Optimization study of Orange 16 dye sorption from aqueous systems using sawdust wastes [articol]

Abstract

The application of sawdust waste as adsorptive material into an aqueous system containing the textile Orange 16 reactive dye is studied. The main treatment step is based on sorption followed by solid/liquid separation by sedimentation and filtration. All experiments are performed on a laboratory scale set-up in order to establish the optimal operational parameters (e.g., sawdust quantity, pH, sorption time, temperature) for high removal efficiencies of textile synthetic reactive dye - Orange 16. Variables concerning the sawdust quantity (0.2-0.7 g per 25 mL), pH (0.3-4), and sorption time (12-150 min) are considered in order to appreciate the sorption efficiency. An empirical model is proposed by a central composite rotatable design of third order (2³), considering these variables as independent ones (xi), while the dye removal is chosen as optimization criteria (Y, %). The optimal values are in good agreement with the experimental data (i.e. the data average deviation is lower than ±10%).