United States Patent: 7332147
We have reported on multiple technologies for the productive and profitable use of Carbon Dioxide, some of them entailing it's use to synthesize higher hydrocarbon, including liquid fuels, and even as a supplement to some primary processes of indirect Coal-to-Liquid conversion.
The enclosed technology, recently patented in the United States, as documented herein, seems to be a version of that latter use for Carbon Dioxide; or, rather, a refinement of that use; whereby, as we have earlier documented from other sources to be feasible and practical, steam can be employed both as an agent of hydrogenation, and, as a co-reactant that helps to prevent carbon deposition on, and thereby extends the life of, the catalyst used for reforming Carbon Dioxide with simple hydrocarbons, such as Methane, to synthesize higher hydrocarbons of greater value and utility.
Comment follows excerpts from:
"United States Patent 7,332,147 - Process for reforming hydrocarbons with Carbon Dioxide
February 19, 2008
Inventors: Akira Takahashi, et. al. (Japan)
Assignee: NGK Insulators, Ltd. (Nagoya, Japan)
Abstract: A process is provided for reforming a hydrocarbon with carbon dioxide using a selectively permeable membrane reactor including a catalyst for accelerating a chemical reaction and a selectively permeable membrane exhibiting selective permeability, wherein a carbon dioxide reforming reaction of the hydrocarbon is accelerated by the catalyst to produce reaction products, and a specific component among the reaction products is allowed to pass through the selectively permeable membrane so specific component is selectively separated. The process includes the steps of adding steam to a raw material gas containing the hydrocarbon and the carbon dioxide and supplying the raw material gas mixture to the selectively permeable membrane reactor.
Claims: A process for reforming a hydrocarbon with carbon dioxide using a selectively permeable membrane reactor including a catalyst for accelerating a chemical reaction and a selectively permeable membrane exhibiting selective permeability, wherein a carbon dioxide reforming reaction of the hydrocarbon is accelerated by the catalyst to produce reaction products including hydrogen, and the hydrogen is allowed to pass through the selectively permeable membrane so that the hydrogen is selectively separated from the reaction products, the process comprising the steps of: adding steam to a raw material gas containing the hydrocarbon and the carbon dioxide to form a raw material gas mixture; and supplying the raw material gas mixture to the selectively permeable membrane reactor; wherein the hydrocarbon is methane, a molar composition ratio of the carbon dioxide to the methane (CO2/CH4) in the raw material gas mixture is 1.0 to 3.0, and a molar composition ratio of the steam to the carbon dioxide (H2O/CO2) is 0.01 to 0.3.
Summary: The present invention provides a process for reforming a hydrocarbon with carbon dioxide using a selectively permeable membrane reactor including a catalyst for accelerating a chemical reaction and a selectively permeable membrane exhibiting selective permeability, wherein a carbon dioxide reforming reaction of the hydrocarbon is accelerated by the catalyst and a specific component among reaction products produced by the reaction is selectively separated by allowing the specific component to pass through the selectively permeable membrane, the process comprising adding steam to a raw material gas containing the hydrocarbon and the carbon dioxide and supplying the mixture to the selectively permeable membrane reactor.
According to the present invention, inactivation of the catalyst due to coking can be reduced when carrying out the carbon dioxide reforming reaction of the hydrocarbon using the permeable membrane reactor, whereby the reaction can be efficiently and stably carried out over a long time. The present invention may be applied for a carbon dioxide reforming reaction of various hydrocarbons such as methane, ethane, propane, butane, kerosine, methanol, and diethyl ether, and is expected to provide a technology for effectively utilizing a biomass gas and a low-quality natural gas field."
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And, yet again, the Methane, as herein specified to be a reactant for Carbon Dioxide, can itself be synthesized, via the Sabatier process, from Carbon Dioxide; or, from the steam-gasification of Coal.
Ostensibly, the end product of this invention seems to be simple Hydrogen. However, one of the other potentials for it is revealed in the description of Background Art, as found in the full Patent:
"A reaction between a hydrocarbon such as methane or propane and steam or carbon dioxide is called a reforming reaction, which has been industrially carried out as means for obtaining a synthesis gas (hydrogen and carbon monoxide) or hydrogen used as fuel for fuel cells."
Both "synthesis gas" and "hydrogen", can be produced efficiently, from Carbon Dioxide and Steam, using this technology. Hydrogen is one thing. But, once we have the synthesis gas, it can be processed and condensed, as in Fischer-Tropsch and other technologies, into liquid hydrocarbons suitable for refining into conventional liquid fuels.
Strange, isn't it?
We don't, in the United States, publicly acknowledge that Carbon Dioxide is a valuable raw material resource which can be used to synthesize hydrocarbon fuels. However, we do, as herein, officially recognize and accept the fact that other people, in other nations, do acknowledge that Carbon Dioxide is a valuable raw material resource which can be used to synthesize hydrocarbon fuels.