Dealing with Waste

[Lobby]

, I have a bucket of copper nitrate

Patch,

I save my copper nitrate to use an an electrolyte for sterling silver. Dilute/concentrate the copper nitrate solution to 6M (moles per liter) or less and use a graphite cathode and anode. Plate out the copper sponge until the solution is an very light blue color and then switch out the positive lead with a sterling silver one. Bag the anode to catch and PGMs or gold that may have made it into your sterling scrap (ie: gold or rhodium plating). The copper will plate out as a moss. Periodically you will need to dip out the moss so it does not fall off the cathode and end up in the solution. The silver will saturated the solution and remain in the bottom of the cell or in solution.

You can also dehydrate the copper nitrate solution and decompose it into NO2 and Copper oxide at relatively low temperatures (less than 150C). The NO2 can be bubbled into water to form nitric acid or into a basic solution to form sodium nitrate which can be used in poor man's AR or nitric.

Steve

Pardon for bumping an old thread, but I think I see what you're after.

What you're suggesting recovers both the copper (as sponge, prob on the anode), and converts the nitrate ion to nitric acid. Then when the anode is switched out (taking the copper with it), the nitric dissolves the silver, eventually making the silver nitrate solution needed for the silver cell.

Did I get that right?

 

[lazersteve]

Here's what the reply above was based upon:

Copper Nitrate Recycling

Steve

 

[burningsuntech]

Welcome 4metals. Im new here and have begun reading Hokes work. I don't know alot about chemistry but when in H.S. it was my favorite subject (or was it the teacher Miss Reed?)

Anyway Im glad you posted about waste treatment and am planning a system to deal with it once I clear out a space for my small operation. I have tested some of the info in Hokes work and am storing my wastes in safe containers till I can deal with it this summer and ramp up my small operation.

This is a lot of fun and I am looking forward to sharing what I have discovered, abeit perhaps what everyone already knows. But hey, good knowledge repeated only amplifies good knowledge learned.

Thanks to the forum moderators and Noxx for hosting and all you guys here, Im looking forward to a SAFE and Satisfying experience.

 

[Digitaria]

On a similar note: I found this reference:
Chemical Experiments pg 27 of 265 / paragraph 120
A great portion of the scraps of tinned iron, broken cast-iron vessels are sold as useless in London, is carried and thrown into certain streams in Scotland and Wales, the waters of which are impregnated with copper. Here lying a considerable time they abstract the copper; at the same time the iron itself is dissolved. The metallic mass, which is afterward taken up, is therefore entirely copper.

 

[pcecycle]

I am trying to process some old hcl that was used on a batch of cpus, roughly one gallon. I used copper to drop any leftover PMs then used iron to drop the copper. Now I am trying to neutralize the acid. I started out using baking soda, but the solution was stiil reacting strongly after using an entire 1 pound box. I bought a bottle of lye (label says 100% NaOH) but when added to the solution, there was no reaction at all. Added some more baking soda and still get a strong reaction. What is the best, least expensive chemical to use to neutralize HCL? I have another 2-3 gallons of HCL that need to be neutralized, and buying 10+ pounds of baking soda could get expensive!

Thanks

Mike

 

[butcher]

NaOH is a stronger base, the baking soda ( a weaker base) produces a lot more of gas CO2.
All of that CO2 gas foaming your solution over can look more reactive, as we know looks can be deceiving.

HCl and NaOH, form salt water.
HCl + NaOH --> NaCl + H2O

Sodium bicarbonate NaHCO3 (baking soda) and HCl will form salt water in carbonic acid, then the carbonic acid breaks down to water and CO2 gas, in a two step reaction.

HCl + NaHCO3 --> NaCl + H2CO3 (aq)
Then
H2CO3 --> H2O + CO2(g)
Basically leaving salt water.

You are dealing with an acidic solution but it will not be as acidic as the HCl acid itself would be.
for a gallon of HCl you could use about 5.5 pounds of sodium bicarbonate.

http://www.chagrinsehazmat.com/PDF%20Documents/RestrictedFiles/PDF%20Files/Neutralization%20chart.pdf

 

[Lou]

http://www.law.cornell.edu/cfr/text/40/part-421/subpart-X

 

[autumnwillow]

When using caustic soda to precipitate iron the sludge is just too hard to filter.
Magnesium Hydroxide is very expensive.
I haven't tried soda ash and lime. What do you guys use to treat ferric chloride solutions?

 

[nickvc]

You could try wicking as described by Goldsilverpro.

 

[autumnwillow]

The wick works but I do not think it is suitable for stock pot waste quantity. There's a thread here somewhere where a guy used sand in an inverted bottle. I can't find it anymore! :|

Edit to add:
Whats the effect of throwing the iron precipitates along with the treated water in the drain?

Edit to add again:
Maybe there's a flocculating agent for this? A simple chemical perhaps?

 

[Barren Realms 007]

The wick works but I do not think it is suitable for stock pot waste quantity. There's a thread here somewhere where a guy used sand in an inverted bottle. I can't find it anymore! :|

Edit to add:
Whats the effect of throwing the iron precipitates along with the treated water in the drain?

Edit to add again:
Maybe there's a flocculating agent for this? A simple chemical perhaps?

Maybe there is patience involved in letting the material settle then siphon of the liquid then let the solids dry out so you can dispose of them. 8)

 

[autumnwillow]

Maybe there is patience involved in letting the material settle then siphon of the liquid then let the solids dry out so you can dispose of them. 8)

Two days. And they still are not settling.
I think I need a coagulant rather than a flocculant.

