Catalytic supports with controlled pore properties

A catalyst support comprising (A)(I) a Group IIB metal compound selected from the group consisting of zinc and cadmium compounds, (II) a combination of said zinc and cadmium compounds or (III) a combination of at least one of said Group IIB metals compounds with at least one Group IIA metal compound selected from the group consisting of magnesium, calcium, strontium and barium compounds;

• (B) alumina and (C) aluminum phosphate matrix, characterized after calcination at 500.degree. C. for about 10 hours as amorphous, and having an average pore radius of from about 10 A to about 300 A, a surface area ranging from about 80 m.sup.2 /g to about 350 m.sup.2 /g, a pore volume of from about 0.3 cc/g to about 1.5 cc/g and wherein component (A) is present in an amount ranging from about 0.5 to about 75 mole percent, component (B) is present in an amount ranging from about two to about 90 mole percent and component (C) is present in an amount ranging from about three to about 95 mole percent.