Gold in sludge

[worker0]

Helo friends,

Today I filtered my gold from gold plated connectors and pins from RJ45. Booth is industrial type of equiepment. I was doing nitric wash. I stired jar with connectors to "lift up" sludge to test it will it pass throught filter, and they pased without any problems. When I finished nitric wash I filtered solution ( attemped ) to large bucker covered with silk mesh. On picrures is what I get.
What to do???

 

[Geo]

Metastannic acid or hydrated tin oxide. Place the mass in a container, a beaker is best. Add water to 1/2 the containers volume. Add sodium hydroxide slowly while stirring. The solution should get very hot so be careful to stop adding and let the beaker cool periodically. When there is no more reaction when a little more is added, slowly dilute with water. move to a larger container if you need to. Add water unto the solution is murky but semi-clear. Any solids will settle quickly. Decant the clear solution and discard. Repeat the water rinse. When the water is decanted the second time, start adding dilute HCl. 10% of what you have and 90% water. Add and stir. The solution will turn green and some of the mass will dissolve each addition. Add up to 1000ml of acid diluted with water in this way and let it sit over night. Slowly decant the solution into another container careful not to disturb any solids in the bottom. To the last bit of solids, add HCl full strength in small increments until no more solids will dissolve. You should be left with gold foils and very little of anything else.

 

[anachronism]

Metastannic acid or hydrated tin oxide. Place the mass in a container, a beaker is best. Add water to 1/2 the containers volume. Add sodium hydroxide slowly while stirring. The solution should get very hot so be careful to stop adding and let the beaker cool periodically. When there is no more reaction when a little more is added, slowly dilute with water. move to a larger container if you need to. Add water unto the solution is murky but semi-clear. Any solids will settle quickly. Decant the clear solution and discard. Repeat the water rinse. When the water is decanted the second time, start adding dilute HCl. 10% of what you have and 90% water. Add and stir. The solution will turn green and some of the mass will dissolve each addition. Add up to 1000ml of acid diluted with water in this way and let it sit over night. Slowly decant the solution into another container careful not to disturb any solids in the bottom. To the last bit of solids, add HCl full strength in small increments until no more solids will dissolve. You should be left with gold foils and very little of anything else.

Isn't that an enormous amount of waste liquid?

 

[worker0]

I can not buy NaOH, can I use Urea or natrium bicarbonate, or CaO?

 

[Geo]

Isn't that an enormous amount of waste liquid?

It is. It is the easiest though, in my opinion. Veterans knows to avoid making it to begin with. Maybe with some more practice and experience, he can avoid it in the future. Learning how to deal with waste is important too.

 

[Geo]

I can not buy NaOH, can I use Urea or natrium bicarbonate, or CaO?

Not sure about the carbonate. I have have only ever used NaOH. Do you have access to chlorine bleach? If so, boiling chlorine bleach (not simply evaporating) produces NaOH crystals. The better way to produce NaOH is through electrolysing chlorine bleach in a simple cell.

 

[worker0]

What about Urea? I will try natrium bicarbobate. Will repport.

EDIT: Problem solved.