分散红60在超临界CO_2染色中的动力学及热力学

Kinetics and thermodynamics of dyeing polyester with C. I. Disperse Red 60 in supercritical carbon dioxide

在自行研制的生产型超临界流体染色样机中,对分散红60染料在超临界CO2染色过程动力学进行研究。结果表明,染料在涤纶中的扩散系数随温度升高而增大,根据Arrhenius方程求得分散红60在超临界流体中染色涤纶的扩散活化能为22.22 kJ/mol,远小于在水介质中染色的扩散活化能163.84 kJ/mol。通过对分散红60染料在超临界CO2染色过程中的某些热力学参数研究表明,染料在超临界流体的上染量与染料用量成线性关系,上染过程是染料在纤维和流体之间的分配关系,分配系数和染色亲和力随温度升高而减小,染色热和染色熵均为负值,二者分别为-23.63 kJ/mol和-26.09 J/(mol·K)。

Based on the developed dyeing prototype,the kinetics of dyeing of polyester with C.I.Disperse Red 60 in supercritical CO2 was studied.The diffusion coefficient of the dye in PET in supercritical CO2 increases with the increase of temperature.The activation energy calculated with the Arrhenius equation is 22.22 kJ /mol,which is far lower than the activation energy in traditional water dyeing process of 163.84 kJ /mol.The thermodynamics of dyeing of polyester with C.I.Disperse Red 60 in supercritical CO2 was investigated.The uptake of C.I.Disperse Red 60 in PET fiber is linear to the dye concentration applied.The SC-CO2 dyeing is actually a distribution process of the dye between fiber and the fluid.The distribution coefficient and the thermodynamic affinity of the dye decreases with the increase of temperature.Both the enthalpy and entropy of dyeing are negatives,which is-23.63 kJ /mol and-26.09 J /（mol.K） respectively.