can have serious implications on refining. The fact that many of our members have yet to realize its value has me scratching my already hairless head!



I agree - & per the underlined - I resemble that remark :lol: (told you I was hanging on every word) :mrgreen: 

Kurt


----------



## g_axelsson

Just like Kurt I haven't responded since I don't have any experience with cyanide yet. But I'm reading every post and hope I will have the opportunity to build my own cell soon.

For those without access to a 3D-printer, there are many "fab-labs", "maker spaces" or "hacker spaces" where the general public is welcome to learn and use this type of equipment.

Any tips on where to find a suitable carbon felt for Europeans?

Göran


----------



## nickvc

One point I didn't stress is that this cell is not just for use in cyanide processes but with any solution containing metals, precious or otherwise and it has the advantage of making the solutions to a certain extent reusable this cutting down on waste and costs.


----------



## kurtak

Lou said:


> Looks a lot to me like a carbon version of that gold bug system.
> 
> I always used steel wool to do this process, not carbon felt.
> 
> Where do you get the felt state side and what is the solution concentration you operate at (before/after the felt, in g/L CN- and Au)?



Lou

per the underlined - In another thread you had posted that & then said you used sulfuric to dissolve away the steel (iron) --- I "assume" you are doing this with a flow through cell as well such as the cell being discussed here

I ask because I am about to make my first venture into CN leaching which means my recovery options (once I have my gold in solution) are zinc cementing, carbon loading (CIL) or electro winning & as best as I can tell the electro winning is the better of the three options

However - I don't currently have everything I need to set up the "flow though" cell - so between time to order needed components (& wait the arrival) & then time to build the flow through cell it puts the flow through cell out of question for the current batch of pins I will be doing

So - my real question is - can I run the cell (winning) without the need for solution to flow through the cathode - in other words a simple tank to hold the solution with an inert anode (high density carbon) & cathode(s) for the gold to plate to ?

If so - then my question is what would be my best option for my cathode(s) - I have the "high" density carbon for my anode - but - for the cathode(s) would the steel wool still be a good option - or could carbon be used for both anode & cathode - or a titanium plate (I have one) or sheet(s) of SS

Edit to add; - I know you can set up a winning cell as a simple tank (no flow through) with acidic solution such as copper nitrate - just not sure if &/or how well it would work with a CN (alkali) solution 

Kurt


----------



## kurtak

nickvc said:


> One point I didn't stress is that this cell is not just for use in cyanide processes but with any solution containing metals, precious or otherwise and it has the advantage of making the solutions to a certain extent reusable this cutting down on waste and costs.



You beat me to it Nick - that was going to be my next post :mrgreen: 

This cell is actually ideal for those that have a hard time &/or have to pay a high price for their nitric

It would allow them to use nitric for processing silver - cement the silver with copper - then win the copper back - & "reuse" the nitric for the next batch of silver

My point being that a lot of members don't do silver because they have to pay such a high price for very small amounts of nitric - so they reserve there nitric for AR &/or don't use nitric at all (so don't do silver) & instead go with poor mans AR &/or HCl/Cl to do their gold

This cell could get them in the game with silver as they would be able to reuse that high price nitric multiple times

Kurt


----------



## anachronism

Yggdrasil said:


> Hi!
> The cell caught my interest the moment Deano informed about it.
> 
> It's use seem to be mostly "limited by imagination" though especially well suited for constant/long lasting leeching which benefits from low concentrations of leech liquor and/or dissolved metals.
> My reluctance to comment so far has been that I haven't come to a point where I have accumulated any information to share :wink: In fact my graphite electrode disappeared on route from Beijing to Europe and my felt has just arrived in town.
> I do not have access to a 3D printer as Jon has so my initial construction will not be as nice as his.



You've grasped the point perfectly Ygg. The possibilities and applications are almost endless. 

Kurt and Ygg. I already have 4 people who want prototypes to work with actively so they can provide feedback in the beta testing which will lead to improvements/additions. If you both are happy to use them and be part of that program then adding a couple more delivery addresses really makes very little difference.  The cells will have anodes and cathode material with them so you only need the peristaltic pump and your own pipework and electrical circuit to make them operational.


