Method of CO and/or CO₂hydrogenation to higher hydrocarbons using doped mixed-metal oxides

摘要

A method of hydrogenation utilizing a reactant gas mixture comprising a carbon oxide and a hydrogen agent, and a hydrogenation catalyst comprising a mixed-metal oxide containing metal sites supported and/or incorporated into the lattice. The mixed-metal oxide comprises a pyrochlore, a brownmillerite, or mixtures thereof doped at the A-site or the B-site. The metal site may comprise a deposited metal, where the deposited metal is a transition metal, an alkali metal, an alkaline earth metal, or mixtures thereof. Contact between the carbon oxide, hydrogen agent, and hydrogenation catalyst under appropriate conditions of temperature, pressure and gas flow rate generate a hydrogenation reaction and produce a hydrogenated product made up of carbon from the carbon oxide and some portion of the hydrogen agent. The carbon oxide may be CO, CO2, or mixtures thereof and the hydrogen agent may be H2. In a particular embodiment, the hydrogenated product comprises olefins, paraffins, or mixtures thereof.

主权项

1. A method of conducting a reaction process comprising:
delivering a reactant gas mixture comprising a carbon oxide and a hydrogen agent; providing a catalyst comprising a deposited metal supported on a mixed-metal oxide, wherein the deposited metal comprises a transition metal, an alkali metal, an alkaline earth metal, a noble metal, or mixtures thereof, and wherein the mixed-metal oxide comprises a doped pyrochlore, a doped brownmillerite, or mixtures thereof wherein: the doped pyrochlore has a pyrochlore composition A2-xA′xB2-yB′yO7-z wherein,
A is one or more of a lanthanide series metal, Ca, or mixtures thereof,A′ is one or more of a Group 1 metal, a Group 2 metal, or mixtures thereof,B is one or more of a transition metal, Si, Ge, Sn, Pb, Ce, or mixtures thereof,B′ is one or more of a noble metal and,0≦x≦1, 00, and z is a number that renders the composition charge neutral, the doped brownmillerite has a brownmillerite composition A2-xA′xB2-yB′yO5-z wherein,
A is one or more of an alkaline earth metal,A′ is one or more of a lanthanide series metal, a Group 3 metal, or mixtures thereof,B is one or more of a transition metal, a Group 13 metal, or mixtures thereof,B′ is one or more of a lanthanide series metal, a noble metal, a Group 3 metal, or mixtures thereof and,0≦x≦1, 00, and z is a number that renders the composition charge neutral; and contacting the reactant gas mixture and the catalyst and maintaining the reactant gas mixture and the catalyst at conditions of temperature, pressure and gas flow rate to generate a reaction and produce a reaction product, the reaction product comprising carbon from the carbon oxide and at least some portion of the hydrogen agent, and the reaction product having at least a 15% product selectivity for the paraffins, olefins, or mixtures thereof and having less than a 20% product selectivity for oxygenated hydrocarbons, wherein a ratio S/Y is at least 10, where S is a number of catalytically active surface sites deposited onto the mixed-metal oxide, and Y is a number of catalytically active sites present as B′ in the mixed-metal oxide.