University of Surrey

Test tubes in the lab Research in the ATI Dance Research

Contribution of amide-based coagulant polyacrylamide as precursors of haloacetamides and other disinfection by-products

Ding, Shunke, Chu, Wenhai, Bond, Tom, Cao, Zhongqi, Xu, Bin and Gao, Naiyun (2018) Contribution of amide-based coagulant polyacrylamide as precursors of haloacetamides and other disinfection by-products Chemical Engineering Journal, 350. pp. 356-363.

[img]
Preview
Text
Accepted Manuscript 5-6-18.pdf - Accepted version Manuscript

Download (1MB) | Preview

Abstract

Coagulation is a widespread method of drinking water treatment. Coagulation can mitigate the formation of disinfection by-products (DBPs) through removing their precursors. Here we report that the amide-based organic polymer coagulants polyacrylamide (PAM) and its monomer acrylamide (AM) can serve as a source of HAcAm and other DBPs including trihalomethanes (THMs) and haloacetonitriles (HANs) during chlor(am)ination. The impact of the key experimental parameters, including reaction time, Cl2 or NH2Cl dose, pH and initial bromide concentration on the formation of DBPs was investigated. Furthermore, the major reaction pathways for AM transformation and DBP formation during chlor(am)ination are proposed and include N-chlorination, addition, and substitution. Jar tests demonstrated that coagulation by alum coupled with PAM achieved greatest removal of DOC and UV254, compared with alum and PAM alone. Treatment with PAM didn’t significantly promote the formation of THMs and HANs during post-chlorination, indicating that the PAM residual hardly contributes to THM and HAN formation. However, coagulation by applying alum salt and PAM increased total HAcAm concentrations by 2.2–3.1 μg/L at the higher PAM dose (2.0 mg/L), compared with alum alone. Therefore, the contribution of PAM to the formation of HAcAm cannot be ignored. The results highlight that the generation of secondary pollutants from the amide-based engineered organic polymer coagulants in drinking water should be considered; that is, they can adversely affect water quality because of their ability to enhance DBPs generated during downstream disinfection. Accordingly, the understanding of the stability and reactivity of PAM in the presence of disinfectants could help to better evaluate their contribution to the formation of HAcAms, THMs, and HANs, which has important implications for their environmental fate, transport, and responsible applications.

Item Type: Article
Divisions : Faculty of Engineering and Physical Sciences > Civil and Environmental Engineering
Authors :
NameEmailORCID
Ding, Shunke
Chu, Wenhai
Bond, Tomt.bond@surrey.ac.uk
Cao, Zhongqi
Xu, Bin
Gao, Naiyun
Date : 2 June 2018
DOI : 10.1016/j.cej.2018.06.002
Copyright Disclaimer : © 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/
Uncontrolled Keywords : Polyacrylamide; Coagulant; Haloacetamide; Disinfection by-products; Drinking water
Depositing User : Clive Harris
Date Deposited : 07 Jun 2018 14:53
Last Modified : 03 Jun 2019 02:08
URI: http://epubs.surrey.ac.uk/id/eprint/847018

Actions (login required)

View Item View Item

Downloads

Downloads per month over past year


Information about this web site

© The University of Surrey, Guildford, Surrey, GU2 7XH, United Kingdom.
+44 (0)1483 300800