碱熔-长碘法测定含铬耐火砖粉中铜

Determination of Copper in Chromium-containing Refractory Brick Powder by Long Iodine Method with Alkali Fusion

含铬的耐火砖粉属于危险固废。准确检测耐火砖粉中的铜含量可以为耐火砖粉的后续分级处理提供依据。从碱熔-长碘法入手,一方面利用碱熔的方法溶解样品,确定了碱熔时间、碱熔温度及加过氧化钠的量,优化了碱熔步骤;另一方面,利用长碘法实现铬与铜分离,达到除铬的目的。用于测定铬干扰下的耐火砖粉中的铜,结果相对标准偏差(RSD,n=11)为0.58%~0.89%,对样品进行加标回收实验,加标回收率为98.9%~101%。利用碱熔-长碘法可以消除铬对铜测定的影响,能够满足日常测定需求。

Chromium-containing refractory brick powder belongs to hazardous solid waste.Accurate detection of copper content in refractory brick powder can provide a basis for the subsequent classification of refractory brick powder.This paper starts with the alkali fusion-long iodine method.On the one hand,the alkali fusion method is used to dissolve the sample,then the time and temperature for alkali fusion,and the amount of sodium peroxide added are determined,and the alkali fusion step is optimized.On the other hand,the method is used to separate chromium from copper,and achieve the purpose of chromium removal.This method is used for the determination of copper in refractory brick powder under the interference of chromium,with the relative standard deviation(RSD,n=11)of 0.58%-0.89%.The samples were spiked and recovered according to the experimental method,and the spiked recovery was 98.9%to 101%.The effect of chromium on the determination of copper can be eliminated by the alkaline fusion-long iodine method,which can meet the daily determination requirements.