STUDIES ON THE IMPACT OF FLOW RATE AND BED HEIGHT ON THE FIXED BED ADSORPTION OF METHYLENE BLUE DYE, BISMARCK BROWN Y DYE, AND INDIGO BLUE DYE ON TO CEDRUS LIBANI (ELIZ ABETH LEAF) BIOMASS

Objective: One of the objectives of this work includes to expand the field of application of natural biomass for the treatment of dye effluents from industrial wastes. In addition, it is aimed at elucidating the dependency or otherwise of flow rate and bed height on adsorption using the fixed bed technique method of adsorption. Methods: The biomass was characterized by scanning electron microscopy (SEM) in order to examine the morphology of the biomass. The screened biomass samples were characterized at 1000 x magnification, and 500 x magnification respectively for their surface morphologies. This was done using a scanning electron microscope (FEI–inspect/OXFORD INSTRUMENTS–X–MAX), which was equipped with an energy dispersive x-ray (EDAX) spectrophotometer employed for the elemental composition analyses. It was equally characterized with Fourier Transformed Infrared Spectroscopy (FTIR) before and after adsorption to ascertain the functional growth responsible for the adsorption. This was done using a Fourier Transformed Infrared (FTIR) Spectrophotometer (Perkin-Elmer, England) in the wavelength range of 350-4000 nm. Results: Results for the biomass morphology obtained through the Scanning Electron Microscopy (SEM) showed the presence of some tiny pores. These pores represent sites where dye molecules could be trapped in the course of the adsorption. The result from the Fourier Transformed Infrared Spectroscopy (FTIR) after adsorption show that C-H, C ≡ H, and C ≡ C functional growth were responsible for the adsorption. For the methylene blue dye, at the flow rate of 20m3/s, the amount of dye adsorbed was 8.40 mg/g, 11.30 mg/g at 30m3/s and 13.64 mg/g at 40m3/s. For Bismarck brown Y dye, at the same range of flow rate, the amount of dye adsorbed ranged from 4.71 mg/g to 9.78 mg/g. indigo was the least adsorbed at the same range of flow rate. The values obtained ranged from 2.80 mg/g to 8.00 mg/g. In addition, at the bed height of 4.0–6.0x10-2(m), the amount of dye adsorbed ranged from 5.15 mg/g–24.62 mg/g for methylene blue dye. Within the same range of bed height, the amount of dye adsorbed ranged from 8.20 mg/g–15.00 mg/g for Bismarck brown Y dye, and 5.66 mg/g–14.86 mg/g for indigo dye. Conclusion: From the results obtained, it is clearly seen that methylene blue dye was the most adsorbed, while the indigo dye was the least adsorbed within the same flow rate and bed height ranges. In addition, the three classes of dyes used in these investigations, which represent Cationic, Anionic and Neutral dyes, can adsorb on to Cedrus libani (Elizabeth Leaf) at various degrees. Also, the amount of dye adsorbed is dependent on the flow rate and bed height within the range of experimental consideration. In each of the analyses, three different experiments were performed, and the mean values reported with their standard deviations.