Base for catalyst, catalyst and methods for producing those
View Patent ↗The present invention provides a catalyst base material and a catalyst which have high strength, high porosity or high activity and methods of producing the catalyst base material and catalyst. The present invention relates to a method of producing a catalyst base material, the method comprising dispersing or dissolving a hydrophilic polymer coagulant as a first component, a water-soluble thickener as a second component, a colloidal inorganic binder as a third component and an inorganic fiber as a fourth component in water to form a catalytic slurry or paste, supporting the catalytic slurry or paste on a net-like substrate such that the meshes of the net-like substrate are filled up with the slurry or paste, by drying and/or calcinating the substrate.
1. A method of producing a catalyst base material, the method comprising:
(a) providing a catalytic base material slurry or paste, wherein the catalytic base material slurry or paste comprises:
(i) a hydrophilic polymer coagulant which has a particle size of 20 to 50 μm and is able to absorb water to form swollen gel-like particles;
(ii) a water soluble thickener;
(iii) a colloidal inorganic binder;
(iv) an inorganic fiber;
(b) supporting the catalytic slurry or paste on a metal, net-like substrate such that the meshes of the metal, net-like substrate are filled up with the slurry or paste; and
(c) drying and/or calcinating the substrate;
wherein the slurry or paste comprises from 0.1 to 2% by weight of the hydrophilic polymer coagulant.
2. A method of producing a catalyst base material according to claim 1 , wherein the catalytic base material slurry or paste further comprises:
(v) an inorganic oxide powder.
3. A method of producing a catalyst base material according to claim 2 , wherein carrying the slurry or paste on the net-like substrate such that the meshes of the net-like substrate are filled up with the slurry or paste comprises:
passing a belt-like sheet as the net-like substrate through the slurry or paste; and
then passing the sheet between a pair of rollers or a pair of scrapers placed at a fixed interval to remove superfluous slurry or paste supported on the sheet.
4. A method of producing a catalyst base material according to claim 1 , wherein the catalytic base material slurry or paste further comprises:
(v) an inorganic porous material having a pore volume of from 0.2 to 1.0 cc/g.
5. A method of producing a catalyst base material according to claim 4 , wherein said inorganic porous material is diatomaceous earth and/or amorphous silica.
6. A method of producing a catalyst base material according to claim 4 , wherein providing the catalytic base material slurry or paste comprises:
mixing (v) the inorganic porous material with water to form a slurry-like material; and
mixing the slurry-like material with (i) the hydrophilic polymer coagulant, (ii) the water soluble thickener, (iii) the colloidal inorganic binder, and (iv) the inorganic fiber.
7. A method of producing a catalyst base material according to claim 6 , wherein said inorganic porous material is diatomaceous earth and/or amorphous silica.
8. A method of producing a catalyst base material according to claim 6 , wherein the ratio by volume of a hydrated gel of the hydrophilic polymer coagulant to the slurry-like material obtained by adding water to the inorganic porous material exceeds 0 and is 2 or less.
9. A method of producing a catalyst base material according to claim 8 , wherein said inorganic porous material is diatomaceous earth and/or amorphous silica.
10. A method of producing a catalyst base material according to claim 1 , wherein said supporting the slurry or paste on the net-like substrate such that the meshes of the net-like substrate are filled up with the slurry or paste comprises:
passing a belt-like sheet as the net-like substrate through the slurry or paste; and
passing the sheet between a pair of rollers or a pair of scrapers placed at a fixed interval to remove superfluous slurry or paste supported on the sheet.
11. A method according to claim 1 , wherein said hydrophilic polymer coagulant comprises one or more polymers selected from a polyacrylic acid amide, copolymers of acrylic acid amide and acrylic acid, derivatives of these polymer, graft copolymers of these polymers, mannan, fucoidan, and organic materials having carboxyl groups.
12. A method according to claim 1 , wherein said water-soluble thickener comprises at least one compound selected from polyvinyl alcohol, carboxy cellulose, albumen and glue.
13. A method according to claim 1 , wherein said colloidal inorganic binder comprises at least one compound selected from a silica sol, an alumina sol and a zirconia sol.
14. A method according to claim 1 , wherein said water soluble thickener is polyvinyl alcohol and said colloidal inorganic binder is colloidal silica.
15. A method of producing a catalyst base material according to claim 1 , wherein said hydrophilic polymer coagulant absorbs water to form gel-like particles swollen 300 to 500 times the self-weight of the hydrophilic polymer coagulant.