Dechlorination of pentachlorophenol by zero valent iron and modified zero valent irons

被引:249
作者
Kim, YH [1 ]
Carraway, ER [1 ]
机构
[1] Texas A&M Univ, Dept Civil Engn, Environm Engn Specialty Area, College Stn, TX 77843 USA
关键词
D O I
10.1021/es991129f
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
The disappearance of pentachlorophenol (PCP) from aqueous solutions in contact with zero valent metals (ZVMs) may be due to dechlorination reactions or sorption to ZVM-related surfaces. Previously reported results on PCP and zero valent iron measured only PCP loss from aqueous solutions and attributed this loss to reaction. In this study, the total amount of unreacted PCP, both that in aqueous solution and that sorbed to ZVM-related surfaces, was measured using a modified extraction method. PCP dechlorination was confirmed by following the appearance of tetrachlorophenol isomers. The results indicate that the rate of dechlorination is much slower than previously reported. In our experiments, electrolytic zero valent iron with a surface area of 0.12 m(2)/g resulted in an observed first-order rate constant (+/-95% confidence limits) of 3.9 (+/-0.7) x 10(-3) h(-1) or a half-life of approximately 7.4 days. Normalized to surface area, the rate constant (k(SA)) is 3.2 (+/-0.6) x 10(-4) L m(-2) h(-1). Four amended irons prepared by coating iron with palladium (Pd/Fe), platinum (Pt/Fe), nickel (Ni/Fe), and copper (Cu/Fe) were also used and showed slower removal rates as compared to unamended iron (estimated half-lives of 36-43 days). Slower reaction rates obtained with amended irons as compared to iron have not been previously reported. Overall, this study conclusively demonstrates PCP dechlorination by iron and several bimetallic ZVMs and indicates that it is essential to separate reaction end sorption processes.
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页码:2014 / 2017
页数:4
相关论文
共 36 条
[1]   Reductive transformation and sorption of cis- and trans-1,2-dichloroethene in a metallic iron-water system [J].
AllenKing, RM ;
Halket, RM ;
Burris, DR .
ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY, 1997, 16 (03) :424-429
[2]   SOLUBILITY OF PENTACHLOROPHENOL IN AQUEOUS-SOLUTIONS - THE PH EFFECT [J].
ARCAND, Y ;
HAWARI, J ;
GUIOT, SR .
WATER RESEARCH, 1995, 29 (01) :131-136
[3]   Pathways of chlorinated ethylene and chlorinated acetylene reaction with Zn(0) [J].
Arnold, WA ;
Roberts, AL .
ENVIRONMENTAL SCIENCE & TECHNOLOGY, 1998, 32 (19) :3017-3025
[4]   Chlorinated ethene reduction by cast iron: Sorption and mass transfer [J].
Burris, DR ;
Allen-King, RM ;
Manoranjan, VS ;
Campbell, TJ ;
Loraine, GA ;
Deng, BL .
JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE, 1998, 124 (10) :1012-1019
[5]   SORPTION OF TRICHLOROETHYLENE AND TETRACHLOROETHYLENE IN A BATCH REACTIVE METALLIC IRON-WATER SYSTEM [J].
BURRIS, DR ;
CAMPBELL, TJ ;
MANORANJAN, VS .
ENVIRONMENTAL SCIENCE & TECHNOLOGY, 1995, 29 (11) :2850-2855
[6]   Trichloroethylene and tetrachloroethylene reduction in a metallic iron-water-vapor batch system [J].
Campbell, TJ ;
Burris, DR ;
Roberts, AL ;
Wells, JR .
ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY, 1997, 16 (04) :625-630
[7]   Electrochemical dechlorination of 4-chlorophenol to phenol [J].
Cheng, IF ;
Fernando, Q ;
Korte, N .
ENVIRONMENTAL SCIENCE & TECHNOLOGY, 1997, 31 (04) :1074-1078
[8]   ZERO-VALENT INN-PROMOTED DECHLORINATION OF POLYCHLORINATED-BIPHENYLS [J].
CHUANG, FW ;
LARSON, RA ;
WESSMAN, MS .
ENVIRONMENTAL SCIENCE & TECHNOLOGY, 1995, 29 (09) :2460-2463
[9]   IUPAC REPORTS ON PESTICIDES .14. ENVIRONMENTAL CHEMISTRY OF PENTACHLOROPHENOL [J].
CROSBY, DG .
PURE AND APPLIED CHEMISTRY, 1981, 53 (05) :1051-1080
[10]   Reduction of vinyl chloride in metallic iron-water systems [J].
Deng, BL ;
Burris, DR ;
Campbell, TJ .
ENVIRONMENTAL SCIENCE & TECHNOLOGY, 1999, 33 (15) :2651-2656