Removal of Directs Dyes from Wastewater by Cotton Fiber Waste

Abstract

Environment protection is a precondition for sustained growth and a better quality of life for all peoples on earth. Aqueous industrial effluents are the main sources of pollution. Among the compounds of these effluents, dyes are particularly resistant to discoloration by conventional methods, and discharges present many problems that must be supported. Synthetic dyes are used in industrials sectors; especially in the textile, industry. There is a certain selectivity of raw cotton fibers for the different types of dyes, depending on the chemical structure of the dyes. We note that this affinity is very high for direct dyes and decreases for reactive dyes and pigment dyes. This study focuses on the elimination of direct dyes wastewater from the textile industry, by their adsorption on waste very adsorbent cotton fibers, the removal rate greater than 75% for the three types of direct dyes used, a mathematical of the adsorption isotherms of and their kinetics of adsorption was made and shows the mathematical models of adsorption curves, it shows that the direct dye red 216 adsorbs very easily and the saturation is obtained after 30 mn and the direct yellow 4 dye s' adsorbs regularly and reaches the saturation 100 mm, which shows that the adsorption is done according to the spatial structure of the dye and the porosity of the cotton this technique is interesting, it allows to recover adsorbate cotton as raw material for several uses and at very low cost.