锰矿石中硅含量测定的氟硅酸钾容量法确认  

A Determination of Silicon Content in Manganese Ore by Potassium Fluosilicate Volumetric Method

作　　者：李蕾 龙希建 LI Lei;LONG Xijian(Team 409, Hunan Bureau of Geology and mineral exploration and development, Yongzhou, Hunan 425000, China)

机构地区：[1]湖南省地质矿产勘查开发局四〇九队,湖南永州425000

出　　处：《中国锰业》2022年第2期85-89,共5页China Manganese Industry

摘　　要：锰矿中硅含量的高低是评价锰矿质量指标的主要参数之一,其测定方法的科学性、准确性和可靠性是关系锰矿利用评价的重要依据。采用碱熔融分解试样,热水提取使硅形成可溶性硅酸溶于水中,再在强酸性介质中于氯化钾饱和下加入过量的氟化钾,使硅形成氟硅酸钾沉淀与其他矿物组分元素分离,将分离所得氟硅酸钾沉淀加入沸水中使之水解析出等摩尔量的氢氟酸,再用氢氧化钠标准溶液滴定,经换算测得二氧化硅含量。结果表明:方法加标回收率98.71%~101.28%,相对标准偏差0.49%~0.91%,相对误差0.24%~2.04%,满足《地质矿产实验室测试质量管理规范第3部分:岩石矿物样品化学成分分析》要求。Silicon content in manganese ore is one of the important parameters to evaluate the quality index of manganese ore.The scientificity,accuracy and reliability of its determination method are the main basis for the utilization evaluation of manganese ore.In this paper,the sample is decomposed by alkali melting and it is extracted by hot water to make the silicon form soluble silicic acid and dissolve in water.Then in the acidic medium,an appropriate excess of potassium fluoride is added under the saturation of potassium chloride to make the silicon form potassium fluorosilicate precipitation and separate it from other mineral components.The separated potassium fluorosilicate precipitation is added to boiling water to make the water resolve hydrofluoric acid of equal molar amount.We titrate it with sodium hydroxide standard solution and measure the silica content after conversion.In confirmation of the method,the recovery of the method is 98.71%~101.28%,the relative standard deviation is 0.49%~0.91%,and the relative error of the method is 0.24%~2.04%,which meets the requirements of quality management specification for testing in geological and mineral laboratories.In the thesis of Part 3,we put forward the chemical composition analysis of rock and mineral samples.

关 键 词：锰矿石 硅含量 碱熔融分解 氟硅酸钾 容量法 

分 类 号：O653[理学—分析化学] P575[理学—化学]