Electrokinetic movement of multiple chlorobenzenes in contaminated soils in the presence of β-cyclodextrin  

作　　者：YUAN Song-hu WAN Jin-zhong LU Xiao-hua 

机构地区：[1]School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.

出　　处：《Journal of Environmental Sciences》2007年第8期968-976,共9页环境科学学报（英文版）

基　　金：Project supported by the Education Ministry of China(No.104250);the Natural Science Foundation of Hubei Province(No.2006ABD005).

摘　　要：This study investigated the electrokinetic （EK） behavior of multiple chlorobenzenes, including 1,2,3,4-tetrachlorobenzene （TeCB）, 1,2,4,5-tetrachlorobenzene （i-TeCB）, and 1,2,3-trichlorobenzene （TCB） in contaminated clayed soils. The effect of β-cyclodextrin （β- CD） on the EK removal of the chlorobenzenes was studied. The largest removal was obtained when Na2CO3/NaHCO3 buffer was used as anodic purging solution without β-CD. The removal efficiencies were related to the aqueous solubilities of chlorobenzenes. With the same cumulative electroosmotic flow, greater solubility led to higher removal efficiency. The addition of β-CD inhibited the EK removal efficiency of all chlorobenzenes. The inhibition increased with the increase of β-CD concentration. With the same β-CD concentration, the inhibition increased with the rise of electric potential. It was found that the inclusion compounds between β-CD and chlorobenzenzes were less soluble than chlorobenzenes. The formation of the less soluble inclusion compounds reduced the aqueous solubility of chlorobenzenes and led to the partial immobilization of the chlorobenzenes that desorbed from soil. It was feasible to use the EK technology to remove chlorobenzenes in contaminated soils using water as the anodic flushing solution. The addition of β-CD was not recommended for the EK removal of chlorobenzenes.This study investigated the electrokinetic （EK） behavior of multiple chlorobenzenes, including 1,2,3,4-tetrachlorobenzene （TeCB）, 1,2,4,5-tetrachlorobenzene （i-TeCB）, and 1,2,3-trichlorobenzene （TCB） in contaminated clayed soils. The effect of β-cyclodextrin （β- CD） on the EK removal of the chlorobenzenes was studied. The largest removal was obtained when Na2CO3/NaHCO3 buffer was used as anodic purging solution without β-CD. The removal efficiencies were related to the aqueous solubilities of chlorobenzenes. With the same cumulative electroosmotic flow, greater solubility led to higher removal efficiency. The addition of β-CD inhibited the EK removal efficiency of all chlorobenzenes. The inhibition increased with the increase of β-CD concentration. With the same β-CD concentration, the inhibition increased with the rise of electric potential. It was found that the inclusion compounds between β-CD and chlorobenzenzes were less soluble than chlorobenzenes. The formation of the less soluble inclusion compounds reduced the aqueous solubility of chlorobenzenes and led to the partial immobilization of the chlorobenzenes that desorbed from soil. It was feasible to use the EK technology to remove chlorobenzenes in contaminated soils using water as the anodic flushing solution. The addition of β-CD was not recommended for the EK removal of chlorobenzenes.

关 键 词：CHLOROBENZENES ELECTROKINETIC soil remediation β-cyclodextrin （β-CD） 

分 类 号：X53[环境科学与工程—环境工程]