Rhodium Catalyst In The Methanol Carbonylation Reaction Structure And Properties Of,

This thesis is consist of five parts.In the first part of this thesis, a few kinds of minor organic molecular rhodium complexes containing free donors, which imitate copolymer rhodium complexes, had been synthesized, by using IR spectrum and photoelectric spectrum, we studied the formation of rhodium complexes, the intramolecular substitution reaction as well as the relationship between its stability and intramolecular substitution reaction. On the basis of analyses, we drew conclusions as follow.1. The rhodium complexes with uncoordinated donors can take place the intramolecular substitution reaction, which is reversible. By intramolecular substitution reaction, rhodium active center is away from decomposition of catalyst in the condition of heating, oxygen without the protection of CO.2. In the process of catalytic reaction, rhodium complexes with free donors have similar activity as those without free donors. However, their stability was largely improved due to the existence of free donor atoms, which can take place intramolecular substitution reaction.3.The intramolecular substitution reaction is the theoretic foundation of the high stability of the novel copolymer rhodium complexes which was founded by our group. It plays an important role of guidance in the design and synthesis of this kind of complexes. In the second part of this thesis, A novel macromolecule polymer rhodium complexes have been studied on. On the basis of data of IR and XPS, the characteristic of coordinated structure have been found about this kind of copolymer rhodium complexes. And we discussed the influence of the variation of the ratio in monomer on the catalytic activity. With the increase of content of dimethyl maleate in the ligand, the catalytic activity of corresponding complexes increased.In the third part of this thesis, the mechanism of catalytic carbonylation about copolymer rhodium complexes have been researched. And we draw conclusions as follows:1. In the first course of the catalytic carbonylation circulation, CH3I is added to rhodium complex and oxidizes it. Secondly, CO is inserted and coordinated with copolymer rhodium complex and the CH3- is transferred. At last, CH3COI departs from it. So the catalytic circulation is finished.2. In the circulation of catalyzing carbonylation, the N-Rh coordinated bond kept stable due to the stronger coordinated action between Rh and N on pyridine circle, and it enable tosolve the loss of Rh in the course of carbonylation reaction. When CH3I is added to rhodiumcomplex and oxidizes it, the O-Rh coordinated bond is easy to dissociate attributed to theirweaker coordinated action. So the rhodium complex will maintain its high catalytic activity.And the dissociated O and Rh will coordinate with each other again in the end of catalyzingcirculation.In the forth part of this thesis , the influence of carbonylation reaction condition on thecatalytic activity about copolymer rhodium complex were studied here, and we get initial resultsas follows:1. The more [Rh] is used, the faster carbonylation reaction speed will be improved.2. In a certain range of concentration, carbonylation reaction speed up followed by the addition of [CH3I].3. The partial pressure of CO has nothing to do with the catalyzing activity about copolymer rhodium complex if it maintains above 1.4 MPa in reaction system.4. The thinner [CH3OH] is, the shorter the top reaction activity reaches. But [CH3OH] has loose relation to the catalyzing activity about copolymer rhodium complex when it is kept beyond 0.5 mol/L.5. Additional polar agent, such as acetic acid, will help to improve the catalytic activity of copolymer rhodium complex.6. Catalyzing activity of copolymer rhodium complex raises with the rising temperature. And it maintains its activity even if the reaction temperature climbs up beyond 190 ℃.In the fifth part of this thesis, the bimetallic complexes have been studied on. The transitional metal Cu, Ni, Co and Ru were coordinated with the same rhodium complexes to give bimetallic complexes. On the basis of thei...