Amir Mohammad Emami Rad - Department of Chemical Engineering, Islamic Azad University, Shahrood Branch, Shahrood, Iran
Ali Ramezani

Removal of melanoidins pigments from molasses spent wash was investigated using a new adsorbent. Solid adsorbents were fabricated from charcoal fly ash and clay with the proportion of 60 and 40 weight percent. The fabricated adsorbents were packed in a column and the molasses solution was pumped through the column. The impact of various contact times of the pigments and the adsorbents in the column on color removal efficiency was investigated. The experiments were conducted with various contact times of 30, 60, 90 and 240 min. Also, the effect of influent molasses concentration on the performance of the adsorbents was evaluated. The effluent samples were taken from the column at a time interval of 30 min. The obtained results revealed that maximum color removal efficiency of 72 percent was achieved with molasses concentration of 6 g/l and contact time of 240 min. The obtained results from the fresh and regenerated adsorbents were compared. The achieved data showed that 90 percent of the capacity of the fresh adsorbent was recovered after regeneration process. It was also concluded that the regenerated adsorbents were able to remove 65 percent of the color from the molasses solution. Langmuir and Freundlich isotherm adsorption models were investigated to interpret the experimental data. The obtained data were well represented by Langmuir adsorption model. The constants of the isotherms and the maximum adsorption capacity of the adsorbents were calculated.

Molasses, Adsorption, Calcined clay, Fly ash, semi batch system