摘要
本文探究了天然染料胡桃醌与头发相互作用的吸附动力学及热力学,探究其染色机理。结果表明,染发过程中,头发对胡桃醌的吸附符合拟二级动力学模型,且染色速率和染色平衡吸附量均随着温度的升高而增大,在333 K下头发对胡桃醌的平衡吸附量最大,为18.957 mg/g。通过实验和理论的结合发现,Freundlich和Langmuir吸附理论均能较好的拟合吸附数据。但相比而言,Freundlich吸附理论可以更好地表述头发对胡桃醌分子的吸附作用。此外,吸附热力学数据表明吸附过程是自发吸热的物理吸附。ΔG<0,说明头发对胡桃醌的吸附是自发进行的,ΔH>0说明吸附为吸热反应,温度升高有利于吸附的进行。由Arrhenius方程求得活化能Ea为30.09 KJ/mol,表示吸附属于物理吸附。
The kinetic and thermodynamics of juglone sorption onto yak hair as a model system were investigated.It was found that the sorption kinetics of juglone on hair followed a pseudo-second-order kinetic model.The equilibrium sorption capacity increased as the temperature increasing from 303 to 333 K.The maximum equilibrium sorption capacity was 18.957 mg/g at T=333 K.By the combination of experiment and theory,Freundlich and Langmuir isothermal equation can fit adsorption data well.But the adsorption of juglone onto hairs was better described by the Freundlich isothermal equation.In addition,according to the adsorption thermodynamics parameters,the adsorption of juglone onto hairs was spontaneous,endothermic and increasing entropy process.The process of adsorption was mainly physical adsorption.During the isothermal equation,the negativeΔG suggested that the adsorption process was spontaneous,ΔH was greater than 0,indicating that the adsorption was exothermic.An activation energy of sorption had also been evaluated with the pseudo-second order rate constants,the E a in this study was 30.09 kJ/mol,indicating that the adsorption was a typical physical adsorption.
作者
訾慧敏
王建国
陶涵清
张昕昕
郝泽坤
史宏艺
高海燕
ZI Hui-min;WANG Jian-guo;TAO Han-qing;ZHANG Xin-xin;HAO Ze-kun;SHI Hong-yi;GAO Hai-yan(School of Chemical and Material Engineering,Jiangnan University,Wuxi 214122,China)
出处
《天然产物研究与开发》
CAS
CSCD
北大核心
2018年第3期362-367,共6页
Natural Product Research and Development
基金
江南大学大学生创新项目(2017244Y)
江苏省产学研前瞻性联合研究项目(SBY2015020417)
