The nature of micro- and nanocrystalline weathering products of sulfidic ores rich in As and Sb

富As、Sb硫化矿微晶和纳米晶风化产物的性质

• 批准号: 265185880
• 负责人: Professor Dr. Juraj Majzlan, Ph.D.
• 金额: --
• 依托单位: Lehrstuhl Allgemeine und Angewandte Mineralogie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/265185880?language=en
• 关键词: nature; micro; nanocrystalline; weathering; products

Sulfidic ores rich in arsenic (As) and antimony (Sb) are commonly exploited and serve as a source of many important metals, metalloids, and raw materials. Mining waste, either historical, recent, or currently produced, represents a major environmental load, even though the mining and processing technologies are steadily improving. Upon contact with atmosphere and hydrosphere, the sulfidic ores and the associated mining wastes weather, transform, and may pollute the environment. Here I propose to study crystal structures and crystal chemistry of selected weathering products of ores rich in As and Sb. They are common and often control the mobility and bioavailability of the toxic metalloids and metals. Yet, their nature is not known. Within this proposal, we will target phases from the systems Fe(III)-As(V)-S(VI)-H2O and (Cu,Zn,Ag,Bi,Fe)-Sb(V)-As(V)-H2O. Namely, we will study the ferric arsenates kankite, zykaite, and a suite of previously unknown phases from Rotgülden (Austria). From the latter system, we will inspect weathering products of tetrahedrite-tennantite ores. In addition to detailed optical microscopy and electron microprobe work, the focus of the work is in the diffraction techniques: high-resolution powder X-ray diffraction and electron precession diffraction. The latter method, in particular, will be used to decipher the crystal structure of the nanosized mixtures of weathering products. This project will be a benchmark study of nanosized natural weathering products. Although transmission electron microscopy has been used commonly in environmental studies, the possibility to solve crystal structures of all phases in a complex nanomixture is truly a revolution. It will open the door to an exhaustive and complete characterization of the weathering products and their transformation sequences.

富含砷 (As) 和锑 (Sb) 的硫化矿石被广泛开采，是许多重要金属、准金属和原材料的来源。尽管采矿和加工技术正在稳步改进，但无论是历史上的、最近的还是目前产生的采矿废物都是主要的环境负荷。当与大气和水圈接触时，硫化矿石和相关采矿废物会发生变化，并可能污染环境。在这里，我建议研究富含砷和锑的矿石的选定风化产物的晶体结构和晶体化学。它们很常见，通常控制有毒类金属和金属的流动性和生物利用度。然而，它们的性质尚不清楚。在本提案中，我们将针对 Fe(III)-As(V)-S(VI)-H2O 和 (Cu,Zn,Ag,Bi,Fe)-Sb(V)-As(V)-H2O 体系中的相。也就是说，我们将研究来自 Rotgülden（奥地利）的砷酸铁 kankite、zykaite 以及一系列以前未知的相。从后一个系统中，我们将检查四面体-铁锰矿矿石的风化产物。除了详细的光学显微镜和电子微探针工作外，工作的重点是衍射技术：高分辨率粉末 X 射线衍射和电子进动衍射。特别是后一种方法将用于破译纳米级风化产物混合物的晶体结构。该项目将成为纳米级自然风化产品的基准研究。尽管透射电子显微镜已广泛用于环境研究，但解决复杂纳米混合物中所有相晶体结构的可能性确实是一场革命。它将为对风化产物及其转变序列进行详尽而完整的表征打开大门。