Investigation of dye removal from textile wastewater by means of response surface method

The main purpose of this article is to apply response surface method to analyze the residual dyes removal independent variables from the experimental data for dye adsorption onto alkali-activated sand as natural adsorbent from textile wastewater. The independent variables are contact time (3-30min) and adsorbent dosage (12.5-100 g) and the dependent variables are percentage of dye removal and dye adsorbed amount per alkali-activated sand as responses. The effect of the variables, their interaction with each other, the fitted model equations, the adequacy and desirability of the model was evaluated by RSM. Response surface method to analyze the residual dyes removal, which resulted in about 70% dye removal and 30 x 10(-3) mg/g dye adsorbed, with 0.983 of desirability for fitted model. Finally, the initial dye concentration effect was investigated.