Cadmium-containing catalyst

Claim 2

A catalyst composition comprising a cadmium component and a support material comprising at least one of a crystalline borosilicate molecular sieve and a pillared smectite or vermiculite clay, wherein the cadmium component is in the form of the elemental metal, its oxide or salt or a combination thereof, and wherein the cadmium component is present at a concentration level in the range of from about 0.1 to about 20 weight percent, calculated as cadmium oxide and based on the weight of the catalyst.

Claim 3

The catalyst composition of claim 1 wherein the cadmium component is in the form of cadmium oxide.

Claim 4

The catalyst composition of claim 1 wherein the cadmium component is present at a concentration level in the range of from about 1 to about 10 weight percent, calculated as cadmium oxide and based on the weight of the catalyst.

Claim 5

The catalyst composition of claim 1 wherein the crystalline borosilicate molecular sieve comprises a molecular sieve material having the following composition in terms of mole ratios of oxides: 0.9±0.2M.sub.2/n O:B.sub.2 O.sub.3 :ySiO.sub.2 :zH.sub.2 O wherein M is at least one cation having a valence of n, y is between 4 and about 600, and z is between 0 and about 160, and providing an X-ray diffraction pattern comprising the following X-ray diffraction lines and assigned strengths: ______________________________________ ˜d (Å) Assigned Strength ______________________________________ 11.2 ± 0.2 W-VS 10.0 ± 0.2 W-MS 5.97 ± 0.07 W-M 3.82 ± 0.05 VS 3.70 ± 0.05 MS 3.62 ± 0.05 M-MS 2.97 ± 0.02 W-M 1.99 ± 0.02 VW-M ______________________________________

Claim 6

The catalyst composition of claim 1 wherein the pillared smectite or vermiculite clay comprises a multiplicity of cations interposed between the molecular layers of the clay and maintaining the spacing between the molecular layers in the range of from about 6 angstroms to about 10 angstroms at a temperature of at least 300° C. in an air atmosphere for at least 2 hours.

Claim 7

The catalyst composition of claim 1 wherein the support comprises from about 20 to about 95 weight percent of an amorphous refractory inorganic oxide and from about 5 to about 80 weight percent of the crystalline borosilicate molecular sieve or pillared smectite or vermiculite clay.

Claim 8

The catalyst composition of claim 6 wherein the refractory inorganic oxide comprises alumina, zirconia, titania, an oxide of a metal of the lanthanide series, an oxide of a metal of the actinide series, a combination thereof, or a combination thereof with silica or magnesia.