| The hydroformylation of olefins represents one of the largest homogeneously catalyzed reactions in industry.Formed aldehydes are valued final products which have been applied for synthesis bulk chemicals like alcohols,esters,and amines.Although modified Rh-based catalysts possess excellent catalytic effect in homogeneous hydroformylation but suffering from the problems of separation,recycling the catalysts and successive industry operation.Water and organic solvents are most common reaction media applied in the majority of homogeneous hydroformylation.Due to the limited solubility of long chain olefins in water,the application of the traditional water-organic biphase catalysis systems have been restricted.In ordered to overcome the drawbacks investigations are focused on developing the new biphasic catalysts and heterogenization of homogeneous catalysts,the problems of the leaching of active metal and the low regioninal-selectivity still exist in the catalysis systems.Therefor synthesis of novel immobilization Rh-based catalysts for hydroformylation has the practical significance.In this thesis,three kinds of polymers,including phenolic resin,resorcinol resin and phosphorus modified phenolic resin had been synthesized and characterized using the analytical equipments such as N2 adsorption,FT-IR,XRD and XPS spectra.The results of nitrogen sorption analysis,FT-TR,XRD,and XPS showed that the total surface area and pore volume decreased after the supporter was modified and loaded with Rh(CO)2(acac)indicating that the active component has dispersed on the external surface and mesoporous.The XPS results demonstrated the chemical interaction between Rh species and organic phosphine ligand.The factors such as the supporters,the amounts of active metal,the reaction temperature and pressure had been investigated in the hydroformylation 1-octene.It showed in the experiments that,when the chlorodiphenylphosphine modified phenolic resin was used as the supporter,the imbolized Rh complexes was active catalyst in the 1-octene hydroformylation with the optimizing conditions realized at 60 ?,3 MPa syngas pressure and 2%metal loading after reaction 4 h.The catalytic system provided 98.3%aldehydes selectivity and n-nonanal/iso-nonanal reach to 1.9.The chlorodiphenylphosphine modified resorcinol resin was then used as supporter to prepare immobilized Rh catalyst(RS-Rh).The Rh-based catalyst was applied in hydroformylation of 1-octene,giving 71.2%conversion,42.3%chemoselectivity and modest linear/branched(2.6)under pressures of Pco = PH2= 3 MPa and at a temperature of 60 ?,after 4 hours reraction.After recycle for three times,the conversion declined sharply for the leaching of metal and the regioselectivity still remained.Inorganic phosphorus doping resin was then uheterogeneous sed as supporter and post-modified with chlorodiphenylphosphine to synthesis catalyst(FDU-15P-Rh).The FDU-15P-Rh was evaluated in hydoformylation of 1-octene at pressures of Pco = PH2=3MPa and at a temperature of 60 ?,affording 51%conversion,54%aldehyde selectivity and a linear/branched aldehyde ratio of 2.6 after 4 hours.In order to analyze the coordination ability of alkylphosphorus,inorganic phosphorus doping resin was directly used as supporter to immobilize Rh.In the hydroformy;ation of 1-octene under the same reaction conditions,achieving 38.3%conversion,23.2%aldehyde selectivity and a linear/branched aldehyde ratio of 2.7.In the recycling experiment,the FDU-15-Rh showed lower leaching and execellent stsbility than the other two kinds of catalysts after being recycle for three times.In the hydroformylation of 1-octene,RS-Rh and FDU-15P-Rh catalysts retained high regioselectivity than FDU-15-Rh,but the catalytic stability was yet to be improved. |
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