花岗斑岩类岩石中Au、Pd溶解性状的实验研究

Experimental research on dissolution properties of Au and Pd contained in granite-porphyry

研究花岗斑岩类岩石中Au、Pd的溶解性状 ,对于研究其溶解、迁移、沉淀条件有着重要的理论价值。研究结果表明 ,花岗斑岩中Au、Pd地球化学性状明显不同 ,Au活性显著 ,Pd惰性特征明显。在T =2 5 0℃、P =2 0× 10 5～ 30× 10 5Pa、pH =7.5 6的条件下 ,Au浸出率最低 ,易于沉淀成矿 ;在T =10 0℃、P =10 0× 10 5Pa、pH =8.2时 ,Au浸出率高 ,最易被活化溶解 ;当T =5 0 0℃ ,P =5 0 0× 10 5Pa ,pH =8.5时 ,Au浸出率中等 ,易被搬运、迁移。Pd易于沉淀成矿的条件是T =10 0℃ ,P =5 0 0× 10 5Pa ,pH =8.2 ;Pd易于活化溶解的条件是T =2 5 0℃ ,P =10× 10 5Pa ,pH =8.5 ;在T =30 0℃、P =(2 0～ 30 )× 10 5Pa、pH =6条件下发生搬运迁移。

The research on dissolution properties of Au and Pd contained in granite-porphyry is of great significance for the study of conditions under which Au and Pd dissolve, migrate and deposit.The result indicates that geochemical properties of Au and Pd contained in granite-porphyry are notably different-the activity of Au is obvious, whereas the inertia of Pd is obvious.The leaching rate of Au is lest and the gold is easy to deposit and mineralize when the temperature is 250 degree centigrade, the pressure is 20×10 5～30×10 5Pa, and the pH value is 7.56; the rate is highest and the gold is easy to be activated and dissolved when the temperature is 100 degree centigrade, the pressure is 100×10 5Pa, and the pH value is 8.2 ; the rate is medium and the gold is easy to migrate.As to Pd, the conditions for deposition and mineralization are 100℃, 500×10 5Pa and 8.2, for activation and dissolution are 250℃,100×10 5Pa,and 8.5, and for migration are 300℃,(20～30)×10 5Pa and 6.