Removal of basic and acid dyes from aqueous solutions by a waste containing boron impurity

In this study, batch experiments were carried out for the sorption of basic blue 41 (BB 41), and acid blue 225 (AB 225) onto boron waste (BW) from boron enrichment plant. The operating variables studied are the initial dye concentration, contact time, solution pH, and adsorbent dosage. The experimental equilibrium data were analyzed by using various adsorption isotherm models and the results have shown that the adsorption behavior of AB 225 and BB 41 could be described well reasonably by Langmuir and Temkin isotherms, respectively. Kinetics studies indicated that the adsorption of both dyes follow pseudo-second-order kinetics. The sorption of basic dye increased at high pH values, whereas the opposite was true for acidic dye. The results indicate that BW could be employed as low-cost alternatives to the commercially available adsorbents in wastewater treatment for the removal of acid and basic dyes. (C) 2009 Elsevier B.V. All rights reserved.