# US 7,744,846 B2 · Method for forming activated copper oxide catalysts > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,744,846 B2 - Document ID: US7744846B2 - Status: Granted - Kind: B2 - Application number: 11/370,843 - Filed: 2006-03-09 - Published: 2007-01-18 - Granted: 2010-06-29 - Earliest claimed: 2005-03-11 - Assignees: Philip Morris USA Inc. - Inventors: Sarojini Deevi; Unnikrishnan Pillai - Web page: https://patentgrep.com/patent/US7744846B2 ## CPC - B01D 53/864: {Removing carbon monoxide or hydrocarbons} - A24B 15/282: {by indirect addition of the chemical substances, e.g. in the wrapper, in the case} - A24B 15/287: {by inorganic substances only} - A24B 15/288: {Catalysts or catalytic material, e.g. included in the wrapping material} - A24D 3/16: of inorganic materials - B01D 53/944: {Simultaneously removing carbon monoxide, hydrocarbons or carbon making use of oxidation catalysts (three-way-catalysts [TWC] B01D53/9445)} - B01J 23/72: Copper - B01J 35/45: Nanoparticles - B01J 37/031: {Precipitation} - B01J 37/14: with gases containing free oxygen - B01D 2255/20761: Copper - B01D 2257/502: Carbon monoxide - Y02A 50/20: Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters - Y02P 70/50: Manufacturing or production processes characterised by the final manufactured product - 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) - A24B: MANUFACTURE OR PREPARATION OF TOBACCO FOR SMOKING OR CHEWING; TOBACCO; SNUFF - A24D: CIGARS; CIGARETTES; TOBACCO SMOKE FILTERS; MOUTHPIECES OF CIGARS OR CIGARETTES; MANUFACTURE OF TOBACCO SMOKE FILTERS OR MOUTHPIECES - B01J: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS - Y02A: TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract A method for forming a copper oxide catalyst includes forming a precipitate of copper hydroxide from a copper salt solution; forming dried particles of copper hydroxide by drying the precipitate at a temperature of less than 30° C.; heating the copper hydroxide particles to form copper oxide; and activating the copper oxide. The copper oxide catalyst includes particles of copper oxide. Copper oxide catalyst particles can preferably include a metastable form of copper oxide. The copper oxide catalyst particles are useful for low-temperature and near-ambient temperature catalysis and/or oxidation of carbon monoxide to carbon dioxide. ## Claims ### Claim 1 A method of forming particles of a copper oxide carbon monoxide catalyst comprising: forming a precipitate of copper hydroxide from a copper salt solution; optionally filtering the precipitate; drying the copper hydroxide precipitate at a temperature of less than about 30° C. to form copper hydroxide particles; heating the copper hydroxide particles to form copper oxide particles; and activating the copper oxide particles in an atmosphere comprising oxygen and carbon monoxide, wherein the copper salt comprises copper nitrate, and wherein the copper hydroxide particles are heated in an oxidizing atmosphere at a temperature of between about 200° C. and 350° C. ### Claim 2 (depends on 1) The method of claim 1 wherein the copper hydroxide precipitate is formed by drop-wise addition of an aqueous solution of ammonia to an aqueous solution of copper nitrate. ### Claim 3 (depends on 1) The method of claim 1, wherein the copper hydroxide precipitate is formed at a pH of between about 6 and 9. ### Claim 4 (depends on 1) The method of claim 1, wherein the copper hydroxide precipitate is dried in air. ### Claim 5 (depends on 1) The method of claim 1, wherein the activating comprises heating the copper oxide particles in an atmosphere comprising oxygen and carbon monoxide at a temperature of about 100° C. ### Claim 6 (depends on 1) The method of claim 1, wherein the activating comprises heating the copper oxide particles in an atmosphere comprising 15 to 25% oxygen, 2 to 5% carbon monoxide and balance argon at a temperature of about 100° C. ### Claim 7 A method of forming particles of a copper oxide carbon monoxide catalyst comprising: forming a precipitate of copper hydroxide from a copper salt solution; optionally filtering the precipitate; drying the copper hydroxide precipitate at a temperature of less than about 30° C. to form copper hydroxide particles; heating the copper hydroxide particles to form copper oxide particles; and activating the copper oxide particles in an atmosphere comprising oxygen and carbon monoxide, wherein the copper salt comprises copper nitrate, and wherein the copper hydroxide particles are heated in air at a temperature of between about 200° C. and 350° C. for at least about 2 hours. ### Claim 8 (depends on 7) The method of claim 7, wherein the copper hydroxide precipitate is formed by drop-wise addition of an aqueous solution of ammonia to an aqueous solution of copper nitrate. ### Claim 9 (depends on 7) The method of claim 7, wherein the copper hydroxide precipitate is formed at a pH of between about 6 and 9. ### Claim 10 (depends on 7) The method of claim 7, wherein the copper hydroxide precipitate is dried in air. ### Claim 11 (depends on 7) The method of claim 7, wherein the activating comprises heating the copper oxide particles in an atmosphere comprising oxygen and carbon monoxide at a temperature of about 100° C. ### Claim 12 (depends on 7) The method of claim 7, wherein the activating comprises heating the copper oxide particles in an atmosphere comprising 15 to 25% oxygen, 2 to 5% carbon monoxide and balance argon at a temperature of about 100° C. ### Claim 13 A method of forming particles of a copper oxide carbon monoxide catalyst comprising: forming a precipitate of copper hydroxide from a copper salt solution; optionally filtering the precipitate; drying the copper hydroxide precipitate at a temperature of less than about 30° C. to form copper hydroxide particles; heating the copper hydroxide particles to form copper oxide particles; and activating the copper oxide particles in an atmosphere comprising oxygen and carbon monoxide, wherein the copper salt comprises copper nitrate, and wherein the copper hydroxide particles are heated in air at a temperature of about 250° C. for 2 hours. ### Claim 14 (depends on 13) The method of claim 13, wherein the copper hydroxide precipitate is formed by drop-wise addition of an aqueous solution of ammonia to an aqueous solution of copper nitrate. ### Claim 15 (depends on 13) The method of claim 13, wherein the copper hydroxide precipitate is formed at a pH of between about 6 and 9. ### Claim 16 (depends on 13) The method of claim 13, wherein the copper hydroxide precipitate is dried in air. ### Claim 17 (depends on 13) The method of claim 13, wherein the activating comprises heating the copper oxide particles in an atmosphere comprising oxygen and carbon monoxide at a temperature of about 100° C. ### Claim 18 (depends on 13) The method of claim 13, wherein the activating comprises heating the copper oxide particles in an atmosphere comprising 15 to 25% oxygen, 2 to 5% carbon monoxide and balance argon at a temperature of about 100° C.