Wang Qirui, Shi Yixuan, Lv Shiyi, Liang Ying, Xiao Pengfei
College of Forestry, Northeast Forestry University Harbin 150040 China
RSC Adv. 2021 May 22;11(30):18525-18538. doi: 10.1039/d1ra01640g. eCollection 2021 May 19.
The recycling of agricultural and food waste is an effective way to reduce resource waste and ameliorate the shortage of natural resources. The treatment of antibiotic wastewater is a current research hotspot. In this study, waste tea residue was used as a raw material to prepare biochar (T-BC) and loaded with FeO as a catalyst to activate peroxymonosulfate (PMS) for oxidative degradation of tetracycline hydrochloride (TCH). Analysis techniques such as BET, SEM, XRD, FT-IR, XPS and VSM indicated that the heterogeneous catalyst (FeO@T-BC) with good surface properties and magnetic properties was successfully prepared. The results of batch-scale experiments illustrated that when the dose of the FeO@T-BC catalyst was 1 g L, the concentration of PMS was 1 g L, and the initial pH was 7, the degradation rate of TCH with a concentration of 50 mg L reached 97.89% after 60 minutes of reaction. When the initial pH was 11, the degradation rate of TCH reached 99.86%. After the catalyst was recycled four times using an external magnet, the degradation rate of TCH could still reach 71.32%. The data of removal of TCH could be best fitted by a pseudo-first-order model. The analysis of the degradation mechanism through a free radical quenching experiment and EPR analysis, as well as the exploration of TCH intermediate products and reaction paths through the LC-MS method, all confirmed that the FeO@T-BC prepared by this method is expected to become a cost-effective and environmentally friendly heterogeneous catalyst for activating persulfate degradation of tetracycline antibiotics.
农业和食品废弃物的循环利用是减少资源浪费、缓解自然资源短缺的有效途径。抗生素废水处理是当前的研究热点。本研究以废茶渣为原料制备生物炭（T-BC），并负载FeO作为催化剂来活化过一硫酸盐（PMS）以氧化降解盐酸四环素（TCH）。BET、SEM、XRD、FT-IR、XPS和VSM等分析技术表明，成功制备了具有良好表面性质和磁性的非均相催化剂（FeO@T-BC）。批次实验结果表明，当FeO@T-BC催化剂投加量为1 g/L、PMS浓度为1 g/L、初始pH为7时，浓度为50 mg/L的TCH在反应60分钟后的降解率达到97.89%。当初始pH为11时，TCH的降解率达到99.86%。使用外部磁铁对催化剂进行4次循环后，TCH的降解率仍可达到71.32%。TCH去除数据最适合用准一级模型拟合。通过自由基淬灭实验和EPR分析对降解机理进行分析，以及通过LC-MS方法对TCH中间产物和反应路径进行探索，均证实了该方法制备的FeO@T-BC有望成为一种经济高效且环境友好的用于活化过硫酸盐降解四环素类抗生素的非均相催化剂。
