Key Laboratory of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun 130021, China.
J Hazard Mater. 2013 Oct 15;261:500-11. doi: 10.1016/j.jhazmat.2013.07.040. Epub 2013 Jul 26.
The photoconversion of 4-chlorophenol (4-CP) in a simulated sunlight-Fenton system was investigated in ice and aqueous solution. It was found that the hydroxyl radical (OH) had an important effect on the photoconversion of 4-CP in both phases, but the effects of Cl(-), SO4(2-), NO3(-), and HCO3(-) were different. In aqueous solution, the photoconversion efficiency of 4-CP was proportional to the OH concentration, and hence, Cl(-) and HCO3(-) as OH scavengers prohibited the photoconversion; SO4(2-) had little effect; NO3(-) promoted the process under certain conditions owing to OH being generated by the photolysis of NO3(-). In ice, however, the photoconversion efficiency of 4-CP was not proportional to the concentration of OH. The photoconversion efficiency of 4-CP increased with increasing concentrations of all ions, although the OH remained almost constant, only increasing or decreasing slightly. This provides new evidence for the presence of a quasi-liquid layer (QLL). Hydroxylation products were detected in both phases. All photoproducts in aqueous solution contained only a single benzene ring, whereas in ice, dimers were also detected.
在模拟阳光芬顿体系中，研究了 4-氯苯酚（4-CP）在冰和水溶液中的光转化。结果发现，羟基自由基（OH）在两相中对 4-CP 的光转化都有重要影响，但 Cl(-)、SO4(2-)、NO3(-)和 HCO3(-)的影响不同。在水溶液中，4-CP 的光转化效率与 OH 浓度成正比，因此，作为 OH 清除剂的 Cl(-)和 HCO3(-)会抑制光转化；SO4(2-)的影响较小；在一定条件下，NO3(-)会通过光解生成 OH 而促进该过程。然而，在冰相中，4-CP 的光转化效率与 OH 浓度不成正比。尽管 OH 几乎保持不变，只是略有增加或减少，但 4-CP 的光转化效率随所有离子浓度的增加而增加。这为存在准液相层（QLL）提供了新的证据。在两相中都检测到了羟基化产物。水溶液中的所有光产物仅含有单个苯环，而在冰相中，还检测到了二聚体。
