X射线衍射和TIMA研究陕南镇巴地区富锂黏土岩的矿物组成及锂的赋存状态  

Mineralogical Composition and Occurrence State of Lithium in Lithium-Enriched Claystone in the Zhenba Area,Southern Shaanxi,by X-Ray Diffraction and TIMA Analysis

作　　者：周伟 张嘉升 祁晓鹏 徐磊 杨杰 ZHOU Wei;ZHANG Jiasheng;QI Xiaopeng;XU Lei;YANG Jie(Sino Shaanxi Nuclear Industry Group Geological Survey Co.Ltd.,Xi’an 710100,China)

机构地区：[1]中陕核工业集团地质调查院有限公司,陕西西安710100

出　　处：《岩矿测试》2024年第1期76-86,共11页Rock and Mineral Analysis

基　　金：陕西省地质勘查基金项目(61201908341);中陕核工业集团公司科技攻关项目(61210103)。

摘　　要：黏土岩型锂矿作为可利用锂资源的重要组成部分,由于其分布广、储量大而备受关注。陕西镇巴地区晚二叠世吴家坪组新发现黏土岩型锂矿(资源),Li_(2)O最高含量可达0.39%,达到了黏土锂矿的工业指标(0.2%),具有一定的开发利用价值。为了查明陕南镇巴地区富锂黏土岩中黏土矿物种类、含量及富锂黏土岩中锂的赋存状态,本文选取陕西镇巴地区富锂黏土岩,通过偏光显微镜鉴定初步查明黏土岩的矿物组成,利用X射线衍射(XRD)、全自动综合矿物分析系统(TIMA)分析技术定量查明富锂黏土岩中黏土矿物及主要元素含量。结果表明:该黏土岩主要由高岭石、铝绿泥石、伊利石、锂绿泥石等黏土矿物以及赤铁矿组成,含少量绿泥石、金红石等矿物。TIMA分析表明样品中锂绿泥石最高含量为8.94%,对应锂含量为0.12%(Li_(2)O含量为0.26%),略低于该样品全岩Li_(2)O含量(0.31%)。锂绿泥石呈丝缕状,不规则粒状,嵌布于一水软铝石、伊利石、铝绿泥石之间。综合研究认为镇巴地区富锂黏土岩中锂主要赋存于锂绿泥石中,其他矿物的锂含量很低。锂绿泥石、伊利石、高岭石等层状结构硅酸岩矿物具有很好的吸附性,锂以Li^(+)形式吸附于黏土矿物中。The newly discovered clay-type lithium ore(resources)in the upper Permian Wujiaping Formation in the Zhenba area of Shanxi Province has a maximum Li_(2)O content of 0.39%,which reaches the industrial index of clay lithium ore(0.2%),and has certain development and utilization values.To determine the mineral’s composition of lithium-enriched claystone and the occurrence state of lithium,a microscope was used to preliminarily observe the mineral composition,X-ray diffraction(XRD)and TIMA(TESCAN Integrated Mineral Analyzer)were used to analyze clay minerals and the main elemental content.The lithium-enriched claystone in the Zhenba area is mainly composed of kaolinite,sudoite,illite,cookeite and hematite,containing a small amount of chlorite,rutile and other minerals.TIMA analysis shows that the highest content of cookeite is 8.94%,and the highest Li content is 0.12%(Li_(2)O content is 0.26%),which is slightly lower than the whole rock Li_(2)O value(0.31%).The cookeite is silky and irregularly granular,and is dispersed between boehmite,illite and sudoite.The results show that lithium in claystone occurs mainly in cookeite,and other clay minerals have low lithium content.

关 键 词：TIMA分析技术 富锂黏土岩 锂的赋存状态 锂绿泥石 陕南镇巴地区 

分 类 号：P618.71[天文地球—矿床学] P619.23[天文地球—地质学]