摘要
硝酸盐是水体中重要的污染物之一.本文以新型盐酸叔胺大孔树脂(TAHMR)为吸附剂,采用扫描电镜、红外光谱(FTIR)、X射线光电子能谱(XPS)和Zeta电位等手段表征了其结构.系统研究了TAHMR树脂投加量、溶液pH、离子强度和共存组分等因素对水中NO_(3)^(-)静态吸附性能的影响.结果表明,TAHMR在较宽的pH4.0-10.0范围内具有良好的吸附性能,当pH为6.0时吸附量最大.吸附平衡时间在25 min内,NO_(3)^(-)在TAHMR上吸附过程符合拟二级动力学吸附模型,Langmuir等温吸附模型可以很好地描述TAHMR对溶液中NO_(3)^(-)的吸附过程,最大吸附量为2.94 mmol·g^(-1)(pH=6.0和25℃).吸附热力学结果表明,在TAHMR上的吸附是一个自发的物理吸附过程,说明吸附过程是自发吸热过程,属于物理吸附.经FTIR和XPS表征,TAHMR上的叔胺基团参与NO_(3)^(-)吸附,并存在离子交换作用力.脱附再生实验发现,1.0mmol·L^(-1)NaOH溶液脱附效果优于其他脱附液.具有较强的再生能力,经5次循环后其对NO_(3)^(-)的去除率没有明显下降.因此,TAHMR作为一种经济高效的吸附剂,可为树脂吸附法去除饮用水的NO_(3)^(-)提供新的手段.
Nitrate anion(NO_(3)^(-))is one of the main important pollutants in water.A novel type of Tertiary amine hydrochloride macroporous resin(TAHMR)was used as adsorbent to remove nitrate anion from aqueous solutions.The resins were characterized by scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),and Zeta potential.The adsorptive removal of NO_(3)^(-) from aqueous solution was then investigated as a function of TAHMR resin dosage,solution pH,ionic strength,and co-existing components.The results showed that TAHMR resin exhibits the excellent performance in the pH range of 4.0−10.0 and the maximum adsorption capacity of at pH 6.0.The adsorption equilibrium of TAHMR on NO_(3)^(-) reached at 25 min,and the adsorption kinetics of NO_(3)^(-) on TAHMR was best described by the pseudo second-order kinetic model.The adsorption isotherm data fits well the Langmuir model with the calculated maximum monolayer adsorption capacity was 2.94 mmol·g^(-1) at pH 6.0 and 25℃.Thermodynamic calculations show that the adsorption of NO_(3)^(-) was a spontaneous and endothermic process.The combined results of FTIR and XPS further showed that the amine oxide structure on TAHMR resins involved in the adsorption of NO_(3)^(-).Desorption experiments showed that the TAHMR resin could be efficiently regenerated by 1.0 mmol·L^(-1) NaOH and showed no obvious decrease in adsorption capacity through five regeneration recycles.Therefore,TAHMR,as a cost-effective adsorbent,can provide a new means for the adsorptive removal of NO_(3)^(-) in drinking water.
作者
张云鹏
张丹丹
刁开盛
董慧峪
李梦凯
刘敏
刘绍刚
ZHANG Yunpeng;ZHANG Dandan;DIAO Kaisheng;DONG Huiyu;LI Mengkai;LIU Min;LIU Shaogang(Key Laboratory of Chemistry and Engineering of Forest Products,State Ethnic Affairs Commission,Guangxi Key Laboratory of Chemistry and Engineering of Forest Products,Guangxi Collaborative Innovation Center for Chemistry and Engineering of Forest Products,School of Chemistry and Chemical Engineering,Guangxi Minzu University,Nanning,530008,China;Key Laboratory of Drinking Water Science and Technology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing,100085,China)
出处
《环境化学》
CAS
CSCD
北大核心
2023年第11期3892-3903,共12页
Environmental Chemistry
基金
国家自然科学基金(21976040,22166007,22166008)
广西高等学校高水平创新团队及卓越学者计划(桂教人[2020]6号)
广西区研究生教育创新计划项目(YCSW2022244,YCBZ2023114)资助.
关键词
盐酸叔胺离子交换树脂
硝酸根
吸附动力学
竞争吸附
吸附机制
tertiary amine hydrochloride macroporous resin
nitrate anion
adsorption kinetics
competitive adsorption
adsorption mechanism
作者简介
通信联系人:刘敏,E-mail:20159056@gxmzu.edu.cn;通信联系人:刘绍刚,E-mail:liushaogang2005@163.com。
