Wastes - The Elephant in the Room

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I've heard that Titainium is used in electrolytic cells in submarines to produce extra oxygen for the crew. So it should take the strain of being a good anode.
 
Harold_V said:
james122964 said:
Well plated out some copper. I did better than the first time but was still very spongy. Also, I use SS for my anode and it dissolved contaminating my solution.
My anode was comprised of gold alloy and copper, which worked well aside from the spongy deposit. That seems to be a common problem, and was enough to discourage me from any further attempts, considering my purpose was to gather the slimes for further processing. I kow this is an old topic but i wondered if you had problems with the sponge in your wastes would an annode bag not catch all the slimes? i used this method in a silver cell to catch the gold contaminants any sludge at the bottom of the cell should be copper or in my case silver...
 
Im jumping the gun here becuase I havent done my research.

What about something like "T-6" (i think its called) sold by gold mine world?

Its actual use is at sewer treatment plants to drop out ALL metals into a sludge, i think. Its supposed to be fast too. I have found it for sale at other places, but not much cheaper than goldmineworld.

there was some posts on this forum about these precipitants as well.

just my thoughts

Ryan
 
Thanks.
I saved that pdf for reference. I never new of any of the treatment plants around here using Thio-red, but they do use alum as a flocculant and it's reasonably cost effective to use.
dickb
 
This is precisely the reason I no longer refine boards or fingers. I feel the contaminates left over are just too bad. I called our local PCA a while back, got a voice message, called back again and got nothing but attitude from the Receptionists. (Our MN tax dollars at work..!) In my state this Government office is huge with little accountability.)

None of the local Refineries where I sell my boards will take my contaminates w/o an EPA #, Infact it seems as if they discourage my works. Now I just cut off the fingers, and sell them separately to the refinery, I actually get a good price for them and I know that the contaminates are properly cleaned up.

I know a guy who refines a pretty good amount of fingers on a regular basis due to the amount of PC scrap he has access to. I asked him what he does with his green waste, He smiled and said "I know a Bush that likes it". At first I thought this was a little humorous, then I thought about the watershed he lives in and how the City well is really not that far away from his residence.

I would never encourage or teach anyone how to refine circuit boards.!
 
Lou said:
I've used sodium borohydride many, many times. It's a very good reducing agent that only slowly reacts with water and primary alcohols (destroyed in a few hours' time, it is hygroscopic as well). It is used very much in organic chemistry as it is a clean, mild reductant and is much safer than lithium aluminum hydride which is pyrophoric. Many hydrides are becoming cheaper as they have potential use for storing hydrogen.
Borohydride is nice, agreeable stuff for reducing platinum quickly and selectively, but it's expensive. Cheapest I've ever seen it was about $500 USD for 5 kilograms.

A bump I know but... say I wanted to give sodium borohydride a whirl. What is the procedure to drop metals? Is it as easy as dropping gold with smb? Being that it's hygroscopic I would think so. I'd like to get a small batch of 100 grams to process a bunch of Pd/Pt scrap I've been sitting on for a very long time now. Where would be the cheapest place to get this 4 years later?

Lou said:
Still, there are other reducers that work just as well and better.I find that the ammonium formate route works well though, and gives a clean product...

The salts are easier to work with though, and can be made very cheaply (about $15/kilogram), if anyone wants to know how, just ask.

Was Lou talking about making ammonium formate? Because if he was I'm askin. Where could I find it and what would be the procedure for ppt?
 
Morning All – I am currently working on the waste stream, I to believe in full recycling, or as close as I can get.

The method so far goes like this:

My waste consists of base metals, firstly the waste is put into small 2lt containers along with granulated copper, this form of copper works well, large surface area, and precious metals will drop, and the container is shaken periodically. After 24hr the finally divided precipitates are filtered after being put into suspended solution by shaking. The copper stays on the bottom and is shinny after the strip is complete.

Stage two, the waste is transferred to another 2lt where an iron bar is placed, occasional shacking and in 24hr the solution has gone from darkish blue/green/brown to green. The waste is filtered to obtain copper and anything else below the reactivity scale for iron and forms a stable precipitate.

Stage three, yet again the waste is transferred to another 2lt container in which aluminium foil is added from pyrolized electrolytic capacitors. This will take time, especially if the pH starts to creep up and the remaining acid is consumed. The solution is almost clear at this stage, with a slight greyish look after filtering. I need to do a little bit more work, finding out what is in the filter cake.

Now for the forth stage, this still needs to manifest itself but will any luck it will go like this, aluminium chloride hexahydrate is the main contaminant along with any unstable aqueous metals that aluminium cannot precipitate. I intend to evaporated this solution until the aluminium chloride hexahydrate starts to becomes volatile releasing HCl for reuse.

Forgot to mention the Iron contaminant :roll:

Well that’s my theory so far. I am at the filtering stage of the aluminium drop of precipitable metals.

