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In this paper, the characteristics of chitosan and bentonite , extraction of the metal ion template bentonite crosslinked chitosan and chitosan composites were investigated for their lead, neodymium and other heavy metal ions adsorption , and the results are as follows . Lead ion template Crosslinked Chitosan optimal synthesis conditions : chitosan mass ratio of 1:0.094 lead ions , complexation reactions 7h, 25% aqueous glutaraldehyde cross-linking agent dosage 6mL, crosslinking time 16h. Neodymium ion template Crosslinked Chitosan optimal synthesis conditions : chitosan mass ratio of 1:0.10 with neodymium ions , complexation reactions 7h, 25% aqueous glutaraldehyde cross-linking agent dosage 6mL, crosslinking time was 16h. Chitosan bentonite composite synthesis conditions : 95% degree of deacetylation of chitosan and bentonite mass ratio of 1:25 . Metal ion template overcome chitosan crosslinked polymer will be dissolved under acidic conditions in the disadvantage , when the pH is near neutral , the module Crosslinked lead , neodymium, the maximum adsorption capacity were 58.23mg / g and 41.09mg / g. Chitosan bentonite composite lead when pH = 7 , neodymium ion adsorption capacity is about 76.75mg / g, 91.71mg / g. Template crosslinked chitosan lead , neodymium ions adsorbed at 18h and 2h , respectively, to achieve balance, and chitosan bentonite composite materials for lead , neodymium ions adsorbed 2h and 30min respectively, in which equilibrium is reached. Two kinds of chitosan composite adsorbent for lead , neodymium ions are the Freundlich adsorption isotherm , indicated that the adsorption is more heterogeneous molecular layer adsorption dominated ; and both meet Lagergren two adsorption kinetic models . Infrared analysis showed that the template partially crosslinked chitosan reactive amino group has coordinated with the role of metal ions , hydroxyl and amino groups with glutaraldehyde cross-linking reaction occurs . X-ray diffraction analysis showed that chitosan composite bentonite d001 value increased by only 0.04nm, description chitosan layer spacing increases after the bentonite is not obvious . Template Crosslinked Chitosan and chitosan bentonite composite materials have good adsorption properties , which not only chitosan composite bentonite adsorption speed , high adsorption capacity , and the synthesis process is simple, low cost of production .
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