Abstract:
This study investigates the optimization of biosorption of phenolic compound using
treated OPEFB biosorbent. The surface of biosorbent was modified by physical or
chemical treatment. The biosorption capacity for 2,3-dichlorophenol (2,3-DCP) are
higher than 2-chlorophenol. Therefore, 2,3-DCP was chosen as adsorbate and 0.1M
HCl treated OPEFB biosorbent was chosen as biosorbent in optimization. Full 2k
factorial design and central composite design were carried out. A full 25-1 factorial
design with five factors and two levels was used to screen the significant factor that
influence the biosorption process. These results were applied in the optimization using
Central Composite Design under Response Surface Design with three factor (initial
2,3-DCP concentration, pH of solution and OPEFB biosorbent dosage). The result of
experiment gave the optimun condition for 2,3-DCP biosorption, where: initial
concentration, pH and biosobent dosage were 200ppm, 5 and 0.1g, respectively). The
maximun biosorption capacity was 13.65 mg/g. Langmuir biosorption isotherm was
found to describe the biosorption of 2,3-DCP onto OPEFB biosorbent well at different
initial concentration of 2,3-DCP solution. The Langmuir model described the system
due to the monolayer coverage assumption on this model. Pseudo-second order was
found fitted for the biosorption of 2,3-DCP onto OPEFB biosorbent. Thermodynamic
constants of biosorption (ΔG°, ΔH° and ΔS°) were also evaluated, it indicated that
biosorption of 2,3-DCP was exothermic and not spontaneous process.
