重铬酸钾法测定废水COD条件改进的研究

The Study on Improving Condition Surveying COD in Wastewater with K_2Cr_2O_4

本文提出用CuSO_4为催化剂,在H_2SO_4～H_3PO_4混酸溶液中重铬酸钾回流测定废水COD的方法。条件实验表明,最佳测定条件为:CuSO_4浓度为7.0×10^(-2)mol·l^(-1)(混酸溶液);H_2SO_4:H_2PO_4=5:1(体积比);回流时间2小时。通过对实际废水的测定,与标准方法对比,结果满意。本方法的优点是不用贵重试剂Ag_2SO_4,改用CuSO_4作催化剂,精密度,准确度较高。

The method surveying COD in wastewater was reported in which CuSO_4 as a Catalyst in mixture of H_2SO_4 and H_3PO_4. The result of experiment showed that optimun condition were C CuSO_4=7.0×0^(-2)ml·l^(-1) H_2SO_4: H_3PO_4=5:1 (volume); reactive time was two hours. It was Successed in precision. The Strong point of method was that CuSO_4 was instead of Ag_SO_4, and had a practical valve.