State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing, 100083, PR China; School of Earth Sciences and Resources, China University of Geosciences, Beijing, 100083, PR China.
State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing, 100083, PR China; School of Earth Sciences and Resources, China University of Geosciences, Beijing, 100083, PR China; China Household Elect Appliance Res Inst CHEARDI, Beijing, 100053, PR China.
Chemosphere. 2023 Jul;329:138589. doi: 10.1016/j.chemosphere.2023.138589. Epub 2023 Apr 4.
Nonradical persulfate oxidation techniques have evolved as a new contaminated water treatment approach due to its great tolerance to water matrixes. The catalysts of CuO-based composites have received much attention in that aside from SO/OH radicals, the nonradicals of singlet oxygen (O) can be also generated during persulfate activation via CuO. However, the issues regarding particles aggregation and metal leaching from the catalysts during the decontamination process remain to be addressed, which could have a remarkable impact on the catalytic degradation of organic pollutants. Accordingly in the present study, a novel biochar-supported bimetallic FeO-CuO catalyst (CuFeBC) was facilely developed to activate peroxodisulfate (PDS) for the degradation of norfloxacin (NOR) in aqueous solution. The results showed CuFeBC has a superior stability against metal ions Cu/Fe leaching, and NOR (30 mg L) was degraded at 94.5% within 180 min in the presence of CuFeBC (0.5 g L) and PDS (6 mM) in pH 8.5. The scavenging of reactive oxygen species and electron spin resonance analysis revealed that O dominated the degradation of NOR. Compared with pristine CuO-FeO, the interaction between biochar substrate and metal particles could significantly enhance the contribution of the nonradical pathway to NOR degradation from 49.6% to 84.7%. Biochar substrate could efficiently reduce the leaching of metal species from the catalyst, thereby maintaining excellent catalytic activity and lasting reusability of the catalyst. These findings could enlighten new insights into fine-tuning radical/nonradical processes from CuO-based catalysts for the efficient remediation of organic contaminants in polluted water.
非自由基过硫酸盐氧化技术因其对水基质的高耐受性而发展成为一种新的污染水处理方法。氧化铜基复合材料的催化剂受到了广泛关注，因为除了 SO/OH 自由基外，过硫酸盐活化过程中还可以通过氧化铜产生单线态氧 (O) 的非自由基。然而，在去污过程中，催化剂的颗粒聚集和金属浸出问题仍然存在，这可能对有机污染物的催化降解产生显著影响。因此，本研究中，开发了一种新型的生物炭负载双金属 FeO-CuO 催化剂 (CuFeBC) 来活化过二硫酸盐 (PDS)，用于水溶液中诺氟沙星 (NOR) 的降解。结果表明，CuFeBC 具有优异的稳定性，可防止金属离子 Cu/Fe 浸出，在 pH 8.5 下，当 CuFeBC（0.5 g L）和 PDS（6 mM）存在时，NOR（30 mg L）在 180 min 内降解率达到 94.5%。活性氧物种的猝灭和电子自旋共振分析表明，O 主导了 NOR 的降解。与原始的 CuO-FeO 相比，生物炭基质与金属颗粒之间的相互作用可将非自由基途径对 NOR 降解的贡献从 49.6%显著提高到 84.7%。生物炭基质可有效减少催化剂中金属物种的浸出，从而保持催化剂优异的催化活性和持久的可重复使用性。这些发现为从氧化铜基催化剂精细调控自由基/非自由基过程以有效修复污染水中的有机污染物提供了新的思路。
