Increased catalyst life in the hybroge- nation of hydroxyaldehydes to poly- gls

Claim 1

IN A PROCESS FOR CONVERTING A WATER-SOLUBLE ALIPHATIC HYDROXYALDEHYDE HAVING 2 TO 10 CARBON ATOMS PER MOLECULE WHICH CONTAINS ONLY CARBON, HYDROGEN, AND HYDROXYL AND ALDEHYDE OXYGEN ATOMS TO THE CORRESPONDING POLYOL BY SUBJECTING SAID ALDEHYDE TO CATALYTIC HYDROGENATION USING A CATALYST OF THE GROUP CONSISTING OF RUTHENIUM AND NICKEL AT ABOUT 50* TO BELOW ABOUT 200* C. AND UNDER A HYDROGEN PRESSURE OF AT LEAST 200 P.S.I.G., THE METHOD OF INCREASING THE EFFECTIVE LIFE OF THE HYDROGENATION CATALYST OF, STARTING THE REACTION BY FEEDING THE ALDEHYDE INTO PREDILUTED AQUEOUS REACTION MEDIUM UNDERHYDROGENATION CONDITIONS SO THE INITIAL CONTACT OF CATALYST WITH ALDEHYDE TAKES PLACE WITH THE CONCENTRATION OF FREE ALDEHYDE IN THE MIXTUREE BELOW 0.05 EQUIVALENTS OF ALDEHYDE PER KILOGRAM OF REACTION MIXTURE, AND CONTINUING THE FEED OF SAID ALDEHYDE TO THE REACTION MIXTURE UNDER HYDROGENATION CONDITIONS AT A RATE OF 0.05 TO 500 POUNDS OF HYDROXYALDEHYDE PER HOUR PER POUND OF HYDROGENATION CATALYST AT WHICH SAID ALDEHYDE CONCENTRATION IS CONTINUED TO BE MAINTAINED BELOW 0.05 EQUIVALENT OF ALDEHYDE PER KILOGRAM OF REACTION MIXTURE THROUGHOUT THE MIXTURE AT ALL TIMES DURING THE REACTION.