Catalysts and process for producing same

Abstract

A catalyst, a hydrocarbon steam reforming catalyst, and a method for producing the same are provided. A catalytic metal containing at least Ni is supported on a composite oxide containing R, Zr, and oxygen, at a composition of not less than 10 mol % and not more than 90 mol % of R, not less than 10 mol % and not more than 90 mol % of Zr, and not less than 0 mol % and not more than 20 mol % of M (M: elements other than oxygen, R, and Zr), with respect to the total of the elements other than oxygen being 100 mol %, wherein the composite oxide has a specific surface area of 11 to 90 m 2 /g, and the largest peak in the wavelength range of 200 to 800 cm −1 of Raman spectrum with a full width at half maximum of 20 to 72 cm −1 .

1 . A catalyst comprising a catalytic metal comprising at least Ni, supported on a composite oxide, wherein said composite oxide comprises R(R stands for Ce or a mixture of Ce and Pr), Zr, and oxygen, at a composition of not less than 10 mol % and not more than 90 mol % of R, not less than 10 mol % and not more than 90 mol % of Zr, and not less than 0 mol % and not more than 20 mol % of M (M stands for elements other than oxygen, R, and Zr), with respect to a total of said elements other than oxygen being 100 mol %, wherein said composite oxide has a specific surface area of 11 to 90 m 2 /g, and a largest peak in the wavelength range of 200 to 800 cm −1  of Raman spectrum with a full width at half maximum of 20 to 72 cm −1 . 
     
     
         2 . The catalyst according to  claim 1 , wherein said composite oxide has a composition of not less than 50 mol % and not more than 80 mol % of R, not less than 20 mol % and not more than 50 mol % of Zr, and not less than 0 mol % and not more than 20 mol % of M, with respect to a total of said elements other than oxygen being 100 mol %. 
     
     
         3 . The catalyst according to  claim 1 , wherein said composite oxide has a specific surface area of 20 to 40 m 2 /g, and a largest peak in the wavelength range of 200 to 800 cm −1  of Raman spectrum with a full width at half maximum of 30 to 60 cm −1 . 
     
     
         4 . The catalyst according to  claim 3 , wherein said composite oxide has a specific surface area of 20 to 40 m 2 /g, and a largest peak in the wavelength range of 200 to 800 cm −1  of Raman spectrum with a full width at half maximum of 30 to 45 cm −1 . 
     
     
         5 . The catalyst according to  claim 1 , wherein an amount of said catalytic metal is 0.1 to 10 mol % with respect to a total of R, Zr, and M in the composite oxide being 100 mol %. 
     
     
         6 . The catalyst according to  claim 1 , wherein said catalytic metal further comprises, in addition to Ni, at least one element selected from Cu, Fe, Pt, Pd, and Rh. 
     
     
         7 . A hydrocarbon steam reforming catalyst comprising the catalyst of  claim 1 . 
     
     
         8 . A method for producing the catalyst of  claim 1 , comprising:
 (a) preparing a mixed solution of a cerium solution not less than 80 mol % of which cerium ions are tetravalent, and zirconium hydroxide,   (b) neutralizing said mixed solution to obtain a precursor of a composite oxide,   (c) adding a surfactant to said precursor and mixing,   (d) calcining said precursor mixed with the surfactant to obtain a composite oxide, and   (e) making said composite oxide support a catalytic metal comprising at least Ni.   
     
     
         9 . The method according to  claim 8 , wherein said mixed solution in said step (a) contains an aqueous solution of element M. 
     
     
         10 . The method according to  claim 8 , further comprising, after said step (c) and before said step (d), a step of impregnating said precursor mixed with the surfactant with an aqueous solution of element M, or mixing said precursor mixed with the surfactant with a salt or oxide of element M. 
     
     
         11 . The method according to  claim 8 , wherein said calcining in said step (d) is carried out at 800 to 1100° C. 
     
     
         12 . The method according to  claim 8 , further comprising before said step (b), a step of holding under heating said mixed solution obtained in step (a).