Dissertation | Technische Universität Carolo-Wilhelmina zu Braunschweig
Gas-liquid-liquid systems, in which a gas is absorbed into an oil-water emulsion with or without chemical reaction, are of scientific, technical and commercial importance due to their wide industrial application.
Through the development of the aqueous biphasic technique in homogeneous catalysis, gasliquid-liquid systems have gained increasing attention in various chemical processes, e.g. hydroformylation, carbonylation, hydrogenation and oligomerization (Cornils, 1999). This aqueous biphasic technique involves using water-soluble ligands to solubilize the metal complex catalyst in an aqueous phase, which is easily separated from reactants and reaction products by decantation. Hydroformylation of propene to n-butyraldehyde is a typical example for important industrial applications of gas-liquid-liquid reaction systems. In this process, the reactive gas mixture of carbon monoxide, hydrogen and propylene is converted to n-butyraldehyde in an aqueous solution of rhodium catalyst (Cents et al., 2004). Three different phases therefore exist in the reactor: the gas phase containing CO, H2, and propylene; the aqueous catalyst phase (water phase); and the dispersed organic butyraldehyde phase (oil phase).