气相—微波—热压法分解高纯金的研究

Study on Dissolution of Gold by the Method of Vapor Phase-Microwave Heating under Pressure

This paper reports the dissolution of gold by the method of vapor phase-microwave heating under pressure High purity gold was weighed out and placed into a small quartz dish. In a PTFE high pressure vessel a triangle support, on which the small quartz dish was placed, was mounted. The cover of the vessel was screwed fast after adding concentrated HCl-fuming HNO_3(14:1). The vessel was put in the microwave oven and heated with 200W microwave power instantly to make the gold dissolved by the ascending acid vapor. The analysis by ICP-AES of 26 impurity elements,such as Pt,Pd,Fe,Ni,Ca,Al,Pb,Bi, Cu,Sb etc. contained in the dissolved product has shown that the latter has not been contaminated by the impurities in the mixed acids. This method has the advantages of instantaneous heating, quick decomposition, energy saving, no loss of volatile components and no contamination, it can be used to prepare samples in high purity gold analysis or to prepare uncontaninated gold compounds.