Malachite green dye decolorization on immobilized dead yeast cells employing sequential design of experiments
Abstract
The use of low-cost, potential, locally available and eco-friendly adsorbents has been investigated as an ideal alternative to the current expensive methods of removing dyes from wastewater. Sequential Plackett-Burman design (PBD) model was used to screen out the most significant factors and Box-Behnken design (BBD) to study the combined effects of interaction between the variables selected by PBD. Second-order polynomial regression model was applied which was statistically validated using analysis of variance. Maximum decolorization 96.25% obtained at pH 6.88, dye concentration 188.01mg/L and adsorbent dose 0.49g (dead yeast cells) after 60min. Kinetic studies showed that the adsorption follows pseudo-second order kinetics and maximum 61% desorption obtained. Negative values of Gibbs free energy change (ΔG°) showed that the adsorption was feasible and spontaneous and negative values of enthalpy change (ΔH°) confirmed exothermic adsorption.
- Publication:
-
Ecological Engineering
- Pub Date:
- October 2012
- DOI:
- 10.1016/j.ecoleng.2012.07.001
- Bibcode:
- 2012EcEng..47..291S
- Keywords:
-
- Yeast cells;
- Malachite green;
- Adsorption;
- Kinetics;
- Thermodynamics;
- Desorption