Catalytic hydrogenation of unsaturated dinitriles employing high purity alumina

A process for the catalytic hydrogenation of an unsaturated dinitrile feedstock comprising at least one unsaturated dinitrile compound of the formula ##STR8## wherein each R is individually selected from the group consisting of an alkylene radical and an alkylidene radical, R' is an alkyl radical, and the number of carbon atoms in said compound is in the range of 7 to 30;

• which comprises contacting said feedstock under suitable hydrogenation conditions with a secondary amine formation suppressant, hydrogen, a suitable diluent, and a supported catalyst to thereby effect the at least substantially complete hydrogenation of said at least one unsaturated dinitrile compound to the corresponding branched-chain saturated aliphatic diamine;
• said supported catalyst comprising a catalytic component and a catalyst support, said catalyst support consisting essentially of alumina having a purity of at least 99.5 weight percent after calcination, said catalytic component being selected from the group consisting of elemental ruthenium, elemental rhodium, elemental palladium, elemental cobalt, elemental nickel and compounds of ruthenium, rhodium, palladium, cobalt or nickel which are reducible by hydrogen to the respective elemental metal at said hydrogenation conditions.