自然铜不同炮制品矿相及化学成分的研究

Phase transformations and chemical compositions in different processing products of Pyritum Preparata

目的研究炮制对自然铜矿相及化学成分的影响。方法采用矿相显微镜、电子探针微区分析技术对自然铜不同炮制品的微结构、形貌、物相和化学成分进行分析。结果自然铜煅烧后成分发生了较大变化:其中黄铁矿(FeS2)变为磁黄铁矿(Fe1-xS),黄铜矿煅烧后Cu元素含量降低,而邻近的磁黄铁矿中Cu元素含量增加,Cu元素在磁黄铁矿中形成了固体溶液,提高了分散度;自然铜醋淬品中Pb、S等元素含量降低,在煅透的部位,Pb的含量不足生品的1/10。结论自然铜炮制前后矿相学的变化与其成分溶出存在一定的相关性。

Objective To study the phase transformations and chemical composition changes of Pyritum Preparata (PP) influenced by different processing. Methods To analyse the changes of microstructure, morphology, mineral phase, and chemical compositions in different PP by ore microscope, electron probe microanalyzer technique. Results Greater changes have taken place in chemical compositions of PP after calcination: pyrite (FeS_2) changed into pyrrhotite (Fe_(1-x)S), even changed into magnetite (Fe_3O_4); and chalcopyrite generated mutation to be low-copper chalcopyrite, the contents of Cu reduced, the rate of Cu/Fe changed. At the same time, in the pyrrhotite around the mutative chalcopyrite, the contents of Cu increased. That is to say, the Cu got into pyrrhotite and generated solid-solution with high dispersion, and then ore became loose and porous. In the hard-burned spot of calcined quenched samples by vinegar, the contents of Pb and S are far lower than non-burned spot, the minimum estimate of Pb is less than 1/10 of crude ore. Conclusion There is a co-relativity between phase transformations and dissolution of chemical compositions before and after calcining PP.