----------



## Yggdrasil

I'd be very honored to be a part of such a test, but I'm not set up to start yet. 
It'll be a couple of months until I'm ready.
In light of this, it would be more sensible to give someone that is more prepared a chance. :wink:  

I have planned to do a few test runs to streamline the setup prior to going "live".
By the way the first process I'm planning to test it on, will be a long lasting HCl/Cl leech of cats.
Next will be AR on same. This way I will be able to compare. 
I have two identical cats from the same car  
By the way do anyone know if it is anything to gain by reintroducing the NoX gases from AR into the leech liquor by peristaltic pumps? Maybe with some extra H2O2 into it?

In time I may or may not proceed to CN in the way of thiocyanat or real CN on Gold pins and fingers.
I'm not very confident to take the plunge into the cyanide territory yet.

Edited for clarity


----------



## nickvc

Yggdrasil said:


> I'd be very honored to be a part of such a test, but I'm not set up to start yet.
> It'll be a couple of months until I'm ready.
> In light of this, it would be more sensible to give someone that is more prepared a chance. :wink:
> 
> I have planned to do a few test runs to streamline the setup prior to going "live".
> By the way the first process I'm planning to test it on, will be a long lasting HCl/Cl leech of cats.
> Next will be AR on same. This way I will be able to compare.
> I have two identical cats from the same car
> By the way do anyone know if it is anything to gain by reintroducing the NoX gases from AR into the leech liquor by peristaltic pumps? Maybe with some extra H2O2 into it?
> 
> In time I may or may not proceed to CN in the way of thiocyanat or real CN on Gold pins and fingers.
> I'm not very confident to take the plunge into the cyanide territory yet.
> 
> Edited for clarity




Can I say you are wasting your time and money trying to wet refine cats unless they are free.
The other problem is you are left with a very toxic waste as it contains PGM salts which are highly toxic, not to say lethal, from the residues after leaching as it's virtually impossible to remove all the acids.


----------



## Yggdrasil

Duly noted Nick.
Lets get back to topic here please.
This thread deserves to be kept as clean as possible, sorry about the distraction I opened up to in my last post.


----------



## patnor1011

I cant wait to see that cell working. I do have enough material to feed that baby for a long time. :lol:


----------



## kurtak

anachronism said:


> Kurt and Ygg. I already have 4 people who want prototypes to work with actively so they can provide feedback in the beta testing which will lead to improvements/additions. If you both are happy to use them and be part of that program then adding a couple more delivery addresses really makes very little difference.  The cells will have anodes and cathode material with them so you only need the peristaltic pump and your own pipework and electrical circuit to make them operational.



:shock: WOW Jon - that is one heck of an offer - but like Yggdrasil in honesty I to will turn your offer down

The reason for that is that right now I am actually scaling back on the amount of refining I am doing - I am not quitting - just scaling back - sort of regrouping at this time

The reason for that is as you know I have been taking care of my mom & dad - mom is now gone & dad is 93 & is not doing so well - when he is gone it is may intent to sell my place here in Wisconsin & move back out to the pacific northwest - so I am currently really spending most of my time cleaning up & doing repairs on the property so the property can be more ready for sale in the short term (after dad is gone) rather then waiting & dealing with the clean up & repairs after he is gone

So I have limited my refining to a few select costumers - so though I am still refining IMO its not steady enough to honestly justify taking you up on your "very" generous offer

But THANK YOU very much for making me that offer Jon :!: --- it was truly a :G offer

Kurt


----------



## anachronism

No worries gents. Call it a rain check as you say in the US.


----------



## autumnwillow

Is the concept of this process like an electrowinning cell with a circulating solution?

Having a cyclyndrical vessel's purpose is more surface area?
Circulating the liquid makes sure that most of the metals are removed from the solution?

That this process can be used for chloride/sulfuric wastes like what the stock pot contains? If so then this is better than copper cementation and/or iron cementation as there is no need to add any more metals to the waste solution assuming that it can take out metals the same as cementation does. It was also noted at Deano's thread that chlorine gas will be produced when this method is done on wastes.

