Synthesis, characterization, and adsorption properties of chitosan azacrown ethers bearing hydroxyl group

Two new chitosan azacrown ethers bearing hydroxyl groups (CTS-DH and CTS-DO) were synthesized by the reaction of 3-hydroxyl-1,5-diaza-cycloheptane and 3-hydroxyl-1,5-diaza-cyclooctane with epoxy-activated chitosan. Their structures were characterized by elemental analysis, infrared spectra analysis, and X-ray diffraction analysis. The adsorption and selectivity properties of the hydroxyl azacrown ethers chitosan derivatives for Ag+, Cr3+, Cd2+, and Pb2+ were also investigated. The experimental results showed that the two novel chitosan azacrown ethers have good adsorption capacity for Ag+, and also showed that the grafted chitosan azacrown ethers have high selectivity for the adsorption of Ag+ in the presence of Pb2+ and Cd2+. The selectivity coefficients of CTS-DH and CTS-DO were K = 21, K = 42, K = 20.5, K = 41, respectively. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1793–1798, 2001