# US 11,305,261 B2 · Catalyst, carbon dioxide reducing method, and apparatus for reducing carbon dioxide

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,305,261 B2
- Document ID: US11305261B2
- Status: Granted
- Kind: B2
- Application number: 16/970,440
- Filed: 2019-05-29
- Published: 2021-04-22
- Granted: 2022-04-19
- Earliest claimed: 2018-05-29
- Assignees: Sekisui Chemical Co., Ltd.
- Applicants: Sekisui Chemical Co., Ltd.
- Inventors: Rasika Dasanayake Aluthge; Kenichi Shinmei; Noritoshi Yagihashi; Haruka Nishiyama; Taiyou Mori
- Web page: https://patentgrep.com/patent/US11305261B2

## CPC

- B01J 23/8906: {Iron and noble metals}
- B01D 53/8671: {Removing components of defined structure not provided for in B01D53/8603 - B01D53/8668}
- B01J 21/063: {Titanium; Oxides or hydroxides thereof}
- B01J 21/066: {Zirconium or hafnium; Oxides or hydroxides thereof}
- B01J 21/08: Silica
- B01J 21/10: Magnesium; Oxides or hydroxides thereof
- B01J 23/06: of zinc, cadmium or mercury
- B01J 23/745: Iron
- B01J 23/78: with alkali- or alkaline earth metals
- B01J 23/80: with zinc, cadmium or mercury
- B01J 23/83: with rare earths or actinides
- B01J 35/40: characterised by dimensions, e.g. grain size (in a colloidal state B01J35/23; crystallite size B01J35/77)
- B01J 35/613: {10-100 m2/g}
- B01J 37/0009: {Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst}
- B01J 37/0201: {Impregnation}
- B01J 37/0205: {in several steps}
- B01J 37/0221: {of particles}
- B01J 37/0228: {in several steps}
- B01J 37/0236: {Drying, e.g. preparing a suspension, adding a soluble salt and drying}
- B01J 37/0244: {Coatings comprising several layers}
- B01J 37/088: {Decomposition of a metal salt}
- B01J 37/18: with gases containing free hydrogen
- B01D 2255/1021: Platinum
- B01D 2255/1023: Palladium
- B01D 2255/2047: Magnesium
- B01D 2255/2065: Cerium
- B01D 2255/20738: Iron
- B01D 2257/504: Carbon dioxide
- B01D 2258/0283: Flue gases
- C01B 32/40: Carbon monoxide
- Y02P 20/151: Reduction of greenhouse gas [GHG] emissions, e.g. CO2
- B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28)
- C01B: NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; {METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C}
- Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS

## Abstract

A catalyst of the present invention contains a first transition metal oxide (A1) represented by the general formula M1Ox, wherein M1 represents a transition metal element, and x represents a positive real number, and a metal compound (B1) capable of adsorbing carbon dioxide. The first transition metal oxide (A1) is supported on the metal compound (B1), and the first transition metal oxide (A1) can produce a compound represented by the general formula M1Ox-n by reduction, wherein M1 and x are as defined above, and n represents a positive real number equal to or less than x.

## Claims

### Claim 1

A catalyst comprising:
a first transition metal oxide (A1) represented by the general formula M1Ox, wherein M1 represents a transition metal element, and x represents a positive real number; and
a metal compound (B1) capable of adsorbing carbon dioxide, wherein
the first transition metal oxide (A1) is supported on the metal compound (B1), and
the first transition metal oxide (A1) is capable of generating a compound represented by the general formula M1Ox-n by reduction, wherein M1 and x are as defined above, and n represents a positive real number equal to or less than x,
wherein the catalyst is oxidized by reduction of carbon dioxide and reduced by hydrogen.

### Claim 2 (depends on 1)

The catalyst according to claim 1, wherein the transition metal element represented by M1 is at least one selected from the group consisting of iron, titanium, molybdenum, yttrium, chromium, lanthanum, and niobium.

### Claim 3 (depends on 1)

The catalyst according to claim 1, wherein the metal element constituting the metal compound (B1) is at least one metal selected from the group consisting of beryllium, magnesium, calcium, strontium, barium, and zinc.

### Claim 4 (depends on 1)

The catalyst according to claim 1, wherein the metal compound (B1) is a metal oxide.

### Claim 5 (depends on 1)

A catalyst mixture comprising the catalyst according to claim 1 and an inactive buffering material.

### Claim 6 (depends on 5)

The catalyst mixture according to claim 5, wherein the inactive buffering material is an inorganic oxide.

### Claim 7 (depends on 5)

The catalyst mixture according to claim 5, wherein the inactive buffer material is at least one selected from the group consisting of an oxide containing a group 4 element and an oxide containing a group 14 element.

