砷化氢发生砷锑钼蓝光度法测定饲料级硫酸锰中砷

Determination of arsenic in feed-grade manganese sulfate by hydrogen aresenide generation followed by arsenic antimony molybdenum blue spectrophotometry

介绍了砷化氢发生砷锑钼蓝光度法测定饲料级硫酸锰中砷的基本原理及操作方法,即:采用砷化氢发生法,用碘溶液氧化和吸收挥发出来的砷化氢(AsH3),被氧化吸收后的五价砷溶液,加入钼锑抗显色液后生成蓝色的砷锑钼蓝溶液,用光度法测定砷的含量。该方法适应HG 2936—1999饲料级硫酸锰含砷(As)质量分数≤0.000 5%质量指标的检测方法的准确度和精密度要求,可在硫酸锰生产企业中推广应用。

Basic principle and operation process of the determination of arsenic in feed-grade manganese sulfate by hydrogen arsenide generation followed by arsenic antimony molybdenum blue spectrophotometry were introduced. In operation process of the determination, first adopt hydrogen arsenide generation method to prepare arsine （ AsH3） ; then use iodine solution to oxidize and absorb volatilized arsine ; the quinquevalent arsenic solution was formed ; add antimony molybdenum anti-chromogenic agent to form arsenic antimony molybdenum blue solution ; finally the content of arsenic was determined by spectrophotometry. This method has met the accuracy and precision requirements of quality index testing method in Standard of Feed -grade Manganese Sulfate （mass fraction of As ≤0. 000 5 % ） HG 2936-1999, which can be popularized and applied in manganese sulfate manufacturing enterprises.