Catalyst for oxidizing carbon monoxide and method of manufacturing the same

Abstract

A catalyst that oxidizes carbon monoxide includes a bimetal consisting of platinum and a transition metal in a bimetallic phase that is loaded on γ-alumina support. The catalyst is manufactured by uniformly mixing a platinum precursor, a transition metal precursor, and γ-alumina (γ-Al2O3) in a dispersion medium to provide a mixture; drying the mixture; calcining the dried mixture; and reducing the calcined dried mixture. Since the catalyst that oxidizes carbon monoxide has high reaction activity even at low temperature and excellent reaction selectivity, and a methanation reaction and reoxidization do not occur, and the catalyst can effectively eliminate carbon monoxide in the fuel.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application claims the benefit of Korean Application No. 2005-99620, filed Oct. 21, 2005, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference. BACKGROUND OF THE INVENTION [0002] 1. Field of the Invention [0003] Aspects of the present invention relate to a catalyst for oxidizing carbon monoxide and a method of manufacturing the same. More particularly, aspects of the present invention relate to a catalyst for oxidizing carbon monoxide having high reaction activity and excellent reaction selectivity in which a methanation reaction and reoxidation do not occur, and a method of manufacturing the same. [0004] 2. Description of the Related Art [0005] Fuel cells are electricity generation systems that directly convert the chemical energy of oxygen and the hydrogen in hydrocarbons such as methanol, ethanol, and natural gas to electrical energy. [0006] Fuel cell systems consist of a fuel c...

AI Technical Summary

Benefits of technology

[0019] Aspects of the present invention provide a PROX catalyst having excellent reaction selectivity and a broad operating temperature range in which a methanation reaction and reoxidation do not occur.

[0021] Aspects of the present invention also provide a fuel processor including the PROX catalyst having excellent reaction selectivity and a broad operating temperature range in which a methanation reaction and reoxidation do not occur.

[0022] Aspects of the present invention also provide a fuel cell system including the PROX catalyst having excellent reaction selectivity and a broad operating temperature range in which a methanation reaction and reoxidation do not occur.

[0027] The catalyst that oxidizes carbon monoxide according to aspects of the present invention has excellent selectivity for carbon monoxide and a fast reaction rate in a carbon monoxide oxidizing reaction. In addition, efficiency of the entire reaction increases since a methanation reaction and reoxidization do not occur. Thus, the carbon monoxide in the fuel can effectively be eliminated using the catalyst according to aspects of the present invention.

Problems solved by technology

A high-temperature shift reaction is performed at a temperature of 400 to 500° C. Generally, a high-temperature shift reaction is followed by a low-temperature shift reaction at a temperature of 200 to 300° C. Even after these reactions are performed, it is very difficult to reduce the CO levels to less than 5,000 ppm.

Another serious potential problem is that a methanation reaction may occur between CO to be removed and reformed hydrogen, as represented by Reaction Scheme 4 below.

It is important to inhibit this reaction since even limited methanation reactions can lead to a significant decrease in the hydrogen concentration and can affect the efficiency of the entire reforming process.

Conventional catalysts for oxidizing carbon monoxide in the PROX reaction have low reaction selectivity.

Further, when conventional catalysts are used, the methanation reaction partially occurs and the conventional catalysts lose reactivity by becoming reoxidized by oxygen in the reaction device during the catalytic operations or during intervals between operations.

Therefore, it is necessary to develop a PROX catalyst that has a high reaction activity and excellent reaction selectivity, and that does not support a methanation reaction or become reoxidized.

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