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Preparation of Expanded Chitin Foams and their Use in the Removal of Aqueous Copper
Published on: February 27, 2021
Modification of chitosan with carboxyl-functionalized ionic liquid for anion adsorption
Yanqi Wei1, Wei Huang, Yuan Zhou
1Jiangsu Key Laboratory of Radiation Medicine and Protection, School of Radiation Medicine and Protection, and School for Radiological and Interdisciplinary Sciences (RAD-X), Medical College of Soochow University, Suzhou 215123, PR China; Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, PR China.
Abstract:
We report a novel chitosan derivative, chitosan-ionic liquid (CS-IL) conjugation for anion adsorption. Specifically, CS-IL conjugation was synthesized through the reaction of amino groups of chitosan with carboxylic groups of 1-carboxybutyl-3-methylimidazolium chloride. Due to the amphiphilic structure, CS-IL conjugation could self-assemble into nanoparticles in distilled water. This novel chitosan derivative revealed good anion adsorption performance, and the adsorption capacity of Cr2O7(2-) and PF6(-) was 0.422 mmol/g and 0.840 mmol/g, respectively. The adsorption of Cr2O7(2-) and PF6(-) could be improved at low pH, which was ascribed to the adsorption of protonated NH2 on chitosan. Importantly, the chitosan derivative would aggregate in the water after the adsorption and could be easily separated. The properties enable CS-IL conjugation to be used as a novel anion adsorbent for wastewater treatment.
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