Nickel catalysts for reforming hydrocarbons
A catalyst for reforming hydrocarbons may include a catalytically active amount of nickel or nickel oxide dispersed on a metal oxide support. The metal oxide support may be of a single-metal oxide of a first metal or a complex-metal oxide of the first metal and a second metal. A co-catalyst of magnesium oxide (MgO) may anchor the nickel or nickel oxide onto the metal oxide support.
1. A catalyst for reforming hydrocarbons comprising:
a catalytically active amount of nickel or nickel oxide dispersed on a metal oxide support, the metal oxide support being a single-metal oxide of a first metal or a complex-metal oxide of the first metal and a second metal; and
a co-catalyst of magnesium oxide (MgO) anchoring the nickel or the nickel oxide onto the metal oxide support,
wherein the catalyst is represented by the following Chemical Formula 1,
Ni a Mg b [A x B (1-x) ] c O d [Chemical Formula 1]
wherein
A is the first metal and selected from Ce, Si, La, and Al,
B is the second metal and selected from Zr and Y,
a, b, c, d, and x are real numbers, with a:b ranging from about 1:0.5 to about 1:2.3, a:c ranging from about 1:10 to about 1:1, and 0<x≦1.
2. The catalyst for reforming hydrocarbons of claim 1 , wherein the first metal (A) is Ce, the second metal (B) is Zr, and x ranges from about 0.5 to about 0.95.
3. The catalyst for reforming hydrocarbons of claim 1 , wherein the Ni is present in an amount of about 5 wt % to about 20 wt % based on a total weight of the catalyst.
4. The catalyst for reforming hydrocarbons of claim 1 , wherein a:b ranges from about 1:0.7 to about 1:2.1, and a:c ranges from about 1:5 to about 1:1.
5. The catalyst for reforming hydrocarbons of claim 1 , wherein the catalyst is structured such that an increase in an average size of particles of the nickel or the nickel oxide after a hydrocarbon reformation reaction is less than about 35%, as measured from a Ni (111) peak in an X-ray diffraction analysis spectrum, when the catalyst is brought into contact with an input gas stream of CH 4 :CO 2 :N 2 =1:1:1 at a GHSV of about 120,000 h −1 at about 800° C. for about 72 hours.
6. The catalyst for reforming hydrocarbons of claim 1 , wherein the catalyst is structured such that a decrease in dispersion degree of the nickel or the nickel oxide after a hydrocarbon reformation reaction is less than about 5%, as calculated from a hydrogen chemisorption test result under a basis that Ni and H are chemisorbed at a ratio of about 1:1, when the catalyst is brought into contact with an input gas stream of CH 4 :CO 2 :N2=1:1:1 at a GHSV of about 120,000 h −1 at about 800° C. for about 24 hours.
7. A method of manufacturing a catalyst for reforming hydrocarbons that includes a catalytically active amount of nickel or nickel oxide dispersed on a metal oxide support, the metal oxide support being a single-metal oxide of a first metal or a complex-metal oxide of the first metal and a second metal, and a co-catalyst of magnesium oxide (MgO) anchoring the nickel or the nickel oxide onto the metal oxide support, the method comprising:
a) dissolving a water-soluble salt of the first metal, a water-soluble salt of the nickel, a water-soluble salt of magnesium, and, optionally, a water-soluble salt of the second metal in water to provide an aqueous solution;
b) heating the aqueous solution to obtain a heated aqueous solution;
c) adding a precipitating agent to the heated aqueous solution and aging to form a precipitate;
d) filtering the precipitate and washing with water at least once to obtain a filtered precipitate;
e) drying the filtered precipitate to obtain a dried precipitate; and
f) calcinating the dried precipitate,
wherein the catalyst is represented by the following Chemical Formula 1:
Ni a Mg b [A x B (1-x) ] c O d [Chemical Formula 1]
wherein
A is the first metal and selected from Ce, Si, La, and Al,
B is the second metal and selected from Zr and Y,
a, b, c, d, and x are real numbers, with a:b ranging from about 1:0.5 to about 1:2.3, a:c ranging from about 1:10 to about 1:1, and 0<x≦1.
8. The method of claim 7 , wherein the dissolving in step a) includes the water-soluble salt of the first metal, the water-soluble salt of the nickel, the water-soluble salt of the magnesium, and, optionally, the water-soluble salt of the second metal being selected from the group consisting of an acetate salt, a nitrate salt, a sulfate salt, an oxalate salt, a halide, a chloride, and a hydrate thereof.
9. The method of claim 7 , wherein the dissolving in step a) includes adding the water-soluble salt of the nickel in such an amount that results in the nickel being present at about 5 wt % to about 20 wt % based on a total weight of the catalyst for reforming hydrocarbons.
