Study on the effect of acidic-basic modification on the surface groups and pore structure of activated carbon

• 1、School of Environmental Science & Engineering, Huazhong University of Science and Technology, Wuhan 430074

Abstract：A series of special activated carbon were prepared by modifying the commercially available spherical activated carbon(SAC) through HCl,H2SO4,HNO3,NH3oH2O and NaOH, respectively. SAC before and after modification were characterized by Boemh titration,N2 adsorption,Roman and DRIFTS methods.Effect of different modification methods on surface functional groups and pore structure of activated carbon were researched. The results showed that surface functional groups and the physical and chemical properties of activated carbon had greatly changed before and after modification.With the concentrations of HCl, H2SO4 and HNO3 increasing, the content of carboxylic acid and phenolic hydroxyl groups of activated carbon increased.While,activated carbon modified by HNO3 had the highest acidic functional groups content.Although the increase of basic groups content modified by NH3oH2O was less, basic groups content modified by NaOH were beyond 50%,showing the great performance of the base modification.Besides,the specific surface area and pore size had changes with different degree before and after modification,while that was little affected by HNO3 or NaOH modification.The latter could give some support on the correlation study between the different surface functional groups and its gas selective absorption under the conditions of the same or similar pore structure,and thus has a great potential of real-world applications.

Keywords： spherical activated carbon(SAC) acidic-basic modification surface functional groups pore structure