VOL. 11, NO. 9, MAY 2016 ISSN 1819-6608 ARPN Journal of Engineering and Applied Sciences © 2006-2016 Asian Research Publishing Network (ARPN). All rights reserved. www.arpnjournals.com 6186 ADSORPTION OF METHYLENE BLUE IN AQUEOUS SOLUTION BY MUSA PARADISIACA STEM POWDER Nurul ‘Uyun Ahmad, Ahmad Faris Ahmad Azli, Noratiera Che Mat, Fathin Nor Faridah Mohamed Nawi and Mohd Hakimi Othman Faculty of Chemical Engineering, Universiti Teknologi MARA, Bukit Besi, Dungun, Terengganu, Malaysia E-Mail: nurul’uyun@tganu.uitm.edu.my ABSTRACT In Malaysia, textile industry contributes the most to the wastewater that has led to environmental problems. Most of the dyes used in textile industries are toxic in nature with suspended carcinogenic and mutagenic effect that affects aquatic lives and human beings. The focus of this study is to identify the potential of Musa paradisiacal stem (banana stem) which commonly available waste material that are low-cost, natural and an eco-friendly bio-sorbent for the economical removal of methylene blue (MB) dye in aqueous solution. In this study, the stem is acting as an adsorbent. Batch model experiments are conducted to determine the effect of pH and the initial concentrations of MB solutions, adsorbent dosages and its contact time in methylene blue solutions towards the efficiencies and adsorptive (%) of the stem as a MB removal agent. The stem is dried and treated with Potassium Hydroxide to remove its lignin and to activate its cellulose part. The concentrations of MB solution are analyses using ultraviolet-visible spectrophotometry (UV-VIS) before and after the adsorption processes. The MB uptake has increased with the increased of pH value. The MB adsorption increased simultaneously with the adsorbent dosages and contact times. The maximum adsorptive is identified as 91.47% at 70 ppm of MB solution at pH 12 using 0.6 g of adsorbent dosage. The best adsorbent dosage is found to be as 0.6 g due to its higher adsorptive in all ranges of concentration and pH of the dye solutions. However, the removal percentage (%) decreases with the increased of initial MB concentrations. In conclusion, this study recommends that Musa paradisiacal can be used effectively in the adsorption of MB in aqueous solution. Keywords: color removal, cationic dyes, mutagenic, water pollution, biosorption. 1. INTRODUCTION Methylene Blue (MB) is a dye that forms a heterocyclic aromatic compound which consisting of dark green crystals. It is commonly used in textile and other industries such as rubber, food, paper, plastic, paint, cosmetic and pharmaceutical industry [1]. The dye has a highly toxicity that will give a bad effect on the aquatic lives [2]. It will reduce the oxygen content of water and this consequently avoids the photosynthesis of aqueous flora then impedes the solubility of gases in water [1]. Moreover, the human life will be infected with a serious disease due to the environmental instability caused by methylene blue that contained in the water [3]. Therefore, the removal of methylene blue from aqueous solution is important to prevent the continuous environmental pollution. According to [4], many dyes are toxic to some microorganisms and may cause direct destruction or inhibition of their catalytic capabilities. Hence, there are a lot of technique such as biological treatment, chemical oxidation, coagulation, ozonolysis, electrochemical degradation and reverse osmosis that have been investigated for removal of MB in aqueous solution [5]. Unfortunately, all listed methods are not widely used due to their high cost and economical disadvantage [6]. Amongst the numerous techniques, adsorption is the technique that is most widely used in the removal of dyes from aqueous solutions due to the low cost, sustainable, natural and eco-friendly biosorbent [7]. Adsorption is rapidly gaining prominence among the treatment technologies. In [7] noted that adsorption can produce high-quality water, while also being a process that is economically feasible. The physical characteristics of the adsorbents such as surface area, porosity, size distribution, density and surface charge that have high influence in the adsorption process [8]. As a result, there has been a great interest in developing new adsorbent materials with diverse compositions, properties and functionalities Normally, after harvesting the fruit, Musa paradisiacal stem is cut down and thrown away, mostly as a waste. This action has constantly caused the air pollution due to the open burning activity of the mass waste of Musa paradisiacal stem. Besides, it is also wasting the benefits that contain in the stem as it is actually possessed some valuable characteristic such as high in fiber. From the recent research, the stem contains about 60-65% of cellulose, about 6-19% of hemi-cellulose and 5-10% of lignin with 3-5% pectin [9]. Therefore, the purpose of this work is to investigate the ability of Musa Paradisiaca stem as an adsorbent of MB in aqueous solution. A batch model experiments are conducted to determine the effect of pHs and the initial concentrations of methylene blue solutions, adsorbent dosages and its contact time in methylene blue solutions towards the efficiencies and adsorptive (%) of the stem as a methylene blue removal agent.