Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 1H9, Canada.
Faculty of Pharmacy and Pharmaceutical Sciences(,) University of Alberta, Edmonton, Alberta T6G 2H5, Canada.
Sci Total Environ. 2021 Jul 10;777:146138. doi: 10.1016/j.scitotenv.2021.146138. Epub 2021 Mar 1.
Powdered activated carbon (PAC) is a strong adsorbent also capable of catalyzing ozonation processes. Ozone (O) and PAC were simultaneously applied to treat a mixture of 17 micropollutants (MPs) at low concentrations, including 13 compounds that were studied for the first time by simultaneous addition of O and PAC system. Synergy and catalysis improved the removals and specific degradation rates of MPs in the first minute of the treatment. Radical probing experiments showed that scavenging hydroxyl radicals (OH) did not have a significant impact on the removals, while scavenging other reactive oxygen species was more influential. A detailed study by electron paramagnetic resonance spectroscopy ascertained that the decomposition of ozone in presence of PAC at neutral pH did not boost the generation of free OH. Instead, adsorbed OH was likely produced as PAC-HO along with other oxidizing species resulting from adsorbed singlet oxygen and superoxide radicals.
粉末状活性炭（PAC）是一种吸附能力很强的物质，同时也能催化臭氧氧化过程。臭氧（O）和 PAC 同时用于处理浓度较低的 17 种微污染物（MPs）混合物，其中包括 13 种首次通过同时添加 O 和 PAC 系统进行研究的化合物。协同作用和催化作用提高了处理开始的第一分钟内 MPs 的去除率和特定降解速率。自由基探针实验表明，清除羟基自由基（OH）对去除率没有显著影响，而清除其他活性氧物种的影响更大。电子顺磁共振波谱的详细研究确定，中性 pH 下 PAC 存在时臭氧的分解并没有促进游离 OH 的生成。相反，可能是在 PAC-HO 与吸附单线态氧和超氧自由基产生的其他氧化物质一起生成吸附 OH。
