Diamond / Stone Removal Process

[Romantic]

Thank you for the great post! I will post my results. I have plans this coming weekend but hope to try this on the following weekend.

 

[Digitaria]

This thread is very similar, perhaps you could add it to your knowledge?
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=39&t=19673

Edit: added another link
There is also a relevant post about the process of ar cleaning when stones are involved from 4metals
(scroll down to find it)http://goldrefiningforum.com/phpBB3/viewtopic.php?f=39&t=14432

 

[Romantic]

What type of gloves are recommended for handling the nitric and HCL?

 

[Digitaria]

Have you thought about how you are going to deal with the mass of fumes, that will come off your solution?
I learned the hard way, if you learn from my mistake, then you won't panic and endanger yourself and your family.
You will need a scrubber, to draw off your fumes and neutralise before discharging directly into the air.
I'm still researching mine, but getting there, slowly, slowly.

 

[4metals]

Generally I like to see heavier gloves used for handling, siphoning, and pouring the acids, Home Depot sells a PVC coated glove that hold up pretty well.http://www.homedepot.com/s/rubber g...rketing-_-digitas-_-weather_potw-_-tools_list They are about $6 a pair. For filtering and separating the undissolved metal and for adding powdered chemicals to drop the gold I like to use disposable latex gloves. Some guys can put on a pair of latex gloves and put the PVC gloves over them when they need them but use the same latex gloves all day either alone or under the PVC gloves. I go through a lot of latex gloves because I can't leave them on for too long, they drive me crazy. I'd rather deal with stains on my hands than the latex gloves but I wouldn't expect anyone else to do what is acceptable to me.

 

[nickvc]

Always used gauntlets but still end up with stained fingers and hands as I tend to take them off when dealing with more intricate processes
Not to be advised but admitting the truth, I'm used to the acids and bases and know when I really need to be cautious, like 4metals I can't stand tight gloves, but I'd tell everyone to wear gloves and be very careful around most of the chemicals we use.

 

[Romantic]

I have been thinking about that and here is my work in progress. If I am off my rocker, please tell me. Otherwise, if this looks like it might work...

Q1. How big should the bucket be? Homebrew shops sell 5 & 7 gal with rubber gaskets. Not sure if I can find a 2 gal with gasket.

Q2. How full and should it contain anything besides caustic soda and water?

Q3. Would landscape stones be just as effective as marbles (much cheaper)?

Q4. I am not sure that a vacuum pump will move enough air. How about a handheld vacuum?

This ideal is based on the following two sources....

http://www.ebay.com/itm/Portable-System-recovery-jewelry-be-225-00-/131073475841?_trksid=p2047675.l4066
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=49&t=5480#p47002

Have you thought about how you are going to deal with the mass of fumes, that will come off your solution?
I learned the hard way, if you learn from my mistake, then you won't panic and endanger yourself and your family.
You will need a scrubber, to draw off your fumes and neutralise before discharging directly into the air.
I'm still researching mine, but getting there, slowly, slowly.

 

[nickvc]

One fault I can see is that you are going to be pulling fumes through your pump its better to push the fumes than pull them if you can, the caustic fumes and mist will ruin your pump and fairly quickly.
The hood needs to be enclosed on all sides really with a lifting front to allow access and fresh air to be pulled through the system to vent off the fumes.
You can use an enclosed system using conical flasks in parallel, the first having you reaction in the second water and the third caustic and hydrogen peroxide mixed with water and then vented off outside, if your only doing small volumes this will work well and is easy to source the parts needed, not cheap maybe but easy and safe, to ensure the fumes are moved outside a fan can be fitted to a larger pipe into which you feed your outlet pipe to create a Venturi effect which only needs to move the air fairly gently so the small scrubbers have time to work.

 

[necromancer]

What type of gloves are recommended for handling the nitric and HCL?

you may find this handy. i forget who originally posted this.

 

[Romantic]

Thanks! What would be the ratio of caustic, hydrogen peroxide & water?

One fault I can see is that you are going to be pulling fumes through your pump its better to push the fumes than pull them if you can, the caustic fumes and mist will ruin your pump and fairly quickly.
The hood needs to be enclosed on all sides really with a lifting front to allow access and fresh air to be pulled through the system to vent off the fumes.
You can use an enclosed system using conical flasks in parallel, the first having you reaction in the second water and the third caustic and hydrogen peroxide mixed with water and then vented off outside, if your only doing small volumes this will work well and is easy to source the parts needed, not cheap maybe but easy and safe, to ensure the fumes are moved outside a fan can be fitted to a larger pipe into which you feed your outlet pipe to create a Venturi effect which only needs to move the air fairly gently so the small scrubbers have time to work.

 

[necromancer]

One fault I can see is that you are going to be pulling fumes through your pump its better to push the fumes than pull them if you can, the caustic fumes and mist will ruin your pump and fairly quickly.
The hood needs to be enclosed on all sides really with a lifting front to allow access and fresh air to be pulled through the system to vent off the fumes.
You can use an enclosed system using conical flasks in parallel, the first having you reaction in the second water and the third caustic and hydrogen peroxide mixed with water and then vented off outside, if your only doing small volumes this will work well and is easy to source the parts needed, not cheap maybe but easy and safe, to ensure the fumes are moved outside a fan can be fitted to a larger pipe into which you feed your outlet pipe to create a Venturi effect which only needs to move the air fairly gently so the small scrubbers have time to work.

i read here somewhere that the fumes need to be in a (home made 20L) scrubber for about 9 seconds

can someone confirm this please.

 

[nickvc]

In a sealed system there is little to worry about so long as the fumes pass through the two sealed scrubbing vessels, the percentages of scrubbing chemicals has been posted by 4metals to name one and I'm sure by many others use the search function and discover some more information that may well help 8)
If your using a traditional scrubber it all depends on the volume and speed of the fumes to ne scrubbed, the longer they linger in the scrubber the better the result, bear in mind even professional built systems are only about 80% effective if working to full efficiency.
All scrubbers need designing to the system that they need to neutralise there is no one does all set up.

 

[4metals]

The setup you have drawn is a far cry from a sealed system. The hood you have is totally exhausting thru the scrubber and that will require at least 200 CFM if the hood opening is 24" x 12". That flow through your scrubber will do nothing to your fumes, there is not enough contact time. You need 8 seconds contact time in the scrubber. A 5 gallon pail is about 2/3 of a cubic foot in inside area, the proper flow would be just under 5 CFM. Not to mention that a vacuum source would not provide sufficient exhaust for an open beaker in the hood.

You should have 2 exhausts, the hood exhaust is not scrubbed, it is just to move the air away from you to make the work area safe. The only fumes it should see are those which escape the beaker when you move the hose or open it to stir, the nasty fumes are scrubbed because they can be contained. That is what Nick means by a sealed system.

A commercial refiner working on small lots up to half a kilo in 4 liter beakers would look like this. The hood is exhausted to provide the clean work area and the hoses suck the fumes from the beakers to the scrubber. The watch glasses are not on these beakers.




A very cheap hood can be made like this, the drum has had the top cut off and a large powder funnel
http://www.usplastic.com/catalog/item.aspx?itemid=40274&catid=639&clickid=searchresults
is on top. Flex hose can go to an in line blower. GSP has had good results using a steel blower which just corrodes in a few years, if you scrub the bad stuff, it can last longer.



You still need a scrubber for NOx and there are several designs on this forum that can work for you. Dropping your gold with ferrous sulfate will also eliminate one particularly stinky process. While the scrubber will suck up the smell of metabisulfite, your scrubber will be a very low CFM and it may not be strong enough to draw an open precipitation. Ferrous is the answer.