As for cyanide, will this system get a better recovery rate than zinc cementation? Although this system is more economical for those who usually run the same batch of materials they can keep on reusing the cyanide solution. I do not think a refiner like me who usually process different types of materials everyday will have this device as useful yet. Correct me if I am wrong though.

I do believe that electrowinning will never get 99% of the metals out of the solution, but having the solution re-circulated a lot of times will get up to what %?

Or do I have the wrong idea about this method? Heh


----------



## autumnwillow

Another thing that I do not understand is that in electrolysis the anode produces oxygen which is the oxidizer for a CN leach and since this is circulating solution wouldn't that dissolve the metals in the cathode? Hence the CN solution is actually destroyed in this process?


----------



## nickvc

The cell will strip all metals from any solution if it's run correctly and allow for the solution to be reused or make it safe for neutralisation and disposal, within the legal limits set by most agencies.
With cyanide solutions you need to add extra chemical to reuse the solution but you still only have one solution not dozens so the waste stream is reduced to a much more easily treated amount.
You are correct about acid solutions but you can simply pump the gases through water to create HCl which can then be reused for processing more material.
With cyanide yes it will give better results than zinc if you continually run your solution through the cell, all you need to do to recover your gold is to remove the felt, rinse well with water and dissolve the values in acid, the felt can the be rinsed again ready to be reused.without access to assaying you may need to put the solution through the cell again and test to check if you have any more values plating out before stripping more material.
The zinc cementation method works but again without assays it's hard to be sure all the values are out of solution which can be a real pain if you are running unknown yielding materials, one trick I used was to add small pieces of aluminium foil to the solution after dropping the gold, if it started to turn slightly brown you still had gold in your solution.
From memory of the last such cell I saw tested it can remove metals down to parts per million, but perhaps Deano can provide better information on this cell.


----------



## autumnwillow

I'll build one if ever I get some free time. I'm still having trouble with wastes as I have no supplier of floc agents and filtering is very slow due to iron hydroxides.

Not sure why anachroism used a 3d printed model?
I believe this can be done cheaply with PVC pipes, pumps and a rectifier. Shouldn't cost more than $300.


----------



## anachronism

autumnwillow said:


> Not sure why anachroism used a 3d printed model?
> I believe this can be done cheaply with PVC pipes, pumps and a rectifier. Shouldn't cost more than $300.
> 
> You're quite right it could be done cheaply. In fact I have already done it that way as the photos of my pipe built model show. To answer your question: I did it with a 3D printer because I no longer wanted to "make do." I wanted to develop something properly and professionally that made my life easier and allowed me to run good sized batches without having to jury rig equipment. I also wanted to see how far I could take the simply brilliant concept that Dean gave us, and the pvc pipe and drain pipe method doesn't do it justice.



A picture tells a thousand words, so here is the first prototype fully printed below guys. This is in the correct material and at the correct detail. That is all printed in one piece with the pipework printed internally. The rough concept prints in ABS are to the left to add context.


----------



## Yggdrasil

Hi Jon.
Impressive smoothness as far as I can see. What material is it, if I may ask?
The difference between the prototype and end product is because of increased print resolution alone or material as well?
Are the pipe inside for the overflow?
It seems that the felt is supposed to be in between the two perforated screens.
Which thickness are you using?

Picture of the end cap as well please  :wink:


----------



## anachronism

Yggdrasil said:


> Hi Jon.
> Impressive smoothness as far as I can see. What material is it, if I may ask?
> 
> Sure, the material is Polypropylene. It's got the right mix of chemical resistances and material properties for the task. Printing it is interesting but we've worked that part out properly now.
> 
> The difference between the prototype and end product is because of increased print resolution alone or material as well?
> 
> Yes to both and in addition a number of dimensional changes and improvements over the original.
> 
> Are the pipe inside for the overflow?
> 
> Yes the overflow is the pipe you can see on the picture. Below the height of the outer cell wall.
> 
> It seems that the felt is supposed to be in between the two perforated screens.
> Which thickness are you using?
> 
> Yes it goes between the two screens, and the felt I use is 10mm thick. You could use thinner felt and slightly thicker felt as well.
> 
> 
> Picture of the end cap as well please  :wink:
> 
> I will post one tomorrow. I'm just working on an amendment to the design this evening. It only takes a couple of hours to print that part.


