Adsorption of methylene blue from aqueous solution on the surface of wool fiber and cotton fiber

Abstract

Adsorption of dye methylene blue from aqueous solution on the surface of sheep wool and cotton fibers was accomplished under the optimize conditions of temperature, concentration, pH, stay time duration and quantity of adsorbent. Spectrometric technique was used for the measurements of concentration of dye before and after adsorption. The percentage removal and distribution constant (K_D) values for the removal of of methylene blue were also calculated. The values of % adsorption data for methylene bluesheep wool system show better adsorption capacity as compared to methylene bluecotton fiber system. The applicability of Langmuir and Freundlich adsorption isotherm equations for the present system was also tested. The experimental data are fitted to the Langmuir and Freundlich isotherm equations. The values of their corresponding constants were determined from the slope and intercepts of their respective plots. Thermodynamic parameters like ΔG °, ΔH ° and ΔS ° were calculated on the basis of Langmuir constant K. The methylene bluesheep wool system show non spontaneous and exothermic behavior, while methylene bluecotton fiber system show spontaneous and endothermic behavior. The results of these investigations suggested that natural adsorbents can be utilized as adsorbent materials, because of their selectivities for the removal of dyes.

Journal of Applied Sciences and Environmental Management Vol 9(2) 2005: 29-35