Chromium-free water gas shift catalyst
Catalyst for use in the high temperature shift reaction comprising in its active form a mixture of zinc alumina spinel and zinc oxide in combination with an alkali metal selected from the group consisting of Na, K, Rb, Cs and mixtures thereof.
1. A process for enriching a synthesis gas mixture in hydrogen by contacting said synthesis gas mixture with a catalyst consisting in its active form of a mixture of zinc alumina spinel and zinc oxide in combination with an alkali metal selected from the group consisting of Na, K, Rb, Cs and mixtures thereof, said catalyst having a Zn/Al molar ratio in the range 0.5 to 1.0 and a content of alkali metal in the range 0.4 to 8.0 wt % based on the weight of oxidized catalyst.
2. A process for enriching a synthesis gas mixture in carbon monoxide by contacting said synthesis gas mixture with a catalyst consisting in its active form of a mixture of zinc alumina spinel and zinc oxide in combination with an alkali metal selected from the group consisting of Na, K, Rb, Cs and mixtures thereof, said catalyst having a Zn/Al molar ratio in the range 0.5 to 1.0 and a content of alkali metal in the range 0.4 to 8.0 wt % based on the weight of oxidized catalyst.
3. Process according to claim 1 , wherein said synthesis gas mixture has S/G ratio of 0.05 to 0.9, a temperature of 300 to 400° C. and the reactor operates at a gas pressure in the range 2.3 to 6.5 MPa.