Unexpected role of activated carbon in promoting transformation of secondary amines to N-nitrosamines.

摘要: Activated carbon (AC) is the most common solid phase extraction material used for analysis of nitrosamines in water. It also widely removal organics water treatment and as a catalyst or support some industrial applications. In this study, it was discovered that AC materials can catalyze transformation secondary amines to yield trace levels N-nitrosamines under ambient aerobic conditions. All 11 commercial ACs tested study formed from amines. Among different ACs, N-nitrosodimethylamine (NDMA) at pH 7.5 ranged 0.001% 0.01% initial amount aqueous dimethylamine (DMA) concentration, but 0.05-0.29% adsorbed DMA by AC. Nitrosamine increased with higher molecular weight amines, probably because adsorption Presence oxygen critical factor since dried air longer period time exhibited significantly nitrosamine yields. The AC-catalyzed formation observed surface wastewater effluent samples. Properties play an important role Preliminary evaluation indicated on reduced than oxidized surfaces. Overall, results show selecting reaction conditions are minimize analytical errors undesirable associated