Process to separate a rhodium/phosphite ligand complex and free phosphite ligand complex from a hydroformylation mixture

摘要

Process to separate a rhodium/phosphite ligand complex and free phosphite ligand from a hydroformylation mixture also containing high boiling hydroformylation compounds by contacting said mixture with a polymeric membrane, wherein said mixture is diluted with at least one diluent compound having a solubility parameter such that the absolute difference in relation to the solubiltity parameter of the polymeric membrane lies between 0 and 400{square root}{square root over (KJ/m³)} and the ratio of the molar volume of the phosphite ligand and said diluent compound is 1.5, to such an extent that the amount of high boiling compounds in said mixture is 50 wt. % (relative to the total amount of the mixture) and the amount of compounds with a molecular weight of between x 200 is 20 wt. % (relative to the total amount of the mixture) whereby x is the cut-off of the membrane (g/mole).