CO conversion catalyst for use in fuel cell in DSS operation, method for producing the same, and fuel cell system
AssigneeMitsubishi Heavy Industries, Ltd.
InventorsMasanao Yonemura, Toshinobu Yasutake, Tetsuya Shishido
Life of this patent
Estimating the term…
Abstract
To provide a CO conversion catalyst for use in a fuel cell in a DSS operation, which includes a Cu—Al-Ox catalyst, in which the Cu—Al-Ox catalyst has a boehmite phase formed in at least a part of the Cu—Al-Ox catalyst. The CO conversion catalyst has an improved degree of dispersion of Cu metal by the boehmite phase formed therein, and hence can be prevented from sintering of copper caused due to steam, thereby achieving improved durability with respect to the function as the CO conversion catalyst.
Claims11
A carbon monoxide conversion catalyst for use in a daily startup and shutdown operation of a fuel cell, comprising an amorphous Cu—Al-Ox catalyst which includes a boehmite phase formed in at least a part of the Cu—Al-Ox catalyst which is obtainable by
- individually dropping solutions of respective nitrates of Cu and Al to ion-exchanged water, stirring to dissolve, and adding a precipitant to the resultant solution to precipitate Cu and Al;
- maturing the solution in which Cu and Al are precipitated to form a precursor;
- collecting the obtained catalyst by filtration, after drying, calcining at about 550° C. to give an amorphous Cu—Al-Ox conversion catalyst in which amorphous AlyOx and Cu0 particles are dispersed;
- and
- exposing the calcined CO conversion catalyst to a temperature of 50 to 250° C. in a satured stream atmosphere at 70° C. or higher to form a boehmite phase in a part of the amorphous catalyst.
A method for producing a carbon monoxide conversion catalyst for use in a daily startup and shutdown operation of a fuel cell, the method comprising:
- individually dropping solutions of respective nitrates of Cu and Al to ion-exchanged water, stirring to dissolve, and adding a precipitant to the resultant solution to precipitate Cu and Al;
- maturing the solution in which Cu and Al are precipitated to form a precursor;
- collecting the obtained catalyst by filtration, after drying, calcining at about 550° C. to give an amorphous Cu—Al-Ox conversion catalyst in which amorphous AlyOx and Cu0 particles are dispersed;
- and
- exposing the calcined CO conversion catalyst to a temperature of 50 to 250° C. in a satured stream atmosphere at 70° C. or higher to form a boehmite phases in a part of the amorphous catalyst
- wherein the Cu0 particles are from 1.20 to 1.93 times as large as the boehmite phases.
Dependencies are inferred from the claim text.