Synthesis And Characteristic Of Core-shell Structure Zeolite@MOFs And Zeolite@COFs Composite

Since the rapid development of ordered porous materials in the last century,many kinds of ordered porous materials have been synthesized and applied by chemists.Each kind of material has its own properties and characteristics.It is feasible to synthesize hybrid materials to combine these excellent properties.The exploration of new hybrid porous materials have many unique properties and potential applications,such as separation and adsorption materials.Zeolites,MOFs and COFs are indispensable materials in ordered porous materials.Aluminosilicate zeolite s have been widely used in the adsorption and separation of gas,catalytic cracking of petroleum and fine chemical industry.MOFs are composed of metal nodes and organic ligands.They have uniform and controllable microporous structure,large specific surface area and controllable chemical properties.As a subclass of MOFs,ZIF-8 has good thermal stability and chemical stability.It has been commercially produced due to its great potential in gas separation and storage.COFs are composed of organic ligands by reversible covalent bonds.They have excellent properties in semiconductors and optoelectronic devices,selective separation and many other aspects.It is expected that combined Zeolite with MOFs or COFs to obtained composites can broaden the application scope of these materials.The main research work of this thesis includes the following two parts:1.Synthesis and characterization of LTA@ZIF-8 core-shell structure material.Due to the different structures and characteristics of zeolite A and ZIF-8,we expect to combine the advantages of them and get more attctive properties in practic al applications.We synthesized zeolite A and fully coverd a layer ZIF-8 crystals on the zeolite A.The core shell structure of LTA@ZIF-8 have potential in CO₂/CH₄adsorption and separation.2.Synthesis and characterization of self supported zeolite beta@?SERP-COF2core shell structure.Because COFs are completely connected by organic ligands,most COFs materials are natural hydrophobic,e xcept for boric acid ester COFs which is easy to hydrolyze.Aluminosilicate zeolites are hydrophilic.But hydrophilicity is not conducive to the practical application of zeolite.So it is great significance to synthesis core shell structure of Zeolite@COFs.Firstly,the self supporting zeolite beta beads were synthesized by the chloride anion exchange resin at the sacrifice template.And then the IISERP-COF2 material was sucessfully coated on the beads.The composite of zeolite beta@IISERP-COF2 were placed for a week under the condition of 79%air humidity.The weight of water vapor in the air adsorbed only accounted for 1.6%of their weight.Compared with the 10.4%water absorption of the self supporting zeolite beta beads under the same conditions,the hydrophobicity of the composite beads was greatly improved.