The results of the research on the ability of adsorption of dye on polyester
fibers at a temperature of 98?C are presented in this paper. The fibers
were previously modified in aqueous solutions of NaOH, KOH or Al(OH)3.
Typically, the dyeing of the fibers takes place at high temperatures and
under pressure in the presence of the carrier. Previous processing before
adsorption-dyeing, alkali hydrolysis, changes the surface morphology of
polyester fibers. Based on dye exhaustion results, it was found that the dye
adsorption on modified polyester fibers (degree of exhaustion 18.2 %, for a
dye concentration of 200 mg?dm-3 and adsorption time of 5 min) has been
bigger than adsorption to unmodified fibers (degree of exhaustion 10 %, for
a dye concentration of 200 mg?dm-3 and adsorption time of 5 min). The
five-parameter nonlinear model of Fritz-Schlunder is the most efficient in
simulating isothermal adsorption of disperse dye on polyester fibers (the
correlation coefficient is 0.995). Other adsorption models,
Dubinin-Radushkevich, Marczewski-Jaroniec and Hill give poorer results and
cannot be used to explain the adsorption of the disperse dye for polyester
fibers (the correlation coefficients are 0.891, 0.922 and 0.973,
respectively).