| abstract |
A hydrogenation catalyst prepared by combining a Group VIIIA metal compound and an alkylalumoxane and a hydrogenation process wherein said catalyst is used to hydrogenate compounds or materials containing ethylenic and/or aromatic unsaturation. The Group VIIIA metal compound is selected from the group of compounds consisting of carboxylates, chelates, alkoxides, salts of acids containing sulfur, salts of partial half esters of acids containing sulfur and salts of aliphatic and aromatic sulfonic acids. Nickel and cobalt compounds are preferred for use in preparing the hydrogenation catalyst. Hydrogenation catalysts prepared with methylalumoxane initially exhibit less hydrogenation activity than catalysts known heretofore in the prior art and prepared with a metal alkyl of a metal selected from Groups I, II and III. These catalysts, then, permit or enable greater control over the extent of hydrogenation, particularly when partial hydrogenation is a desired end result. Ultimately, however, the catalyst permits substantially complete hydrogenation of both ethylenic and aromatic unsaturation. Hydrogenation catalysts prepared with higher alkyl (C2-C8) alumoxanes on the other hand are generally more active at all hydrogenation times at least those greater than about 30 minutes. |