AWWA WQTC57071

Bromamines (NH2Br, NHBr2, NBr3) play an important role in drinking water disinfection and disinfection byproduct (DBP) formation, both of which are affected by bromamine kinetics. The decomposition of bromamines was been investigated in this study for the pH range of 6.6 to 9.4 using a stopped-flow system. The paper presents a kinetic model describing the conversion between NH2Br and NHBr2, and subsequent decomposition reactions is proposed to describe the relatively rapid disappearance of total bromamines as well as the concentration profiles of each species when the N/Br ratio is above 1. The disproportionation reaction is a general acid catalyzed reaction, affected by solution pH and buffer compounds. At relatively high solution pH, when NH2Br is the dominant species, bromamines mainly decompose through the 3rd reaction given above. However, at relatively low solution pH, when NHBr2 is predominant, the 2nd reaction occurs more rapidly. The proposed model provides a mechanistic approach to evaluate bromamine decomposition. Includes 10 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

11/01/2002

Number of Pages:

6

File Size:

1 file , 370 KB