THE REMOVAL OF METHYLENE BLUE USING BANANA STEM/SUGARCANE BAGASSE HYBRID ADSORBENT AND ITS KINETIC STUDY

Abstract

Environmental pollution from dye-used industry not only in the form of dust contamination but in the form of water pollution as well. The wastewater from spillage and washing water where dyeing of starch solution and staining process causes the damage to the river ecosystem. This occurrence of water pollution will disrupt the aquatic life, decrease the qualities of the water, as well as causing the biological, physical and chemical consequences. Thus, environmentally-safe water treatment is significantly required to treat the textile wastewater before discharging the effluent. This study was to evaluate the potential of hybrid adsorbent made from banana stem and sugarcane bagasse to remove methylene blue dye in aqueous solution. The dried materials were treated with Potassium hydroxide, KOH for 24 hours to remove its lignin as well as to activate its cellulose part before weighted them evenly to produce hybrid adsorbent. The batch experiments were conducted by mixing two different adsorbent dosages (0.2 g and 0.6 g) into three different initial concentrations of methylene blue; 40 ppm, 70 ppm and 100 ppm each in a conical flask with total contact time of 90 minutes for each sample. The concentrations of methylene blue solution were evaluated for every 15 consecutive minutes using ultraviolet-visible spectrophotometry (UV-VIS). Two kinetic models which pseudo first-order and pseudo second-order model were applied to understand the mechanism and behaviour of these adsorption processes. Overall, methylene blue adsorptivity by both hybrid adsorbent dosages were seen to directly proportional to contact time and more likely to have desorption until the equilibrium condition had achieved. Meanwhile, 0.6 g of hybrid adsorbent had shown higher efficiency of adsorption. The best adsorption activity was at the initial dye concentration which was 40 ppm using 0.6 g of hybrid adsorbent which resulted a maximum adsorption of 97.3% within 90 minutes. The adsorption process in this study followed the pseudo second-order model with R2 is 0.999. This research has proved the capability of hybrid adsorbent to remove methylene blue in aqueous solution and is recommended to be used in the wastewater treatment.