PATENT

3798.  VAN’T SPIJKER, P., AND HART, M.  (Shell Development Co.).  Synthesis of Carbinols.  United States Patent 2,581,988, Jan. 8, 1952; appl. filed Oct. 17, 1950, Serial No. 190,523; 1 claim (Cl. 260-638).

In the multistep Oxo process the olefinic reactant is reacted with CO and H2 in a 1^st step to give a product consisting largely of aldehydic products, with minor amounts of higher boiling oxygenated products (thick oil), carbinol, unreacted olefin, diluents, soluble Co compounds and suspended catalyst.  The product from this so-called carbonylation step contains dissolved Co as impurity; therefore, it is passed through a decobalting step wherein the soluble Co compounds are decomposed to form insoluble metallic Co.  The product including the suspended Co, is finally passed through a hydrogenation stage wherein the aldehydic intermediate products are converted to carbinols.  The catalyst for both stages, Co on “Celite”, gradually loses its effectiveness, and it is recycled after separation from the product back to the carbonylation stage where it is replenished by addition of about 4% of fresh catalyst as a slurry in the olefin feed.  It is now found that better results are obtained in maintaining the activity of the catalyst if the fresh catalyst used for replenishment is added at a point just preceding the hydrogenation stage.  The yield of product is improved, and there is less formation of the undesired thick oil. of the process are presented in a flowsheet.