 

[jason_recliner]

Whats the effect of throwing the iron precipitates along with the treated water in the drain?

Hmm... Check with your local EPA office. Don't forget to mention a chance of some tin, nickel, copper, lead or maybe some other toxic nasties sneaking in.

Ok, that's enough of facetious mode... Now switching to disapproving environmentalist mode...
Responsible disposal is part of refining. It costs you time and money, but it must be factored in.

I would not be at all surprised if dumping metal sludges down the drain leads to a future blockage of said drain. It will settle in the low points like you will not believe.

My own waste settles sometime over the couple of weeks before I even check on it. Luxury of a hobbyist. If you don't have that long, you may need to allocate more storage, or find ways to be more frugal about creating waste in the first place.

 

[kurtak]

You could try wicking as described by Goldsilverpro.

Wick filtering is the way to go - I will "try" to post pics & info of my set up later (I am really busy right now)

However I have now reached a level of creating waste now that I simply adjust the PH to neutral (with NaOH) & send it out in 55 gallon drums - cost $150 per drum - well worth the cost in the time it saves - it goes to the same company I get my chems from (they are an industrial chem supplies & handle waste as well)

Kurt

 

[autumnwillow]

You could try wicking as described by Goldsilverpro.

Wick filtering is the way to go - I will "try" to post pics & info of my set up later (I am really busy right now)

However I have now reached a level of creating waste now that I simply adjust the PH to neutral (with NaOH) & send it out in 55 gallon drums - cost $150 per drum - well worth the cost in the time it saves - it goes to the same company I get my chems from (they are an industrial chem supplies & handle waste as well)

Kurt

I'll try to contact local waste management companies and see how much they charge. If the price is right I'll just send them away.

Edit to add:
Kurtak have you not considered buying a filter press? You are sending drums at $150 per drum. I guess with enough savings you could buy a filter press or have I missed something?

 

[Topher_osAUrus]

Maybe there is patience involved in letting the material settle then siphon of the liquid then let the solids dry out so you can dispose of them. 8)

Two days. And they still are not settling.
I think I need a coagulant rather than a flocculant.

Miss Hoke says that sometimes settling for several days is required (when dealing with powdered gold)

We all know gold is quite heavy.

So, the lighter elements may take exponentially longer than that.

On my waste stream i try to let it settle for a couple of weeks, then i siphon off about 3/4ths of it with this (see pic).

I then use the wick system to get the rest of it from the solids.

The siphon in the picture was 10.99 from my local home-brew store, where i buy my SMB in bulk as well. It has lasted me 5 months so far, and hasnt even began to degrade yet.

The steing is to tie it up/off so it doesnt hit bottom when im using smaller 3 gallon buckets.

 

[4metals]

Kurtak have you not considered buying a filter press? You are sending drums at $150 per drum. I guess with enough savings you could buy a filter press or have I missed something?

Just because you can pass your waste through a filter press does not mean it is clean enough to discharge legally.

Every municipality has discharge limits that refiners must adhere to. This requires testing and reporting if you are doing this on a commercial scale. You can't just pump the contents of a 55 gallon drum through a filter press and run it down the drain. If and when the environmental inspectors show up you just can't say you dumped it, they want to see proof of testing and your treatment system. I have installed many of these systems and they do pay for themselves but there is a time when you are a smaller generator when it is less expensive to just drum it up and ship it off as a manifested waste. And then when the inspectors come, you have the paper trail they love to look at saying you did it according to the law.

 

[kurtak]

Kurtak have you not considered buying a filter press? You are sending drums at $150 per drum. I guess with enough savings you could buy a filter press or have I missed something?

Just because you can pass your waste through a filter press does not mean it is clean enough to discharge legally.

Every municipality has discharge limits that refiners must adhere to. This requires testing and reporting if you are doing this on a commercial scale. You can't just pump the contents of a 55 gallon drum through a filter press and run it down the drain. If and when the environmental inspectors show up you just can't say you dumped it, they want to see proof of testing and your treatment system. I have installed many of these systems and they do pay for themselves but there is a time when you are a smaller generator when it is less expensive to just drum it up and ship it off as a manifested waste. And then when the inspectors come, you have the paper trail they love to look at saying you did it according to the law.

Correct :!:

Kurt

 

[Anonymous]

Dean's cell is extremely effective at removing metals from solutions. His thread explains in detail.

Edit: Here's a link to the thread. http://goldrefiningforum.com/phpBB3/viewtopic.php?f=37&t=21526&hilit=deano

 

[autumnwillow]

Judging from the time it takes to manage wastes, reagent costs and overhead costs I do think that its better to just drop everything with iron and have these ferric chloride wastes hauled.

With my current refining load and practice, I think I will probably just generate 50gallons in 3 months. I do not think they will even bother talking to me with this amount of waste. I'm trying to contact a few right now.

I do not live in the US where EPA exists, we have EMB instead here, but knowing our very corrupt and non-sense laws, red tape is just usual everywhere. I know a refiner who processes about 20kg of gold a week and just dump his wastes on the sewer. Our city rivers are all dead, most are clogged with landfill wastes. I do not want to add anything more to these malpractices that most of the people here are doing.

I do think that dealing with wastes should be talked more often here in the forum as probably some new members are just throwing their wastes down the sink. Steps in neutralizing the acids, dropping the heavy metals, adjusting pH, filtering then finally throwing it away or perhaps recycling some of the wastes. I do think that there could be other ways in dealing with wastes but it is just not much talked about.