----------



## Yggdrasil

Thanks Jon!

Is it possible to split it into separate parts?
The walls from the bottom as well? For cleaning and repairs or what not?
Or is it supposed to be used and only rinsed now and then? (that might be sufficient though)

I love the way the development is going and would not be surprised if this ends up as one of our main tools.

Thanks for the effort, time and information Jon and Deano (or is it Dean)


----------



## anachronism

Yggdrasil said:


> Thanks Jon!
> 
> Is it possible to split it into separate parts? No
> The walls from the bottom as well? For cleaning and repairs or what not? Not needed, spray it out occasionally as required.
> Or is it supposed to be used and only rinsed now and then? (that might be sufficient though)
> 
> I love the way the development is going and would not be surprised if this ends up as one of our main tools. Thanks I appreciate that.
> 
> Thanks for the effort, time and information Jon and Deano (or is it Dean)  It's Dean, I just think he likes the "o" 'cos it makes him sound trendy


----------



## nickvc

Looking good mate we just need trials now to prove the concept and iron out any problems.


----------



## anachronism

nickvc said:


> Looking good mate we just need trials now to prove the concept and iron out any problems.
> 
> Hi Nick. Trials already done mate. It works. I have gold and silver recovered using the cell even from it's old form. I don't doubt Dean's knowledge and you have spoken to him yourself too. This is nothing more than Dean's cell on steroids if you will pardon the analogy.


----------



## 4metals

So Deano becomes Dean, does that mean you become Jono, because it sounds trendy!  

How do you plan to attatch the power suppy to the carbon felt? Is there a long strip of metal that fits in the groove where the felt starts and ends and locks in the felt and provides electrical contact? 

I think this cell will work well on cyanide peroxide bombing solutions that jewelers generate. It should easily grab the gold and all metals in the alloy from the solution and in a second run destroy the cyanide. This solution poses problems for jewelers and some refiners who have a tough time treating cyanide waste.


----------



## patnor1011

Jono.... :lol: 
Nearly choked on my coffee...
Good one 4metals.


----------



## autumnwillow

Very nice prints. I hope you could sell some cheaply for us! I'd love to use this on my wastes, its getting out of control.


----------



## 4metals

CeraMaterials from Rickbb's link is about 30 miles from my house so I went for a visit. Impressive inventory, they can provide sheet or pre cut felt. I'm thinking 1cm thick?


----------



## anachronism

Thinner 4metals- go for 10mm

Edit. I am a complete muppet because I read your post as 1 inch..... of course 1cm is in fact 10mm.... *slaps himself soundly*


----------



## FrugalRefiner

Yep, that metric system is darned tricky!  

Dave


----------



## anachronism

autumnwillow said:


> Very nice prints. I hope you could sell some cheaply for us! I'd love to use this on my wastes, its getting out of control.



Your post raises a very good question Autumn. 

If you couple the cell with an effective leach tank system then you can kiss goodbye to AP. It won't be needed ever again. You can throw your sulphuric cell in the bin too whilst you're at it. No more acid/bleach processes. Processors and fingers become a one step recovery as do plated boards. You can suddenly process a whole host of material that would previously have been beyond the home refiner. Your income would shoot through the roof. 

One initial cost layout, and a tiny ongoing cost for raw chemicals.

Then when you're done you can treat your waste in an environmentally friendly way. So my question would be what would you define as "cheaply" given what this would do for you?

It's a genuine and open question and I'd welcome your input and anyone else who fancies pitching in.


----------



## anachronism

FrugalRefiner said:


> Yep, that metric system is darned tricky!
> 
> Dave



I deserved that Dave.


----------



## autumnwillow

Pricing would be up to you but do not forget the discount for GRF members!


----------



## anachronism

autumnwillow said:


> Pricing would be up to you but do not forget the discount for GRF members!



