Removal of neutral red dye from aqueous solution by adsorption onto rice bran

الملخص EN

This work is concerned with the study of locally available rice bran (Oryza sativa L) as an adsorbent for the removal of neutral red dye from solution as low-cost adsorbent in wastewater treatment for the removal of color which comes from textile dyes or other industries.

Adsorption process were occurred at different acidity of solution (pH = 3, 7, 11).

The experiments were repeated at different temperatures (20, 30, 40, 50°C) in order to measure the thermodynamic parameters (ΔH˚, ΔG˚, ΔS˚).

Rice bran showed good adsorption capacity against neutral red dye and can extract the dye from aqueous solution.

Adsorption isotherms of neutral red dye on bran from aqueous solution obeyed Freundlich adsorption isotherm indicating the heterogeneity of rice bran surface The thermodynamic parameter values are calculated as follow : ΔH˚ = -44.92 KJ.mol-1, ΔG˚= -5.06 KJ.mol-1, ΔS˚ = -136.05 J.mol-1.˚K-1 In conclusion, adsorption of on rice bran is exothermic process with relatively high thermodynamic parameters values.

The adsorption enhanced by decreasing temperature and with increasing acidity of the medium.

It can be concluded from the results of the present study that the process of adsorption of neutral red dye on rice bran may be used effectively to remove the dye from aqueous medium.