摘要
通过批吸附动力学、等温吸附试验,并结合X射线光电子能谱(XPS)技术和衰减全反射-傅里叶变换红外光谱(ATRFTIR),揭示不同pH下左氧氟沙星(LEV)在铁氧化物表面的吸附机制。结果表明:溶液pH对LEV在针铁矿表面的吸附影响较大,不同pH下,其吸附动力学更符合准二级动力学模型(R^(2)>0.98)。在pH为4时,3 h左右达到吸附平衡,而在pH为8时,12 h达到吸附平衡,并且pH为4的吸附量约是pH为8的2倍。XPS和ATR-FTIR的结果一致表明,静电作用和化学吸附是其主要吸附机制,在低pH(pH为4)时,LEV在针铁矿表面主要以单核双齿形态被吸附,在高pH(pH为8)时,主要以双核双齿形态被吸附。在中间pH(pH为6)时,由于静电排斥作用,导致其吸附量最大。
Batch adsorption kinetics,adsorption isotherm experiments,X-ray photoelectron spectroscopy(XPS)technology,and attenuated total reflection-fourier transform infrared spectroscopy(ATR-FTIR)were used in this investigation to gain insights into the levofloxacin(LEV)adsorption process on the surface of iron oxides at various pH values.Solution pH had a significant impact on LEV adsorption,and adsorption kinetics at different pH values were a good fit for the pseudo-second-order kinetic model(R^(2)>0.98).At pH 4,adsorption equilibrium was reached in about 3 h,whereas it took 12 h at pH 8.The total amount adsorbed at pH 4 was almost twice of that at pH 8.XPS and ATR-FTIR results consistently indicated that electrostatic interaction and chemical adsorption were the main adsorption mechanisms.LEV was mainly adsorbed in bidentate binuclear form on the goethite surface at low pH(pH<6),and bidentate binuclear at high pH(pH>8).Adsorption capacity was greatest at intermediate pH(pH=6)due to electrostatic repulsion.
作者
刘自超
任亚男
周文静
刘春晖
李孜娴
杨金康
孙齐状
王龙
赵鹏
LIU Zichao;REN Yanan;ZHOU Wenjing;LIU Chunhui;LI Zixian;YANG Jinkang;SUN Qizhuang;WANG Long;ZHAO Peng(College of Resources and Environment,Henan Agricultural University,Zhengzhou 450000,China;College of Horticulture,Henan Agricultural University,Zhengzhou 450002,China)
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2023年第2期362-372,共11页
Journal of Agro-Environment Science
基金
国家自然科学基金青年科学基金(42007103)
河南省科技攻关项目(222102110048)
河南省研究生教育改革与质量提升工程项目(HNYJS2020KC17)
河南农业大学科技创新基金(KJCX2020A18)
河南省大学生创新创业训练计划项目(202110466029)。
