微波消解法快速测定工业污水中的化学需氧量

Rapid determination of COD in industrial wastewater by microwave digestion method

采用微波消解法测定了工业污水中化学需氧量(COD)质量浓度,并与重铬酸钾回流法测定结果进行了对比。结果表明,最佳消解条件为:H2SO4-Ag2SO4混合溶液(前者用量为500 m L,后者用量为5 g)用量10 m L,消解时间10 min,水样5 m L,氧化剂重铬酸钾用量5.0 m L。采用微波消解法,分别对COD质量浓度为30,100,500,1 000 mg/L的标准溶液进行了测定,COD质量浓度平均实测值依次为30,101,495,994 mg/L,变异系数依次为3.33%,1.14%,1.34%,1.12%。分别采用微波消解法与标准回流法对工业污水COD质量浓度进行了测定,二者结果基本一致,相对误差均低于±4.00%。

The mass concentration of chemical oxygen demand （COD） in industrial wastewater was determined by microwave digestion method, and compared with the results by potassium dichromate method. The results showed that the optimum digestion conditions were as follows： H2SO4 - Ag2SO4 mixed solution 10 mL（ HzSO4 500 mL,Ag2SO45 g） , od, the mass concentration of 30, 100, 500, 1 000 mg/L of the standard solution was determined, and their average measurement values were 30, 101,495, 994 mg/L, coefficients of variation 3.33% , 1.14% , 1.34% , 1.12% respectively. The mass concentrations of COD in industrial wastewaters were determined by microwave digestion method and standard reflux method, both results were basically identical, and relative errors were less than ± 4.00%.