标准回流法和微波消解法测定高氯水样化学需氧量的对比

Study on Contrast of Chemical Oxygen Demand in Assay of High Chlorine Water Sample with Methods of Standard Reflux and Microwave Digestion

[目的]实现高氯水样中化学需氧量的快速、准确测定。[方法]分别用标准回流法和微波消解法测定高氯水样中化学需氧量的含量,比较2种方法的测定结果。[结果]当国标COD理论值为(102±4)、(125±4)、(138±4)mg/L时,标准回流法测定的高氯水样中化学需氧量的含量分别为100.0、125.2、136.4 mg/L,微波消解法测定的高氯水样中化学需氧量的含量分别为103.6、126.8、139.0 mg/L,2种方法测定的COD理论值无显著差异(P>0.05),精密度基本相同。[结论]与标准回流法相比,微波消解法测定高氯废水中化学需氧量具有时间短、操作简便、费用低等优点,且精密度无显著性差异(P>0.05)。

[ Objective] The aim was to realize fast and accurate assay of chemical oxygen demand in high chlorine （C]） water sample. [ Method ] The methods of standard reflux and microwave digestion were adopted respectively to assay the content of chemical oxygen demand in high Cl-water sample, and the measured results of two methods were compared, [Result] When the COD theoretical values of International Standard were （ 102 ± 4）, （ 12.5 ±4） and （ 138 ± 4）mg/L, the content of chemical oxygen demand in high Cl-water sample assayed with the standard reflux method were 100.0, 12,5.2 and 136.4 mg/L resp. ; the content of chemical oxygen demand assayed with microwave digestion methods were 103.6, 126,8 and 139.0 mg/L resp, COD theoretical values assayed with 2 methods （ P 〉 0.05） had no evident difference and were basically identical in precision. [ Conclusion] In assaying chemical oxygen demand in high chlorine waste water, compared with standard reflux method, the microwave digestion method had advantages of short time, easy operation and low cost, and no significant discrepancy in precision （ P 〉 0.05）.