新型交联壳聚糖树脂的制备及其对苯甲酸的吸附行为研究

Studies on Preparation of the Novel Crosslinked Chitosan Resin and Adsorption of Benzoic Acid

以壳聚糖为原料 ,甲醛为预交联剂 ,环氧氯丙烷为交联剂 ,通过反相悬浮交联法制备出新型壳聚糖树脂 ,并用红外光谱和扫描电镜对其结构进行表征 .测定了不同温度下新制备树脂自水中吸附苯甲酸的等温线 ,计算了吸附过程的热力学参数 .并用Freundlich方程对实验数据进行拟合 ,发现该方程适用于所研究的吸附体系 .体系的热力学与吸附机理密切相关 ,当苯甲酸浓度较低时 ,吸附为放热过程 ,体系熵减少 ,降温有利于吸附 ;当苯甲酸浓度较高时 ,吸附为吸热过程 ,体系熵增加 ,升温有利于吸附 .

With chitosan as the raw material, a novel resin was prepared through inverse suspension crosslinking by formaldehyde and epichlorohydrin. The structure of the resin was characterized by Fourier transform IR and Scanning Electron Micrograph. The adsorption isotherms of benzoic acid from water onto the novel resin were determined at different temperatures, and the thermodynamic parameters in adsorption process were calculated. The experimental results were fitted with Freundlich equations well. The thermodynamics of the systems was related closely to the adsorption mechanisms. When the concentration of benzoic acid was relatively low, the adsorption was an exothermal process with the system entropy decreasing, and the decrease of temperature did benefit the process. When the concentration of benzoic acid was relatively high, the adsorption was an endothermal process with the system entropy increasing, and the increase of temperature did benefit the process.