Enhanced degradation of carbon tetrachloride by surfactant-modified zero-valent iron.
Sorption of carbon tetrachloride (CT) by zero-valent iron (ZVI) is the rate-limiting step in the degradation of CT, so the sorption capacity of ZVI is of great importance. This experiment was aimed at enhancing the sorption of CT by ZVI and the degradation rate of CT by modification of surfactants. This study showed that ZVI modified by cationic surfactants has favorable synergistic effect on the degradation of CT. The CT degradation rate of ZVI modified by cetyl pyridinium bromide (CPB) was higher than that of the unmodified ZVI by 130%, and the CT degradation rate of ZVI modified by cetyl trimethyl ammonium bromide (CTAB) was higher than that of the unmodified ZVI by 81%. This study also showed that the best degradation effect is obtained at the near critical micelle concentrations (CMC) and that high loaded cationic surfactant does not have good synergistic effect on the degradation due to its hydrophilicity and the block in surface reduction sites. Furthermore degradation of CT by ZVI modified by nonionic surfactant has not positive effect on the degradation as the ionic surfactant and the ZVI modified by anionic surfactant has hardly any obvious effects on the degradation.
Meng
Ya-feng
YF
Institute of Environmental Engineering, Zhejiang University, Hangzhou 310027, China.
Guan
Bao-hong
BH
Wu
Zhong-biao
ZB
Wang
Da-hui
DH
D002251:Carbon Tetrachloride / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry*; D013501:Surface-Active Agents / Q000737:chemistry*; D014876:Water Pollution / Q000517:prevention & control
D013501:Surface-Active Agents; D002251:Carbon Tetrachloride; D007501:Iron