壳聚糖改性蒙脱石对蔗糖溶液中酚酸的吸附性能研究

通过共沉淀法制备壳聚糖改性蒙脱石并用于蔗糖溶液中酚酸的吸附。通过SEM、FT-IR、XPS和BET对其进行表征，由表征结果可知:改性过程成功地将壳聚糖负载到蒙脱石表面，制备出壳聚糖改性蒙脱石；改性蒙脱石等电点为7.84，主要通过静电力和胺基吸附蔗糖溶液中的没食子酸。吸附试验结果表明改性后的蒙脱石对没食子酸吸附性能提高，壳聚糖改性蒙脱石对蔗糖溶液中没食子酸吸附的最佳pH为7.0，平衡时间为600 min。壳聚糖改性蒙脱石对没食子酸的吸附过程更加符合Freundlich模型和准二级吸附动力学方程，吸附过程主要为多分子层吸附和化学吸附，饱和吸附量达到58.82 mg/g。壳聚糖改性蒙脱石具有良好的再生性能，且对蔗糖溶液中酚酸吸附效果良好，是一种有前景的糖用澄清剂。

Adsorption of Phenolic Acids from Sucrose Solution by Chitosan Modified Montmorillonite

Chitosan modified montmorillonite was prepared by coprecipitation method and used to adsorb phenolic acids in sucrose solution. It was characterized by SEM, FT-IR, XPS and BET. The results showed that chitosan was successfully loaded on the surface of montmorillonite to prepare chitosan modified montmorillonite. The isoelectric point of modified montmorillonite was 7.84, and gallic acid in sucrose solution was mainly adsorbed by electrostatic force and amine group. The results of adsorption test showed that the modified montmorillonite had better adsorption performance for gallic acid. The optimal pH of chitosan modified montmorillonite for gallic acid adsorption in sucrose solution was 7.0, and the equilibrium time was 600 min. The adsorption process of chitosan modified montmorillonite for gallic acid was more in line with Freundlich model and quasi second order adsorption kinetic equation. The adsorption process was mainly multimolecular layer adsorption and chemical adsorption, and the saturated adsorption capacity reached 58.82 mg/g. Chitosan modified montmorillonite exhibited a good regeneration performance and good adsorption effect on phenolic acids in sucrose solution. It performed a promising clarifier for sugar.