utilizes nickel to catalyze the reaction between Carbon Dioxide and Hydrogen, which reaction produces both Water and Methane.
The "Ru", Ruthenium, catalyst specified herein likely wasn't available to Paul Sabatier, back in the day, although it was discovered and named in the 1800's.
A Platinum Group metal, it is, unfortunately, rather exquisitely rare, although it can be obtained as the byproduct of mining and separating other, more abundant precious metals. More can be learned about it via:
The upside is that it does serve just as a catalyst in the process, and wouldn't be consumed, or "used up", to any appreciable extent. Obtaining it would be more like a capital investment; and, only a thin coating, that is, a small amount, of it on a substrate would be needed.
Furthermore, we have cited both a couple of the named inventors and the Assignee, previously, in our reports concerning the treatment of Carbon Dioxide as a raw material resource, rather than as a noxious pollutant.
Special note must be made, though, of the lead named inventor, Michael Gratzel, or, variously, "Graetzel".
As seen in:
Michael Grätzel - Wikipedia, the free encyclopedia; "Michael Grätzel ... is a professor at the Ecole Polytechnique Federale de Lausanne where he directs the Laboratory of Photonics and Interfaces. He pioneered research on energy and electron transfer reactions in mesoscopic-materials and their optoelectronic applications. He discovered a new type of solar cell ... and pioneered the use of nanomaterials in lithium ion batteries. Author of over 900 publications, two books and inventor or co-inventor of over 50 patents, he has been the Mary Upton Visiting Professor at Cornell University and a Distinguished Visiting Professor at the National University of Singapore. He was an Invited Professor at the University of Berkeley. His work has been cited over 88’000 times ... making him one of the 10 most highly cited chemists in the world. He was a frequent guest scientist at the National Renewable Energy Laboratory in Golden, CO";
Gratzel is an extraordinarily accomplished, and well-traveled, chemist. So, it is little wonder that his services were engaged by the named Assignee, the Gas Research Institute, of Chicago, to further the development of the technology for recycling Carbon Dioxide, since, as demonstrated, for just two examples, in our reports:
West Virginia Coal Association | Chicago Recycles CO2 to Methane | Research & Development; concerning: "United States Patent 4,609,440 - Electrochemical Synthesis of Methane; 1986; Assignee: Gas Research Institute, Chicago; Abstract: A method is described for electrochemically reducing carbon dioxide to form methane by electrolyzing an aqueous solution containing carbon dioxide utilizing a cathode which comprises ruthenium. If desired, solar energy can be utilized to provide the potential for the electrolyzing. A method for electrochemically reducing carbon dioxide to form methane"; and:
Chicago Recycles CO2 to Methanol | Research & Development; concerning: "United States Patent 4,609,441 - Electrochemical Reduction of Aqueous Carbon Dioxide to Methanol; 1986; Assignee: Gas Research Institute, Chicago; Abstract: A method of producing methanol from carbon dioxide is set forth. A solution of carbon dioxide in an aqueous solvent having electrolyte dissolved therein is electrolyzed utilizing a molybdenum cathode. Faradaic efficiency is generally quite high and without detectable corrosion. A method of producing methanol from carbon dioxide (which comprises) electrolyzing a solution of carbon dioxide in an aqueous solvent having an electrolyte therein and utilizing a cathode which comprises molybdenum to produce methanol";
that organization had a demonstrated interest in the development of CO2 utilization technology.)
Claims: A mixed ruthenium catalyst comprising a mixture of about 10 to about 90 mole percent Ru and about 10 to about 90 mole percent RuOx, wherein x is a number greater than 0 and equal to or less than 2, highly dispersed on a support selected from the group consisting of semiconducting oxides selected from the group consisting of TiO2, ZrO2 ... and Al2O3, and zeolites.