Haha to be honest my main focus is getting a completely operational system. Ironing out the bumps in the road to develop a complete, self contained leach circuit is one of the most interesting things I have done in years. The most expensive single piece for the leach circuit arrived today. Do bear in mind that I am designing my own to operate on a semi-commercial/commercial scale and it can all be scaled down as well as up.


----------



## kurtak

anachronism said:


> 4metals said:
> 
> 
> 
> Thanks for the update. With the cell you are printing, what is the area of the fabric that will be exposed to the leach solution. I know the actual surface area is exponentially higher than the physical piece of felt you use, but what size piece of felt will this accommodate? And what volume of solution will the entire cell contain when operating?
> 
> For the smaller cell approx 140 sq cm of cathode, and as mentioned before this scales depending upon the height of the cell used. Volume of liquid approx 310 cubic cm in this version.
> 
> 
> Sent from my iPhone using Tapatalk
Click to expand...


And in response 4metals posted



> Wow, that i s less than 22 square inches of fabric and 11 fluid ounces of strip in the cell. (I converted these numbers to help those of us who live in countries that do not recognize the wisdom of the metric system)



That is one small cell considering you are talk about a cathode (felt) that is only about 5 inches square (= 25 sq. in.) & a pint is 16 oz. 

This brings to mind a few questions I have based on that size cell

1) How many amps would be required on the current output side of a power supply to run that size cell ?

I ask because my power supply is only 10 amp - is that enough amps (its a high end power supply - not a cheap $100 ebay supply - but only 10 amp output)

2) What volt setting do you want to run at ?

3) Flow rate (for this "pint" size cell) again I understand that flow rate can be "somewhat" variable but I assume there is an "at least" but "not more then" rate for optimum deposit to the cathode ? 

4) How much gold can you expect to load on the cathode before the cathode needs to be changed ? (I know that's going to be a variable of "at least" and "as much as")

Kurt


----------



## 4metals

Operational question?

As the concentration of the dissolved metals in solution decreases do you see a substantial decrease in voltage or amperage? Or does the nature of the stripping solutions high conductivity keep the draw consistent? This question is more for those not inclined to run an AA to analyze the solutions with the hope that there is some kind of sign that the cell has stripped all of the metals. 

And while you contemplate power questions for Kurt's question, does use for stripping waste of its metals followed by reversing polarity to destroy the strip solution require substantially more power than the normal operation to recover values?


----------



## anachronism

kurtak said:


> That is one small cell considering you are talk about a cathode (felt) that is only about 5 inches square (= 25 sq. in.) & a pint is 16 oz.
> 
> This brings to mind a few questions I have based on that size cell
> 
> 1) How many amps would be required on the current output side of a power supply to run that size cell ?
> 
> I honestly don't know the answer to that question yet Kurt. The hand built one was a lot larger and that was taking around 15 amps in order to do anything meaningful and I know that Dean uses cells that take up to 200 amps albeit those are larger scale. This one is truly a miniaturised version and it's theoretcially possible that that it would run properly under 10 amps but I will only know when I have run the practical tests on it with various liquors.
> 
> I ask because my power supply is only 10 amp - is that enough amps (its a high end power supply - not a cheap $100 ebay supply - but only 10 amp output)
> 
> Remember that you need an over current as per my previous posts however as per the above I will be able to share the results shortly.
> 
> 2) What volt setting do you want to run at ?
> 
> You don't run at a set voltage. You vary the voltage to increase the current flow until your cell is stripping properly. The required current depends upon the tenor of your liquor. The more metal in the solution, the more current. Since the whole system is designed to keep the leach tenor low and therefore maximise the leach rate the current needed should be lower than that used in a larger cell.
> 
> 3) Flow rate (for this "pint" size cell) again I understand that flow rate can be "somewhat" variable but I assume there is an "at least" but "not more then" rate for optimum deposit to the cathode ?
> 
> The flow rate is determined by you and what you are trying to achieve. A slower flow rate from between the anode/cathode will be more likely to completely strip the metals than a fast flow rate. If you are merely looking to lower the tenor of your solution prior to passing it back to the leach then a faster flow rate can be used. To be succint- for me a slow flow rate is 1 litre per hour, and you can increase this many many times dependant upon the conditions you are working with and the desired end result.
> 
> 4) How much gold can you expect to load on the cathode before the cathode needs to be changed ? (I know that's going to be a variable of "at least" and "as much as")
> 
> That's a pretty simple one Kurt, but change your thinking to "metal" not gold. Your cathode will ultimately clog up and that's your ultimate end point in the lifespan of the cathode within the cell. As you are drawing from the bottom of the cell, the cathode will load fastest at the bottom and work upwards. Ultimately you will have no liquor coming back out from the cell in the return pipe. Given that a Kg of gold is smaller than a packet of 20 smokes, and you can calculate the volume of the felt from the dimensions here then you are looking at a substantial amount even in this micro cell.
> 
> Kurt


