室温条件下金属硫化物氧化产物及成因探讨——以河北高板河铅锌硫铁矿床为例

Exploration on the oxidation products and causes of metal sulphides under room temperature conditions—Case study of Gaobanhe lead-zinc-pyrite deposit in Hebei

在矿相学研究的基础上,运用X射线衍射、扫描电子显微镜等测试手段,对室温条件下高板河铅锌硫铁矿床金属硫化物矿石及其氧化产物进行了系统的矿物学研究。结果表明,原生矿物为黄铁矿、方铅矿、闪锌矿、方解石和白云石等,次生矿物主要为水铁矾、粒铁矾、四水白铁矾、李时珍石、黄钾铁矾、铅矾、水锌矾、石膏与无水石膏等,且矿石内、外层氧化后形成的次生矿物有所差异。高板河铅锌硫铁矿床金属硫化物氧化最终产物为相应铁矾类矿物,未形成氢氧化物,表明矿石是在较酸性环境中被氧化的。黄铁矿先氧化为含有低价态铁的四水白铁矾和水铁矾,随着氧化程度加深,逐渐形成含高价铁的粒铁矾。闪锌矿在富集高价铁和硫酸根离子的酸性环境下,易于形成李时珍石。方铅矿氧化产物为铅矾。研究结果揭示了室温条件下金属硫化物的氧化机制,同时为解决矿山环境污染问题提供了基础资料。

In this paper,based on the study of mineralogy,a systematic mineralogical study of metallic sulfide ores and their oxidation products from Gaobanhe lead-zinc-pyrite deposit in Hebei under room temperature conditions was carried out by using X-ray diffraction,scanning electron microscopy and other testing methods.The results show that the primary mineral assemblage is pyrite,galena,sphalerite,calcite and dolomite,etc.,and the secondary minerals are szomolnokite,roemerite,rozenite,lishizhenite,jarosite,anglesite,gunningite,gypsum and anhydrite,etc.,and the secondary mineral assemblages are different after the oxidation of the inner and outer layers of the ore.The final pro-ducts of Gaobanhe lead-zinc-pyrite deposit metal sulfide oxidation are corresponding iron vitriol minerals without forming hydroxides,indicating that the ore was oxidized in an acidic environment.Pyrite first oxidizes to rozenite and szomolnokite containing low-valent iron,and gradually forms roemerite with high-valent iron as the oxidation degree deepens.Sphalerite is easy to form lishizhenite in acidic environment enriched with high-valent iron and sulfate ion.Galena oxidation product is anglesite.The results reveal the oxidation mechanism of metal sulfide at room temperature and provide basic data for mine environmental pollution.