Catalytic Performance And Modification Of Activated Carbon Surface

With the development of green chemistry, solid catalysts obtain more attention due to its advantages such as reusable, non-corrosive and easy separation from mixture. In this paper, the activated carbon was modified by organic amine agents after oxidation. The result shows that more amino function introduce onto the surface via amide modification.Firstly, the activated carbon was oxidized by using different concentration nitric acid and hydrogen peroxide. The surface properties of oxidized carbons were characterized by Boehm titrations, surface area and porosity measure, FT-IR and TG-DTG. It is found that the oxidized carbon can be used as a acid catalyst in addition reaction of cyclohexene oxide and methanol, the conversion of cyclohexene oxide was up to 97.83% after 5 h when reaction temperature is 40℃.Secondly, the oxidized carbon was treated with thionylchlorid and then ethylenediamine to introduce surface-bound amino function onto the surface via amide modification. The surface properties of aminated carbons were characterized by Boehm titrations, surface area and porosity measure, FT-IR and TG-DTG and the probably mechanism of amination was investigated. It is found that the aminated carbon can be used as a catalyst in Aldol condensation of acetone, which performance was compared with strongly basic macroporous ion exchange resin D201 . Thirdly, The carbon which oxidized by nitric acid was directly aminated with ethylenediamine, then the aminated carbon was used as a catalyst in Michael condensation reaction of croton aldehyde and nitromethane, the effects of amount of catalyst, reaction temperature, reaction time and molar ratio of reactant were investigated. Based on the results the conversion of croton aldehyde was up to 97.07% after 20 h when reaction temperature is 100℃and the molar ratio of croton aldehyde and nitromethane is 1/3.Finally, the performance of aminated carbon which aminated from a single-step reaction after oxidized with hydrogen peroxide as a catalyst in Michael condensation reaction of citral and nitromethane was studied. It was found that when reaction temperature is 100℃, the mass of catalyst is 15% of the reactant’s and the molar ratio of citral and nitromethane is 1/9, after 4 h the conversion of citral was up to 100%.