固体废物中氰化物全量的测定方法研究

建立了固体废物中氰化物全量的测定方法.选择金矿、电镀污泥等典型固废实际样品为研究对象,探讨了氰化物的全量测定结果与提取液pH的关系,确定使用pH值>12的氢氧化钠水溶液做为全量提取液.提取液中氰化物的含量采用硝酸银滴定法、异烟酸-吡唑啉酮或异烟酸-巴比妥酸分光光度法进行测定.方法检出限分别为0.24、0.03及0.02 mg/kg,实际固废样品加标回收率范围在92.2%~107%,6次测定结果的RSD为1.5%~11.7%.该方法检出限低、回收率高,精密度和准确度良好,适用于固体废物中氰化物的全量测定.

Determination of Total Cyanides in Solid Wastes

A method for determining the total amount of cyanides in solid wastes was established .Slag waste and electropla-ting sludge were used as actual samples, and experimental conditions such as the pH of extracting fluid were discussed.It had been verified that alkaline solution( pH>12) could be used as the best extraction fluid.Cyanides in extracting liquid could be measured by silver nitrate volumetric, nicotinic-pyrazolone and nicotinic-barbituric spectrophotometry methods.The detection limit is 0.24, 0.03 and 0.02 mg/kg, the recovery ranged from 92.2% to 107%, and the precision ranged from 1.5% to 11.7%.The method proved to be of high accuracy and good precision , and it was suitable for the determining of total amount of cyanides in solid wastes.