CATALYTIC COMPOSITION FOR CO2 CONVERSION

Abstract

The present invention relates to a catalytic composition comprising at least 7 different elements selected from the group consisting of the elements defined by the intersection of the second to the sixth period and the first to the sixteenth group of the periodic table of the elements, whereby technetium is excluded, and a matrix component. A method for use of the catalytic composition is also provided.

Claims

1. Catalytic composition comprising at least 7 different elements selected from the group consisting of the elements defined by the intersection of the second to the sixth period and the first to the sixteenth group of the periodic table of the elements, whereby technetium is excluded, forming the catalyst and a matrix component, wherein the catalyst is dispersed.

2. Catalytic composition according to claim 1, whereby the matrix is a porous matrix.

3. Catalytic composition according to any of claim 1 or 2, whereby the matrix has a surface to weight ratio of at least 40 m.sup.2/g.

4. Catalytic composition according to any one of the preceding claims, whereby the at least one matrix component is selected from the group consisting of natural aluminosilicates, synthetic aluminosilicates, zeolites, vermiculite, activated carbon, obsidian, titanium oxide, aluminum oxide, and mixtures thereof.

5. Catalytic composition according to any one of claims 1 to 4, whereby the at least 7 elements are selected from the group consisting of Al, C, Cd, Ce, Co, Cr, Cu, Eu, Fe, Gd, Mo, Mo, Na, Nd, Ni, O, and Sm.

6. Method for preparing synthesis gas and hydrocarbon compounds from a CO.sub.2-containing gas comprising the steps of mixing the CO.sub.2-containing gas with water vapor and subsequently contacting the mixture with a catalytic composition according to any one of claims 1 to 5.

7. Method according to claim 6, whereby the method is carried out at a temperature below 250 C., preferably a temperature in the range of 100 C. to 180 C., preferably in the range of 120 C. to 160 C. and most preferably in the range of 130 C. to 150 C.

8. Method according to any of claim 6 or 7, whereby the method is carried out at low pressure, preferably at below 10 bars, more preferably in the range of 0.1 to 2 bar.

9. Method according to any one of claims 6 to 8, whereby the CO.sub.2-containing gas is exhaust gas of a combustion.

10. Method according to any one of claims 6 to 8, whereby the CO.sub.2-containing gas is exhaust gas of a power plant, smelting plant or cement plant.

11. Method according to any one of claims 6 to 8, whereby the CO.sub.2-containing gas is unpurified exhaust gas.

12. Method according to any one of claims 6 to 8, whereby the heat energy of the CO.sub.2-containing gas is employed to carry out the catalytic reaction.

13. Method according to any one of claims 6 to 8 for conversion of CO.sub.2 to flammable gases wherein the conversion rate is more than 30%, more preferably more than 50% or even more preferably more than 95%.

14. Apparatus for conducting the method according to any one of the claims 6 to 13 comprising an inlet pipe CO.sub.2-containing gas, a water inlet pipe, a heating mean for generating water vapor and heating a catalytic composition, a reaction vessel comprising the catalytic composition, and an outlet pipe for discharging the reaction products, whereby the reaction vessel is flow-connected with the inlet pipes and the outlet pipe.

15. Apparatus according to claim 14, whereby the reaction vessel is a single chamber reactor or plug flow reactor.

Description

[0033] The method for the conversion of CO.sub.2 and the apparatus for conducting the method according to the present invention are explained in more detail below with reference to exemplary embodiments in the drawings, in which, purely schematically:

[0034] FIG. 1 shows a flow chart of the method according to the present invention;

[0035] FIG. 2 shows an apparatus for conducting the method according to the present invention;

[0036] FIG. 1 shows a flow chart depicting the steps of the method. In a first step water is heated to generate water vapor. The water vapor is then mixed with the CO.sub.2-containing gas which mixture is subsequently contacted with the heated catalytic composition.

[0037] FIG. 2 shows an apparatus for conducting the method according to the present invention. The apparatus 15 comprises a heater 10, said heater 10 is used for heating the catalytic composition 5 that is arranged at regular intervals in different zones in a plug flow reactor. The heater 10 is also used to heat water which is fed from a water barrel 8 to a spiral shaped pipe 9. By heating the water in the spiral shaped pipe 9 water vapor is generated. The exhaust pipe 12 collects the exhaust gases of the heater 10 that serve as a CO.sub.2-containing gas, said CO.sub.2-containing gas is pumped by mean of a gas pump 1 through pipes 2 and 3 where the gas stream passes a pressure controller 6 connected to the pipe 3 via a valve 4. Before the CO.sub.2-containing gas enters the plug-flow reactor it passes an inlet where the generated water vapor is mixed with the CO.sub.2-containing gas. In the plug flow reactor, the mixture of CO.sub.2-containing gas and water vapor is contacted with the heated catalytic mixture. Finally, the reaction mixture comprising the product compounds passes to an outlet pipe 11 where it may be collected for further purification or use.

[0038] In the following examples of the catalytic composition according to the present invention are described in more detail. The following examples show different catalyst compositions. All catalyst compositions were tested for their activity in converting CO.sub.2 in exhaust gases to synthesis gas and/or hydrocarbons. The catalytic composition comprises the matrix components and the catalyst components. Amounts of the different compounds are given weight-% of the catalytic composition.

TABLE-US-00001 Example Example Example Example Example 1 2 3 4 5 Al.sub.2O.sub.3 12.0 15.0 8.0 4.0 0.0 C 10.0 Cd 2.0 1.0 Ce 5.0 3.0 2.0 Co 10.0 10.0 Cr.sub.2O.sub.3 8.0 8.0 4.0 3.0 Cu 7.0 10.0 6.0 3.0 3.0 Eu 0.5 FeO 6.0 Fe.sub.2O.sub.3 20.0 Fe.sub.3O.sub.4 12.0 Gd 1.5 MoO.sub.3 16.0 3.0 Mo.sub.3O.sub.7 10.0 3.0 NaOH 8.0 Nd 2.0 Ni 5.0 10.0 NiO 5.0 10.0 18.0 5.0 Sm 1.0 2.0 1.0 Obsidian 25.0 30.0 47.0 30.0 Vermiculite 25.0 20.0 50.0

[0039] The catalytic compositions of examples number 1 to 5 were subsequently placed in a plug flow reactor and tested for their catalytic activity in converting CO.sub.2-containing gas streams into synthesis gas and/or other hydrocarbon compounds. The reactor was heated to 140 C. CO.sub.2-containing gas and water vapor were mixed in the reactor and subsequently contacted with the catalytic composition. Samples of the gas stream were collected at the outlet pipe and subsequently analyzed.

TABLE-US-00002 Gas stream at outlet (components given in weight-%) Example H.sub.2 CO CO.sub.2 H.sub.2O CH.sub.4 C.sub.2H.sub.4 1 70 10 14 3 2 1 2 11 11 65 10 2 1 3 16 8 42 29 4 1 4 46 16 10 15 12 1 5 63 7 15 10 4 1

[0040] Yet in other experiments also further reaction products are found in various concentration. These additional products are for example, but not limited to Methanol, Ethanol, Acetylene, Benzene and Formaldehyde.