荔枝果皮的胺基改性及对水中Cr(Ⅵ)的吸附去除特性  

Amino-modified lychee pericarp and its adsorption property for Cr(Ⅵ)removal

作　　者：马金珍 王芷薇 廖翊芳 李平 Ma Jinzhen;Wang Zhiwei;Liao Yifang;Li Ping(Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters,School of Environment and Energy,South China University of Technology,Guangzhou 510006;Key Laboratory of Pollution Control and Ecological Restoration of Guangdong Higher Education Institutes,South China University of Technology,Guangzhou 510006)

机构地区：[1]华南理工大学环境与能源学院,工业聚集区污染控制与生态修复教育部重点实验室,广州510006 [2]华南理工大学环境与能源学院,污染控制与生态修复广东省普通高等学校重点实验室,广州510006

出　　处：《化工新型材料》2022年第5期274-280,285,共8页New Chemical Materials

基　　金：国家自然科学基金(41977114);广东省基础与应用基础研究基金(2020A1515011113);广州市科技计划项目(202002030455)。

摘　　要：采用热化学改性法分别在30℃和65℃下制备了聚乙烯亚胺(PEI)改性荔枝果皮(MLP30和MLP65),用于去除废水中的Cr(Ⅵ)。结果表明,PEI上的胺基和亚胺基通过与果皮含氧官能团反应成功接枝到天然荔枝果皮吸附剂(LP)表面,增强了对废水中Cr(Ⅵ)的吸附能力。MLP对Cr(Ⅵ)的吸附符合Elovich动力学和Langmuir吸附等温模型,pH为4.0时,MLP30和MLP65对Cr(Ⅵ)的理论吸附容量分别为122.95mg/g和156.82mg/g,相较于LP(66.41mg/g)分别提高了85.1%和136.1%。MLP吸附Cr(Ⅵ)的主要机理包括静电吸引相互作用、氧化还原和表面络合。在酸性和弱酸性条件下MLP65都能有效去除水中的Cr(Ⅵ),且循环利用性能良好,是一种具有潜在利用价值的生物质吸附剂。研究结果可为废弃荔枝果皮的资源化与Cr(Ⅵ)污染控制提供理论依据和技术参考。Polyethylenimine(PEI)modified lychee pericarp(MLP30 and MLP65)were prepared by thermochemical modification method at 30℃and 65℃,then used to remove Cr(Ⅵ)from wastewater.The Cr(Ⅵ)adsorption capacity was enhanced due to the amines and imines on PEI successfully grafted to the surface of LP by reacting with the oxygen-containing functional groups.The adsorption of Cr(Ⅵ)by MLP30 and MLP65 agreed well with Elovich kinetic model and Langmuir isotherm model.The theoretical adsorption capacity of MLP30 and MLP65 for Cr(Ⅵ)was 122.95 mg/g and 156.82 mg/g respectively which increased by 85.1%and 136.1%when compared to LP(66.41 mg/g)at pH 4.0.The mechanisms of Cr(Ⅵ)adsorption mainly included electrostatic attraction,oxidation-reduction reaction and surface complexation.MLP65 had good adsorption capacity under acidic and weak acidic conditions and good recycling performance,so it could be regarded an adsorbent with great potential utilization value.The research can provide theoretical foundation and technical reference for the resource utilization of pericarp waste and Cr(Ⅵ)pollution control in wastewater.

关 键 词：吸附 荔枝果皮 聚乙烯亚胺 表面改性 Cr(Ⅵ) 

分 类 号：TQ424[化学工程] X52[环境科学与工程—环境工程]