Reaction Mechanism for Chlorination of Urea

被引:78
作者
Blatchley, Ernest R., III [1 ]
Cheng, Mingming
机构
[1] Purdue Univ, Sch Civil Engn, W Lafayette, IN 47907 USA
关键词
DISINFECTION BY-PRODUCTS; GAS-PHASE CHEMISTRY; STABILITY; WATER;
D O I
10.1021/es102423u
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
Experiments were conducted to elucidate the mechanism of the reaction between free chlorine and urea. In combination with findings of previous investigations, the results of these experiments indicate a process by which urea undergoes multiple N-chlorination steps. The first of these steps results in the formation of N-chlorourea; this step appears to require Cl(2) to proceed and is the overall rate-limiting step in the reaction for conditions that correspond to most swimming pools. N-Chlorourea then appears to undergo further chlorine substitution; the fully N-chlorinated urea molecule is hypothesized to undergo hydrolysis and additional chlorination to yield NCl(3) as an intermediate. NCl(3) is hydrolyzed to yield NH(2)Cl and NHCl(2), with subsequent decay to stable end products, including N(2) and NO(3)(-). Conversion of urea-N to nitrate is pH-dependent The pattern of nitrate yield is believed to be attributable to the fact that when urea serves as the source of reduced-N, entry into the reactions that describe chlorination of ammoniacal nitrogen is through NCl(3), whereas when NH(3) is the source of reduced-N, entry to these reactions is through NH(2)Cl.
引用
收藏
页码:8529 / 8534
页数:6
相关论文
共 18 条
[1]   Infant swimming practice, pulmonary epithelium integrity, and the risk of allergic and respiratory diseases later in childhood [J].
Bernard, Alfred ;
Carbonnelle, Sylviane ;
Dumont, Xavier ;
Nickmilder, Marc .
PEDIATRICS, 2007, 119 (06) :1095-1103
[2]   Effect of intense swimming training on rhinitis in high-level competitive swimmers [J].
Bougault, V. ;
Turmel, J. ;
Boulet, L. P. .
CLINICAL AND EXPERIMENTAL ALLERGY, 2010, 40 (08) :1238-1246
[3]  
CHATTAWAY FD, 1908, CHEM NEWS, V98, P285
[4]   Prevalence of Ocular, Respiratory and Cutaneous Symptoms in Indoor Swimming Pool Workers and Exposure to Disinfection By-Products (DBPs) [J].
Fantuzzi, Guglielmina ;
Righi, Elena ;
Predieri, Guerrino ;
Giacobazzi, Pierluigi ;
Mastroianni, Katia ;
Aggazzotti, Gabriella .
INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH, 2010, 7 (04) :1379-1391
[5]   REACTION SCHEME FOR THE CHLORINATION OF AMMONIACAL WATER [J].
JAFVERT, CT ;
VALENTINE, RL .
ENVIRONMENTAL SCIENCE & TECHNOLOGY, 1992, 26 (03) :577-586
[6]   The fate of chlorine and organic materials in swimming pools [J].
Judd, SJ ;
Bullock, G .
CHEMOSPHERE, 2003, 51 (09) :869-879
[7]   The Good, the Bad, and the Volatile: Can We Have Both Healthy Pools and Healthy People? [J].
Lakind, Judy S. ;
Richardson, Susan D. ;
Blount, Benjamin C. .
ENVIRONMENTAL SCIENCE & TECHNOLOGY, 2010, 44 (09) :3205-3210
[8]  
Lentner C., 1981, Geigy scientific tables, V1
[9]  
LI J, 2007, ENVIRON SCI TECHNOL, V41, P6372
[10]  
PALIN AT, 1950, WATER WATER ENG, V53