High phosphate removal using La(OH)3 loaded chitosan based composites and mechanistic study  

作　　者：Shaopeng Zhang Yi Zhang Jie Ding Zepeng Zhang Chao Gao Muslim Halimi Hary Demey Zhen Yang Weiben Yang 

机构地区：[1]School of Chemistry and Materials Science,Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control,Nanjing Normal University,Nanjing 210023,China [2]Department of Chemical and Environmental Engineering,Anyang Institute of Technology,Anyang 455000,China [3]Department of Chemical Engineering,Universitat Politècnica de Catalunya,Barcelona 08028,Spain

出　　处：《Journal of Environmental Sciences》2021年第8期105-115,共11页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.51978341 and 52070100);the Natural Science Foundation of Jiangsu Province of China(No.BK20190087);。

摘　　要：Our present study was to prepare a biomass-supported adsorbents with high adsorptive capacity and high selectivity to prevent the accelerated eutrophication in water body.To this end,different metal hydroxide(La,Zr and Fe)first was successfully loaded on chitosan microspheres.Then the quaternary ammonium group with different content was introduced into the adsorbent by polymerization.By comparison of adsorption properties,chitosanLa(OH)3-quaternary ammonium-20%(CS-La-N-20%)has strong adsorption to phosphate(160 mg/g)by immobilizing nano-sized La(OH)3 within a quaternary-aminated chitosan and it maintain high adsorption in the presence of salt ions.The pH results indicated that the CS-La-N-20%would effectively sequestrate phosphate over a wide pH range between 3 and 7 without significant La3+leaching.What’s more,adsorption capacity on the introduce of positively charged quanternary-aminated groups was significantly higher than that of the unmodified adsorbents at alkaline conditions.The column adsorption capacity reached 1300 bed volumes(BV)when phosphate concentration decreased until 0.5 mg/L at 6 BV/hr.The column adsorption/desorption reveals that no significant capacity loss is observed,indicating excellent stability and repeated use property.Characterizations revealed that phosphate adsorption on CS-La-N-20%through ligand exchange(impregnated nano-La(OH)3)and electrostatic attraction(positively charged quanternary-aminated groups).All the results suggested that CS-La-N-20%can serve as a promising adsorbent for preferable phosphate removal in realistic application.

关 键 词：PHOSPHATE Chitosan-nanocomposite Metal hydroxide Quaternary ammonium 

分 类 号：TQ424[化学工程] TB332[一般工业技术—材料科学与工程] X52[环境科学与工程—环境工程]