电感耦合等离子体原子发射光谱法测定重晶石选矿流程样品中硫酸钡

样品经稀盐酸低温溶解后过滤,以除去样品中的BaCO₃、BaCl₂、CaSO₄及其他易溶于HCl的杂质,采用Na₂CO₃高温熔融-热水浸取的方法处理沉淀及滤纸,然后再次过滤,用HNO₃-HClO₄溶解过滤后的沉淀物,选择Ba 233.527{144} nm作为分析线,在优化的仪器参数下以电感耦合等离子体原子发射光谱法(ICP-AES)测定样品溶液中Ba,从而间接测定了样品中BaSO₄的含量,据此,建立了Na₂CO₃熔融—ICP-AES测定重晶石选矿流程样品(原矿、尾矿、中矿和精矿)中BaSO₄的方法。结果表明,在波长为Ba 233.527{144} nm处,Ba未受到其他元素明显的光谱干扰;Ba的质量浓度在12~36 μg/mL范围内与其发射强度呈良好线性关系,校准曲线线性相关系数r=0.999 9;方法中Ba的检出限为0.14 μg/mL,换算为BaSO₄的检出限为0.24 μg/mL。按照实验方法测定重晶石选矿流程样品(原矿、尾矿、中矿和精矿)中BaSO₄,结果与重量法测定值相吻合,相对标准偏差(n=6)为0.39%~4.1%。

Determination of barium sulfate in beneficiation process sample of barite by inductively coupled plasma atomic emission spectrometry

The sample was dissolved at low temperature by diluted hydrochloric acid and filtrated for eliminating the impurities such as BaCO₃, BaCl₂, CaSO₄ and other substances which were dissolved easily in HCl. The precipitate and filter paper was melted at high temperature with Na₂CO₃ followed by hot water leaching. The filtration was conducted again, and the precipitate was then dissolved with HNO₃-HClO₄. Then the content of Ba in sample solution was determined by inductively coupled plasma atomic emission spectrometry(ICP-AES) under optimal instrumental parameters with Ba 233.527{144} nm as analytical line. Thus, the content of BaSO₄ in sample was indirectly calculated. Based on this, a determination method of barium sulfate in beneficiation process sample of barite (raw ore, tailing, middling and concentrate) was established by ICP-AES after Na₂CO₃ fusion. The results indicated that there was no obvious spectral interference by other elements at wavelength of Ba 233.527{144} nm. The mass concentration of Ba in range of 12-36 μg/mL showed good linearity to the corresponding emission intensity. The linear correlation coefficient of calibration curve was r=0.999 9. The detection limit of method for Ba was 0.14 μg/mL, which was equivalent to 0.24 μg/mL for BaSO₄. The content of BaSO₄ in the actual samples of raw ore, tailing, middling and concentrate in beneficiation process of barite was determined according to the experimental method. The results were consistent with those obtained by gravimetric method. The relative standard deviations (RSD, n=6) were between 0.39% and 4.1%.