中国化学工程学报(英文版)
中國化學工程學報(英文版)
중국화학공정학보(영문판)
CHINESE JOURNAL OF CHEMICAL ENGINEERING
2013年
12期
1386-1390
,共5页
张瑞玲%路晓霞%焦刚珍%秦松岩%QIN Songyan
張瑞玲%路曉霞%焦剛珍%秦鬆巖%QIN Songyan
장서령%로효하%초강진%진송암%QIN Songyan
hydrogen%electrode%reductive%dechlorination%capping
In situ capping is an attractive and cost-effective method for remediation of contaminated sediments, but few studies on enhancing contaminant degradation in sediment caps have been reported, especially for chlorin-ated benzenes. Electrically enhanced bioactive barrier is a new process for in situ remediation for reducible com-pounds in soil or sediments. The primary objective of this study is to determine if electrodes in sediment could cre-ate a redox gradient and provide electron acceptor/donor to stimulate degradation of chlorinated contaminant. The results demonstrate that graphite electrodes lead to sustainable evolution of hydrogen, displaying zero-order kinetics in the initial stages with different voltages. The constant rates of hydrogen evolution at 3, 4, and 5 V are 1.05, 2.54, and 4.3 nmol·L-1·d-1, respectively. Even higher voltage can produce more hydrogen, but it could not keep long time because the over potentials on electrode surfaces prevent its function. The study shows that 4 V is more appropriate for hydrogen evolution. The measured and evaluated concentration of 1,2,3,5-tetrachlorobenzene in pore water of sediment and concentration of sulfate show that dechlorination is inhibited at higher concentration of sulfate.