摘要
By the Schiff-base condensation of formacyl calix[4]crown（2） with raw chitosan, a novel calix[4]crown- grafted chitosan chelating polymer（3） was conveniently prepared in good yield. The structure of polymer 3 was con- firmed by elemental analysis, infrared（IR） spectrometry and X-ray diffraction（XRD） analysis. The elemental analysis suggests that the grafting degree of calixcrown unit was 22% on the amino groups of chitosan. The morphological characteristic of polymer 3 was studied by scanning electron microscopy（SEM）. Polymer 3 possessed loose porous and smooth morphology of surface. The dyes adsorption abilities of polymer 3 for a series of organic dyes[Orange I（OI）, Neutral red（NR）, Victoria blue B（VB） and Brilliant green（BG）] were studied by solid-liquid adsorption expe- riments. The adsorption percentages increased from 45%-60%（raw chitosan for dyes） to 75%-90%（polymer 3 for dyes）. The highest adsorption percentage reached 89% for VB. The saturated adsorption capacities for OI, NR, VB and BG were as high as 622, 564, 854 and 781 mg/g, respectively. The adsorption abilities kept stable at 70%-90% in the scope of pH=5-9. The adsorption abilities for anionic dye（OI） decreased gradually with the increase of pH and the opposite trend was observed for cationic dyes（NR, BG, VB）. The adsorption percentages were 70%--90% after five times＇ cycles for adsorption.
By the Schiff-base condensation of formacyl calix[4]crown（2） with raw chitosan, a novel calix[4]crown- grafted chitosan chelating polymer（3） was conveniently prepared in good yield. The structure of polymer 3 was con- firmed by elemental analysis, infrared（IR） spectrometry and X-ray diffraction（XRD） analysis. The elemental analysis suggests that the grafting degree of calixcrown unit was 22% on the amino groups of chitosan. The morphological characteristic of polymer 3 was studied by scanning electron microscopy（SEM）. Polymer 3 possessed loose porous and smooth morphology of surface. The dyes adsorption abilities of polymer 3 for a series of organic dyes[Orange I（OI）, Neutral red（NR）, Victoria blue B（VB） and Brilliant green（BG）] were studied by solid-liquid adsorption expe- riments. The adsorption percentages increased from 45%-60%（raw chitosan for dyes） to 75%-90%（polymer 3 for dyes）. The highest adsorption percentage reached 89% for VB. The saturated adsorption capacities for OI, NR, VB and BG were as high as 622, 564, 854 and 781 mg/g, respectively. The adsorption abilities kept stable at 70%-90% in the scope of pH=5-9. The adsorption abilities for anionic dye（OI） decreased gradually with the increase of pH and the opposite trend was observed for cationic dyes（NR, BG, VB）. The adsorption percentages were 70%--90% after five times＇ cycles for adsorption.
基金
Supported by the National Natural Science Foundation of China（No.21406036）, the Natural Science Foundation of Fujian Province of China（No.2014J01034）, the Project of Department of Education of Fujian Province of ChinafNos.JA11044, JA10056, JB 13011） and the Program for Innovative Research Team in Science and Technology in Fuj ian Province University, China.
