Optimization of Activated Carbon Production from Eucalyptus Wood Using H3PO4 as the Activating Agent

  • Kanokwan Seerod Student, Master of Engineering Program in Chemical Engineering, Department of Chemical Engineering, Faculty of Engineering, Khon Kaen University, Thailand
  • Varinrumpai Seithtanabutara Assistant Professor, Department of Chemical Engineering, Faculty of Engineering, Khon Kaen University, Thailand
Keywords: Activated carbon, Phosphoric acid, Response surface methodology


Activated carbons were prepared from eucalyptus wood residue via chemical activation with H3PO4 as a chemical activating agent. MINITAB (version 16) software was used for investigation the effects of acid concentration (0.5-2 M), carbonizing temperature (500-700C) and carbonizing time (60-120 min) on specific surface area. Variance analysis and RSM technique were applied to describe the polynomial model as a function of experimental parameters and its significant parameter. Model with multiple correlation coefficients of determination R2 and Radj2 of 0.9725 and 0.9230, respectively, was proposed. Acid concentration was the most significant factor that influenced on the specific surface area. AC with high specific surface area of 365.254 m2/g was obtained at the optimum condition; 2M of H3PO4, 700C and 120 min. Extra investigatain at this condition was done by using smaller precursor impregnated in stronger H3PO4 concentration of 8M. It was found that the activated carbon AC with developing mesoporosity and improved surface area of 812.84 m2/g was produced. The physical and structural properties of activated carbons were characterized by TGA, SEM and FTIR. Also their porous structures were determined by adsorption/desorption of N2 at 77 K.


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