碱熔-电感耦合等离子体原子发射光谱法测定铬铁矿中主次量元素

铬铁矿是一种极难分解的矿物,包含多种元素,常见的分析方法是将每种元素单独取样分析,费时费力,因此有必要寻求一种简便快速的分析方法。采用1.5g碳酸钠-四硼酸钠在1000℃熔融30min分解样品,选用50mL 25%(V/V)盐酸进行酸化处理,使用电感耦合等离子体原子发射光谱法(ICP-AES)测定铬、铁、铝、镁、硅、钙、钛、锰、钴、镍、钒等元素含量,建立了电感耦合等离子体原子发射光谱法测定铬铁矿中主次量元素铬、铁、铝、镁、硅、钙、钛、锰、钴、镍、钒等的方法。考察了铬对其他元素的影响,用加铬和不加铬的标准溶液系列测定其他元素,结果无明显差别,因此选用不加铬的标准溶液系列测定其他元素。在线性范围内,各元素校准曲线的线性相关系数均不小于0.9995;方法检出限为0.0003%~0.008%。按照实验方法测定铬铁矿标准物质GBW07201和GBW07819中铬、铁、铝、镁、硅、钙、钛、锰、钴、镍、钒,结果的相对标准偏差(RSD,n=12)为0.41%~5.5%,测定值和认定值一致。

Determination of major and minor elements in chromite ore by inductively coupled plasma atomic emission spectrometry after alkali fusion

Chromite ore is a kind of mineral which is extremely difficult to be decomposed. It contains a variety of elements, and the common analysis method is to analyze each element separately which was tedious and time-consuming. Therefore, it is necessary to seek a simple and rapid analysis method. The sample was decomposed with 1.5g of sodium carbonate-sodium tetraborate at 1000℃ for 30min. Then, the acidification treatment was conducted using 50mL of 25% (V/V) hydrochloric acid. The content of Cr, Fe, Al, Mg, Si, Ca, Ti, Mn, Co, Ni and V was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). The determination method of major and minor elements in chromite ores (including Cr, Fe, Al, Mg, Si, Ca, Ti, Mn, Co, Ni and V) by ICP-AES was established. The effect of chromium on other elements was investigated. Other elements were determined using standard solution series with and without chromium, and the results had no significant difference. Therefore, the standard solution series without chromium were used for the determination of other elements. The linear correlation coefficients of calibration curves of elements were all not less than 0.9995 within linear range. The detection limits of the method were between 0.0003% and 0.008%. The contents of Cr, Fe, Al, Mg, Si, Ca, Ti, Mn, Co, Ni and V in certified reference materials of chromite ore (GBW07201 and GBW07819) were determined according to the experimental method. The relative standard deviation (RSD, n=12) of results was 0.41%-5.5%. The determination results were consistent with the certified values.