Dealing with Waste

[nickvc]

I'm sure you are probably right about some people just dumping their waste into the drains but with it will come back on them at some point, we do have conversations about correct disposal of our wastes on various threads and all the senior members stress that it is very important to treat them properly, it takes time and effort but is cheaper than been caught dumping toxic waste and getting caught not to mention the morality of it, if you spend a few minutes every day or week processing the wastes it helps them to flow more easily especially if your processing values regularly.

 

[kurtak]

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.

Per the above underlined - I am very glad to hear your attitude on this autumnwillow - it shows good moral principle & practice on your part 8) :!:

Kurt

 

[autumnwillow]

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

I've been reading that thread, its a very nice idea. I think this could be a substitute for a stock pot. Though the end product is still ferric chloride, it would be minimized because you do not need to introduce any more metals for the recovery. Very interesting. Would you video it and show us how it works?

 

[Anonymous]

A note that is important.

If you use this cell for recovery of metals from AR waste or any solution containing HCl you WILL generate Chlorine gas. Therefore your extraction system needs to be of the correct specification to handle this. It's no deal breaker, you just need to be equipped correctly.

Jon

 

[nickvc]

A note that is important.

If you use this cell for recovery of metals from AR waste or any solution containing HCl you WILL generate Chlorine gas. Therefore your extraction system needs to be of the correct specification to handle this. It's no deal breaker, you just need to be equipped correctly.

Jon

I'm impressed Jon, well done 8)

 

[Tndavid]

I am a chemist and I've been around precious metals both analytically and for recovery since 1972. I built a small "refinery" for a manufacturer I was working for at my first job out of college, they were getting ripped off by their refiner and I proved to them how much I could save them by processing the higher yield materials in house. They allotted me a space roughly 15 by 20 with 2 hoods which entered the facility's scrubbed exhaust from the plating shop. I also had a drain for acid waste and one for cyanide. Both were treated before discharge. In that room I recovered the gold and made it into PGC (potassium gold cyanide) a salt used in gold electroplating. After my first year I had recovered over 400 ounces of gold from the higher yield materials, and shipped out the low grade materials, which I witnessed myself. The return we received from the low grade, equaled the previous history for returns when they shipped all of the material out and didn't send a rep. I left that company after 5 years and went to another large manufacturer who also had a plating facility, I basically did the same thing for them, only we sold the fine gold instead of making gold salts. After 3 years at the new place I heard that they fired the guy who replaced me at the first place because he wasn't getting the same results as me and they eventually caught him stealing. (Ironically they had hired him from a local refiner because of his work experience) They made me an offer to open my own refinery to process their materials, I approached my current boss at the time and he said if I took them up on their offer, he would send me all of their work as well.

So now I had my own refinery, a 950 square foot facility with 2 good customers to cover my overhead. The first few years were difficult because I was adding equipment to refine faster and smarter but when I settled down on a stream of work, I did very well. I ran that place for 10 years, had 6 employees and sold it for a tidy sum. They had a fire about 6 years later, they had expanded and never took the time to set up a proper chemical storage area, after the fire department left it became a superfund cleanup site.

I had moved on to consulting, basically setting up refineries either completely from scratch or adding process capabilities to suit the owners needs. I semi retired in 1990 just handling 1 client at a time and have done that since. I've handled alot of jewelry related materials, silver and PGM refining, setting up assay labs, electronic scrap processing and even had a placer operation going in Brazil for a few years, with its own refinery of course. Of late the biggest headache for refiners is the EPA and all of my clients are compliant and usually pass inspections.

Very nice. Thanks for sharing...

 

[IdahoMole]

I am ready (I think) to dispose of some of my waste and I want to get this right. I have three glass cookie jars that I am using, one with copper(#1), one with iron (#2), and the third for settling (#3).
Over the last 10 days I have raised the ph of jar #2 to 3 and the ph of jar #3 to 11 using lye. Jar #3 has settled nicely. Here is a picture.

Is the clear liquid in the jar ready to be siphoned into a bucket, the ph adjusted to 7, and discarded down the drain? Can I filter the remaining liquid from the solids, dry the solids, and throw them away? Am I missing anything?

 

[Grelko]

Over the last 10 days I have raised the ph of jar #2 to 3 and the ph of jar #3 to 11 using lye.

Edit - There are a few more threads that say to bring the solution to 9 or 9.5, then back to 7. I was looking for the one named (what should I do with leftover ap) or something, but I couldn't seem to find it.

You can always double check, just incase something re-dissolved, since you brought it up to PH 11.