Any constructive thoughts on the last portion of the process will be muchly appreciated.


Regards

Deano
 
Aluminum works well, but the slimmy stuff takes ages to dry,heat helps.

How would you get HCl from this? Aluminum gives off Hydrogen as gas when it dissolves, so where is the Hydrogen going to come from to make Hydrogen chloride from the aluminum chloride salts? are you useing the hydrogen from that first reaction (dissolving the aluminum) somehow?
 
Hi Butcher, From Wiki – “Hydrated aluminium trichloride is prepared by dissolving aluminium oxides in hydrochloric acid. Heating this solid does not produce anhydrous aluminium trichloride, the hexahydrate decomposes to aluminium oxide when heated to 300 °C:[4] 2 AlCl3 + 3 H2O → Al2O3 + 6 HCl”

The hexahydrate is also formed when aluminium reacts with metal chorides in solution below aluminiums reactivity. As for hydrogen, it is not the reductant, it's the exposed aluminium after the oxide is dissolved by the HCl


I have about 1.5kg of the anhydrous AlCl3 that I can experiment with, and this is very nasty stuff, evolves HCl when exposed to any form of moisture.

Cheers

Deano
 
So if I understand this, the water in the reaction with AlCl3 provides the hydrogen, giving an oxide of aluminum and Hydrochloric acid?

Aluminum is above hydrogen in the reactivity series’ of metals but I did not realize it would split or disassociate the water (or its salts), (I know some of the very reactive metals would but they usually form metal hydroxides), and that this AlCl3 is not elemental aluminum and where metal aluminum may not split water is it something about its chloride or is it the 300 degree heat a major part of this reaction, or combination of both ?

I am not a chemist, but sure like to learn what I can about how these things react, sometimes the language you chemist use is above my vocabulary list.

Ya know how us hillbilly's R bout talkin.

The HCl I presume would be a gas and need to be bubbled into water?

This would be a good way to deal with the aluminum slime,

Thanks.
 
Hi Butcher, I think the process is called thermal decomposition, degradation or something like that, heat anything hot enough, break the associated bond energy’s, thus allowing them to reform into more stable compounds. With organic compounds, covalent rather than ionic bonds are broken; the reforming of molecules or elements can be rather random due to free radicals produced as a result of high temperatures.

Aluminium Chloride Hexahydrate = AlCl3.6H2O The water molecules supply’s the oxygen for the formation of Al2O3 and the hydrogen for the HCl.

And yes, the HCl needs to be cooled first and then bubbled through water, colder the better, using a bubbler inside an inverted funnel works well to.

Copper oxide which is an unwanted product from the iron drop of the rich copper waste solutions, caused by oxidation during drying, will be reduced using hydrogen, generated by the reaction of aluminium with NaOH, drying the hydrogen through concentrated sulphuric acid. The copper oxide is heated to above 500deg C. and then the dry hydrogen introduced, product? - Copper powder, water and possibly some un-reacted hydrogen.

This is sort of the reverse when it comes to removing Oxygen from air. Pass air over/through finely divided copper above 500deg C. and copper is oxidised, resulting in an Oxygen free gas.

Hope this sort of helps, I do ramble now and then. :roll:

Cheers

Deano

Please Note: Due Not under any circumstances perform hydrogen production, using aluminium and NaOH, in a glass vessel in the sun or bright light. Unwanted by-products of this reaction, formed by impurities within both the aluminium and the NaOH, mainly Chlorine, will react violently and may cause an explosion. Be Warned.
 
im sorry i will wrote in french because ,it is very hard for me right now to explain myself in english on this subject.

ce que je veut dire ,c'est que la solution a notre probleme n'est peu etre pas celle que nous croyons, nous cherchons un moyen de se departir de nos dechet de facon economique et nous finissons par envoyer nos dechet de facon illegal a la poubelle mais si nous cherchions des produits qui sont utilisable a plusieur reprise. a titre dexemple (personnellement je ne lai pas encore utiliser)lacide peroxique reoxigener, qui selon plusieur ici est utilisable a repetition avec lajout dun bulleur a poisson.il en revien donc beaucoup moin cher de sens departir legalement etant donner que les cout sont amortis sur plusieur batch.
peu etre devrions nous chercher a rentabiliser nos produit plutot que de sens departir a moindre cout.

sinon il y a la posssibiliter de changer nos produit pour finir avec des truc bon pour lenvironnement ex: le sulfate de cuivre
si au lieu dutiliser de lacide peroxique pour retirer les doigt de carte nous utilisons de lacide nitric ,le residue qui se fais est du nitrate de cuivre, ce meme nitrate de cuivre peut etre reconvertit en acide nitric avec comme produit residuel du sulfate de cuivre qui si je ne me trompe pas est un engrais courant...
 

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