Liu Xiaowei, Chen Chen, Chen Peng, Wang Lili
Zhejiang Key Laboratory of Drinking Water Safety and Distribution Technology, Zhejiang University Hangzhou 310058 China
Ocean College, Zhejiang University Hangzhou 310058 China.
RSC Adv. 2023 Jan 20;13(5):3103-3111. doi: 10.1039/d2ra06865f. eCollection 2023 Jan 18.
To address the concern about residual antibiotics in effluent of sewage treatment plants, cobalt silicate (CoSiO ) was prepared by hydrothermal method and employed as an activator of peroxymonosulfate (PMS) for the rapid degradation of antibiotics. Taking sulfamethoxazole (SMX) and tetracycline (TC) as representatives of antibiotics, the effects of operation parameters (CoSiO and PMS dosage) and water quality parameters (temperature, solution pH, bicarbonate, chloride, and natural organic matter) on degradation of target pollutants by a CoSiO activated PMS process (CoSiO /PMS) were investigated. The mechanism involved in the interaction of CoSiO and PMS was also elucidated. The results indicated that CoSiO /PMS can degrade SMX and TC at fast pseudo-first-order rate constants (0.47 and 0.56 min respectively) under optimal conditions. Increasing the dosage of PMS and CoSiO appropriately was beneficial to the degradation of antibiotics. Chloride, bicarbonate, and HA showed negative effects on the degradation process due to their free radical-scavenging ability and were ranked as chloride < bicarbonate < HA. Abundant [triple bond, length as m-dash]Co-OH and oxygen vacancies on the surface of CoSiO contributed to its excellent activation capability towards PMS. The radical scavenging experiments indicated that target pollutant degradation mainly resulted from the attack of sulfate radicals (43.0% contribution) and hydroxyl radicals (52.9% contribution). The practicality of CoSiO /PMS was verified by continuous flow test. This study provides a cheap, highly efficient, and feasible advanced depollution method based on CoSiO .
为解决污水处理厂出水残留抗生素的问题，采用水热法制备了硅酸钴（CoSiO₄），并将其用作过一硫酸盐（PMS）的活化剂以快速降解抗生素。以磺胺甲恶唑（SMX）和四环素（TC）作为抗生素的代表，研究了操作参数（CoSiO₄和PMS用量）和水质参数（温度、溶液pH值、碳酸氢盐、氯化物和天然有机物）对CoSiO₄活化PMS工艺（CoSiO₄/PMS）降解目标污染物的影响。还阐明了CoSiO₄与PMS相互作用的机制。结果表明，在最佳条件下，CoSiO₄/PMS能以快速的准一级速率常数（分别为0.47和0.56 min⁻¹）降解SMX和TC。适当增加PMS和CoSiO₄的用量有利于抗生素的降解。氯化物、碳酸氢盐和腐殖酸（HA）由于其自由基清除能力对降解过程有负面影响，其影响程度排序为氯化物＜碳酸氢盐＜HA。CoSiO₄表面丰富的[三键，长度如m破折号]Co-OH和氧空位有助于其对PMS具有优异的活化能力。自由基清除实验表明，目标污染物的降解主要源于硫酸根自由基的攻击（贡献43.0%）和羟基自由基的攻击（贡献52.9%）。通过连续流试验验证了CoSiO₄/PMS的实用性。本研究提供了一种基于CoSiO₄的廉价、高效且可行的深度除污方法。
