TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Process: In the process (M1) the copper hydroxide precipitate is formed by drop-wise addition of an aqueous solution of ammonia to an aqueous solution of copper nitrate, at a pH of 6 - 9. The copper hydroxide precipitate is dried in air. The copper hydroxide particles are heated in an oxidizing atmosphere at 200 - 350degreesC (preferably 250degreesC) for at least 2 hours. Activating copper oxide particles involves heating the copper oxide particles comprising oxygen (15 - 25%), carbon monoxide (2 - 5%) and argon (balance) at 100degreesC.Preferred Components: The copper salt comprises copper nitrate.Preferred Compound: The copper oxide catalyst particles comprise a metastable form or nanoscale particles of copper oxide. EXAMPLE - Copper hydroxide was precipitated from a mixture comprising an aqueous solution of copper nitrate dihydrate (0.5 M) and an aqueous solution of ammonia (15%). The ammonia solution was added dropwise to the copper nitrate solution in an amount sufficient to bring the pH of the mixture to 7.5. The precipitated copper hydroxide was vacuum filtered, washed, and dried in air at near ambient temperature for 48 hours. Copper oxide particles were formed by heating (calcining) the dried precipitate at 10degreesC/min to 250degreesC in air for 2 hrs and then cooling the copper oxide particles to room temperature. The particles were heated to 100degreesC in a gas mixture comprising carbon monoxide (3.6%) and oxygen (21%) argon (balance) (1000 ml/min.) and then cooling to room temperature in flowing argon (250 ml/min.) to give the copper oxide particles (test). The activity of selected copper oxide catalysts was evaluated using a continuous flow packed bed reactor and compared with a commercially available copper oxide particles (control). A test sample (100 mg) comprising particles of copper oxide catalyst was placed between two beds of glass wool inside the quartz tube. An input reactant gas mixture was introduced at an upstream side of the quartz tube and is passed through the quartz tube and over the catalyst particles at atmospheric pressure at a total gas flow rate of 1000 ml/min. An input reactant gas mixture was used to optionally activate the copper oxide catalyst particles and to measure the oxidation of carbon monoxide in the presence of an external source of oxygen. The input reactant gas mixture was comprised of carbon monoxide (3.6% ) and oxygen (21%) argon (balance). After attaining a steady state flow of gas, the temperature of the furnace was increased at a heating rate of 10degreesC/min. Alternatively, the catalytic efficiency of the copper oxide catalyst was evaluated at near ambient temperature by not increasing the temperature of the furnace. During room temperature measurements, where exothermic oxidation of carbon monoxide to carbon dioxide was increase the temperature of the copper oxide catalyst, air was flowed over the external surface of the quartz tube to maintain the temperature of the catalyst below 30degreesC. The gas that passed over the catalyst particles and emerges from the downstream side of a quartz tube and analyzed by an analyzer with a data acquisition system that measured the concentration of carbon monoxide, carbon dioxide and oxygen in the gas. The temperature at which 5% of the carbon monoxide was converted to carbon dioxide (T5), the temperature at which about 50% of the carbon monoxide is converted to carbon dioxide (T50) and the temperature corresponding to full conversion (T100) was determined. The result showed that no oxidation behavior was observed for the commercially available copper oxide below about 150degreesC while complete conversion of carbon monoxide to carbon dioxide was observed for the calcined copper oxide particles at about 150degreesC.