Step by step disposal of acids after inquartation and ar?

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croakersoaker

Active member
Joined
Aug 22, 2009
Messages
40
Can anyone tell me where to find a step by step method to dispose of the leftover solutions after inquartation and aqua Regia. If Im correct I will have two solution right? A copper nitrate solution and an aqua Regia solution? Do they get mixed together at the end Or do the stay seperated.I did a search and read some threads that really seemed complicated. Is there a simple quick way to dispose of them after each refining. If not how do I store them.I have read in plastic containers, but what kind,'where do I get them. Can they be stored in the garage? I have been reading for hours everyday for weeks now and I think I understand pretty well about how to refine. But cannot find exact instructions on how to deal with this waste. And when I say that I mean from start to not at my house anymore.I'm really interested in doing this but I am stuck on this point. As I said I have read all the threads and used the search function I have seen a couPle threads that talk about cementing everything out but then what do you do with the liquid. Can you pour them down the drain.'what about the solids? Can you throw them in the trash.is there a company where I can just take this stuff to and drop it off? I know this is a lot of question but I'm sure I'm not the only one that needs these answers. I will be very grateful to anybody that can help me with these questions
 
Well I'd be tempted to mix the solutions and add a copper bar to recover any traces of values, your stannous test should tell you if any values remain, but just to be ultra cautious I'd still run them through the cementation stage. After they have sat for a day or so you can pour them into a tub that has steel in to cement the copper out again allow several days then pour this into another tub and add lye and all other metals should drop out of solution as you get into an alkaline state. This liquid should be safe to pour away and all the solids once rinsed and dried can be put in the trash.
 
I personally do mix them together in 5 gallons buckets and cement everything with scrap steel.
I have an already very rusty shed, that's where i keep the buckets.
You can keep yours out side, coverd but not sealed. Make sure you prevent access from pets and kids and mark POISON on or above them.

When cementation is done (in my case, when the bucket is full and at least a week has gone by with scrap steel inside), i pour the majority of the solution to another bucket and rise pH with lye to about 7, then discard.

I keep all the cemented material (which is mostly Cu) for further recovery as it may very well contains traces of: Ag,Au,Pt and Pd + bits of of steel.

All of my acidic waste solutions goes to the same bucket; either nitrate, chlorides or sulfates.
 
So after cementing and raising the ph with lie I can just pour the acid down the drain or stormdrain and throw the solids in the trash. And nobody will get sick?
 
croakersoaker said:
So after cementing and raising the ph with lie I can just pour the acid down the drain or stormdrain and throw the solids in the trash. And nobody will get sick?

GoldSilverPro discusses this at great length, from the business/municipal/EPA point of view, under "The Elephant in the Room". Use your search button.

Now, this is just me, and not meant to be any reflection on you and your experience/professionalism. Plus, I really appreciate the mark of responsibility you display by digging into this; however:

I fear that your lack of questions at this point means that you'll shortcut the process somehow, oversimplifying it, thus failing to carry out complete cementation, and poisoning us all. :shock:

You did notice that there are usually 2 steps to cementation, unless you just drop EVERYTHING with steel, like samuel-a, & save the residue for later processing? Processing out the base metals & safely disposing of them sounds easy on paper, but can be a real b***h in practice, catching you in an endless daisy-chain of cementing, straining, decanting, etc. until you get the hang of it, which can make the shortcut thing seem real tempting.

Ph is also important here - GSP's post explains why - and it takes surprisingly more lye to do the trick than one might at first imagine.

I realize that I'm probably being over protective (For the kids' sake - Thank G*d I didn't have any - they'd hate me, I'm sure) but I like to measure it twice and cut it once.

Just be cautious & make sure you've educated yourself sufficiently.

Just my dos centavos.
dtectr

P.S. And, "Yes", I do where a belt and suspenders! :lol:
d
 
Thanks and I do want to be responsible I live in a neighbOrhood and I have a two year old and three dogs.which is why I asked for a step by step. I don't want to leave any thing out. Don't want to hurt myself, my family or anybody elses. I'll be just dealing with small amounts but if it doesn't cost to much I'd still rather drop it off with a hazordous waste disposal company but I'm sure that's not efficient,although i do live
In a big city ( Houston ) so maybe there is a comPany that's takes this stuff
 
No, you can do it, man - just don't get in too much of a hurry as you do so. 8)
I was afraid I'd discourage you from trying. That wasn't my intention. But the fact that you're concerned tells me what I wanted to know - you're checking your P's and Q's before you jump in & thats a good thing! :) On our scale, it would take the profit out of it to pay someone to do what we can do ourselves.

Look up that thread started by GoldSilverPro - it really gives us an inside look from Big Brother's point of view, and lets us know what to consider.

Do your searches, follow the voices of experience (I'm still VERY new at this), and you'll do fine.
 
hello i have been doing some refining and have nitric acid wastes.
i have put the acid into a drum with steel where the copper pieces cemented out. then i have put lye/ caustic soda to neutralize the solution to 7 ph. my question is that there is a muddy substance which settles in the solution... there is too much of this muddy substance at the bottom.
 
Raising the pH to 7 directly on a solution is not enough to remove all of the base metals as many base metal hydroxides are soluble at pH 7. Personally I raise the pH to 9.5 filter the sludge out, then neutralize to pH 7. What remains is salt water (sodium sulfate and sodium chloride) that can be disposed of via dehydration and disposal of the salt at the dump or the liquid can be taken to a waste water treatment plant that will accept the liquid. It would be wise to have the clear waste water tested first before deciding on a disposal route. The sludge is taken to the local landfill and given to the HHW (household hazardous waste) manger who stores it in a lined steel drum and has it hauled off when full for a fee. I pay $330 to have a single 55 gallon drum disposed of in this fashion. This cost does not include the cost of lye, waste disposal containers, labor, and PPE (personal protective equipment) on my end.

Here's a few posts and text that discuss the solubility of various base metal hydroxides:

Various Precipitation pH's of Base Metals

Hydroxide Solubility Curves

More On removing Metals from Solutions

Using lime is cheaper than sodium hydroxide (lye), but it's much less soluble in water and necessarily increases the volume of your waste solution for this reason. If you use a steel that contains chromium to cement the copper from the solution, you will be adding chrome ions to the solution as iron does not cement chromium. If you do not completely saturate the solution with iron, there is no guarantee that you have removed all of the other base metals from the solution. If you use junk steel that is painted or has coatings, or if you processed circuit board material and/or components with your solutions, they may contain organic compounds which complex with some metals, which can prevent normally cemented metals from precipitating on iron. If you have large excess of free acid in the solution, it can dissolve multiple metals on the activity series chart simultaneously in the same solution without precipitation.

If you choose to collect the copper from the iron only cementation, be aware that it may very well contain other dangerous metals such as arsenic (common dopant in integrated circuits and components), barium (found in surface mounted capacitors and components), cadmium, antimony, lead, nickel, mercury, and cobalt. Several of these metals produce dangerous gases when heated (eg.: when melting the copper).

If you have a known type of clean steel and know your solution only contains copper and nickel, then you should be alright simply using iron cemetation to saturation and raising the pH to 7.

As I mentioned before, if you have ammonia in your waste solution, you will likely produce a choking ammonia and/or ammonium chloride vapors when neutralizing the solution.

Know your scrap, reagents, and wastes.

Steve
 
Woody1960
Look through the forum there are many posts on this complete with pictures and discussions.
You will find much more information there, than from getting a few answers to a question.
 
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