Comparison of Catalysts Used to Determine CODcr of Severe Domestic Sewage

摘要

[Objective] The study aimed to find the best catalyst for the determination of CODCr of severe domestic sewage.[Method] Adopting potassium dichromate reflux method,respectively using MnSO4,Ag2SO4·MgSO4,CuSO4,KAl(SO4)2,CuSO4·KAl(SO4)2·(NH4)2MoO4 and Ag2SO4·Al2(SO4)3·MgSO4 as catalysts,we determined CODCr of severe domestic sewage,and compared their results with that of Ag2SO4.[Result] Used as catalysts in the determination of CODCr of severe domestic sewage,MnSO4,Ag2SO4·MgSO4,CuSO4,KAl(SO4)2,CuSO4·KAl(SO4)2·(NH4)2MoO4 and Ag2SO4·Al2(SO4)3·MgSO4 had good catalytic effects,especially Ag2SO4·Al2(SO4)3·MgSO4.Average CODCr of Ag2SO4·Al2(SO4)3·MgSO4 and Ag2SO4 was 229.32 and 254.28 mg/L separately,that is,the former accounted for 90.18% of the latter,so the result of Ag2SO4 could reflect the actual CODCr of severe domestic sewage better.[Conclusion] Ag2SO4 is the optimal catalyst for the determination of CODCr of severe domestic sewage.