Selective hydrogenation of phenylacetylene in the presence of styrene

Claim 2

A process comprising hydrogenating phenylacetylene in the presence of an excess of styrene by contacting a mixture of hydrogen and the phenylacetylene at a hydrogenation temperature of less than about 35° C. with a catalyst obtained by the reduction of a copper compound on a support.

Claim 3

The process of claim 1 wherein the support is a γ-alumina which contains 50 percent by weight or less of γ-alumina and less than 0.15 weight percent each of silicon as SiO 2 and sodium as Na 2 O, and less than 0.01 weight percent sulfur and less than 0.06 weight percent iron as Fe 2 O 3 , and has a surface area of between about 68 and 350 m.sup. 2/g and wherein between about 98 percent and about 40 percent of the pores have a pore diameter between about 40 Å and 120 Å and not more than 25 percent nor less than 2 percent have a pore diameter between 1000 Å to 10,000 Å.

Claim 4

The process of claim 2 wherein the catalyst comprises a mixture of finely divided copper metal and minor amounts of at least one polyvalent activator metal selected from the group consisting of silver, manganese, cobalt, nickel and chromium.

Claim 5

The process of claim 1 wherein the hydrogenation is carried out at a pressure of less than about 10 psig.

Claim 6

The process of claim 4 wherein the hydrogenation is carried out at a pressure of about zero psig.

Claim 7

The process of claim 4 wherein the hydrogen is present in an amount that dissolves in the reactants and is sufficient to hydrogenate the phenylacetylene.

Claim 8

The process of claim 6 wherein less than 30 ppm polymer is formed.

Claim 9

The process of claim 7 wherein less than 10 ppm polymer is formed.

Claim 10

The process of claim 8 wherein less than 2 ppm polymer is formed.

Claim 11

The process of claim 7 wherein the phenylacetylene is reduced to less than 2 ppm.