The effect of cationic modification of cotton fabrics, using commercial agent Sintegal V7conc, on reactive dyeing characteristics was studied in this work. The changes after cationization and their effects on practical application of reactive dyes were identified by various methods. Cationically modified fabrics have more positive zeta potential, compared to untreated fabrics, which has a favorable influence on reactive dyeing in the absence or presence of salt. Color intensities of reactive dyes reached their maximum on samples treated with the highest concentration of Sintegal V7conc solution and dyed in the presence of standard salt concentration. The results obtained indicate that color intensity increase is a combined contribution of both salt and cationic agent on adsorption and fixation of reactive dyes on cotton.

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The surface of the bottle gourd shell (BGS), a solid agricultural residue of Lagenaria vulgaris Ser. was chemically modified using a cationic surfactant, hexadecyltrimethylammonium chloride (HTAC). The success of the modification was confirmed by FTIR spectroscopy. Chemical characterization of the lignocellulosic BGS biomass and the surfactant modified bottle gourd shell (MBGS) was carried out using the compositional and elemental analysis. The amount of surfactant sorbed on the BGS surface was measured as a function of the surfactant bulk concentration. Sorption isotherms were used to verify self-assembly models of cationic surfactant sorption onto oppositely charged MBGS substrates. The shape of sorption isotherms was applied to describe the behavior of the surfactant/BGS system. The surfactant modified shell was tested as a sorbent for the removal of phosphate and nitrate from contaminated aqueous solutions. The sorption of anionic pollutants on MBGS was performed in a series of batch sorption experiments at 20 o C. It was found that the MBGS yielded sorption efficiency was 40% for phosphate and 22% for nitrate. The sorption mechanism involving the ion exchange might be responsible for the uptake of anions. The morphology and surface properties of the MBGS sorbent before and after sorption of anionic pollutants were analyzed by SEM methods. Compared to other non-surfactant sorbents, the advantage of MBGS as a sorbent is that it can be used for the removal of anionic pollutants not only from aqueous solutions but also from the emulsified oil wastewater or nonpolar effluents.

In this work, the effects of single and combined corona discharge (CD) and biopolymer chitosan treatment (CS) on the sorption properties and dyeability of woolen fabric were studied. Physical and chemical changes on the fiber surface were assessed by using different methods. It has been confirmed that wettability and dyeability of wool were improved after single and combined treatments. The changes in elemental composition of wool fiber surface were followed by means of X-ray photoelectron spectroscopy. The relationship between chemical changes and both wettability and dyeability after CS is discussed. On chitosan treated samples, the color intensity increased uniformly with increasing chitosan concentration. The samples treated with combined treatment (corona/chitosan) had the highest color intensity, due to synergistic effect of the treatments.

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