难处理金矿浸出预处理过程的FeS_2-FeAsS-H_2O系电位-pH图  

E-pH diagram of FeS_2-FeAsS-H_2O system for leaching pretreatment of refractory gold ore

作　　者：金创石[1,2] 张廷安[1] 牟望重[1] 曾勇[1] 刘燕[1] 吕国志[1] 蒋孝丽[1] 

机构地区：[1]东北大学多金属共生矿生态化利用教育部重点实验室,沈阳110819 [2]金策工业综合大学物理化学教研室,朝鲜平壤999093

出　　处：《材料与冶金学报》2011年第2期120-124,共5页Journal of Materials and Metallurgy

基　　金：国家"十一五"科技支撑计划项目(2008BAB34B01);国家自然科学基金资助项目(51004033;50974035;51074047)

摘　　要：难处理金矿中,金为微细浸染型嵌布在黄铁矿和毒砂的晶格中而不能被充分浸出.本文通过热力学计算绘制了298.15KFeS2-FeAsS-H2O系的电位-pH图,由图可知黄铁矿和毒砂均可以被O2等氧化剂分解.FeAsS的稳定区完全包含在FeS2的稳定区范围内,说明在酸性条件下毒砂比黄铁矿的稳定性差,更容易被分解.当电位及酸度较高时,黄铁矿及毒砂中的硫以稳定的HSO4-、SO42-形式存在,而砷以H3AsO4的形式存在,表明预处理过程能够将包裹在金表面的硫化矿物解离脱除.热力学计算的结果为难处理金矿的浸出预处理过程提供了理论依据.Minutely dipped gold grains were wrapped up by arsenopyrite and pyrite in the refractory gold ore.In this paper,E-pH diagram of FeS2-FeAsS-H2O system was drawn according to thermodynamic calculation.Pyrite and arsenopyrite could be decomposed by O2 and other oxidants.The stable region of FeAsS is completely contained in that of FeS2,which illustrates that arsenopyrite is more easily to be decomposed than pyrite at the acidic condition.When the deposit and acid concentration are high,sulfur of pyrite and arsenopyrite could exist as stable style of HSO-4 and SO2-4,and arsenic could exist as H3AsO4.The existence of stable regions demonstrate that sulfide ores packing the surface of gold could be desorption.Thermodynamic results provide theoretical principle for leaching pretreatment of refractory gold ore.

关 键 词：难处理金矿 预处理 电位-PH图 黄铁矿 毒砂 FeS2-FeAsS-H2O系 

分 类 号：TF803.21[冶金工程—有色金属冶金]