Hydroformylation of olefins

A process for producing higher alcohols from an olefinic feedstock comprising olefins containing from 6 to 12 carbon atoms which comprise:

• (a) hydroformylating said olefinic feedstock with synthesis gas in the presence of a cobalt-containing hydroformylation catalyst to form a hydroformylation product mixture containing higher aldehydes and higher alcohols having a carbon number which is one carbon atom greater than said olefinic feedstock, unreacted olefinic feedstock and secondary reactions products;
• (b) treating said hydroformylation product mixture to remove said hydroformylation catalyst therefrom and to form a decobalted hydroformylation product mixture;
• (c) hydrogenating said decobalted hydroformylation product mixture to convert said higher aldehydes to additional amounts of said higher alcohols;
• (d) distilling the higher alcohol-containing hydrogenation product mixture formed in step (c) to separate (i) a lower boiling light oxo fraction and (ii) said higher alcohols from (iii) a higher boiling heavy oxo fraction;
• (e) subjecting the heavy oxo fraction to catalytic steam cracking at a temperature of from 260.degree. to 380.degree. C. in the presence of a cracking catalyst selected from the group consisting of active metal oxides and pseudo-metal oxides, to form a cracked heavy oxo fraction mixture comprising a major proportion of higher alcohol and higher aldehyde, and a minor proportion of olefin, saturated hydrocarbon and uncracked heavy oxo fraction residue;
• and (f) recycling said cracked heavy oxo fraction mixture to the hydroformylation or hydrogenation stage of the process.