Factors influencing the dechlorination of 2,4-dichlorophenol by Ni-Fe nanoparticles in the presence of humic acid.
The dechlorination of 2,4-dichlorophenol (2,4-DCP) by Ni-Fe nanoparticles in the presence of humic acid (HA) was investigated to understand the feasibility of using Ni-Fe for the in situ remediation of contaminated groundwater. 2,4-DCP was first adsorbed by Ni-Fe nanoparticles, then quickly reduced to o-chlorophenol (o-CP), p-chlorophenol (p-CP), and finally to phenol (P). However, the introduction of HA decreased the removal percentage of 2,4-DCP, as a result, the phenol production rates dropped from 86% (in the absence of HA) to 29% within 2h. Our data suggested that the dechlorination rate was dependent on a number of factors including Ni-Fe availability, Ni loading percentage over Fe, temperature, pH, and HA concentration. In particular, the removal percentage of 2,4-DCP was determined to be 100, 99, 95, 84 and 69%, for HA concentrations of 0, 5, 10, 30 and 40 mg L(-1), respectively. The kinetic calculations for the dechlorination of 2,4-DCP indicated that k values for 2,4-DCP dechlorination dropped from 0.14, 0.051, 0.039, 0.021 to 0.011 min(-1) with increasing concentrations of HA from 0, 5, 10, 30 to 40 mg L(-1).
Zhang
Zhen
Z
Department of Environmental Engineering, Zhejiang University, Hangzhou, People's Republic of China.
Cissoko
Naman
N
Wo
Jingjing
J
Xu
Xinhua
X
D002733:Chlorophenols / Q000737:chemistry*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D054879:Halogenation; D006812:Humic Substances; D007501:Iron; D053758:Nanoparticles / Q000737:chemistry*; D009532:Nickel; D019800:Phenol; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods
D002733:Chlorophenols; D006812:Humic Substances; D014874:Water Pollutants, Chemical; D019800:Phenol; D009532:Nickel; D007501:Iron; C004762:2,4-dichlorophenol