----------



## anachronism

4metals said:


> Operational question?
> 
> As the concentration of the dissolved metals in solution decreases do you see a substantial decrease in voltage or amperage? Or does the nature of the stripping solutions high conductivity keep the draw consistent? This question is more for those not inclined to run an AA to analyze the solutions with the hope that there is some kind of sign that the cell has stripped all of the metals.
> 
> Simple answer is Yes. As the tenor of your liquor decreases, the current flow reduces, assuming you have not altered the voltage.
> 
> 
> And while you contemplate power questions for Kurt's question, does use for stripping waste of its metals followed by reversing polarity to destroy the strip solution require substantially more power than the normal operation to recover values?
> 
> I need to run more tests on that phase before giving a definite answer 4metals. The vast majority of the practical work to date has been on the strip circuit.


----------



## 4metals

Clarification please?

You use the word "tenor" often. It is not a chemical term and as far as I know it refers to some fat guy singing in the choir. Maybe this is just a case of your side of the pond vs my side of the pond but for clarification could you choose a term more appropriate to electrochemistry?


----------



## g_axelsson

I've heard Deano mentioning tenor a lot, my understanding is that it means gold loading, how much gold there is in solution, concentration. I don't know if it is a mining term or if it is used in other areas.

Doing some more searches (Google scholar, online dictionaries and so on) I get a feeling that sometimes means "concentration at a steady state" but commonly is used just for concentration.

I should have done some reading on the forum, in http://goldrefiningforum.com/phpBB3/viewtopic.php?f=44&t=23120&p=243183&hilit=tenor#p243183


Deano said:


> Gold tenor is the concentration of the gold in the leach liquor. The higher the tenor the more gold is in a unit volume of liquor.



Göran


----------



## 4metals

Any updates on the system? Perhaps some photo's of your new 3D printed cell in action.


----------



## chuckgambale

I hope to see you soon my friend. This one here is a game changer for the small guy.


----------



## anachronism

I know it seems like this one stalled. It didn't 8) 

We have been sorting out various things with regards to different chemistry relating to different types of base solutions and have got to the point where we can build the first complete rig. The rig is designed around completing the whole process in an area no greater than 2 cubic metres from start to end. That includes the reaction vessel, the header tank, the pumps, pipework, electrical conduits, cells and all ancillary equipment. The unit is being constructed in 316 SS giving flexibility to use a variety of leaches. Naturally that's involved quite an investment in raw materials and the TIG welding has been quite "involved."

The pics below show the chassis along with the base catch tank system being implemented.


----------



## 4metals

Good to see this thread starting up again, to summarize, you are using the same cell you devised from discussions with Deano, and now incorporating a tank and closed loop plumbing to effectively use one system for different leaches depending on the feedstock. 

How are you addressing the tendency for circuit boards or e-scrap to trap air and not allow for proper circulation / wetting by the leachate? Are you moving the material during the strip process? If not, this can greatly effect your ability to process large lots as the solution needs to flow freely and not be trapped in the voids created by static parts which are not moving, tumbling, or somehow allowing for the circulation. 

This is a quantum leap forward from the carbon felt cell to an entire system incorporating pumps, power supply, leach tanks and many other goodies you have yet to unveil.


----------



## snoman701

So a couple of things...

