The Preparation, Characterization And Dye Adsorbing Properties Of Chitosan Film Coated Quartz Sand

Chitosan, a natural polymer, has been widely used in water treatment with its properties ofwide variety of sources, good biocompatibility, easy film-forming ability, easy biodegradability,and so on. However, chitosan is easily dissolved in acid conditions, which limits its applicationin the industry. Chitosan has been used to preper crosslinked chitosan film and crosslinkedporous chitosan film. In addition, it has successfully coated onto quartz sand. The structre of theadsorbents have been characterized by FTIR, SEM, and XRD, and applied to adsorb dye fromaqueous solution.Crosslinking chitosan film has been prepared by using glutaraldehyde as crosslinkingagent. The better mechanical property happens when the dosage of glutaraldehyde is0.5ml. Theresults indicate this cross-linked chitosan film shows good adsorption performance towards sixdyes. The adsorption kinetics isotherms showed that the adsorption processes were better fittedby pseudo-second order equation.The crosslinked porous chitosan films were made by the step of pre-crosslinking, formporous and crosslinking, then, layer and porous microstructure were formed. The film couldsuccessfully remove96%of congo red under appropriate conditions. Compared with thecrosslinked films, the adsorption capacity of crosslinked porous chitosan films increased6.23%.The adsorption kinetics and equilibrium isotherms showed that the adsorption processes werebetter fitted by pseudo-second order equation and Langmuir equation, respectively. Adsorptionthermodynamics indicate the spontaneous nature and endothermic of the adsorption process.chitosan coated quartz sand can adsorb Congo red quickly and effectively, with theadsorption rate of96%. The adsorption processes were better fitted by pseudo-second orderequation and Langmuir equation, respectively. Adsorption thermodynamics indicate thespontaneous nature and exothermic of the adsorption process. The dynamic tests showed thatusing chitosan coated quartz sand as a filter, the micro-filter filtration system could operate11hefficiently and stably.