朽木纤维素炭/δ-MnO2复合材料的制备及对As(III)的吸附研究  

A Study on Preparation of Rotten Tree Cellulose-derived Carbon/δ-MnO2 Composite and Its Adsorption of As(Ⅲ)

作　　者：杨和平 毛舒蕾 葛雪倩 YANG He-ping;MAO Shu-lei;GE Xue-qian(School of Chemical Engineering and Modern Materials,Shaanxi Key Laboratory of Comprehensive Utilization of Tailings Resources,Shangluo University,Shangluo 726000,Shaanxi)

机构地区：[1]商洛学院化学工程与现代材料学院/陕西省尾矿资源综合利用重点实验室,陕西商洛726000

出　　处：《商洛学院学报》2025年第2期52-59,共8页Journal of Shangluo University

基　　金：国家级大学生创新创业训练计划项目(202311396007)。

摘　　要：采用氧化和吸附两种方式去除水中有害元素砷,通过δ-MnO_(2)与朽木纤维素炭相结合,在吸附过程中将有毒性的As(Ⅲ)氧化为低毒性的As(Ⅴ),降低砷对环境的危害。以朽木纤维素作为碳源,KMnO_(4)作为锰源,在水热条件下制备了朽木纤维素炭/δ-MnO_(2)复合材料(RWCC/δ-MnO_(2)),并将其作为吸附剂,探究了pH、吸附剂用量、吸附温度、吸附时间等对As(Ⅲ)的吸附影响。借助准一级、准二级动力学模型及Langmuir和Freundlich两种等温吸附模型研究了朽木纤维素炭/δ-MnO_(2)复合材料对As(Ⅲ)的吸附机理。结果表明,在RWCC/δ-MnO_(2)复合材料中δ-MnO_(2)的氧化作用下,实现了有毒性的As(Ⅲ)向低毒性的As(Ⅴ)的转化。在25℃,pH=4,吸附剂用量为70 mg时,朽木纤维素炭/δ-MnO_(2)复合材料对As(Ⅲ)的最大吸附量为4.28 mg/g,最大去除率为75.85%,在20 min达到吸附平衡,说明吸附过程相对较快。A combined approach of oxidation and adsorption was employed to effectively remove arsenic from water.Specifically,the highly toxic As(Ⅲ)was oxidized to the less toxic As(Ⅴ)during the adsorption process.The rotten tree cellulose-derived carbon/δ-MnO_(2) composite(RWCC/δ-MnO_(2))was prepared under hydrothermal conditions with RWCC as carbon source and KMnO_(4) as manganese source.The influence of various factors,including pH,adsorbent dosage,adsorption temperature,and adsorption time,on the removal of As(Ⅲ)by the RWCC/δ-MnO_(2) composite was systematically investigated.The adsorption mechanism of RWCC/δ-MnO_(2) composites for As(Ⅲ)was studied by means of quasi-first-order and quasisecond-order kinetic models,as well as Langmuir and Freundlich isothermal adsorption models.The results show that the conversion of toxic As(Ⅲ)to less toxic As(Ⅴ)is achieved under the oxidation ofδ-MnO_(2) in RWCC/δ-MnO_(2) composite.At 25℃,pH=4 and the dosage of adsorbent 70 mg,the RWCC/δ-MnO_(2) composite exhibited a maximum adsorption capacity for As(Ⅲ)of 4.28 mg/g,with a maximum removal rate of 75.85%.The adsorption equilibrium was reached within 20 minutes,indicating a relatively fast adsorption process.

关 键 词：生物质炭 朽木 MnO_(2) 砷吸附 

分 类 号：TB33[一般工业技术—材料科学与工程]