For people without access to a 3D printer, in the US there is a company called Campbell Manufacturing that makes PVC well points. These are pieces of standard diameter PVC that will have a ton of small slits cut in the pipe. They are dirt cheap compared to a normal well point. Usually about $20 for a 3 or 4 foot piece of it. They also make it in many different diameters. 

Now...as for the system itself...this is awesome. I sort of wish I would not have read about it, as I'm not going to be thinking about it constantly!

My question is in regards to the use of AA or gravimetric method of determining solution concentration. It seems that these would be required only to maximize the efficiency of the system? If you recirculate leach liquor that has not yet been entirely stripped of metals, will it not get another chance to be stripped completely the next time around? It may just take a couple extra cycles...at only the cost of the clock and the carbon rod?


----------



## snoman701

So what I haven't figured out is what kind of felt is this? The PAN or the Rayon?

Anybody figure out an Amazon product? Plumber Pad? Weld Blanket? etc?


----------



## anachronism

Straightforward carbon Felt Sno. between 6mm and 10mm depending on your cell design.


----------



## snoman701

anachronism said:


> Straightforward carbon Felt Sno. between 6mm and 10mm depending on your cell design.



Yeah, the product "carbon felt" offers really nothing in the way of products via amazon/other online sales places. Carbon felt soundproofing gives even less.

I can usually find sources for stuff local, but I have a feeling I'll have to order from ceramaterials.


----------



## snoman701

I did try to order a piece from a backpacking hobbiest site. It has the right appearance, we'll see once it arrives. 

I'd order from ceramaterials, but they claim to have a $100 minimum order. I'll see if they'll sell a couple square feet for R&D work later. 

If not, it appears fuel cell hobbiests are using the same type of felt for battery development.


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## Iggy-poo

anachronism said:


> autumnwillow said:
> 
> 
> 
> Pricing would be up to you but do not forget the discount for GRF members!
> 
> 
> 
> 
> Haha to be honest my main focus is getting a completely operational system. Ironing out the bumps in the road to develop a complete, self contained leach circuit is one of the most interesting things I have done in years. The most expensive single piece for the leach circuit arrived today. Do bear in mind that I am designing my own to operate on a semi-commercial/commercial scale and it can all be scaled down as well as up.
Click to expand...

4Metals joggged my memory with the mention of aquariums. Rather than use a fancy pump, wouldn't it be easier to just use the technique of a bubble column generated by an air pump to help circulate the stripping solution. One added benefit would be the aeration of the solution to increase the activity.


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## snoman701

No, as maintaining the levels is pretty important to proper function. You may be able to do away with one of the metering pumps, but it is going to be a lot easier to control with two. 

A two pump system is actually commonly used as an introductory controls tutorial in PLC programming.


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## Iggy-poo

snoman701 said:


> No, as maintaining the levels is pretty important to proper function. You may be able to do away with one of the metering pumps, but it is going to be a lot easier to control with two.
> 
> A two pump system is actually commonly used as an introductory controls tutorial in PLC programming.



if you have the cell in the stripping tank (think of an aquarium) there is no problem maintaining level.


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## autumnwillow

Any updates on this? I believe you have a new fancy equipment for this setup!

Apart from cyanide. Have you tried it on chloride wastes? sulfuric wastes? nitric wastes?


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## anachronism

It's taken a long time to get the material correct but we finally cracked that. 

To your second question - no, we haven't used it for those things to any extent.


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## fishaholic5

For someone like me this system has obvious benefits. Although I'm not using cyanide, the application to recovery of gold from chloride solutions or refining silver dore is mind blowing  
I'm processing ore that is mainly bromargyrite, with gold, palladium and traces of other pgm's and have been looking at methods for refining the silver dore 
A huge thanks to everyone on this site for the wealth of information and assistance they provide. This forum is an amazing resource.


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## Rachello

This is ingenious. 

Have you guys tested all results through a voltammogram? Cornell has one & I know my professor will let us dabble with it. 

We could run an unlimited number of tests assuming you ask the right questions & be political... (Anacronym or Acronym) both are interchangeable as one & the same. That equates to a sound reasoning of electromagnetic chemistry & the science behind it.

After all testing results we would have to submit a paper of “precedence” giving preconceived notion of the unfounded. 

