摘要
针对水体中β-内酰胺类抗生素污染愈发严重的问题,该研究以碱改性生物炭(PBC)为前驱体,采用溶胶-凝胶法制备TiO2/BC复合材料,利用其光催化降解性能处理阿莫西林(AMX)污染废水.通过BET和FTIR对制备材料进行表征,结果表明,负载TiO2后,BET比表面积可以提高20.09倍,至110.87 m2/g,复合材料表面存在大量的含氧官能团,可提高其光催化效率.基于吸附/降解实验,探究AMX分子的光催化动力学,以及该过程的降解机制,结果表明,生物炭是提高降解性能的理想载体,所制备的PBC与凝胶配比为1∶2的TiO2/BC复合材料(TBC2)表现出较好的理化性质.Elovich动力学模型适用于模拟非均相吸附过程,TBC2处理废水过程中,2 h前以吸附作用为主,2 h后光催化降解为主要影响.光催化降解过程中,AMX分子被吸附于TBC2表面和孔隙内,为后续的自由基与非自由基降解反应创造了有利条件,且TBC2具有良好的重复利用性.该研究能够为处理β-内酰胺类抗生素废水提供一定的理论依据.
Abstract
In view of the increasingly serious pollution of β-lactam antibiotics in water,TiO2/BC composites were prepared by sol-gel method using alkali-modified biochar(PBC)as precursor,and their photocatalytic degradation performance was used to treat wastewater contaminated by amoxicillin(AMX).The prepared materials were characterized by BET and FTIR.The results showed that the BET specific surface area could be increased by 20.09 times to 110.87 m2/g after TiO2 was loaded.The presence of a large number of oxygen-containing functional groups on the surface of the composite improved its photocatalytic efficiency.Based on the adsorption/degradation experiments,the photocatalytic kinetics of AMX molecules and the degradation mechanism of this process were investigated.The results showed that biochar was an ideal carrier to improve the degradation performance,and the material prepared TiO2/BC composite(TBC2)with PBC and gel ratio of 1∶2 showed better physical and chemical properties.Elovich kinetic model is suitable for simulating the hetero-geneous adsorption process.In the process of TBC2 wastewater treatment,adsorption was the main effect before 2 h,and photocatalytic degradation was the main effect after 2 h.During the photocatalytic degradation process,AMX molecules were adsorbed on the surface and pores of TBC2,which created the favorable conditions for subsequent free radical and non-free radical degradation reactions.TBC2 has good reusability.This study will provide a theoretical basis for the treatment of β-lactam antibiotic wastewater.
基金项目
北华大学教育教学改革项目(JG2021009)
北华大学生创新创业训练计划项目(202210201036)
北华大学生创新创业训练计划项目(202310201231)
万方数据