Summary: | 碩士 === 國立聯合大學 === 化學工程學系碩士班 === 97 === Activated carbon was prepared from Acacia confusa by ZnCl2-activation in this work. Two carbon series were prepared with different activated temperature (400, 450, 500, and 550℃) at ZnCl2/raw material ratio 1.75, and ZnCl2/raw material ratio (0.75, 1.25, 1.75, and 2.25) at 500℃. It was obtained that activated carbon derived from ZnCl2/raw material ratio 1.75 (at 500℃, 1h), has the highest BET surface area of 2,009 m2/g and 38.8% of yield. Physical properties of activated carbon include specific surface area and pore volume measured by the method of N2 adsorption/desorption at 77K, and the scanning electron microscope (SEM) observation as well as the chemical properties, namely elemental analysis and temperature programmed desorption (TPD), and thermo gravimetric analysis (TGA) were measured. The adsorption kinetics and equilibrium isotherms of dyes (Methylene blue, Acid blue 74, Bismarck brown Y) and 4-chlorophenol from water at 30℃ on the activated carbons were studied. Two simplified models including the Elovich equation and intraparticle diffusion model were used to test the adsorption kinetic; it was suitably described by the Elovich equation. Two simplified models including the Langmuir and Freundlich isotherm equation were selected to follow the adsorption process; the adsorption equilibrium isotherm was in agreement with the Langmuir equation. The monolayer coverage (qmon) of MB, AB74, BBY, and 4-CP for ZAC175500 activated carbon of 494, 366, 439, and 410 g/kg, respectively; it revealed their good adsorption capability for dyes and 4-CP. This study proved that activated carbon prepared in this work had high BET surface area, high yield and good adsorption capability, had application potential.
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