### Claim 8 (depends on 5)

A carbon dioxide reducing method for reducing carbon dioxide using the catalyst mixture according to claim 5, wherein
a catalyst reduction reaction to reduce the catalyst and a carbon dioxide reduction reaction to reduce carbon dioxide by the catalyst are carried out.

### Claim 9 (depends on 5)

An apparatus for reducing carbon dioxide, comprising the catalyst mixture according to claim 5.

### Claim 10

A catalyst comprising:
a first transition metal oxide (A1) represented by the general formula M1Ox, wherein M1 represents a transition metal element, and x represents a positive real number;
a second transition metal oxide (A2) represented by the general formula M2Oy, wherein M2 is a transition metal element different from M1, and y is a positive real number; and
a metal compound (B1) capable of adsorbing carbon dioxide, wherein
the first transition metal oxide (A1) is supported on the metal compound (B1),
the second transition metal oxide (A2) is supported on the metal compound (B1), and
the first transition metal oxide (A1) is capable of generating a compound represented by the general formula M1Ox-n by reduction, wherein M1 and x are as defined above, and n represents a positive real number equal to or less than x.

### Claim 11 (depends on 10)

The catalyst according to claim 10, wherein the transition metal element represented by M2 is cerium.

### Claim 12 (depends on 10)

The catalyst according to claim 10, wherein the transition metal element represented by M1 is iron, and the transition metal element represented by M2 is cerium.

### Claim 13 (depends on 10)

The catalyst according to claim 10, wherein a mass ratio of the second transition metal element represented by M2 to the first transition metal element represented by M1 (second transition metal element/first transition metal element) is 5/95 or more and 80/20 or less.

### Claim 14 (depends on 10)

The catalyst according to claim 10, wherein the transition metal element represented by M1 is at least one selected from the group consisting of iron, titanium, molybdenum, yttrium, chromium, lanthanum, and niobium.

### Claim 15 (depends on 10)

The catalyst according to claim 10, wherein the metal element constituting the metal compound (B1) is at least one metal selected from the group consisting of beryllium, magnesium, calcium, strontium, barium, and zinc.

### Claim 16 (depends on 10)

The catalyst according to claim 10, wherein the metal compound (B1) is a metal oxide.

### Claim 17 (depends on 10)

A catalyst mixture comprising the catalyst according to claim 10 and an inactive buffering material.

### Claim 18 (depends on 17)

The catalyst mixture according to claim 17, wherein the inactive buffering material is an inorganic oxide.

### Claim 19 (depends on 17)

The catalyst mixture according to claim 17, wherein the inactive buffer material is at least one selected from the group consisting of an oxide containing a group 4 element and an oxide containing a group 14 element.

### Claim 20 (depends on 17)

A carbon dioxide reducing method for reducing carbon dioxide using the catalyst mixture according to claim 17, wherein
a catalyst reduction reaction to reduce the catalyst and a carbon dioxide reduction reaction to reduce carbon dioxide by the catalyst are carried out.

### Claim 21 (depends on 17)

An apparatus for reducing carbon dioxide, comprising the catalyst mixture according to claim 17.

### Claim 22

A catalyst comprising:
a first transition metal oxide (A1) represented by the general formula M1Ox, wherein M1 represents a transition metal element, and x represents a positive real number;
a metal compound (B1) capable of adsorbing carbon dioxide; and
a platinum-based compound (C1), wherein
the first transition metal oxide (A1) is supported on the metal compound (B1), and
the first transition metal oxide (A1) is capable of generating a compound represented by the general formula M1Ox-n by reduction, wherein M1 and x are as defined above, and n represents a positive real number equal to or less than x.

### Claim 23 (depends on 22)

The catalyst according to claim 22, wherein the transition metal element represented by M1 is at least one selected from the group consisting of iron, titanium, molybdenum, yttrium, chromium, lanthanum, and niobium.

### Claim 24 (depends on 22)

The catalyst according to claim 22, wherein the metal element constituting the metal compound (B1) is at least one metal selected from the group consisting of beryllium, magnesium, calcium, strontium, barium, and zinc.

### Claim 25 (depends on 22)

The catalyst according to claim 22, wherein the metal compound (B1) is a metal oxide.

### Claim 26 (depends on 22)

A catalyst mixture comprising the catalyst according to claim 22 and an inactive buffering material.

### Claim 27 (depends on 26)

The catalyst mixture according to claim 26, wherein the inactive buffering material is an inorganic oxide.

### Claim 28 (depends on 26)

The catalyst mixture according to claim 26, wherein the inactive buffer material is at least one selected from the group consisting of an oxide containing a group 4 element and an oxide containing a group 14 element.

### Claim 29 (depends on 26)

A carbon dioxide reducing method for reducing carbon dioxide using the catalyst mixture according to claim 26, wherein
a catalyst reduction reaction to reduce the catalyst and a carbon dioxide reduction reaction to reduce carbon dioxide by the catalyst are carried out.

