火焰原子吸收光谱法测定电镀废水中的铬

Determination of chromium in electroplating wastewater by flame atomic absorption spectrometry

采用碱性氢氧化锌溶液将电镀废水中的Cr(Ⅲ)沉淀分离后,再采用火焰原子吸收光谱仪测定水样中的Cr(VI)含量。另取水样经硝酸加热消解后测定总铬含量,再计算得到废水中Cr(Ⅲ)的含量。实验结果表明本方法的相对标准偏差为1.2%~3.9%,加标回收率为90.1%~105%,检出限为0.02 mg/L,能够满足控制标准要求。

The Cr(Ⅲ)in electroplating wastewater was precipitated with basic zinc hydroxide solution firstly,and then the Cr(VI)in the sample was determined by flame atomic absorption spectrometry.The total chromium content in the other sample digested by heating with nitric acid was determined,and then the Cr(Ⅲ)content could be calculated by substraction.The experimental results showed that the given method was compliant with the requirements of related discharge standard as shown by detection limit 0.02 mg/L,relative standard deviation 1.2%-3.9%,and spike recovery 90.1%-105%.