黄铁矿表面氧化机理及动力学影响因素研究进展

A Brief Overview on the Mechanism and Kinetic Influencing Factors of the Pyrite Surface Oxidation

黄铁矿作为矿区环境中最为常见的金属硫化物尾矿,在表生环境下易被氧化形成酸性矿山废水(acid mine drainage,AMD),进而产生一系列环境污染问题。因此,黄铁矿表面氧化机理及其动力学影响因素研究一直是矿区污染环境治理领域的研究热点。首先概述了黄铁矿基本结构和物理化学性质,指出黄铁矿表面氧化机理及其规律研究对于从源头上减缓酸性矿山废水(acid mine drainage,AMD)的产生、改善黄铁矿光伏材料的应用缺陷、从黄铁矿结构中高效浸出伴生的贵重金属及完善地球上Fe、S循环都具有重要意义。然后,较为系统地从黄铁矿氧化形成AMD机理、微生物介导下的黄铁矿生物氧化机理、黄铁矿表面氧化机理电化学研究、黄铁矿表面氧化过程中硫元素转化机理等4个方面综述了黄铁矿表面氧化机理。紧接着,分别概括了腐殖酸、无机酸根离子、常见氧化剂对黄铁矿化学、生物及表面电化学氧化对黄铁矿表面氧化动力学的影响。最后,指出未来可借助一些原位微观界面研究手段,进一步加强微生物与黄铁矿的界面作用的微观机理研究,探究多因素耦合作用下黄铁矿表面氧化规律,建立一个预测自然环境下多因素耦合下黄铁矿氧化速率模型。

Pyrite,as the most common metal sulfide tailings in the mining environment,is easily oxidized to form acid mine wastewater(AMD)in the supergenetic environment,which leads to a series of environmental pollution problems.Therefore,the study of pyrite surface oxidation mechanism and its kinetic influencing factors have always been a research hotspot in the field of environmental pollution control in mining areas.First of all,this paper summarizes the basic structure and physical and chemical properties of pyrite,points out that the pyrite surface oxidation mechanism and regularity study have important significance for reducing the acid mine drainage production in the first place,perfecting the defect in the application of pyrite photovoltaic material,effectively leaching associated precious metal from pyrite structure and improving the earth sulfur cycle.Then,the surface oxidation mechanism of pyrite was systematically reviewed from four aspects:the mechanism of forming AMD by pyrite oxidation,the biological oxidation mechanism of pyrite mediated by microorganisms,the electrochemical study of the surface oxidation mechanism of pyrite,and the transformation mechanism of sulfur elements in the surface oxidation process of pyrite.And then,the effects of humic acid,inorganic acid ions and common oxidants on pyrite chemistry,biology and surface electrochemical oxidation on pyrite surface oxidation kinetics were summarized respectively.Finally,it is pointed out that some in situ microscopic interface research methods could be used in the future to further strengthen the microscopic mechanism of the interaction between microorganisms and pyrite,explore the oxidation law of pyrite surface under multi-factor coupling action,and establish a model to predict the oxidation rate of pyrite under multi-factor coupling in natural environment.