Silicon-molybdenum blue spectrophotometric determination of silica in fluorite and its concentrate.
YANG Chao-shuai, ZHOU Jian-hui, KONG Xing-hua,et al
(1.Tangshan Laboratory,Hebei Geology and Mineral Exploration Bureau, Tangshan 063000,China;
2.Laboratory of Tangshan Iron and Steel Group ironworks, Tangshan 063000, China)
Abstract：The paper proposed an improved way of silicon-molybdenum blue spectrophotometric method which has been used in the determination of silica content within different ranges in fluorite and concentrate. Using sodium hydroxide as flux, the sample was melted in silver crucibles instead of expensive platinum crucible. The sample solution preparation process was optimized by using back-acidification method to improve the stability of the sample solution. Using aluminium trichloride to replace boric acid which has buffer effect to remove the interference of excessive fluorine with the solution, and the introduction of the silica in glassware was avoided during the whole operation. The way of acidification for the standard solution was changed. The calibration curve was linear in the range of 50-1 000 μg, r≥0.999 7. By analyzing and comparing the five fluorite standard samples with different content of SiO2, the results of this method were consistent with the certified values of the standard samples and the found values of HF evaporation gravimetric method. All of the relative standard deviations were less than 0.5 %. Through verification by the “ t-Test ”, there was no significant difference between the results of this method and the certified values of the standard samples. This improved method has simple chromogenic system. It can be used for analyzing fluorite containing no more than 62.00 % SiO2.
杨朝帅，周建辉，孔幸花 ，孙 静 . 硅钼蓝光度法测定萤石及其精矿中二氧化硅的含量[J]. 冶金分析, 2012, 32(7): 59-62.
YANG Chao-shuai, ZHOU Jian-hui, KONG Xing-hua,et al. Silicon-molybdenum blue spectrophotometric determination of silica in fluorite and its concentrate.. , 2012, 32(7): 59-62.
