2024年11月18日 · In the process of gold recovery using the aqua regia method, after leaching gold from e-waste, we proceed to neutralize the solution using urea. Following neutralization, we add sodium metabisulfite (SMBS) to precipitate gold dust. However, I have encountered an issue: if an excess amount of SMBS is added to the solution, white precipitates form.

2011年11月7日 · The green is from base metals, they needed to be eliminated before using aqua regia on gold; then your gold chloride solution would be yellow. You can also learn not to use too much nitric when dissolving in aqua regia, GSP has made some very good posts on the subject.

2022年2月10日 · Please, advise the best method to precipitate a maximum percent of PGM from Aqua Regia solution. Now I work with rich sulfide ore concentrate with PGM at about 800 gr/ton (mainly Pt, Ag, Au). I have to use Aqua Regia (AR) 30% as a dissolver because of its high oxidizing potential compared to other methods like direct chlorination or cyanides.

2014年3月16日 · We put our aqua regia jar into the water. I then added the acids. I got a initial strong reaction. Which then rapidly dissipated to a very slow reaction. As the reaction slowed we added more warm water. To clarify we wanted to use a flame to heat the water under the regia. With the regia being raised off of the boiling water.

2007年4月14日 · I'm one of those idiots or morons that uses aqua regia as a primary recovery step. Its the fastest way I've found to recover gold from board fingers and ceramic cpus, which is mostly the material I deal with. My method is to dilute the acid with a two to one ratio of hot water after the gold bearing material has dissolved.

2024年6月9日 · The remaining 3 feet of the hood is for aqua regia digestions specifically for ICP work. In an effort to prevent the HCl fumes from aqua regia effecting the parting, the exhaust for the NOx reactions is drawn off the left side of the hood so the aqua regia fumes never have to pass over the parting side which is on the right. View attachment 63242

2010年7月30日 · OK this is my story I made aqua regia using the sodium nitrate/meuratic acid method and proceeded to dissolve about a pound of gold plated pins fingers and chips while capturing the fumes in several 1 gallon glass jars and reacting that with water to reclaim the valuable nitric acid. After the...

2007年3月30日 · Aqua Regia is about the only method, for the small refiner, to purify gold to 999.9 Fine - no matter what anyone says. Not only does this method work on most karat golds, it is also the final re-fining step that is used to purify the gold collected from all types of scrap.

2020年6月28日 · I am quite comfortable testing small samples of concentrates for gold using aqua regia dissolution and stannous chloride test. This requires only a few mls of acid. Today, I encountered a new twist, concentrates that appear to test positive for platinum with stannous chloride tests. Not sure...

2009年12月12日 · After the shot is digested in aqua regia and filtered and rinsed we are left with a gray colored powdery precipitate. This precip we have been drying, mixing with borax and soda ash and smelting to yeild Ag usualy contaminated with anyware from 4% to 16% Au.