Hydrophobic Modification Experiment and Characterization of FDU-15 with Different Pore Diameter

Abstract

Three ordered mesoporous carbon materials FDU-15 with different pore diameter were used.The pore size of FDU-15 can be achieved by changing the temperature and calcination atmosphere during template removal calcination.There are more polar functional groups on the inner and outer surfaces of FDU-15 pores. As a highly hydrophilic group, hydroxyl will make FDU-15 adsorb more water molecules. In practical application, water molecules and PAHs (polycyclic aromatic hydrocarbons) will produce competitive adsorption. At the same time, PAHs are mainly non-polar compounds, so non-polar adsorbents are more conducive to the adsorption of PAHs.In conclusion, the nonpolar functional groups on the surface of FDU-15 will reduce the adsorption of PAHs, which is also caused by the poor thermal and hydrothermal stability of FDU-15 material, which limits the application of FDU-15.Therefore, hydrophobic modification of FDU-15 can reduce the number of hydroxyl functional groups on its surface, adjust the surface hydrophobicity, enhance the hydrothermal stability and improve the adsorption performance of FDU-15 for PAHs. The silylation hydrophobic modification of adsorbent is studied, and the FDU-15 with different pore diameter is hydrophobically modified. It is expected to obtain a modified FDU-15 with the best pore size by comparing its adsorption isotherm, which can be put into practical use. The hydrophobic modification in this study adopts post transplantation method, and the modified samples are characterized by FT-IR to test the modification effect.