Gold Troubles

I had some gold the other day in powder form, after dropping it out of a auric chloride (Gold (III) Chloride) solution, but it didn't amount to much of anything. The auric chloride solution I dropped the gold from only contained a small amount gold which came from some gold flakes I had laying around. The majority of the gold I had was in another auric chloride solution, but I could not get the gold to fall out of this solution with sodium metabisulfite.

Sodium metabisulfite is suppose to drop the gold from the auric chloride and create salt (sodium chloride) and sulfur dioxide gas. I found if the chlorine level is too high in the auric chloride solution then this reaction will not take place. Of course, I found this out after I already tried to make the gold fall out with a different method. I decided to use copper, instead of the sodium metabisulfite, to drop the gold. Copper has a lower electronegativity than does gold and this allows copper to more easily give up electrons. Having copper give up electrons more easily makes the formation of copper chloride more favorable than gold chloride. This is the same principle behind sodium metabisulfite. The formation of sodium chloride is a favorable reactions, so it will occur.

Anyway, I basically stuck a copper pipe in the jug with my stubborn gold chloride solution and hoped the gold would fall out or collect on the pipe. I believe this did happen at first, but because there was a large amount of hydrochloric acid still present in the solution the pipe started to dissolve more than I anticipated.  This caused large amounts of copper to mix in to the solution and contaminate the gold.

After scraping the black coating of copper and gold off the pipe I dissolved it again in another solution of hydrochloric acid and hydrogen peroxide. I was hopping that I would be able to just dissolve this copper, as the solution is intended to do. But, because I had so little gold and copper, both were dissolved. I haven't touched the liquid in a few days now.

This is all a bit confusing reading over this again. I wish I had my camera to take a few pictures of the mess, but I still haven't had it returned to me.

Here's a list of the liquids I have:

• A small, light green colored, beaker filled with the HCl (hydrogen chloride acid) and the H2O2 (Hydrogen Peroxide) with the black flakes of copper and gold from the copper pipe
• A medium, light yellow colored, beaker with the gold powder dissolved in HCl and NaClO (Bleach). This is a gold chloride solution
• A 2 liter jug of dark yellow brown, almost black, liquid which was once gold chloride with sodium metabisulfite. The copper pipe change the color to this dark color. Normally when copper is dissolved it turns green when a copper chloride solution is formed. A solution like the one in my small beaker mentioned above

The Beginning

I have started a new hobby and decided that I needed to keep track of what I am doing. I thought about just writing it down in a lab notebook, but notebooks get lost and I spend a great deal of time in front of my computer. I can also tie this in with a blogging assignment for one of my classes this semester.

The other day I was thinking about solar panels and the process of making solar panels. I had been reading about the regular silicon solar cells and the newer dye-sensitized solar cells. I was thinking it would be fun to try and build a solar cell or at least do some research about solar cell design. In my research I was reading about how they worked and what they contained. I began to think about the Silicon they contain and where I might be able to find a cheap or free source. I begin to wonder if you could, some how, extract the silicon out of old computer parts. Recycle the old computers for the silicon and create solar panels. It seemed easy enough. Right?

I started to read about the materials contained in the circuit boards, found in many and most electronics. I knew that some amount of silicon could be found on these boards in the form of silicon chips. As I read more about these boards I can to understand that there were many precious metals, such as gold, silver, and copper, contained in the circuitry and connectors. So, my focus shifted away from building solar cells towards recycling.

This is what led me to my current hobby. I though, instead of trying to recycle the boards for the silicon, I could recycle the boards for their metals. I had a half dozen computer sitting in my basement that were too old to do anything useful and thought this would be a fun way to get something out of them.

I came to find out that many people, both individuals and commercial companies, do this on a large scale. I was able found some general information on a few good forums and decided to try my hand at these processes. So far, I have had mixed results. I know the contents of some of the liquids I have and what they are, but I am unsure if what I am getting out of these liquids is actually what I want. I am hoping that someone will see this and will be able to guide in the right direction. I plan on positing some pictures and more posts on what I have done so far.