Adsorption of methylene blue onto chemically modified coconut palm frond (cocos nucifera) powder / Mohamad Shahrizad Bin Zainal Abidin

In this study coconut frond treated with sulfuric acid has been used as the low-cost adsorbent in adsorption of methylene blue (MB) from aqueous solution. Adsorption technique gives more advantage compared to other techniques for the removal of methylene blue (MB) from wastewater. The used of low cost adsorbent is more preferable compare to common adsorbent which is activated carbon which is expensive.
Parameter of the analyses such as solution pH (2-10), SACF dose (0.01 – 0.05 g), contact time, initial concentration (20, 30, 40 mg L-1). The equilibrium data were analysed using the Langmuir and the Freundlich isotherm. The kinetic process regarding to the adsorption of methylene blue (MB) onto SACF were described by applying the pseudo-first-order and pseudo-second-order kinetic model. FTIR analysis showed that a
large number of carbonyl and hydroxyl group presence on the surface of SACF. The pHzpc of SACF was determined to be 7.19 in which the adsorption of methylene blue (MB+) that considered as cationic dye was favourable. The Langmuir and Freundlich isotherms models were employed in order to investigate the adsorption behavior of SACF and the best fit to the data was obtained with the Langmuir isotherm model with maximum adsorption capacity (qmax) was found to be 62.5 mg g-1 at pH 6, shaking speed of 120 strokes per minutes and at temperature at 303 K. So, it shows that adsorption process was monolayer with the coverage of the MB molecule only takes place at the outer surface of SACF.