分析化学实验室含银废弃物的处理及循环利用

Treatment and Recycling of Silver-containing Waste in Analytical Chemistry Laboratory

介绍了用铁还原置换法处理分析化学实验室含银废弃物的操作过程及注意事项。首先将含银废弃物均转化为氯化银固体;然后将氯化银在热浓盐酸中与铁片反应得到粗制银粉,粗制银粉再与1∶1硝酸反应转化成硝酸银溶液;最后用莫尔法和重铬酸钾法分别测定硝酸银溶液和副产品氯化铁溶液浓度。本方法中氯化银转化为硝酸银的转化率为55.77%。硝酸银溶液和氯化铁溶液均可用于分析化学实验教学,从而实现了含银废弃物的循环利用。

The operation and precautions of the treatment and recycling of silver-containing waste in analytical chemistry laboratory by iron reduction replacement was introduced.First,silver-containing waste was translated into silver chloride.Then,crude silver powder was produced by silver chloride reacting with iron in hot concentrated hydrochloric acid and subsequently translated into silver nitrate solution in hot 1∶1 nitric acid.Last,concentrations of silver nitrate solution and the by-product ferric chloride solution were determined by Mohr's and K 2Cr 2O 7 methods,separately.By this method,the conversion rate of silver chloride to silver nitrate was 55.77%.Silver nitrate and ferric chloride solutions could be reused in analytical chemistry experiments.Thus,the recycling of silver-containing wastes was realized.