改性废白土炭复合材料对恩诺沙星的吸附效应分析  

Adsorption effects of enrofloxacin by modified spent bleaching earth carbon composites

作　　者：朱晓丽[1] 张婷[1] 王军强 赵汉红 尚小清[1,2] 申保收 陈超 王静 ZHU Xiaoli;ZHANG Ting;WANG Junqiang;ZHAO Hanhong;SHANG Xiaoqing;SHEN Baoshou;CHEN Chao;WANG Jing(School of City and Environment,Northwestern University,Xi′an 710127,China;Xi′an Jinborui Ecological Technology Co.,Ltd.,Xi′an 710065,China;Mianxian Rural Energy Station,Hanzhong 724200,China)

机构地区：[1]西北大学城市与环境学院,西安710127 [2]西安金博瑞生态科技有限公司,西安710065 [3]汉中市勉县农村能源工作站,陕西汉中724200

出　　处：《农业环境科学学报》2022年第2期346-356,共11页Journal of Agro-Environment Science

基　　金：国家重点研发计划重点专项(2019YFD1002404);陕西省重点研发计划项目(2019NY-200,2020ZDLNY06-06,2020ZDLNY07-10);西安市科技计划项目(2019-GXYD18.9,20193057YF045NS045)。

摘　　要：以废白土为原料,分别在300、500℃和700℃条件下限氧热解制备废白土炭复合材料A&C300、A&C500、A&C700,采用H_(3)PO_(4)活化法对复合材料进行改性制备HA&C300、HA&C500和HA&C700,分析改性前后复合材料对恩诺沙星(ENR)的吸附效应,筛选出吸附效果最佳的材料;采用比表面积测试仪、扫描电镜-能谱分析、透射电镜、X射线光电子能谱仪及傅里叶红外光谱仪对筛选出的材料进行结构表征;研究改性复合材料吸附ENR的影响因素(ENR浓度、复合材料投加浓度和溶液pH),并结合吸附动力学、等温吸附模型和吸附热力学探究其对ENR的吸附作用机制。结果表明:未改性的废白土炭复合材料对ENR吸附效果较差,而采用H_(3)PO_(4)改性后的复合材料对ENR吸附效果均有所提升,其中HA&C300吸附效果最佳;与A&C300相比,HA&C300表面官能团丰富度和含氧官能团数量增加,疏水性增强,比表面积和总孔容分别为45.72 m^(2)·g^(-1)和0.10 cm^(3)·g^(-1),分别是A&C300的1.54倍和1.59倍;当ENR初始浓度为10 mg·L^(-1)时,HA&C300对ENR吸附的最佳参数为投加浓度0.5 g·L^(-1)、pH 6,此时去除率最高达到92.34%,是A&C300去除率的2倍,最大吸附量达66.79 mg·g^(-1)。HA&C300对ENR的吸附过程符合拟二级动力学方程和Freundlich模型,吸附过程主要受控于化学吸附,为自发的吸热反应,吸附机制包括氢键、π-πEDA、疏水作用和孔径填充。A&C300,A&C500,and A&C700 were prepared by pyrolyzing spent bleaching earth at 300,500℃,and 700℃,respectively,under limited oxygen and then modified by H_(3)PO_(4) activation to prepare HA&C300,HA&C500,and HA&C700.Subsequently,the adsorption effects of enrofloxacin(ENR)by unmodified and modified spent bleaching earth carbon composites were compared,and the material with the highest adsorption ability was selected.The selected material was characterized using a surface area analyzer(BET),scanning electron microscopy-energy spectroscopy(SEM-EDS),transmission electron microscopy(TEM),X-ray photoelectron spectroscopy(XPS),and Fourier transform infrared spectroscopy(FTIR).The determining factors(the initial concentration of ENR,the concentration of the adsorbent,and the pH)on the adsorption effects were investigated.The adsorption mechanisms of ENR by modified spent bleaching earth carbon composites were discussed based on adsorption kinetics,isothermal adsorption model,and adsorption thermodynamics.The data showed that the adsorption of ENR by unmodified spent bleaching earth carbon composites was poor while H_(3)PO_(4) modified composites showed better adsorption effects,among which HA&C300 had the highest adsorption ability.When compared with A&C300,HA&C300 had more functional groups containing oxygen and a stronger hydrophobicity.The surface area and total pore volume were 45.72 m^(2)·g^(-1) and 0.10 cm^(3)·g^(-1),respectively,which were approximately 1.54 times and 1.59 times as large as that of A&C300.When the initial concentration of ENR was 10 mg·L^(-1) and the concentration of HA&C300 was 0.5 g·L^(-1),and pH=6(i.e.,optimal adsorption conditions)the rate of adsorption of ENR by HA&C300 was 92.34%,which was approximately double that of A&C300.Adsorption models and thermodynamic analysis indicated that the pseudo-second-order kinetic model and Freundlich model could describe the adsorption process of ENR onto HA&C300 better,and its maximum adsorption capacity was 66.79 mg·g^(-1).The adsorption process wa

关 键 词：恩诺沙星 改性废白土 废白土炭复合材料 吸附作用机制 

分 类 号：TQ424[化学工程] X703[环境科学与工程—环境工程]