Preparation And Application Of Chitosan Derivatives In Water Treatment

I In this subject by microwave methods,using chitosan as raw materials to makecarboxymethyl chitosan(CMC). In order to ameliorate the water solubility of CMC,thesodium bentonite was studied, and the sodium bentonite was loaded with the CMCunder the best conditions. The composite adsorbents of CMC loaded with sodiumbentonite(BCMC) and chitosan loaded with sodium bentonite(BCTS) were made. Thesurface structrue and composite mechanism of the adsorbents were analyzed by SEMand FTIR. And the adsorption behavior of the CMC、BCMC and BCTS toward acidscarlet and Cu2+were studied. The factors that might influent the absorption behavior ofthe adsorbents were investigated. The adsorption course of the adsorbents were studiedrespectively by Langmuir and Freundlich models, and Pseudo level and Pseudosecondary dynamics models. Finally, the solution was treated respectively by these threeadsorbents, and the properties of three adsorbents were compared.The results showed that:(1)The optimum reaction condition of CMC were as follows:chitosan1g;30%NaOH6ml; chloroacetic acid1.4g; reaction tempreture50℃; the time20min.(2) The optimum reaction condition of BCMC were as follows: the CMC underoptimal conditions and sodium bentonite mass ratio is1:30, the water bath temperatureunder stirring is65℃, and the time is4h;(3) The FTIR and SEM graph demonstratedthat:the infrared spectrum of CMC had carboxymethyl peak and had porousstructure;the infrared spectrum of BCMC and BCTS had peaks of bentonite,and CMCand chitosan were intercalated in bentonite interlayers successfully;BCMC and BCTShad irregular flakes layered structure;(4) Thermodynamic data showed that theadsorption of CMC、BCMC and BCTS toward acid scarlet fit Freundlich model.Dynamics data showed that the process fit the secondary dynamics;(5) Thermodynamicdata showed that the adsorption of CMC、BCMC and BCTS toward Cu2+fit Freundlichmodel. Dynamics data showed that the process fit the secondary dynamics;(6)CMC、BCMC and BCTS.were used to treat the mixed solution,and the these absorbents hadgood regeneration in the process of five reuse times.