乙酸铁热分解制备磁性纳米氧化铁及对砷的吸附性能  

Preparation of magnetic nano iron oxide by thermal decomposition of ferric acetate and its adsorption performance for arsenic

作　　者：陈瑶姬 宋可鑫 程微[2,3] 吴峰 李进军[2] CHEN Yaoji;SONG Kexin;CHENG Wei;WU Feng;LI Jinjun(Zhejiang Tiandi Environmental Protection Technology Co.,LTD,Hangzhou,311199,China;College of Resources and Environmental Science,Wuhan University,Wuhan,430079,China;College of Resources and Environment,South-Central Minzu University,Wuhan,430074,China)

机构地区：[1]浙江天地环保科技有限公司,杭州311199 [2]武汉大学资源与环境科学学院,武汉430079 [3]中南民族大学资源与环境学院,武汉430074

出　　处：《环境化学》2024年第12期4303-4311,共9页Environmental Chemistry

基　　金：国家自然科学基金(22006165);中央高校基本科研业务费专项资金(CZQ21012)资助.

摘　　要：磁性纳米氧化铁可以高效吸附去除水体中的砷(As),且可通过外加磁场进行分离,但是材料的制备过程一般较复杂.本研究通过简单的乙酸铁热分解法制备了磁性纳米氧化铁,对其进行了表征,并通过批次吸附实验探究了其对As的吸附性能.在氮气氛围中250℃热分解乙酸铁,得到的纳米颗粒粒径约10—12 nm,材料的BET比表面积约90 m^(2)∙g^(−1),主要孔径分布为10—50 nm,为颗粒堆积孔结构.材料在pH 3—9范围内都能高效去除水体中的As,其中在pH 7下的效果最好.吸附等温线符合Langmuir模型,最大吸附量约30 mg∙g^(−1).吸附动力学符合准二级模型,吸附机制为表面化学配位形成内层络合物,离子强度对吸附没有影响.地下水中的常见共存离子对As的吸附没有显著影响.乙酸铁热分解法可作为制备磁性纳米铁基除砷吸附剂的低成本方法.Magnetic iron oxide nanoparticles can efficiently adsorb and remove arsenic from water,and can be separated by an external magnetic field.However,the preparation process of the material is generally complicated.In this study,magnetic iron oxide nanoparticles were prepared using a simple thermal decomposition method,and characterized with different techniques,and then their adsorption performance for As were investigated.The study showed that ferric acetate thermal decomposition at 250℃ under a nitrogen atmosphere produced nanoparticles with a particle size of about 10—12 nm.The BET specific surface area of the material is approximately 90 m^(2)∙g^(−1),with a predominant pore size distribution of 10—50 nm,and possessing a particle aggregate pore structure.The synthesized adsorbents can efficiently remove As from water in the pH range of 3—9,with the best performance achieved at pH 7.The adsorption isotherm fits the Langmuir model,with a maximum adsorption capacity of approximately 30 mg∙g^(−1).The adsorption kinetics follow the pseudo-second order model,and the adsorption mechanism involves surface chemical coordination to form an innersphere complex,which is not affected by ionic strength.The common co-existing ions in groundwater have no significant effects on As removal.The ferric acetate thermal decomposition method can serve as a low-cost method for preparing magnetic iron-based arsenic adsorbents.

关 键 词：砷 纳米氧化铁 磁性吸附剂 水质净化 吸附. 

分 类 号：X-1[环境科学与工程] O6[理学—化学]