Two kinds of novel chitosan-crown ether resins, Schiff base type chitosan-benzo-15-crown-5 (CTS -B15) and chitosan-benzo-18-crown-6 (CTS -B18), were synthesized through the reaction between -NH2 in chitosan and -C...Two kinds of novel chitosan-crown ether resins, Schiff base type chitosan-benzo-15-crown-5 (CTS -B15) and chitosan-benzo-18-crown-6 (CTS -B18), were synthesized through the reaction between -NH2 in chitosan and -CHO in 4′-formyl benzo-crown ethers. Their structures were characterized by elemental analysis and FT-IR spectra analysis. The elemental analysis results show that the mass fractions of nitrogen in CTS -B15 and CTS -B18 are much lower than those of chitosan. The results of FT-IR spectra of CTS -B15 and CTS -B18 reveal that there exist characteristic peak of C=N, N-H and Ar, and characteristic peak of pyr anoside in the chain of chitosan-crown ether resins, showing that the structures of chitosan-crown ethers are as expected. The adsorption properties of CTS -B15 and CTS -B18 for Pd 2+ , Cu 2+ and Hg 2+ were studied and the experimental results show that these adsorbents have both good adsorption characterization and especially high particular adsorption selectivity for Pd 2+ when Cu 2+ and Hg 2+ are in coexistence, and the coefficients of selectivity of CTS -B15 and CTS -B18 for metal ions are K Pd 2+ /Cu 2+ = 7.56, K Pd 2+ /Hg 2+ = 68.00, K Cu 2+ /Hg 2+ = 9.00 and K Pd 2+ /Cu 2+ =6.00, K Pd 2+ /Hg 2+ =19.00, K Cu 2+ /Hg 2+ =3.00, respectively.展开更多
文摘Two kinds of novel chitosan-crown ether resins, Schiff base type chitosan-benzo-15-crown-5 (CTS -B15) and chitosan-benzo-18-crown-6 (CTS -B18), were synthesized through the reaction between -NH2 in chitosan and -CHO in 4′-formyl benzo-crown ethers. Their structures were characterized by elemental analysis and FT-IR spectra analysis. The elemental analysis results show that the mass fractions of nitrogen in CTS -B15 and CTS -B18 are much lower than those of chitosan. The results of FT-IR spectra of CTS -B15 and CTS -B18 reveal that there exist characteristic peak of C=N, N-H and Ar, and characteristic peak of pyr anoside in the chain of chitosan-crown ether resins, showing that the structures of chitosan-crown ethers are as expected. The adsorption properties of CTS -B15 and CTS -B18 for Pd 2+ , Cu 2+ and Hg 2+ were studied and the experimental results show that these adsorbents have both good adsorption characterization and especially high particular adsorption selectivity for Pd 2+ when Cu 2+ and Hg 2+ are in coexistence, and the coefficients of selectivity of CTS -B15 and CTS -B18 for metal ions are K Pd 2+ /Cu 2+ = 7.56, K Pd 2+ /Hg 2+ = 68.00, K Cu 2+ /Hg 2+ = 9.00 and K Pd 2+ /Cu 2+ =6.00, K Pd 2+ /Hg 2+ =19.00, K Cu 2+ /Hg 2+ =3.00, respectively.