Catalyst composition useful in the catalytic reduction of sulfur compound contained in a gas stream and a method of making and using such composition

1. A catalyst composition useful in the catalytic reduction of sulfur compounds contained in a gas stream comprising normally gaseous components, wherein said catalyst composition comprises: alumina, a group VI metal component and a group VIII metal component, wherein said catalyst composition has a bimodal pore structure such that greater than 10 percent of the total pore volume of said catalyst composition is contained within pores having a pore diameter greater than 10,000 Å, and such that greater than 10 percent and less than 70 percent of the total pore volume of said catalyst composition is contained within pores having a pore diameter less than 70 {acute over (Å)}.

2. A catalyst composition as recited in claim 1 , wherein the percentage of the total pore volume of said catalyst composition having pores with a pore diameter greater than 10,000 exceeds 15 percent and the percentage of the total pore volume of said catalyst composition having pores with a pore diameter less than 70 {acute over (Å)} exceeds 15 percent.

3. A catalyst composition as recited in claim 2 , wherein said group VI metal component is present in said catalyst composition in an amount in the range upwardly to 20 wt. % and said group VIII metal component is present in said catalyst composition in an amount in the range upwardly to 10 wt. %, wherein the weight percents are based on the metal component being in the oxide form and the total weight of said catalyst composition.

4. A catalyst composition as recited in claim 3 , wherein said catalyst composition has a macroporosity greater than 30%.

5. A catalyst composition as recited in claim 4 , wherein more than 50% of said alumina of said catalyst composition is in the form of η-alumina.

6. A catalyst composition as recited in claim 5 , wherein the percentage of the total pore volume of said catalyst composition that is contained within pores having a pore diameter less than 70 Å is in the range of from 35 to 60 percent.

7. A catalyst composition as recited in claim 6 , wherein said catalyst composition has a total surface area in the range of from 250 m 2 /g to 400 m 2 /g.

8. A catalyst composition for use in the low-temperature catalytic hydrolysis of sulfur compounds that are contained in a normally gaseous stream, wherein said catalyst composition comprises:

alumina;

a group VI metal component; and a group VIII metal component;

wherein said catalyst composition has a pore structure with a bimodal distribution of the size of its pores with a first proportion of the total pore volume of said catalyst composition contained within its pores of pore diameter greater than 10,000 Å exceeding 10 percent of the total pore volume and a second proportion of the total pore volume of said catalyst composition contained within its pores of pore diameter less than 70 Å exceeding 15 percent and less than 70 percent of the total pore volume.

9. A catalyst composition as recited in claim 8 , wherein the ratio of said first proportion to said second proportion (the large/small pore ratio) exceeds 0.6.

10. A catalyst composition as recited in claim 9 , wherein said group VI metal component is present in said catalyst composition in an amount in the range upwardly to 20 wt. % and said group VIII metal component is present in said catalyst composition in an amount in the range upwardly to 10 wt. %, wherein the weight percents are based on the metal component being in the oxide form and the total weight of said catalyst composition.

11. A catalyst composition as recited in claim 10 , wherein said catalyst composition has a macroporosity greater than 30%.

12. A catalyst composition as recited in claim 11 , wherein said catalyst composition has a total pore volume, as measured by mercury porosimetry, in the range of from 0.4 cc/g to 1.2 cc/g.

13. A catalyst composition as recited in claim 12 , wherein more than 50% of said alumina of said catalyst composition is in the form of eta-alumina.

14. A catalyst composition as recited in claim 13 , wherein said catalyst composition has a total surface area in the range of from 250 m 2 /g to 400 m 2 /g.

15. A catalyst composition as recited in claim 12 , wherein more than 75% of said alumina of said catalyst composition is in the form of eta-alumina

16. A catalyst composition as recited in claim 8 , wherein said first proportion exceeds 15 percent of the total pore volume of said catalyst composition and said second proportion exceeds 15 percent of the total pore volume of said catalyst composition.

17. A catalyst composition as recited in claim 16 , wherein said catalyst composition has a macroporosity greater than 35%.

18. A catalyst composition as recited in claim 17 , wherein the ratio of said first proportion to said second proportion (the large/small pore ratio) exceeds 0.75.

19. A catalyst composition as recited in claim 18 , wherein said group VI metal component is present in said catalyst composition in an amount in the range upwardly to 20 wt. % and said group VIII metal component is present in said catalyst composition in an amount in the range upwardly to 10 wt. %, wherein the weight percents are based on the metal component being in the oxide form and the total weight of said catalyst composition.

20. A catalyst composition as recited in claim 8 , wherein said first proportion exceeds 25 percent of the total pore volume of said catalyst composition and said second proportion exceeds 25 percent of the total pore volume of said catalyst composition.

21. A catalyst composition as recited in claim 20 , wherein said catalyst composition has a macroporosity greater than 40%.

22. A catalyst composition as recited in claim 21 , wherein the ratio of said first proportion to said second proportion (the large/small pore ratio) exceeds 0.75.

23. A catalyst composition as recited in claim 22 , wherein said group VI metal component is present in said catalyst composition in an amount in the range upwardly to 20 wt. % and said group VIII metal component is present in said catalyst composition in an amount in the range upwardly to 10 wt. %, wherein the weight percents are based on the metal component being in the oxide form and the total weight of said catalyst composition.

24. A catalyst composition for use in the low-temperature catalytic hydrolysis of sulfur compounds that are contained in a normally gaseous stream, wherein said catalyst composition comprises:

alumina;

a group VI metal component in an amount in the range of from 3 wt. % to 15 wt. %;

and a group VIII metal component in an amount in the range of from 0.5 wt. % to 6 wt. %;

wherein said catalyst composition has a pore structure with a bimodal distribution of the size of its pores with a first proportion of the total pore volume of said catalyst composition contained within its pores of pore diameter greater than 10,000 Å exceeding 15 percent of the total pore volume and a second proportion of the total pore volume of said catalyst composition contained within its pores of pore diameter less than 70 Å exceeding 15 percent and less than 70 percent of the total pore volume, wherein said catalyst composition has a macroporosity greater than 35%, wherein the ratio of said first proportion to said second proportion (the large/small pore ratio) exceeds 0.6.

25. A catalyst composition as recited in claim 24 , wherein said first proportion exceeds 25 percent of the total pore volume of said catalyst composition, said second proportion exceeds 25 percent of the total pore volume of said catalyst composition, and said macroporosity is greater than 40%.