Process for the hydroformylation of sulfur-containing thermally cracked

Abstract

A catalytic process for the hydroformylation of olefinic, sulfur containing thermally cracked petroleum streams to produce aldehydes and/or alcohols is disclosed. The catalysts are homogeneous transition metal carbonyl complexes. Especially preferred catalysts for low and medium pressure hydroformylation are cobalt and rhodium carbonyl hydride complexes in which some of the carbonyl ligands have been replaced by trivalent phosphorus ligands. In a preferred high pressure hydroformylation, the sulfur-containing naphtha and gas oil distillate feeds are produced from vacuum residue by high temperature thermal cracking. Such feeds contain more than 20% olefins with 1-n-olefins as the single major types. These olefin components are hydroformylated in the presence of a cobalt carbonyl complex to produce a novel type of semilinear aldehyde and/or alcohol product containing an average of less than one alkyl branch per molecule. The alcohols are converted to dialkyl phthalates and other esters having a unique balance of plasticizer properties. They are also useful for producing novel surfactants, particularly ethoxylated derivatives. For the preparation of products containing minimal concentrations of sulfur compounds, narrow distillate fractions of thermally cracked residua are preferred. In the C.sub.6 to C.sub.11 carbon range, single carbon fractions of sharply reduced aromatic hydrocarbon and thiophenic sulfur content can be obtained. These fractions of increased linear olefin content can be advantageously used as hydroformylation feeds in the derivation of low sulfur containing alcohols and related products of increased linearity.