Synthesis and adsorption properties for metal ions of crosslinked chitosan acetate crown ethers

✍ Scribed by Shuying Tan; Yuting Wang; Changhong Peng; Yurong Tang

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 144 KB
• Volume: 71
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19990321)71:12<2069::aid-app17>3.0.co;2-s

✦ Synopsis

Two novel chitosan derivatives-crosslinked chitosan dibenzo-16-c-5 acetate crown ether (CCTS-1) and crosslinked chitosan 3,5-di-tert-butyl dibenzo-14-c-4 diacetate crown ether (CCTS-2)-were synthesized by the reaction of crosslinked chitosan with dibenzo-16-c-5 chloracetate crown ether and 3,5-di-tert-butyl dibenzo-14-c-4 dichloracetate crown ether with the intent of forming polymers that could be used in hazardous waste remediation as toxic metal-binding agents in aqueous environments. Their structures were confirmed with elemental analysis, infrared spectral analysis, and X-ray diffraction analysis. In the infrared spectra of CCTS-1 and CCTS-2, the characteristic peaks of aromatic backbone vibration appeared at 1595 cm Ϫ1 and 1500 cm Ϫ1 ; the intensity of the NOH and OOH stretching vibration in the region of 3150 -3200 cm Ϫ1 decreased greatly. The X-ray diffraction analysis showed that the peak at 2 ϭ 20°decreased greatly in CCTS-1 and CCTS-2. The adsorption and selectivity properties of CCTS-1 and CCTS-2 for Pb 2ϩ , Cu 2ϩ , Cr 3ϩ , and Ni 2ϩ were studied. Experimental results showed that the two crosslinked chitosan derivatives had not only good adsorption capacities for Pb 2ϩ , Cu 2ϩ , but also high selectivity for Pb 2ϩ , Cu 2ϩ in the coexistence of Ni 2ϩ . For aqueous systems containing Pb 2ϩ , Ni 2ϩ , or Cu 2ϩ , Ni 2ϩ , CCTS-1 only adsorbed Pb 2ϩ or Cu 2ϩ . For aqueous systems containing Pb 2ϩ , Cr 2ϩ and Ni 2ϩ , CCTS-2 had high adsorption and selectivity properties for Pb 2ϩ .