江西广丰黑滑石的矿物学特征及其材料学意义

As a unique type of clay minerals, black talc is a characteristic non-metallic mineral resource in China. In the past decades, deposits of black talc have been widely discovered and evaluated in South and Southwest China. Although talc has been applied in a wide range of areas, the application and exploration of black talc is still limited due to the dark color. This project aims to study the black talc in Guangfeng talc deposit, Jiangxi Province, which has been proven to be the largest black-talc deposit in the world. Based on the systematic geological survey, multiple mineralogical techniques, geochemical measurements and material characterization methods will be employed to disclose the crystal chemistry of the black talc. The properties and occurrence of carbon in black talc will be focused on, and then the mechanism for darkening will be explored in the view of crystallochemistry. Through systematic analysis of the geological background, mineral assemblage and geochemistry of black talc ores, the genesis of black talc and related geological conditions will be discussed. On the basis of mineralogical study, the surface chemistry and physical-chemical properties of black talc will be studied by means of surface analysis and molecular simulatios in order to evaluate the material properties. By comparing with ordinary talc, the special material properties of black talc will be further explored and proposed. This study will provide theoretical basis for the development and application of the massive black talc ores which widely distribute in China.

黑滑石是一种独特的粘土矿物类型，也是我国的特色非金属矿产类型，在华南和西南地区广泛分布。尽管滑石业已应用于广泛的领域，但黑滑石因颜色所限，其开发应用程度仍然很低。本项目拟以探明储量居世界首位的江西广丰震旦系黑滑石矿为研究对象，在系统地质调查的基础上，综合运用多种矿物学、地球化学和材料学分析测试手段，精细研究黑滑石的晶体化学特征，重点查明黑滑石中碳的赋存形式，揭示其致黑机制。在系统分析黑滑石矿产出的地质背景、矿石矿物组成和地球化学特征的基础上，探讨黑滑石的形成机理和地质条件。在此基础上，将利用表面分析手段和分子模拟方法，研究黑滑石的表面化学特征和矿物物理性质，对比普通滑石的材料学属性，进一步探讨黑滑石独有的材料应用价值。本研究成果将对我国广泛分布的巨量黑滑石资源的开发和应用提供理论支撑。

本项目以江西广丰震旦系黑滑石矿为研究对象，在系统地质调查的基础上，综合运用多种矿物学、地球化学和材料学分析测试手段，精细研究黑滑石的晶体化学特征；通过对黑滑石中有机碳的特征和赋存状态的表征，发现黑滑石中有机质类似石墨烯，主要位于滑石层间区域，在滑石颗粒间孔隙中也有一定的分布，这一发现从晶体化学的角度阐明了黑滑石的致色机制。通过对黑色滑石矿的地质背景、矿物组合和地球化学的系统分析，提出了黑色滑石矿的沉积成因机制，在浅海或泻湖极端富镁Mg、Si环境中，形成层厚1~2个单元层的镁硅酸盐四面体-八面体-四面体(T-O-T)，并与水体中微生物成因有机质共沉淀。此外，我们还开展了黑滑石的吸附实验，发现黑滑石的比表面积、吸附能力远高于普通的白滑石，具有作为吸附材料的潜力。本研究将为我国广泛分布的黑滑石矿的开发和应用提供理论依据。