Integral catalyst for selectively oxidizing CO in hydrogen-rich reformed gas

Abstract

The invention discloses a catalyst for selectively oxidizing CO in hydrogen-rich reformed gas, in particular relates to an integral catalyst for selectively oxidizing the CO in the hydrogen-rich reformed gas, and belongs to the field of CO preferential oxidization catalysts. The active component of the catalyst is Ru, the content of which is 0.1 to 2 weight percent calculated by Ru; a catalytic auxiliary agent is one or more of alkali metal oxides or / and alkaline earth oxides; the molar ratio of the Ru to the alkali metal oxides or / and metal elements of the alkali metal oxides is 1-20:1; and the rest component is a dichroite carrier coated with alumina gel, wherein the content of the alumina gel accounts for 2 to 10 weight percent of the content of the catalyst. The integral catalyst has the characteristics of high activity, high CO selection, low content of noble metal, low ignition temperature, wide temperature range, and capacity of being conveniently applied to a fuel cell system,and can deeply eliminate the CO in the reformed gas and provide clean fuel for fuel cells.

Description

technical field [0001] The invention relates to a catalyst for selectively oxidizing CO in hydrogen-rich reformed gas, in particular to a monolithic catalyst for selectively oxidizing CO in hydrogen-rich reformed gas. Background technique [0002] Proton Exchange Membrane Fuel Cell (PEMFC) is a power generation device that directly converts chemical energy into electrical energy through electrochemical reactions. Compared with traditional power generation devices, it has high energy conversion efficiency, no pollution, low noise, and adaptability With the advantages of different power requirements, it has broad application prospects as a fixed power supply (such as a power station) and a mobile power supply for electric vehicles, submarines, aerospace, etc. One form of energy. As the fuel of the PEMFC system, hydrogen mainly comes from the reforming reaction of methanol or natural gas, so 2-15% CO will inevitably remain in the hydrogen. Since a small amount of CO can poiso...

AI Technical Summary

Problems solved by technology

[0007] 1. The content of precious metals is too high, causing the cost to rise

[0008]2. Catalyst ignition temperature is too high, catalyst selectivity is low

[0009]3. The active temperature zone is too narrow

[0010]4. Due to the preparation and pretreatment method of the catalyst, the performance of the catalyst is not high

[0011] U.S. Patent US20020147107 invented a catalyst that can be applied to selectively oxidize CO in hydrogen-rich reformed gas. The catalyst is to load Ru on alumina pellets by impregnation method, which can reduce the CO concentration in reformed gas. to less than 50ppm, but the loading of Ru in the catalyst is higher, reaching 0.5-3%

[0012] Chinese patent CN1216796C invented a catalyst that can be applied to selectively oxidize CO in hydrogen-rich reformed gas. The active component of the catalyst is Pt, Ru or The alloy of the two, Pt or Ru is loaded on the support by the method of incipient wetness impregnation, and the obtained reformed gas with reduced CO concentration can be used as fuel for fuel cells, but the loading of noble metals in the catalyst is also high, around 3%

However, the activity of the catalyst is low, and the highest effective working temperature range can only reach 85%, the concentration of CO outlet is too high, and the purified reformed gas still cannot meet the standard as fuel gas for fuel cells

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