Study On The Synthesis Of MOF Catalyst By Bipyridyl Platinum Complex

Metal organic frameworks(MOFs)is mostly composed of oxygen,nitrogen and other multi-tooth organic ligands and inorganic metal ions through the coordination of self-assembly formed an ordered network-like porous structural materials.It has a large surface area,high porosity,and diverse structure and so on.The pore size can also be adjusted by using different ligands as needed.These features make MOFs materials widely used by researchers in the fields of gas separation and storage,catalysis,drug release and fluorescent materials.In the field of catalysis,MOFs are also often used as carriers to achieve the catalyst from homogeneous to heterogeneous transition,making the catalyst to retain the catalytic activity can be recycled many time.The use of nitrogen-containing ligand synthesis of MOFs due to the presence of nitrogen can make the carrier has a unique electronic properties,improve the metal-carrier interaction.In this paper,we mainly use UF-67 materials in MOFs materials for experimental study.The UIO-67 material was synthesized using 2,2'-bipyridine-5,5'-dicarboxylic acid(bpydc)and 4,4'-biphenyl dicarboxylic acid(bpdc)as ligands.By modifying the ligands of synthetic UIO-67,a new type of high efficiency MOFs catalyst which can be used in industrial catalysis was designed and synthesized,and the intrinsic relationship between the structural properties and catalytic performance of the catalysts was studied.The main contents of the thesis are as follows:1.Based on the original synthesis of UIO-67,the molar ratio of the two ligands was first adjusted to the molar ratio of the zirconium source.The molar ratio of zirconium to ligand is 1:1,and the molar ratio between the two ligands is 1:1.The optimum conditions for synthesizing our materials are as follows.The ligand 2,2'-bipyridyl-5,5'-dicarboxylic acid(bpydc)was then reacted with [Pt(Ph)2(Et2S)]2 in anhydrous ether under nitrogen to the ligand Pt(Ph)2@bpydc.The UIO-67 catalyst containing platinum nanoparticles was synthesized by in-situ one-step reduction of zirconium source and two ligands in DMF solvent and 120 oC with nitrogen protection.By adjusting the molar ratio of Pt(Ph)2@bpydc and bpdc to 1:9,the best morphology of the catalyst was obtained.The catalyst was applied to catalyze the reaction of 5-hydroxymethylfurfural to form 2,5-dihydroxymethylfuran.The conversion of the reactants reached 99.5% and the final yield was over 90%,which indicated that the application of the catalyst had certain prospects.2.In order to solve the drawbacks of using the Friedel-Crafts method for the preparation of alkylaromatics in the industry(the difficulty of catalyst recovery,the resulting product is not a disadvantage that a single product contains multiple by-products).We have made reference to the University of Virginia T.Brent.Gunnoe,using Pt-bipyridine complex as a catalyst for the preparation of alkylaryl hydrocarbons,[Pt(Ph)2(Et2S)]2 onto UIO-67 to prepare UIO-Pt(Ph)2 catalyst.First,the ligand 2,2'-bipyridine-5,5'-dicarboxylic acid(bpydc)was modified in the previous part to obtain the ligand Pt(Ph)2@bpydc containing the platinum metal complex.Then,DMSO solvent was used to replace the DMF solvent to carry out the synthesis catalyst.Pt(Ph)2@UIO-67 was synthesized by one-step method in DMSO solution.By adjusting the type of acid(benzoic acid and acetic acid)and the concentration(40 times-70 times the molar amount of zirconium source),acetic acid was used as the auxiliary acid,40 times the concentration of the catalyst for the synthesis of the required conditions.In this part,we also tried to synthesize the catalyst using post-grafting synthesis,first using bpdc and bpydc in the DMF solvent at 120 oC synthesis of UIO-67,and then with the [Pt(Ph)2(Et2S)]2 in anhydrous diethyl erher reaction under nitrogen protection,get a Pt(Ph)2@UIO-67.The structure was characterized by structural morphology.