The removal of dyes from solution by adsorption onto alginate calcium beads has been studied. A methodology of surface response was used, this kind of designs estimate the coefficients of a quadratic polynomial mathematical model, whose essential interest is to be able to predict in any point of the experimental region, the values of the response. The effects of initial concentration, pH, adsorbent dose and temperature were investigated. A full factor design was performed to determine the effect of the main parameters and their mutual interaction for the adsorption process. Using the experimental results, a linear mathematical model representing the influence of the different parameters as well as their interactions was obtained; it shows that the temperature is the most significant parameter affecting the dyes' removal. The effect of various experimental parameters and optimal experimental conditions was ascertained by response surface methodology using the Doehlert model.
Keywords: Doehlert; Dyes; adsorption; alginate; response surface methodology.