The scrapped graphite crucible is crushed,mixed,fractionated and ground to obtain a sample that meets the testing requirements.Weigh a certain amount of sample,adjust the silica acidity of the material by batching,and add a certain amount of potassium nitrate to eliminate the excessive reducing force in the sample.The material is melted at high temperature in the crucible to obtain a lead buckle containing precious metals,and the obtained lead buckle is ash blown in an oxygen-rich state,and the lead and base metals are oxidized and separated from precious metals such as gold and silver to obtain gold and silver alloy particles containing precious metals.Gold flakes are obtained by nitric acid separation,and the gold content in the sample is calculated by gravimetric method.
Graphite crucible slag sampleHigh temperature meltingAsh blowingNitric acid dissolves silverCalculate the gold content