Critical Solution Temperature Of The Thermostat Phosphine Ligands In The Two-phase Hydroformylation

In this dissertation, the solubility of nonionic tensioactive phosphine ligand P[p-C6H4O(CH2CH2O)nH]3 (PETPP) is studied in different nonpolar and aprotic solvents. It was found that PETPP possess distinct Critical Solution Temperature (CST) in toluene and benzene. Toluene was the favorable choice as a solvent for separating homogeneous catalyst. A novel concept (Thermoregulated Phase Separable Catalysis, TPSC) based upon CST of PETPP for separating catalyst from the reaction mixture is confirmed.Furthermore, the catalytic properties and recycling efficiency of PETPP/Rh complex were investigated extensively in toluene, with focus on the hydroformylation of higher olefms. The experimental data indicated successful hydroformylation of Ce-u straight chain higher olefms under TPSC system. Under the optimum condition, the conversion and yield for aldehyde of 1-decene reached 98.7% and 96.0%, respectively. After 10 times recycling of the catalyst, the total loss of rhodium was only 3.44% mass percent, and the conversion of 1-decene was more than 94.9%. With the addition of investigation, the loss of rhodium could decrease by 50% compared with normal PETPP and pure toluene, as PETPP of narrow molecular distribution and mixed solvent are used. It indicated that TPSC system was featured by homogeneous catalysis coupled with heterogeneous separation.