10. The method of claim 7 , wherein the dissolving in step a) includes adding the water-soluble salt of the first metal, the water-soluble salt of the nickel, the water-soluble salt of the magnesium, and, optionally, the water soluble salt of the second metal in such an amount that a:b ranges from about 1:0.7 to about 1:2.1 and a:c ranges from about 1:10 to about 1:1.
11. The method of claim 7 , wherein the dissolving in step a) includes adding the water-soluble salts of the first metal and the second metal in such an amount that x ranges from about 0.5 to about 0.95, the water-soluble salt of the first metal being a water-soluble salt of Ce or the hydrate thereof, the water-soluble salt of the second metal being a water-soluble salt of Zr or a hydrate thereof.
12. The method of claim 7 , wherein the heating in step b) includes maintaining the aqueous solution at a temperature of about 100° C. or lower.
13. The method of claim 7 , wherein the adding in step c) includes the precipitating agent being selected from the group consisting of carbonate salts, hydrogen carbonate salts, oxalate salts, sodium hydroxide, potassium hydroxide, ammonium carbonate, ammonium bicarbonate, ammonium hydroxide, ammonia, and a combination thereof.
14. The method of claim 7 , wherein the adding in step c) includes adding the precipitating agent such that the heated aqueous solution has a pH of about 6 or higher.
15. The method of claim 7 , wherein the aging in step c) includes agitating the heated aqueous solution at a temperature of about 65 to about 90° C. for about 1 to about 10 hours.
16. The method of claim 7 , wherein the drying in step e) includes drying at a temperature of about 30° C. or lower and drying at a temperature of about 90° C. or higher.
17. The method of claim 7 , wherein the calcinating in step f) is performed in an oxygen, air, or inert gas atmosphere at a temperature of about 400 to about 1000° C.
18. The method of claim 7 , further comprising:
reducing the catalyst obtained from the calcinating in step f) at a temperature of about 650° C. to about 1100° C. in a reductive gas atmosphere to activate the catalyst.
19. The method of claim 7 , wherein the method produces the catalyst such that an increase in an average size of particles of the nickel or the nickel oxide after a hydrocarbon reformation reaction is less than about 30%, as measured from a Ni (111) peak in an X-ray diffraction analysis spectrum, when the catalyst is brought into contact with an input gas stream of CH 4 :CO 2 :N 2 =1:1:1 at a GHSV of about 120,000 h −1 at about 800° C. for about 72 hours.
20. The method of claim 7 , wherein the method produces the catalyst such that a decrease in dispersion degree of the nickel or the nickel oxide after a hydrocarbon reformation reaction is less than about 5%, as calculated from a hydrogen chemisorption test result under a basis that Ni and H are chemisorbed at a ratio of about 1:1, when the catalyst is brought into contact with an input gas stream of CH 4 :CO 2 :N 2 =1:1:1 at a GHSV of about 120,000 h −1 at about 800° C. for about 24 hours.
21. A method of reforming hydrocarbons, comprising:
contacting an input gas stream with a catalyst for reforming hydrocarbons, the input gas stream including a hydrocarbon and a reforming material, the catalyst including a catalytically active amount of nickel or nickel oxide dispersed on a metal oxide support, the metal oxide support being a single-metal oxide of a first metal or a complex-metal oxide of the first metal and a second metal, and a co-catalyst of magnesium oxide (MgO) anchoring the nickel or the nickel oxide onto the metal oxide support,
wherein the catalyst is represented by the following Chemical Formula 1:
Ni a Mg b [A x B (1-x) ] c O d [Chemical Formula 1]
wherein
A is the first metal and selected from Ce, Si, La, and Al,
B is the second metal and selected from Zr and Y,
a, b, c, d, and x are real numbers, with a:b ranging from about 1:0.5 to about 1:2.3, a:c ranging from about 1:10 to about 1:1, and 0<x≦1.
22. The method of claim 21 , wherein the contacting includes the Ni being present in an amount of about 5 wt % to about 20 wt % based on a total weight of the catalyst.
23. The method of claim 21 , wherein the contacting includes the first metal (A) being Ce, the second metal (B) being Zr, and x ranging from about 0.5 to about 0.95.
24. The method of claim 21 , wherein the contacting includes a:b ranging from about 1:0.7 to about 1:2.1 and a:c ranging from about 1:5 to about 1:1.
25. The method of claim 21 , wherein the contacting includes the reforming material being selected from the group consisting of water, carbon dioxide, oxygen, atmospheric air, and a combination thereof.
26. The method of claim 21 , wherein the contacting is performed at a reaction temperature of about 500 to about 1000° C. under a pressure of about 0.5 to about 50 atm.