PERTANIKA JOURNAL OF TROPICAL AGRICULTURAL SCIENCE

The adsorption of phenol, from aqueous solutions on activated carbon from waste tyres, was studied in a batch system at different initial concentrations (100-500mg/L) at 30°C for 48 hours. The activated carbon was prepared using the two-step physiochemical activation, with potassium hydroxide (KOH) at ratio KOH/char = 5. The carbonization process was done at 800°C for 1 hour with nitrogen flow rate 150ml/min, followed by the activation with the carbon dioxide flow rate 150ml/min at 800°C for 2 hours. The adsorption isotherms were determined by shaking 0.1g of activated carbon with 100ml phenol solutions. The initial and final concentrations of phenol in aqueous solution were analyzed using the UV-Visible Spectrophotometer (Shimadzu, UV-1601) at a wavelength of 270nm. Experimental isotherm data were analyzed using the Langmuir and Freundlich isotherm models. The equilibrium data for phenol adsorption could fit both isotherm models well with the Rs² value of 0.9774 and 0.9895, respectively. The maximum adsorption capacity of the adsorbent obtained from the Langmuir model was up to 156.25 mg/g.