can capture gold ions from computer motherboards bathed in acid.
I think you need aqua regia (hydrochloric and nitric acid) to ionize gold in solution. They say pH of 3. The sponge is just the ionic deposition media for the solution. The fumes from copper reacting with nitric acid are dangerous, as is the acid reagent. It doesn't sound clearly safer than cyanide which works for microscopic gold particles. They definitely are not wiping the gold off with a sponge.
Electronics recycling is a tough business and I think that they have a way to go to make this work.
>can capture gold ions from computer motherboards bathed in acid.
I think you need aqua regia (hydrochloric and nitric acid) to ionize gold in solution. They say pH of 3. The sponge is just the ionic deposition media for the solution. The fumes from copper reacting with nitric acid are dangerous, as is the acid reagent. It doesn't sound clearly safer than cyanide which works for microscopic gold particles. They definitely are not wiping the gold off with a sponge.
Electronics recycling is a tough business and I think that they have a way to go to make this work.