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Preparation And Characterization Of Catalyst PD@PAF-1and Its Application In Suzuki Cross-Coupling Reaction

Posted on:2014-05-30Degree:MasterType:Thesis
Country:ChinaCandidate:C H ZhouFull Text:PDF
GTID:2251330398483475Subject:Chemical Engineering and Technology
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Metal organic frameworks developed recently is a kind of porous material. The research of this porous material in adsorption, gas storage and separation has been very mature, but the application of this material in catalysis is still in the stage of development. Metal organic frameworks has high specific surface area which provided it conditions to catalyze chemical reactions, but at the same time, some problems arose, such as the low stability to water of metal organic frameworks, which limited the application of metal organic frameworks in catalysis. In actual industrial reactions, both high specific surface area and appropriate pore structure of the carrier of catalyst is required, and good physical and chemical stability and thermal stability is also important. We compared the comprehensive performance of several kinds of porous materials, and then selected a material as a carrier for the noble metal catalyst. We prepared catalyst by microwave and dipping methods, characterized the properties of the resulting catalyst, and at the same time selected the Suzuki cross-coupling reaction to verify catalytic effect. The main contents of our experiment are as follows:1.We synthesized five different porous materials:Fe-MIL-101-NH2IRMOF-3、ZIF-8、ZIF-67、PAF-1, and characterized them with XRD、BET and stability test. By contrast, we concluded that PAF-1not only has high specific surface area, but also showed better stability in water、strong acid and strong alkali. So we choose PAF-1as the carrier of metal catalyst.2.We prepared catalyst Pd@PAF-1by microwave and dipping methods, and characterized the catalyst with XRD、SEM、TEM、HRTEM、FT-IR and total analysis. Relative to traditional dipping method, the metal Pd nanoparticles prepared by microwave method dispersed evenly, showed no aggregation phenomenon, particle size distribution ranged from2.5nm to5nm, and average particle size was3.91nm. In addition, we used this two catalysts in the coupling reaction between1-bromo-4-nitrobenzene and phenylboronic acid. The catalytic yield of catalyst prepared by dipping method was77.54%, while the yield of catalyst prepared by microwave method was89.96%which was obviously superior to the traditional dipping method.3.We prepared catalysts with different amount of Pd by microwave method, and used them in coupling reactions. By this, we concluded that the best loading amount of Pd was5%and the best amount of catalyst used was0.1mol%which was greatly reduced. Then we used this catalyst between some different aryl halide and phenylboronic acid, and the yield was85%-96%.
Keywords/Search Tags:porous aromatic polymers, metal palladium, catalyst, suzukicross-coupling reaction
PDF Full Text Request
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