基于SO4^2-和BaCr溶液反应生成BaSO4沉淀,置换出定量的CrO4^2-,通过原子吸收法测定Cr,建立了间接测定萤石中硫的原子吸收光谱法。方法的工作曲线范围0.05~20μg/mL SO4^2-,检出限为0.017μg/mL S,适用于硫质量分数在0.01%~3%范围内萤石样品的测定。
An indirect AAS method for the determination of total sulfur in fluorite is described in this paper. The sulfur in the sample is transformed into sulfate to react with BaCrO4 forming chromate (CrO4^2- ). The chromate is displaced and the chromium is determined by AAS, and the sulfur content is calculated from the results of chromium determination. The calibration curve is quadratic over the concentration range of 0.05 - 20 μg/mL for sulfate. The RSD found is less than 7.4%. The proposed method is rapid, simple and active as compared with the conventional method.