高粱壳色素上染毛织物的动力学和热力学

Dyeing kinetics and thermodynamics of sorghum husk colorant onto wool fabric

为研究高粱壳色素上染毛织物的染色机制,给优化染色工艺提供理论指导,应用动力学、热力学模型对高粱壳色素上染毛织物的实验数据进行拟合。结果表明,高粱壳色素上染毛织物符合准二级动力学模型。染色温度在80~100℃范围内,随着温度升高,染色速率、半染时间及扩散系数均增大。高粱壳色素上染毛织物的吸附等温线符合朗格缪尔型,属于单分子层吸附。染色温度在80~100℃范围内,随着染色温度的升高,上染到毛织物上的高粱壳色素量增加,吸附饱和值升高;并且染色热和染色焓变均为正值。

Dyeing kinetics and thermodynamics of sorghum husk colorants on wool fabric were investigated in order to explain of the dyeing mechanisms and provide theoretical basis for optimization of the dyeing conditions. The results showed that the adsorption process of sorghum husk colorants on wool fabrics could be well described by the pseudo-second-order kinetic model. The dyeing rate constant,the half-dyeing time and diffusion coefficient increased with the increasing dyeing temperature from 80 ℃ to100 ℃. The adsorption isotherm was identified to be Langmuir type,which belonged to monolayer adsorption. The dye adsorbed at equilibrium and adsorption capacity increased with the increasing dyeing temperature from 80 ℃ to 100 ℃. The values of entropy change and enthalpy change of adsorption process were positive.