Synthesis Of Hierarchically Porous Materials With Phenolic Resin As A Hard Template

The paper has been carried out to synthesize hierarchically porous structure materials and then to prepare mesoporous catalytic materials.by modifying materials.with heteroatoms.In this paper, hierarchiacally porous materials are referred to those materials containing both micropore and mesoporoe. Hierarchiacally porous materials conbine the advantages of microporous and mesoporous materials,that they not only have high thermal and hydrothermal stability,Stronger acidity, but also have larger outer surface area and higher diffusional rate within the crystal,which make them have more potential applications in the actual production and living.In the first part, we try to prepare mesoporous MFI zellite by using phenolic prepolymer as a hard template, non-ionic triblock copolymer surfactant Pluronic F127 and tetrapropylammonium hydroxide (TPAOH) as soft template.Firsty,we prepared phenolic prepolymer with phenol and formaldehyde in the condition of alkaline,followed by forming gels in ethanol with phenolic pre-polymer, block copolymer Pluronic F127, tetrapropylammonium hydroxide and silica source (TEOS) and then the obtained powder was crystallized in PTFE autoclave at 170℃for 2 days,and finally calcined at 600 degree to remove the organic hard and soft template to obtaine the mesoporous MFI zelite. In the synthesis process,we have studied the following conditions that influenced synthesis of Mes-MFI(1) The temperature of pre-crystallization. We found that the temperature of pre-crystallization has a great effect on synthesis of meso-MFI.The sample pre-crystallized at 80 degrees was clearly not smooth, with the existence of mesopore, while the sample treated at 20 degrees was the same as the conventional MFI without the existence of mesopore.(2) The presence of Pluronic F127.We found that the addition of F127 was beneficial to the formation of mesopore.(3) The amount of TPAOH. We Found that as the amount of the TPAOH increased,the sample obtained was more uniform, and the primary particles were smaller.(4) The thermopolymerizaltion temperature.The results showed that the thermalpolymerization temperature had great effect on the crystallization of MFI zelite by decomposing part template of TPAOH. (5) The amount of phenolic prepolymer.The results showed that a certain amount of resol acting as hard template was beneficial to the formation of mesopore.but when the mass ratio of Resol:TEOS was more than 3.5:5.2, the excessive resol would inhibit the crystallization of MFI zeoliteIn the second part, we modified ordered mesoporous polymer-silica nanocomposites and mesoporous carbon-silica nanocomposites with the metal Ti, Sn, Zr atoms. We prepared Ordered mesoporous polymer-silica nanocomposites and Carbon-Silica Nanocomposites referring to the method of Zhao'Triconstituent Co-assembly, But we added metal atoms of Ti or Sn or Zr that haveing Catalytic activity to prepare mesoporous catalytic materials in the synthetic system, and finally We characterized the synthesized materials by XRD, SEM, UV, BET.