Abstract: A method for the recovery of a Group VIII noble metal solid complex is described, which comprises bringing an organic compound-containing solution containing therein a Group VIII noble metal complex having a tertiary organophosphorous compound as a ligand into contact with an oxidizing agent in the presence of a free tertiary organophosphorous compound, an organic polar solvent, water, and a basic substance to preciptate a solid complex of the Group VIII noble metal, and a separating the precipitated Group VIII noble metal solid complex from the solution.

Abstract: A process for hydroformylation of olefins is described which comprises a step of reacting olefins with carbon monoxide and hydrogen in the presence of a Group VIII noble metal-triarylphosphine complex catalyst, an excess amount of triarylphosphine, a reaction solvent, and organic high boiling point by-products, taking out the produced aldehyde by separating from the resulted hydroformylation reaction product, and thereafter circulating the residual liquid containing the catalyst and the organic high boiling point by-products to the reaction system as a circulating catalyst liquid, wherein the improvement comprises withdrawing at least a part of said circulating catalyst liquid as an extracted catalyst liquid, distilling off at least a part of the organic high boiling point by-products by steam distillation of said extracted catalyst liquid, and recirculating the bottoms of the steam distillation tower to the hydroformylation reaction step.

Abstract: A process for the hydroformylation of an olefin, comprising reacting the olefin with carbon monoxide and hydrogen in a catalyst liquid containing a Group VIII noble metal-triarylphosphine complex catalyst, excess triarylphosphine and a reaction solvent to form an aldehyde, characterized by withdrawing a part of the catalyst liquid as a spent catalyst liquid, subjecting the spent catalyst liquid to crystallization, recovering crystallized triarylphosphine from the spent catalyst liquid, and recirculating the recovered triarylphosphine into the reaction zone.

Abstract: Glycol monoethers are produced in high yields by reacting an acetal with carbon monoxide and hydrogen in the presence of a catalyst comprising a cobalt compound and a trivalent organic phosphorus compound or a bidentate chelate ligand containing nitrogen or oxygen. An aldehyde or a compound capable or releasing an aldehyde under reaction conditions and an alcohol can be used instead of the acetal.