Water gas shift process

Claim 2

In a process for the preparation of hydrogen which comprises contacting a gas mixture comprising carbon monoxide and steam with minor amounts of hydrocarbon under shift reaction conditions with a catalyst comprising: (i) an alkali metal compound derived from an acid having an ionization constant less than about 1 × 10 -3 , (ii) a hydrogenation-dehydrogenation component selected from the group consisting of (a) a non-noble metal composition comprising the oxides or sulfides of vanadium, molybdenum, tungsten, cobalt, tantalum or niobium or mixtures thereof or (b) mixtures of non-noble metal compounds comprising the oxides or sulfides of vanadium, molybdenum, tungsten, cobalt, tantalum or niobium or mixtures thereof with oxides or sulfides of nickel, iron or chromium or mixtures thereof, the weight ration of said hydrogenation-dehydrogenation component to said alkali metal compound, each calculated on the basis of the oxides thereof, being less than about 5:1, the oxides or sulfides of nickel, iron or chromium or mixtures thereof making up less than about 80 mole % of the total hydrogenation-dehydrogenation component, the improvement which comprises incorporating at least 0.01 weight % of a halogen component into said catalyst, thereby improving the activity maintenance characteristics of said catalyst.

Claim 3

The process of claim 1 wherein said alkali metal compound is an alkali metal carbonate.

Claim 4

The process of claim 1 wherein said halogen component is chlorine.

Claim 5

The process of claim 1 wherein said hydrogenation-dehydrogenation component is a mixture of the oxides or sulfides of cobalt and molybdenum.

Claim 6

The process of claim 4 wherein said alkali metal compound is an alkali metal carbonate.

Claim 7

The process of claim 1 wherein said catalyst is contained on a support.

Claim 8

The process of claim 6 wherein said support is alumina.

Claim 9

The process of claim 1 wherein said gas mixture contains less than about 200 vppm of a sulfur bearing compound.

Claim 10

In a process for the preparation of hydrogen which comprises contacting a gas mixture comprising carbon monoxide and steam and less than about 200 vppm of a sulfur material in a reaction zone at a temperature varying from about 200° F. to 925° F. and at an elevated pressure with a catalyst to form a reaction mixture, the temperature within said reaction zone being maintained above the dew point temperature of the reaction mixture and the pressure within said reaction zone being maintained below the dew point pressure of the reaction mixture, said catalyst comprising (i) an alkali metal compound derived from an acid having an ionization constant less than about 1 × 10 -3 , (ii) a hydrogenation-dehydrogenation component comprising (a) the oxides or sulfides of vanadium, molybdenum, tungsten, or cobalt or mixtures thereof, and (b) mixtures of the oxides or sulfides of vanadium, molybdenum, tungsten, or cobalt or mixtures thereof with the oxides or sulfides of nickel, iron or chromium or mixtures thereof, said catalyst being contained on a support with at least a portion of said alkali metal compound or hydrogenation-dehydrogenation component being in a sulfide form, the weight ratio of said hydrogenation-dehydrogenation component to said alkali metal compound, each calculated on the basis of the oxide thereof, being in the range of about 0.001:1 to about 5:1, the oxides or sulfides of nickel, iron or chromium making up less than about 80 mole % of the total hydrogenation-dehydrogenation component, the improvement which comprises incorporating at least 0.01 weight % of a chlorine component into said catalyst, thereby improving the activity maintenance characteristics of said catalyst.

Claim 11

In a process for the preparation of hydrogen which comprises contacting a gas mixture comprising carbon monoxide and steam and less than about 200 vppm of a sulfur material in a reaction zone at a temperature varying from about 200° F. to 925° F. and at an elevated pressure with a catalyst to form a reaction mixture, the temperature within said reaction zone being maintained above the dew point temperature of the reaction mixture and the pressure within said reaction zone being maintained below the dew point pressure of the reaction mixture, said catalyst comprising (i) an alkali metal compound derived from an acid having an ionization constant less than about 1 × 10 -3 , (ii) a hydrogenation-dehydrogenation component comprising (a) the oxides or sulfides of vanadium, molybdenum, tungsten, or cobalt or mixtures thereof, and (b) mixtures of the oxides or sulfides of vanadium, molybdenum, tungsten, or cobalt or mixtures thereof with the oxides or sulfides of nickel, iron or chromium or mixtures thereof, said catalyst being contained on a support with at least a portion of said alkali metal compound or hydrogenation-dehydrogenation component being in a sulfide form, the weight ratio of said hydrogenation-dehydrogenation component to said alkali metal compound, each calculated on the basis of the oxide thereof, being in the range of about 0.001:1 to about 5:1, the oxides or sulfides of nickel, iron or chromium making up less than about 80 mole % of the total hydrogenation-dehydrogenation component, the improvement which comprises incorporating at least 0.01 weight % of a chlorine component into said catalyst, thereby improving the activity maintenance characteristics of said catalyst.

Claim 12

The process of claim 9 wherein said alkali metal compound is an alkali metal carbonate.

Claim 13

The process of claim 9 wherein said process is conducted at a pressure varying from about 200 to 3000 psig and at a space velocity of at least 300 volumes of gas mixture per volume of supported catalyst per hour.

Claim 14

The process of claim 9 wherein said support is alumina.

Claim 15

The process of claim 9 wherein the temperature in the reaction zone ranges from about 250° F. to about 700° F.

Claim 16

The process of claim 9 wherein said alkali metal compound is potassium carbonate.

Claim 17

The process of claim 14 wherein said hydrogenation-dehydrogenation component is a mixture of the oxides or sulfides of cobalt and molybdenum.

Claim 18

The process of claim 15 wherein said support is alumina.

Claim 19

The process of claim 1 wherein the weight ratio of said hydrogenation-dehydrogenation component to said alkali metal compound, each calculated on the basis of the oxide thereof, is less than about 3:1.