Abstract: Acetals are formed from an aldehyde hydrogenation product mixture comprising alcohols and at most 2% of alde-hydes and the product is distilled to yield purified alcohols and a second stream containing acetals and/or unsaturated ethers.

Abstract: In a hydroformylation reaction, the circulation and recovery of cobalt carbonyl in a cobalt catalyst cycle using carbonylate as an intermediate and acidification thereof, is improved by supplying an aqueous sulfuric acid solution containing less than 16% wt of sulfuric acid to the carbonylate to control sulfuric acid concentration in the carbonylate/acid mixture, before accounting for any acid consuming reaction, to a value of from 2% to 10% by weight. Single step and multistage liquid/liquid extraction techniques as well as vapor/liquid extraction techniques followed by the absorption of cobalt from the vapor in an organic liquid both benefit from this improvement.

Abstract: The invention relates to improvements in internal loop reactors. The reactor of the invention is characterized by a plurality of cooling tubes which form the annulus between the riser and the downcomer path of said internal loop reactor. The reactor also provides improvements in hydroformylation reactions using the improved reactor.

Abstract: In a hydroformylation reaction, the circulation and recovery of cobalt carbonyl in a cobalt catalyst cycle using carbonylate as an intermediate and acidification thereof, is improved by supplying an aqueous sulfuric acid solution containing less than 16% wt of sulfuric acid to the carbonylate to control sulfuric acid concentration in the carbonylate/acid mixture, before accounting for any acid consuming reaction, to a value of from 2% to 10% by weight. Single step and multistage liquid/liquid extraction techniques as well as vapour/liquid extraction techniques followed by the absorption of cobalt from the vapour in an organic liquid both benefit from this improvement.

Abstract: Acetals are formed from an aldehyde hydrogenation product mixture comprising alcohols and at most 2% of alde-hydes and the product is distilled to yield purified alcohols and a second stream containing acetals and/or unsaturated ethers.

Abstract: The invention relates to improvements in internal loop reactors. The reactor of the invention is characterized by a plurality of cooling tubes which form the annulus between the riser and the downcomer path of said internal loop reactor. The reactor also provides improvements in hydroformylation reactions using the improved reactor.

Abstract: The invention relates to improvements in internal loop reactors. The reactor of the invention is characterized by a plurality of cooling tubes which form the annulus between the riser and the downcomer path of said internal loop reactor. The reactor also provides improvements in hydroformylation reactions using the improved reactor.

Abstract: The gas cycle in a high pressure hydroformylation reaction using a series of at least two reactors is controlled to optimise yield, conversion and selectivity and to control reaction temperature. The control is achieved through balancing fresh gases and recycle gases in each of the reactors and as an optional feature the use of hydrogen off gases from the downstream hydrogenation used in the conversion of the hydroformylation reaction product to product alcohols.

Abstract: The invention relates to improvements in internal loop reactors. The reactor of the invention is characterized by a plurality of cooling tubes which form the annulus between the riser and the downcomer path of said internal loop reactor. The reactor also provides improvements in hydroformylation reactions using the improved reactor.

Abstract: An exothermic chemical reaction, for example, hydroformylation, is carried out in a series of loop reactors. Fresh reactant feed is supplied not only to the first reactor in the series but also to the second reactor, thereby achieving improved overall throughput while maintaining a stable temperature in at least the first reactor.