Study of Adsorption Isotherm of Nanionic Dyes on Nylon 6 Fibers

Sorption isotherms of three nonionic disperse dyes, Blue 3, Red 1 and Yellow 3 on nylon 6 fibers were studied at 90 and 98C. A remarkable deviation from Nernst trend was obtained for all cases. Performance of Dual-Mode sorption model which is consisting of Langmuir mechanism for covering of initial curvature zone and Nernst model for the later nearly linear part was tested. Dual-Mode fitting was appeared to be in good agreement with experimental data. In addition, temperature effect on Dual-Model isotherm and on saturation point of fiber at two selected temperature was compared. The results showed the capacity of fiber for solution sorption is increased by increasing the temperature; however an important part of the total sorption was still followed as Langmuir isotherm.