engleski

THERMODYNAMIC INVESTIGATION OF DISPERSE DYES SORPTION ON POLYESTER FIBERS

Тhe thermodynamics of sorption during the dyeing process of raw polyester fibers with disperse dye was studied in this article. Dyeing of fibers is carried out by a discontinuous batch process, according to standard procedures with varying of the initial dye concentration and the dyeing temperature. Several of the accepted models for calculation of thermodynamic parameters were used which define and clarify the sorption of disperse dyes on polyester fibers. High functionality of variables for the calculation of basic thermodynamic parameters was determined, which confirmed the validity of the results. Depending on the method of calculation, the change of free energy during the dyeing of the polyester was negative (-10 – -40 kJ·mol-1), which corresponds to the spontaneous and mainly the physical process of sorption. A positive value for the change in enthalpy during dyeing (1.1×10-2 – 2.9×101 kJ·mol-1) reflects the endothermic nature of the interactions, and a relatively lower value characterizes the physisorption phenomenon. A positive value for the change in entropy (1.1×10- 4 – 1.5×10-1 kJ·mol-1·K-1) confirms that it is a physical sorption.

polyester, modification, dyeing, disperse dye, thermodynamics parameters.

Tehnološki fakultet u Leskovcu, Univerzitet u Niš, Srbija