Microwave preparation and adsorption properties of EDTA-modified cross-linked chitosan

• Published in: Journal of applied polymer science 2010-01, Vol.115 (1), p.514-519
• Main Authors: Ge, Huacai, Huang, Shiying
• Format: Article
• Language: English
• Subjects: Adsorbents; Adsorption; Applied sciences; chemical modification; Chitosan; Crosslinking; EDTA; Exact sciences and technology; Metal ions; microwave irradiation; Microwaves; Natural polymers; Physicochemistry of polymers; Reproduction; Starch and polysaccharides; Thermogravimetric analysis
• ISSN: 0021-8995; 1097-4628; 1097-4628
• DOI: 10.1002/app.30843

A novel chitosan-based adsorbent (CCTE) was synthesized by the reaction between epichlorohydrin O-cross-linked chitosan and EDTA dianhydride under microwave irradiation (MW). The chemical structure of this new polymer was characterized by infrared spectra analysis, thermogravimetric analysis, and X-ray diffraction analysis. The results were in agreement with the expectations. The static adsorption properties of the polymer for Pb²⁺, Cu²⁺, Cd²⁺, Ni²⁺, and Co²⁺ were investigated. Experimental results demonstrated that the CCTE had higher adsorption capacity for the same metal ion than the parent chitosan and cross-linked chitosan. In particular, the adsorption capacities for Pb²⁺ and Cd²⁺ were 1.28 mmol/g and 1.29 mmol/g, respectively, in contrast to only 0.372 mmol/g for Pb²⁺ and 0.503 mmol/g for Cd²⁺ on chitosan. Kinetic experiments indicated that the adsorption of CCTE for the above metal ions achieved the equilibrium within 4 h. The desorption efficiencies of the metal ions on CCTE were over 93%. Therefore, CCTE is an effective adsorbent for the removal and recovery of heavy metal ions from industrial waste solutions.