基于蓝藻生物炭粒子电极的3维电化学系统对磺胺甲恶唑的降解  

Degradation of Sulfamethoxazole by Three-dimensional Electrochemical System Using Cyanobacteria-derived Biochar as Particle Electrodes

作　　者：张晴[1] 赵丽娜[1] 蒋欣 边博 杨维本[1] 赵俭波[3] 杨朕[1] ZHANG Qing;ZHAO Lina;JIANG Xin;BIAN Bo;YANG Weiben;ZHAO Jianbo;YANG Zhen(School of Chemistry and Materials Sci.,Nanjing Normal Univ.,Nanjing 210023,China;School of Environment,Nanjing Normal Univ.,Nanjing 210023,China;College of Life Sci.,Tarim Univ.,Alar 843300,China)

机构地区：[1]南京师范大学材料与化学科学学院,江苏南京210023 [2]南京师范大学环境学院,江苏南京210023 [3]塔里木大学生命科学学院,新疆阿拉尔843300

出　　处：《工程科学与技术》2024年第4期24-34,共11页Advanced Engineering Sciences

基　　金：国家自然科学基金项目(51978341);新疆生产建设兵团南疆重点研发项目(2022DB025);江苏省生态环境科研项目(2022003);江苏省“青蓝工程”优秀青年骨干教师项目;教育部产学协同育人项目(220602905023838)。

摘　　要：遵循“以废治废”理念,以机械打捞后的太湖蓝藻这一典型固废为原料,采用高温热解和酸/碱处理的方法制备了环境友好的蓝藻基生物炭,并将其作为3维电化学系统(3DES)中的粒子电极,用于高效催化氧化降解去除水中的典型抗生素磺胺甲恶唑(SMX)。经过热解及酸/碱改性后,生物炭更大的比表面积和更丰富的孔道结构提高了SMX在粒子电极表面的富集能力;而蓝藻中原有的铁、氮等元素掺杂在热解生物炭中有效提高了体系中活性氧物种的产生量,使得体系对SMX的去除率和矿化率均显著提高。在最佳制备和运行条件下(粒子电极制备条件:700℃热解和碱改性;3DES运行条件:电流600mA、溶液pH为6、粒子电极用量1.00g/L、水流速300 mL/min、电解质Na_(2)SO_(4)浓度50mmol/L),SMX在120min内去除率可达96%以上;6h后,水体总有机碳(TOC)去除率可达94%。机理研究表明,3DES中,SMX降解的间接氧化作用(占比84.32%)大于直接氧化作用(占比15.68%);间接氧化中,HO^(·)和SO_(4)^(·-)在体系中均被检出,但是,未检测出超氧自由基和单线态氧;而相较于SO_(4)^(·-),HO^(·)对SMX的降解占主导地位(间接氧化中HO占比87.31%)。在连续循环使用6次后,3DES对SMX的去除效率仍能保持在85%以上。研究结果为基于蓝藻生物炭粒子电极的3DES在水处理领域的应用提供了技术支撑和理论依据。Following the concept of“treating waste using waste”,this study uses cyanobacteria in the Tai Lake after mechanical salvage as raw materials to prepare environmentally friendly cyanobacteria-based biochar through high temperature,oxygen-limited pyrolysis,and acid/alkali treatment.The obtained biochar is then utilized as particle electrodes in a three-dimensional electrochemical system(3DES)to remove the typical antibiotic sulfamethoxazole(SMX)from water.After pyrolysis and acid/alkali treatment,the biochar exhibits a larger specific surface area and a more abundant pore structure,which enhances the enrichment of SMX on the surface of particle electrodes.The original iron and nitrogen ele-ments in cyanobacteria form a doping structure in the resulting biochar,significantly enhancing the generation of reactive oxygen species and im-proving the removal and mineralization efficiencies of SMX.The optimized biochar is prepared at a pyrolysis temperature of 700℃ and sub-sequently modified using alkali.The optimized operational conditions of 3DES involve a current of 600 mA,a pH of 6,a particle electrode dosage of 1.00 g/L,a water flow rate of 300 mL/min,and an electrolyte Na2SO4 concentration of 50 mm.The removal efficiency for SMX can exceed 96% within 120 min,and the total organic carbon(TOC)removal efficiency can reach 94% after 6 h.Mechanism studies indicated that indirect oxidation,accounting for 84.32% of SMX degradation,is more significant than direct oxidation,which accounts for 15.68%;both HO^(·)and SO_(4)^(·-) are detected in the system,yet neither^(1)O_(2)nor O_(2)^(-) is detected;compared to SO_(4)^(·-),HO^(·)in indirect oxidation,accounting for 87.31%,plays a dom-inant role in the 3DES.After six cycles of operation,the degradation efficiency of 3DES for SMX removal remains above 85%.This work provides technical support and a theoretical basis for applying 3DES based on cyanobacterial biochar particle electrodes in water treatment.

关 键 词：蓝藻基粒子电极 3维电化学系统 抗生素 降解 生物炭 

分 类 号：X52[环境科学与工程—环境工程]