地沥青及油浸砂岩对U、Mo、Se、V、Re等的还原沉淀能力实验研究

Experimental research on the reduction and precipitation ability of land-bitumen and oil-soaked sandstone to U,Mo,Se,V and Re

笔者用实验地球化学方法,通过设定不同成矿元素与H2S反应的方程式,计算其反应的自由能,确定反应进行的方向和可能性,并利用“还原沉淀系数”定量判别不同岩石样品对成矿元素的还原强度。研究证实,石油的氧化物——地沥青及部分油浸砂岩对U、Mo、Se、V、Re等元素具有较强的还原沉淀能力,从而构成了砂岩型铀矿床成矿作用的重要环节。文章最后探讨了地沥青及油浸砂岩(主要还原剂为CH4)具有还原作用能力的热力学机理。

Based on the setted reaction equation of H2S with mineralization elements, this paper uses “ratio of reduction and precipitation” to quantitatively differentiate the rock intensity of reduction to mineralization elements by calculating the free energy to determine the reaction tendency and direction. It is founded that land bitumen, the oxides of petroleum and oil soaked sandstone are of high reduction and precipitation ability to U, Mo, Se, V and Re, and fairly important to uranium metallogeny. The reduction thermodynamics mechanism of the land-bitumen and oil-soaked sandstone （take CH4 as reductant） is also discussed.