Took me over an hour to remember where this link was hiding at, but the information in there is worth finding.

http://goldrefiningforum.com/phpBB3/viewtopic.php?f=37&t=1946&p=243417#p243417

It should be noted that precipitating metals from solutions as hydroxides is not an "exact" science - the numbers provided by Steve are the "optimum" numbers for each metal but in reality hydroxides of each metal will "start to form (drop out) at lower Ph numbers then there listed "optimum" number - meaning hydroxide precipitation occurs within a "range" both above & below that of the listed "optimum" number - also some metals will re-dissolve when the go beyond the high end of the "range" with in which they will precipitate

Kurt

 

[IdahoMole]

Thank you grelko. I'll bring the ph to 9.5-10 and leave it for a day before proceeding.
The ph obviously started quite low and I have been adding 100 grams of NaOH (lye) daily. The ph was slow to change but when it hit ph5 the 100g of NaOH took it all the way to 11. I knew that the closer to neutral I got the faster it is to change. I am keeping notes and it will get easier with experience.

 

[Grelko]

You should at least be able to filter out the solids and dry them, but I'm not completely sure if there would be anything still dissolved in the clear liquid. I've had solutions with a higher PH that were clear and still contained metals.

Other members would be able to help you a lot better and let you know if you are able to throw away the solids yet. You may need to heat it to a red glow, to turn certain metals into oxides etc.

I evaporate most of my solutions, so I haven't completely gone through the waste disposal yet.

 

[MrCrusher]

Well I thought even though this is an old thread my question belonged here.
If there is a better place to ask this any moderator can feel free to move it.

I am working with Silver ATM and I prefer to convert my dissolved silver back to metal using.

Salt then rinse then use the Lye and Sugar.
I know I can drop using copper I just prefer this method.

My question is can I use the sugar lye waste water in treating my other waste when it is time to drop the iron? Basically I want to get as much from my lye as I can or will the sugar cause issues? I know this will add to the volume but it may be better then just neutralizing and disposal.

Any insight is always appreciated.

Thanx
Mr_Crusher

 

[butcher]

AgNO₃ + NaCl --> AgCl_(s) + NaNO₃
The byproduct NaNO₃ can be reused.

2AgCl + 3NaOH + C₆H₁₂O₆
-->
2Ag + 2NaCl + C₆H₁₁O₇Na +H2O


saltwater and sodium gluconate I treat this waste separately. I like to keep it inorganic and organic (carbon-based waste separate where possible.

Then again I find Many uses for what others call waste, much of it I consider byproducts that can be reused.

https://en.wikipedia.org/wiki/Sodium_gluconate

 

[Rougemillenial]

i usually use aluminium as the reducing agent. The reaction is cooled with a water bath laced with soda ash in case of a boil over. I use the acid process to recover metals and because i don't use nitric, the amount of waste is greater due to AP not being that efficient. the aluminum is rather good at reducing stuff as the exotherm pushes the reaction forward. then the sludge remaining is allowed to settle and I decant the aluminium salts into another container. then because i live in an area with good disposal services, I simply fill up water bottles and milk jugs with the solution and put it in the garbage. Even though I'm sure there's a better way, it works fine for me. As of right now, I've been trying to get everything done in two or three weeks because of bigger fish needing some frying. I'm in the northeast US where it's quite populated so I have to keep good terms with neighbors which can be rather tricky when something inevitably goes wrong. though that's beside the point. I do have a large scale operation. 2 metric ton scale to be exact. I've been able to get it down to 600lbs over three years of incineration and AP. As for cyanide, your best bet is to use bleach to precipitate the gold and kill the cyanide solution. Also wastes that can't be reduced with aluminium should be neutralized with soda ash since you can save nitrate ions as sodium nitrate while dropping the transition metals as the corresponding carbonate or hydroxide. aluminum does not react with nitric acid or nitrates unless gallium or mercury is present as a catalyst.

 

[butcher]

What works for you is putting others in Danger.
Rougemillenial, You should spend your time studying waste disposal, and the forum, much of your posts to me seem to be coming from someone who has done a lot of research (study) but really has very little understanding.

It is not what you think you know. when you think or believe you know it (when you really do not understand). Thinking you know something can be dangerous.

it is when you know, and you understand that you really do not know or understand, that you can truly learn and come to a true understanding and knowledge because when we realize we do not know we can continue to study and gain knowledge.Then you can truly share knowledgeable information of what you actually do know.

From what I read from your posts, is you believe you know (What I see in your writing is you have done some study, but you do not know or understand as much as you think you do, and you do not understand and at this point spouting a lot of misinformation in your poorly misguided state of mind, your filling your posts unknowingly with wrong ideas methods and just plain misinformation on the forum, which for those members trying to learn to do this correctly, if they read your post they will then become even more misguided than you are, as you spouting off of pure nonsense from your misguded thoughts will not only make things more difficult but also put them in danger.



I suggest you take what you know, and use it to learn more, and to gain that understanding you seem to lack now.

