常压微波消解分光光度法测定COD的研究

Study of spectrometric determination of COD by microwave atmospheric digestion

研究了常压微波消解分光光度法测定COD的方法,讨论了加热时间、硫酸银催化剂的用量、硫酸用量、硫酸磷酸的混酸体积比对微波消解法测定COD的影响。结果表明,微波加热60 s测定COD与国际标准测得COD基本一致,回收率达到96%;硫酸银用量对微波消解法影响不大,可实现无银催化,而硫酸用量不能减少;采用混酸代替硫酸后,V(硫酸)∶V(磷酸)=41∶时微波消解测定COD效果最佳。

The determination of COD by microwave atmospheric digestion is studied. The amount of Ag2SO4 catalyst, and mixed acid （H2SO4-H3PO4） ratio have an effect on the determination of COD by microwave atmospheric digestion. The result manifests that the determination value of COD heated in 60 s by microwave digestion coincides with the determination value of that heated in 2 h by international standard. The ratio of recovery is 96%.The amount of Ag2SO4 catalyst does not have much influence on the method of microwave digestion. It could be carried out catalyzing without Ag2SO4 catalyst. But the amount of H2SO4 couldn＇t be decreased. The ratio of mixed acid （H2SO4-H3PO4） is 4：1 has an optimum result about the determination of COD by microwave atmospheric digestion.