十六烷基三甲基溴化铵改性沸石对腐殖酸的吸附性能研究  

Research on adsorption properities of cetyltrimethylammonium bromide modified zeolite on humic acid

作　　者：张国珍[1] 高小波[1] 武福平[1] 杨光[1] 巩师俞[1] 

机构地区：[1]兰州交通大学环境与市政工程学院,甘肃兰州730070

出　　处：《环境污染与防治》2016年第5期12-17,共6页Environmental Pollution & Control

基　　金：国家自然科学基金资助项目(No.51068014;No.51468033);长江学者和创新团队发展计划资助项目(No.IRT0966)

摘　　要：以十六烷基三甲基溴化铵(CTAB)为改性剂,制备了CTAB改性沸石,并用于对腐殖酸的吸附性能研究。考察了pH、吸附时间及腐殖酸初始浓度对CTAB改性沸石吸附腐殖酸的影响,采用吸附等温方程和反应动力学方程进行拟合分析,并利用扫描电子显微镜(SEM)、X射线光电子能谱仪(XPS)、傅立叶转换红外光谱分析仪(FTIR)对沸石改性前后进行结构表征。结果表明,在温度为25℃、转速为200r/min的条件下,选择pH为7.0、腐殖酸初始质量浓度为10mg/L、吸附时间为180min,此时CTAB改性沸石对腐殖酸的平衡吸附容量为0.16mg/g。相比Freundlich吸附等温方程(R2=0.967),CTAB改性沸石对腐殖酸的吸附更符合Langmuir吸附等温方程(R2=0.998),吸附机制为单分子层吸附。准一级反应动力学方程和准二级反应动力学方程均可以描述CTAB改性沸石对腐殖酸的吸附(R2=0.978)。吸附实验后的CTAB改性沸石上出现了甲基、亚甲基、羟基与羰基伸缩振动吸收峰,说明沸石已负载了CTAB,且腐殖酸已被CTAB改性沸石吸附。Cetyltrimethylammonium bromide （CTAB） was chosen as modifier to prepare CTAB modified zeo- lite. Adsorption properties of CTAB modified zeolite on humic acid were studied. Effects of pH,adsorption time and humic acid initial concentration on the humic acid adsorption by CTAB modified zeolite were investigated. Adsorption isotherm equations and reaction kinetic equations were used to fit the adsorption process. Scanning electron micro- scope （SEM）, X-ray photoelectron spectroscopy （XPS） and Fourier transform infrared spectroscopy （FTIR） were used to characterize the zeolite before and after CTAB modification. The results showed that the adsorption capacity reached 0.16 mg/g on optimized conditions that pH was 7.0,humic acid initial mass concentration was 10 mg/L and adsorption time was 180 min,when temperature was 25℃ and shaking speed was 200 r/min. The adsorption process of CTAB modified zeolite on humid acid was more consistent with the Langmuir adsorption isotherm equation （Rz = 0.998） than Freundlich adsorption isotherm equation （R 2 = 0.967）, so the adsorption mechanism should be single mo- lecular layer adsorption. Both pseudo first-order reaction kinetic equation and pseudo second-order reaction kinetic equation could well describe the humic acid adsorption by CTAB modified zeolite （R2 = 0.978）. Stretching vibration adsorption peaks of methyl, methylene, hydroxy and carbonyl appeared after adsorption, indicating that CTAB had been loaded onto zeolite and humic acid had been adsorbed by CTAB modified zeolite.

关 键 词：十六烷基三甲基溴化铵 改性沸石 吸附 腐殖酸 

分 类 号：X703[环境科学与工程—环境工程] O647.3[理学—物理化学]