新疆尉犁蛭石矿中金云母/蛭石混层结构研究

Structural Research on Phlogopite/vermiculite Interlayered Mineral from Xinjiang Weili

蛭石矿中常伴生有金/黑云母结构,云母层的存在严重影响了蛭石矿的性能,现有方法不能充分揭示混层的晶体结构特征和蛭石晶层及金云母晶层含量。本文以新疆尉犁蛭石矿为研究对象,利用X-射线衍射(XRD)和X射线荧光光谱(XRF)研究尉犁蛭石结构和相含量。以XRD强度理论和分子量为基础,建立新型水金云母(金云母-蛭石的1∶1规则间层矿物)的参比强度近似计算方法,研究水金云母分子量变化对于定量相分析结果的影响,并与已有的分晶层方法计算得到的各晶层含量进行系统比较。结果表明新疆尉犁蛭石由24.56%的蛭石和75.44%的水金云母组成;以参比强度为基础的XRD定量分析方法具有结果可靠、分析简单,同时可以获得层状硅酸盐多层次结构信息的优点。

Vermiculite is often interlayered with phlogopite or biotite which seriously influences the performance of the minerals. The characteristic of intedayed crystal structure and phase contents can not be fully obtained by the present methods. In present study, sttructure and phase contents of the vermiculite from Xinjinag Weili were investigated by X-ray diff action（XRD） and X-ray fluorescence（CRF） analysis. Based on XRD intensity theory and molecular weight, a new approximate method to calculate reference intensity ratio （RIR） of hydro-phlogopite was proposed. The error caused by variation of molecular weight was discussed in detail and the obtained phase contents were compared with individual crystal layer method. The results showed that Xinjiang Weili vermiculite was composed of 24.56% vermiculite and 75.44% hydro-phlogopite ; quantitive phase analysis method based on RIR was stable, reliable and simple, and could get more structural information of lamellar silicate.