Batch and Fixed Bed Comparative Study on the Bio-sorption Properties of Sphagnum Cymbifolium (Moss) on Methylene Blue Dye, Bismarck Brown Y Dye, and Indigo Dye

The adsorption properties of Sphagnum cymbifolium (moss) on methylene blue dye, Bismarck brown Y dye, and indigo dye was studied using both the batch and fixed bed methods. This was done in other to compare the degree of effectiveness of each of the methods over each other. The biomass was characterized using the scanning electron microscope (SEM), as well as Fourier Transform Infrared spectroscope before and after adsorption in order to determine the functional groups responsible for the adsorption. The amount of dye adsorbed per unit mass of the biomass (q_e) was calculated and found to be dependent on all the variables investigated e.g. pH, contact time, biomass dose, dye concentration and temperature. Optimal pH of 2 was determined for the adsorption of Bismarck brown Y dye, and indigo dye, while a pH of 4 was determined for methylene blue dye. The q_e value for the fixed bed adsorption was 21.86mg/g for methylene blue dye, 13.50mg/g for Bismarck brown y dye, and 4mg/g for the indigo dye with corresponding values of 20.08mg/g, 12.60mg/g and 2.28mg/g for the batch process. These results show a better adsorption in the fixed bed technique over the batch process. Indigo dye was found to be the least adsorbed, while methylene blue dye was the most adsorbed. The adsorption pattern was fitted for Langmuir adsorption isotherm model.