(We remind you that "zeolites" are well-known minerals; and, as seen, for just one example, in:
West Virginia Coal Association | Mobil Oil 1978 Coal Conversion with Zeolite Catalyst | Research & Development; concerning: "United States Patent 4,086,262 - Conversion of Synthesis Gas to Hydrocarbon Mixtures; 1978; Assignee: Mobil Oil Corporation; Abstract: Contacting a mixture of carbon monoxide and hydrogen with an intimate mixture of a carbon monoxide reduction catalyst, such as a Fischer-Tropsch catalyst or a methanol synthesis catalyst, and an acidic crystalline aluminosilicate having a pore dimension greater than about 5 Angstroms to produce hydrocarbon mixtures useful in the manufacture of heating fuels, high octane gasoline, aromatic hydrocarbons, and chemicals intermediates. A method for producing hydrocarbons, which comprises: contacting synthesis gas ... with a heterogeneous catalyst (comprising) an inorganic carbon monoxide reducing catalyst and a selective acidic crystalline aluminosilicate ... wherein said acidic crystalline aluminosilicate is a H-ZSM-5 crystalline zeolite. This invention is concerned with an improved process for converting synthesis gas, i.e., mixtures of gaseous carbon oxides with hydrogen or hydrogen donors, to hydrocarbon mixtures. Processes for the conversion of coal ... to a gaseous mixture consisting essentially of hydrogen and carbon monoxide, or of hydrogen and carbon dioxide, or of hydrogen and carbon monoxide and carbon dioxide, are well known"; are frequently specified for use as catalysts, or catalyst substrates, in a variety of Carbon conversion, and hydrocarbon synthesis, technologies.)
A catalyst ... wherein said semiconducting oxide is TiO2.
(As in our above, introductory citation of "Visible Light Photoreduction of CO2; 2009; National Energy Technology Laboratory, USDOE, Pittsburgh, PA"; "Titanium Dioxide", "TiO2", is frequently specified as a catalytic component in light-driven Carbon conversion and synthesis processes of this sort.)
A catalyst ... wherein said mixture is about 15 to about 35 mole percent Ru and about 65 to about 85 mole percent RuOx.
A catalyst ... wherein loading of said mixture on said support is about 1 to about 15 weight percent of the total mixed ruthenium/support material catalyst.
A catalyst ... wherein said support is Al2O3 (or) a zeolite.
Background and Field: Heterogeneous catalytic gas phase methane production from hydrogen and carbon dioxide is achieved directly at temperatures as low as 25 C and at atmospheric pressures by use of a catalyst having a mixture of Ru and RuOx, wherein x is greater than 0 and equal to or less than 2, supported by a suitable metal oxide support.
Photo-methanation using such catalysts having photo excitable support materials significantly increases methane production.
Summary: It is an object of this invention to provide a low pressure and low temperature process for the direct formation of methane from carbon dioxide and hydrogen ... providing a very selective yield of methane of greater than about 95 percent, and preferably greater than 99 percent."
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First, we note that elemental, molecular Hydrogen is required for this efficient Carbon Dioxide recycling technology. As seen, for one example, in our report of:
some efficient solar-driven technologies for evolving Hydrogen from Water do exist; and, in fact, as we will document in future reports, both Michael Gratzel and the Gas Research Institute of Chicago have that base, variously and separately, covered as well.
And, in conclusion, we must again remind you, that, as seen in just one out of now many examples:
Exxon 2010 CO2 + Methane = Liquid Hydrocarbons | Research & Development; concerning: "United States Patent 7,772,447 - Production of Liquid Hydrocarbons from Methane; 2010; Assignee: ExxonMobil; Abstract: (A) process for converting methane to liquid hydrocarbons ... the process comprising: (a) contacting a feed containing methane and ... H2O (and) CO2 with a (specified) catalyst under conditions effective to convert said methane to aromatic hydrocarbons"; we can react the Methane, made so efficiently via the process of our subject herein, "United States Patent 4,847,231 - Mixed Ruthenium Catalyst", from Carbon Dioxide, with even more Carbon Dioxide, as recovered from whatever convenient and economical source, with both the CO2-derived Methane and the additional Carbon Dioxide being converted through such reaction into "liquid hydrocarbons".
