Four activated carbons were produced by two-stage process as followings; semi-carbonization of indigenous biomass waste,
i.e. cotton stalks, followed by chemical activation with KOH under various activation temperatures and chemical ratios of KOH
to semi-carbonized cotton stalks (CCS). The surface area, total pore volume and average pore diameter were evaluated by N2-
adsorption at 77 K. The surface morphology and oxygen functional groups were determined by SEM and FTIR, respectively.
Batch equilibrium and kinetic studies were carried out by using a basic dye, methylene blue as a probe molecule to evaluate the
adsorption capacity and mechanism over the produced carbons. The obtained activated carbon (CCS-1K800) exhibited highly
microporous structure with high surface area of 950 m2/g, total pore volume of 0.423 cm3/g and average pore diameter of 17.8 A.
The isotherm data fitted well to the Langmuir isotherm with monolayer adsorption capacity of 222 mg/g for CCS-1K800. The
kinetic data obtained at different concentrations were analyzed using a pseudo-first-order, pseudo-second-order and intraparticle
diffusion equations. The pseudo-second-order model fitted better for kinetic removal of MB dye. The results indicate that such
laboratory carbons could be employed as low cost alternative to commercial carbons in wastewater treatment.
영어초록
Four activated carbons were produced by two-stage process as followings; semi-carbonization of indigenous biomass waste,i.e. cotton stalks, followed by chemical activation with KOH under various activation temperatures and chemical ratios of KOHto semi-carbonized cotton stalks (CCS). The surface area, total pore volume and average pore diameter were evaluated by N2-adsorption at 77 K. The surface morphology and oxygen functional groups were determined by SEM and FTIR, respectively.Batch equilibrium and kinetic studies were carried out by using a basic dye, methylene blue as a probe molecule to evaluate theadsorption capacity and mechanism over the produced carbons. The obtained activated carbon (CCS-1K800) exhibited highlymicroporous structure with high surface area of 950 m2/g, total pore volume of 0.423 cm3/g and average pore diameter of 17.8 A.The isotherm data fitted well to the Langmuir isotherm with monolayer adsorption capacity of 222 mg/g for CCS-1K800. Thekinetic data obtained at different concentrations were analyzed using a pseudo-first-order, pseudo-second-order and intraparticlediffusion equations. The pseudo-second-order model fitted better for kinetic removal of MB dye. The results indicate that suchlaboratory carbons could be employed as low cost alternative to commercial carbons in wastewater treatment.