摘要
目的:考察低取代羟丙纤维素作为吸附层析介质在水溶液中富集吸附茶黄素的热动力学。方法:将低取代羟丙纤维素与茶黄素溶液按一定的固液比置于不同温度下,一定时间后检测溶液中茶黄素浓度的变化规律,从而得出茶黄素在低取代羟丙纤维素中的吸附热动力学参数,并以Langmuir与Freundlich吸附等温模型来描述其吸附行为,根据方程计算了热力学参数自由能(△G^θ)、焓(△H^θ)及熵(△S^θ)。结果与结论:Langmuir吸附模型能够较好地模拟实验数据,吸附动力学参数揭示了其吸附茶黄素的过程主要为物理过程,且不同单体间随焓熵的变化呈现出酯型强于非酯型简单茶黄素。
Objective:Low-substituted hydroxypropyl cellulose was used as an adsorbent for the adsorption of theaflavins from aqueous solutions. Method:Batch experiments were carried out to investigate the effect of temperature on sorption efficiency. The adsorptive thermodynamic properties of theaflavins from water onto low-substituted hydroxypropyl cellulose were studied. The Langmuir and Freundlich isotherm models were employed to discuss the adsorption behavior. Thermodynamic parameters such as △^θ,△H^θ and △S^θ were calculated. Result and Conclusion:The results indicate that the equilibrium data are perfectly represented by Langmuir isotherm model. Thermodynamic study reveals that it is an exothermic process in nature and mainly physical adsorption. Finally, Gallyol type theaflavins was better than simple theaflavins based on the adsorption of low-substituted hydroxypropyl cellulose.
作者
涂云飞
TU Yun-fei(Key Laboratory of Tea Resource Multi-applied Technology of Zhejiang Province, Hangzhou, Zhejiang 310016, China;China National Supply and Marketing Cooperatives Hangzhou Tea Research Institute, Hangzhou, Zhejiang 310016, China)
出处
《浙江化工》
CAS
2019年第10期30-36,共7页
Zhejiang Chemical Industry
基金
“十三五”国家重点研发计划资助项目“茶叶活性成分绿色制备及防腐、保鲜功效与应用技术研究”（2016YFD0400805）
关键词
低取代羟丙纤维素
茶黄素
吸附
等温
热动力学
low-substituted hydroxypropyl cellulose
theaflavins
adsorption
isotherm
thermodynamics
