State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, PR China.
J Hazard Mater. 2010 Jun 15;178(1-3):867-74. doi: 10.1016/j.jhazmat.2010.02.018. Epub 2010 Feb 11.
This study focused on the effects of 2,4-dichlorphenol (2,4-DCP) initial concentration, initial pH value, applied current density and supporting electrolyte in water on 2,4-DCP degradation over Er-chitosan-PbO(2) electrode in a batch reactor. The results showed that higher initial 2,4-DCP concentration promoted the instantaneous current efficiency (ICE) and average current efficiency (ACE), however, 2,4-DCP degradation rate was inhibited although the removal amount was increased. In the range of initial pH between 3.3 and 12.5, both the highest and the lowest pH conditions favored 2,4-DCP degradation. With the increase of applied current density (1-10 mA/cm(2)), 2,4-DCP degradation efficiency increased initially, however, no significant change was observed afterwards. An acidic condition and higher applied current density were more beneficial to COD removal. The removal efficiency of 2,4-DCP was increased when NaCl was used as the supporting electrolyte instead of Na(2)SO(4) or NaNO(3). The increase of supporting electrolyte (NaSO(4)) concentration (0.01-0.05 mol/L) advanced 2,4-DCP degradation, COD removal and ACE. However, obvious inhibitory effect was exhibited when NaSO(4) concentration increased over a certain value (0.1 mol/L). The activity of Er-chitosan-PbO(2) electrode for 2,4-DCP degradation kept steady after repeated use.
本研究聚焦于 2,4-二氯苯酚（2,4-DCP）初始浓度、初始 pH 值、施加电流密度和支持电解质在水中对 Er-壳聚糖-PbO2 电极在批式反应器中降解 2,4-DCP 的影响。结果表明，较高的初始 2,4-DCP 浓度促进了瞬时电流效率（ICE）和平均电流效率（ACE），然而，尽管去除量增加，2,4-DCP 的降解速率却受到抑制。在初始 pH 值为 3.3 到 12.5 的范围内，最高和最低 pH 值条件都有利于 2,4-DCP 的降解。随着施加电流密度（1-10 mA/cm2）的增加，2,4-DCP 的降解效率最初增加，但之后没有明显变化。酸性条件和较高的施加电流密度更有利于 COD 的去除。当使用 NaCl 作为支持电解质而不是 Na2SO4 或 NaNO3 时，2,4-DCP 的去除效率增加。支持电解质（NaSO4）浓度（0.01-0.05 mol/L）的增加促进了 2,4-DCP 的降解、COD 的去除和 ACE。然而，当 NaSO4 浓度超过一定值（0.1 mol/L）时，会表现出明显的抑制作用。Er-壳聚糖-PbO2 电极的 2,4-DCP 降解活性在重复使用后保持稳定。
