State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China.
State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process, East China University of Science and Technology, Shanghai 200237, China.
Water Res. 2022 Aug 1;221:118792. doi: 10.1016/j.watres.2022.118792. Epub 2022 Jun 24.
S(IV)-based advanced oxidation process has been applied for contaminants remediation. However, as a traditional source of sulfite (SO), NaSO is extremely soluble in water, resulting in a high concentration of SO to quench the generated reactive oxygen species (ROS). In this work, CaSO was introduced instead of NaSO for its slow-released SO ability and Fe(III)/CaSO system was established for the removal of trichloroethylene (TCE) and other organic contaminants. The degradation efficiency of TCE reached 94.0% and TCE could be completely dechlorinated and mineralized, while the removal of other contaminants was all over 85.0% at the optimal tested conditions. Through EPR detection, ROS scavenging and probe tests, and quantification of ROS amounts, it was concluded that the dominant ROS in Fe(III)/CaSO system were SO· and O, of which the transformation mechanism of SO· to O was revealed and demonstrated comprehensively. The synergistic contaminants degradation performance in different sulfur-iron-containing systems and in the presence of oxidants was evaluated. The effects of various solution conditions were assessed and Fe(III)/CaSO system was of higher resistance on complex solution matrixes, suggesting the broad-spectrum and application perspective for the remediation of complex contaminants in actual water.
基于 S(IV) 的高级氧化工艺已被应用于污染物的修复。然而，作为亚硫酸盐（SO）的传统来源，NaSO 极易溶于水，导致 SO 浓度过高，从而猝灭生成的活性氧物质（ROS）。在这项工作中，引入 CaSO 代替 NaSO，利用其缓慢释放 SO 的能力，并建立 Fe(III)/CaSO 体系，以去除三氯乙烯（TCE）和其他有机污染物。在最佳测试条件下，TCE 的降解效率达到 94.0%，TCE 可完全脱氯和矿化，而其他污染物的去除率均超过 85.0%。通过 EPR 检测、ROS 清除和探针测试以及 ROS 量的定量分析，得出 Fe(III)/CaSO 体系中的主要 ROS 为 SO·和 O，其中揭示并全面论证了 SO·向 O 的转化机制。评估了不同含硫-铁体系和氧化剂存在下协同污染物降解性能。评估了各种溶液条件的影响，Fe(III)/CaSO 体系对复杂溶液基质具有更高的抵抗力，这表明该体系在实际水体中修复复杂污染物具有广谱性和应用前景。
