College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China.
College of Environmental Science and Engineering, Donghua University, Shanghai, 201620, PR China.
Chemosphere. 2020 Sep;255:126983. doi: 10.1016/j.chemosphere.2020.126983. Epub 2020 May 6.
The instability and rapid consumption of HO limit the application of UV/HO in water treatment. Recently, calcium peroxide (CaO) has been demonstrated as an effective source of HO. However, the performance and mechanism of UV/CaO are still unknown. Herein, UV/CaO and UV/HO were compared for degradation of aniline. The removal efficiency of aniline by UV/CaO was slightly lower than that by UV/HO, which could be attributed to the light scavenger by CaO suspended particles. HO‧ was identified to participate in aniline degradation in both UV/CaO and UV/HO, while O· was only involved in UV/CaO. The efficiency of aniline degradation in UV/CaO was affected by the released HO in the system. The release and decomposition rate of HO in UV/CaO system were influenced by the CaO dosage and reaction pH, but slightly related with water matrix. Excessive CaO would scavenge aniline degradation through the released HO to react with HO‧. Acidic condition would enhance the concentration of HO in UV/CaO and promote the degradation of aniline. Cl showed slight and almost no effect on aniline degradation in UV/CaO and UV/HO systems, respectively, while HCO scavenged aniline degradation in UV/CaO. NO inhibited aniline degradation in both UV/CaO and UV/HO. Compared to UV/HO, UV/CaO shows the similar efficiency on organics removal but conquers the limitations in UV/HO, which is a promising alternative choice in water treatment.
过氧钙（CaO）作为 HO 的有效来源已被证明。然而，UV/CaO 的性能和机制仍不清楚。
在此，比较了 UV/CaO 和 UV/HO 对苯胺的降解。UV/CaO 对苯胺的去除效率略低于 UV/HO，这可能归因于 CaO 悬浮颗粒的光捕获剂。HO‧被确定参与了 UV/CaO 和 UV/HO 中苯胺的降解，而 O·仅参与了 UV/CaO。UV/CaO 中苯胺降解的效率受到系统中释放的 HO 的影响。UV/CaO 体系中 HO 的释放和分解速率受 CaO 用量和反应 pH 的影响，但与水基质关系不大。过量的 CaO 会通过释放的 HO 与 HO‧反应来捕获苯胺的降解。酸性条件会增强 UV/CaO 中 HO 的浓度，并促进苯胺的降解。Cl 对 UV/CaO 和 UV/HO 体系中苯胺的降解分别表现出轻微和几乎没有影响，而 HCO 则会捕获 UV/CaO 中的苯胺降解。NO 抑制了 UV/CaO 和 UV/HO 中苯胺的降解。与 UV/HO 相比，UV/CaO 对有机物去除的效率相当，但克服了 UV/HO 的局限性，是水处理的一种有前途的替代选择。
