DOI: 10.36347/sajb.2015.v03i08.002

Pages: 644-649

Dyes have many applications in various industries. In addition to Mutagenic and carcinogenic potential to humans, these materials cause the production of toxic byproducts in the aqueous solutions. In the present study, the adsorption potential of Red mud in a batch system for the removal of Acid Red 18 dye (AR18) from aqueous solutions was investigated. The effects of pH, contact time, biomass and Acid Red 18 dye concentrations were studied. Residual concentration of Acid Red 18 dye was read using a spectrophotometer at a wavelength of 508 nm. In optimal conditions of operation including pH=3, contact time=75 minutes, adsorbent dose 4 gr/L and the initial concentration of Acid Red 18 dye= 25 mg/l, removal efficiency of the process was obtained over 98.9%. The adsorption equilibriums were analyzed by Langmuir, Freundlich, Temkin and BET isotherm models. It was found that he data fitted to Langmuir (R2=0.997) better than isotherm other models. Batch kinetic experiments showed that the adsorption followed pseudo-second-order kinetic model with correlation coefficients greater than 0.997. According to achieved results, it was defined that Red mud not only was an inexpensive absorbent, but also a quite effective factor in removal of Dyes from water and wastewater. The results showed that Red mud was an inexpensive absorbent and quite effective in removal of Dyes from aqueous solutions.