All this would have to be approved by the “councilor” of choice. 

It is not something to F w/. 

You guys have a technique not yet explored I’ll do my due diligence & work with the powers that be.

Rachel


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## Rachello

As an inventor of 37 patents, I can tell you; it is not easy. It is something I struggle with every day. Those struggles consume my life. I look at my wall of Success & forget how I got there. 

You want to know about refining? I have given alll I need to tell. Im exhausted. 
If you know something no one else does, it is your duty as a scientist or a student of science to uphold society & it’s knowledge, to discovery. 

The unknown, is Its vanse escape of the discoverable , is horrifyingly apparent for those that died for the cause... & is inexcusable for those that haven’t. 

Rachel


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## Lou

37 patents!! wow, good for you!


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## Dr.xyz

Patent database search did not find any...?


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## Rachello

Lol, most were ideas... I didn’t want to lose & will revisit some day. I look at a bunch & think how I’ve grown since I thought it. A couple (I think) are really good & the rest I believe might be great with a little more engineering. 

The point is not to hesitate. Make it yours before someone else makes it theirs. Look at what you have through the looking glass & rid yourself of self-doubt. 

I do have a different mindset as most. My Mom has so so many patents for the years she worked for xerox it is amazing! She was a Senior Research scientist & chemist. 

She then worked for Bausch & Lomb as a Patent infringement specialist. She constructively criticizes everything I do. If it’s deemed worthy in her eyes she will pull a few strings so the cost hopefully offsets the benefits. 

I was trained @ a very early age to grab hold of my ideas & run with them...or at the very least make them legally mine  

There are so many very smart people on here with original ideas. A lot due to the fact that they did not learn the conventional way & therefore think unconventionally. Making whole avenues of original thought & creativity. It’s amazing!

If you know you have something good, don’t lose it. In this world today we have to protect what we produce. 

Rachel


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## Rachello

Dr.xyz, 

I searched through the patent database. Without spending hours on all the parameters visited & summing it up into one search & then reading & cross referencing through all patents with similar search parameters...no I did not find any. 

That is not to say it doesn’t exist, but that I just didn’t find any. 

Rachel


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## Rachello

I thought it important to add that Voltammograms are the results of electrochemical experiments that can be performed with a potentiostat. 

You can build one. Look it up. 

Rachel


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## Lou

Rachello,

I think he’s saying you should link your patents as a search for yours does not show up.

37 issued patents is something to be proud of!


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## Rachello

Lou, 

I didn’t realize people actually linked thier patents to the forum. Makes sense to link although then you might wonder why I did. Most of mine would have no place in gold refining. For example one I like to call “Crazy Bow Magic” lol & several for bow hunting that involve an insert that allows you to turn a normal arrow into a tracker. You can then locate through your phone or another, simpler, hand-held device so that you “never lose you deer or your arrow again”, a great idea but not really cost-feasible to produce at a price the average hunter could afford. Along with several other drawbacks I have yet to find the answers to. Another is on geothermal heating and cooling. Yet another is a gardening aparatus. 

Others, like I said might be brilliant thoughts but need a little more engineering & I wouldn’t want to link so roughly 50,000 members can take them to the next step. At which point would not be considered infringement  

My point is that others should take the same steps for their ideas. A lot of people don’t even think of it & that idea could be lost to them. 

It is not that many if you look at all I would have done without my Mom reining me in. I am a tad bit obsessive & think every good idea I have, is the best I ever had & should be deserving of a patent! Lol. 

The hardest part for me is when I find my apiphany was already thought of. Its always so disheartening & happens more often than it doesn’t. 

Rachel


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## Rachello

....crazy bow magic has nothing to do with bow hunting. It is a specific tool I designed to create elaborate bows easily for any occasion. Bow, as in using actual ribbon.  

Doesn’t really fit here...lol  

R


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## butcher

I thought a bow tracker was for finding your sweetheart.


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## Rachello

Lol  I met my hubby & a month later we ran away & eloped. 12 years & 3 kids later he is just as sweet. 

I didn’t need a tracker arrow but I know several people that would find it useful!  

R


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