Some of your posts are full of misconceptions, your post above is not only misinformation but just plain dangerous.
Stop trying to show us what you know it is only proving what you do not understand.
and spend your time gaining that knowledge (you falsely think you have already).

I am found much of your posting as misguided and spouting misinformation annoying, now I am seeing it as just plain dangerous.

 

[Rougemillenial]

What works for you is putting others in Danger.
Rougemillenial, You should spend your time studying waste disposal, and the forum, much of your posts to me seem to be coming from someone who has done a lot of research (study) but really has very little understanding.

It is not what you think you know. when you think or believe you know it (when you really do not understand). Thinking you know something can be dangerous.

it is when you know, and you understand that you really do not know or understand, that you can truly learn and come to a true understanding and knowledge because when we realize we do not know we can continue to study and gain knowledge.Then you can truly share knowledgeable information of what you actually do know.

From what I read from your posts, is you believe you know (What I see in your writing is you have done some study, but you do not know or understand as much as you think you do, and you do not understand and at this point spouting a lot of misinformation in your poorly misguided state of mind, your filling your posts unknowingly with wrong ideas methods and just plain misinformation on the forum, which for those members trying to learn to do this correctly, if they read your post they will then become even more misguided than you are, as you spouting off of pure nonsense from your misguded thoughts will not only make things more difficult but also put them in danger.



I suggest you take what you know, and use it to learn more, and to gain that understanding you seem to lack now.

Some of your posts are full of misconceptions, your post above is not only misinformation but just plain dangerous.
Stop trying to show us what you know it is only proving what you do not understand.
and spend your time gaining that knowledge (you falsely think you have already).

I am found much of your posting as misguided and spouting misinformation annoying, now I am seeing it as just plain dangerous.

Ok

 

[butcher]

C.M. Hoke's Book, Refining precious metal wastes--written by a chemist ( a really pretty chemist), extremely ahead of her time in life, as well as chemistry, her knowledge of chemistry I strongly suspect would easily overwhelm most chemist our schools put out with honor roll grades or even years in a field of work. She wrote her book for chemist and nonchemist alike.

She understood more about metallurgy than most chemist today, but she could also teach it to a jeweler.
Now that is something special, smart enough to speak in a Layman's terminology and get the knowledge across to those who can grasp what she is teaching of complex chemistry in simple terms and concepts (that you may have to read the book several times to grasp), but one you do you can put most of the equations, and other chemical equations together with other sources of study.
something simple like how she gives a formula for how much acids are needed to dissolve gold, when you study it, and use chemical formulas and equations you begin to see how much she could teach and spell out the chemical formulas (in layman's terminology) with very little words or deep complex explanations, but when you begin to see the complexity it makes you also appreciate the simple down to earth knowledge contained within.

If you do not see the magic then you haven't read enough of her book.

 

[Slochteren]

The weather here is getting a bit better/warmer so i can clean up my waste i collected over winter. I have a few buckets with rinse water from cleaning silver. The ph is between 4 and 6, what is the best way to lower the ph to 2,5 to cement out the copper on iron?

Thx Paul

 

[butcher]

You can add an acid to lower the pH. Then to replace the copper ions (reducing copper ions in solution to metal atoms of copper) with iron metal where the iron metal gives up electrons (oxidized) to the copper ions, where iron replaces the copper, and metals below copper in the reactivity series of metals.

https://en.wikipedia.org/wiki/Reactivity_series


If you do not have any metals worth recovery, and you are just treating waste, you can precipitate metals as hydroxides following the instructions of dealing with waste.

Note not all metals precipitate as hydroxides at the same pH, this has been accounted for in the instructions of dealing with waste.

 

[upcyclist]

You can add an acid to lower the pH.

Note that you can either add 'virgin' acid (sticking to the cheap stuff like HCl), or since it's warmer and you're processing more, add it to your fresher waste acid until your pH is close to 2.5. In other words, add as much as you can to your new stream without raising the pH too high.

I also like butcher's point about worrying about metals worth recovery--since your pH may be pretty high (5 or 6?) by now, it could be simpler to just skip the copper cementation on iron and head to the next step of raising it above 7. If you were cleaning silver converted from AgCl, there's not a lot of copper in there. If you were cleaning cement silver, there is a lot of copper

 

[Yggdrasil]

Hi!
Just to follow up with a few question about this, since I now have reached a level,
where I have soon to finalize my waste for disposal.

It seem any hydroxide will do the job and 4Metals recommend MgOH due to easier "settling".
My regular supplier don't have that ready, but will KOH be better than NaOH in that respect?
All the my small batches that has been treated with NaOH seems to "never" settle completely.
Or just ask if my supplier can acquire it from their supplier, might end up as the best solution. :wink: