摘要
为了更好的利用胺基化磁性壳聚糖微球吸附分离苹果渣多酚的工艺,对其反应动力学和热力学进行了研究。主要采用Langmuir准一级动力学模型、Langmuir准二级动力学模型、Elovich方程及内扩散方程对吸附反应动力学过程进行拟合,并利用Langmuir等温吸附模型、Freundlich等温吸附模型及Temkin等温吸附模型对吸附反应热力学特性进行解析。结果表明:吸附动力学过程符合准二级动力学模型的描述,吸附温度越高,吸附速率常数和初始吸附速率越大,且平衡吸附量越高。吸附热力学过程符合Freundlich等温吸附模型,热力学参数ΔG<0,ΔH>0,ΔS>0,表明胺基化磁性壳聚糖微球对苹果渣多酚的吸附过程可以自发进行,并且是伴随着焓变>0的吸热过程。动力学及热力学研究为利用胺基化磁性壳聚糖微球进行苹果渣多酚的提取分离提供了技术依据。
The aim of this study was to study the kinetics and thermodynamics of apple polyphenols adsorption by aminated magnetic chitosan microspheres. The pseudo-first-order kinetics model, pseudo-second-order kinetics model, Elovich equation and pore diffusion equation were used to fit the adsorption kinetics process. Three isothermal adsorption models （Langmuir, Freundlich and Temkin） were used to analysis adsorption thermodynamics properties. The results showed that adsorption kinetics process conformed to the pseudo-second-order kinetics model. Adsorption rate constant, initial adsorption rate and equilibrium adsorption content tended to increase with the increasing of the temperature, and adsorption amount was higher. Adsorption thermodynamics conformed to Freundlich isothermal adsorption model. The results of thermodynamic parameters AG was below zero, AH was above zero, and AS was above zero. Which indicated that the adsorption of apple polyphenols to aminated magnetic chitosan microspheres was a spontaneous and exothermic process with the increasing of entropy. The kinetics and thermodynamics process can provide technical basis for the adsorption process of apple polyphenols using aminated magnetic chitosan microspheres.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2012年第16期264-269,共6页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家"十二五"科技支撑计划项目(2012BAK17B06,2012BAD31B01)
国家自然科学基金项目(31071550,31171721)
农业部"948"项目(2011-G8-3)
陕西省科技攻关(2009K01-20)
西北农林科技大学基本科研业务青年项目(QN2009073)
关键词
吸附
动力学
热力学
胺基化磁性壳聚糖微球
苹果渣多酚
adsorption, kinetics, thermodynamics, aminated magnetic chitosan microspheres, apple polyphenols adsorption