### Claim 30 (depends on 26)

An apparatus for reducing carbon dioxide, comprising the catalyst mixture according to claim 26.

### Claim 31

A carbon dioxide reducing method for reducing carbon dioxide using a catalyst,
wherein a catalyst reduction reaction to reduce the catalyst and a carbon dioxide reduction reaction to reduce carbon dioxide by the catalyst are carried out, and
wherein the catalyst comprises:
a first transition metal oxide (A1) represented by the general formula M1Ox, wherein M1 represents a transition metal element, and x represents a positive real number; and
a metal compound (B1) capable of adsorbing carbon dioxide, wherein
the first transition metal oxide (A1) is supported on the metal compound (B1), and
the first transition metal oxide (A1) is capable of generating a compound represented by the general formula M1Ox-n by reduction, wherein M1 and x are as defined above, and n represents a positive real number equal to or less than x.

### Claim 32 (depends on 31)

The carbon dioxide reducing method according to claim 31, wherein a reaction temperature in the carbon dioxide reduction reaction is equal to or higher than an equilibrium reaction onset temperature of the metal compound (B1).

### Claim 33 (depends on 32)

The carbon dioxide reducing method according to claim 32, wherein the reaction temperature in the carbon dioxide reduction reaction is 700° C. or less.

### Claim 34 (depends on 31)

The carbon dioxide reducing method according to claim 31, wherein the transition metal element represented by M1 is at least one selected from the group consisting of iron, titanium, molybdenum, yttrium, chromium, lanthanum, and niobium.

### Claim 35 (depends on 31)

The carbon dioxide reducing method according to claim 31, wherein the metal element constituting the metal compound (B1) is at least one metal selected from the group consisting of beryllium, magnesium, calcium, strontium, barium, and zinc.

### Claim 36 (depends on 31)

The carbon dioxide reducing method according to claim 31, wherein the metal compound (B1) is a metal oxide.

### Claim 37 (depends on 31)

The carbon dioxide reducing method according to claim 31, wherein the catalyst is a catalyst mixture comprising the catalyst and an inactive buffering material.

### Claim 38 (depends on 37)

The carbon dioxide reducing method according to claim 37, wherein the inactive buffering material is an inorganic oxide.

### Claim 39 (depends on 37)

The carbon dioxide reducing method according to claim 37, wherein the inactive buffer material is at least one selected from the group consisting of an oxide containing a group 4 element and an oxide containing a group 14 element.

### Claim 40

An apparatus for reducing carbon dioxide, comprising a first reactor containing a catalyst, a carbon dioxide supplier, a hydrogen supplier, and a switching system,
wherein the first reactor is coupled by the switching system alternately to the carbon dioxide supplier or to the hydrogen supplier, and
wherein the catalyst comprises:
a first transition metal oxide (A1) represented by the general formula M1Ox, wherein M1 represents a transition metal element, and x represents a positive real number; and
a metal compound (B1) capable of adsorbing carbon dioxide, wherein
the first transition metal oxide (A1) is supported on the metal compound (B1), and
the first transition metal oxide (A1) is capable of generating a compound represented by the general formula M1Ox-n by reduction, wherein M1 and x are as defined above, and n represents a positive real number equal to or less than x.

### Claim 41 (depends on 40)

The apparatus for reducing carbon dioxide according to claim 40, further comprising a second reactor comprising the catalyst, wherein the first reactor and the second reactor are coupled by the switching system alternately to the carbon dioxide supplier or to the hydrogen supplier.

### Claim 42 (depends on 40)

The apparatus for reducing carbon dioxide according to claim 40, wherein the transition metal element represented by M1 is at least one selected from the group consisting of iron, titanium, molybdenum, yttrium, chromium, lanthanum, and niobium.

### Claim 43 (depends on 40)

The apparatus for reducing carbon dioxide according to claim 40, wherein the metal element constituting the metal compound (B1) is at least one metal selected from the group consisting of beryllium, magnesium, calcium, strontium, barium, and zinc.

### Claim 44 (depends on 40)

The apparatus for reducing carbon dioxide according to claim 40, wherein the metal compound (B1) is a metal oxide.

### Claim 45 (depends on 40)

The apparatus for reducing carbon dioxide according to claim 40, wherein the catalyst is a catalyst mixture comprising the catalyst and an inactive buffering material.

### Claim 46 (depends on 40)

The apparatus for reducing carbon dioxide according to claim 40, wherein the inactive buffering material is an inorganic oxide.

### Claim 47 (depends on 40)

The apparatus for reducing carbon dioxide according to claim 40, wherein the inactive buffer material is at least one selected from the group consisting of an oxide containing a group 4 element and an oxide containing a group 14 element.