絮凝沉淀-ICP-AES法测定废水中六价铬

Determination of hexavalent chromium in wastewater by ICP-AES after flocculent precipitation

建立了一种测定废水中六价铬的方法。该法以聚合氯化铝为絮凝剂,调节样品pH7.5~8.5范围,絮凝沉淀分离三价铬后取上清液消解,用ICP-AES测定六价铬。实验结果表明,该法标准曲线的相关系数达到0.999以上,检出限达到0.005mg·L^(-1),RSD为1.4%~3.2%,加标回收率93.0%~102%。该法不受样品浊度和色度影响,适用于废水中六价铬的测定。

This method used polyaluminum chloride as a flocculant,the pH value of the sample was adjusted to the range of 7.5-8.5.After flocculating and separating trivalent chromium,the supernatant solution was taken to digest,and the hexavalent chromium was determined by ICP-AES.Results showed that the correlation coefficient of the standard curve was above 0.999,the detection limit was 0.005mg·L^(-1),the RSD was 1.4%-3.2%,the recovery was 93.0%-102%.The method is not affected by the turbidity and chromaticity of samples,and is suitable for the determination of hexavalent chromium in wastewater.