State Key Laboratory of Urban Water Resource and Environment, School of Environment , Harbin Institute of Technology , Harbin 150090 , China.
Technology R & D Center for Environmental Engineering , Dongguan University of Technology , Dongguan 523808 , China.
Environ Sci Technol. 2019 May 7;53(9):5282-5291. doi: 10.1021/acs.est.9b00180. Epub 2019 Apr 23.
Sulfamethoxazole (SMX) is a broad-spectrum antibiotic and was largely used in breeding industry. The reaction rate of SMX with KMnO is slow, and the adsorption efficiency of biochar for SMX was inferior (less than 11% in 30 min). By adding biochar powder into SMX solution with the addition of permanganate, the oxidation ratio of SMX surged to 97% in 30 min, and over 58% of the total organic carbon (TOC) was simultaneously removed. KMnO interacted with biochar and resulted in the formation of highly oxidative intermediate manganese species, which transformed SMX into hydrolysis products, oxygen-transfer products, and self-coupling products. Brunauer-Emmett-Teller (BET) analysis showed that surface area, total pore volume, and micropore volume of biochar increased by 32.1%, 36.4%, and 80.6%, respectively, after reaction process. This in situ activation of biochar with KMnO enhanced its adsorption capacity and led to great improvement of TOC removal. Besides KMnO oxidation, biochar also enhanced TOC removal in Mn(III) oxidation (KMnO+ bisulfite) and ozonization of SMX. Considering that KMnO could react with biochar and result in the formation of intermediate manganese species, while biochar can be simultaneously activated and exhibit high capacity for organic adsorption, the combination of biochar with the chemical/advanced oxidation could be a promising process for the removal of environmental pollutants.
磺胺甲恶唑（SMX）是一种广谱抗生素，曾大量应用于养殖行业。SMX 与 KMnO 的反应速率较慢，生物炭对 SMX 的吸附效率较差（在 30 分钟内低于 11%）。通过在含有高锰酸盐的 SMX 溶液中添加生物炭粉末，SMX 的氧化率在 30 分钟内迅速上升至 97%，同时去除了超过 58%的总有机碳（TOC）。KMnO 与生物炭相互作用，形成了具有高氧化活性的中间锰物种，将 SMX 转化为水解产物、氧转移产物和自偶联产物。BET 分析表明，反应后生物炭的比表面积、总孔体积和微孔体积分别增加了 32.1%、36.4%和 80.6%。原位 KMnO 活化生物炭增强了其吸附能力，从而极大地提高了 TOC 的去除率。除了 KMnO 氧化外，生物炭还增强了 Mn(III)氧化（KMnO+亚硫酸氢盐）和 SMX 的臭氧氧化过程中的 TOC 去除。考虑到 KMnO 可以与生物炭反应形成中间锰物种，同时生物炭可以被同时激活并表现出对有机吸附的高容量，因此生物炭与化学/高级氧化的结合可能是去除环境污染物的一种很有前途的工艺。
