By way of foreword, this is "just" another dispatch confirming that Carbon Dioxide, as recovered from whatever convenient source, can be, in combination with Water, H2O, efficiently converted into various hydrocarbons, and/or other products of value, through a process based on electrolysis.
And, it is another such technology emerging from that technological and industrial giant, United Technologies, about whose CO2 recycling expertise we earlier reported, in the very-closely related:
West Virginia Coal Association | United Technologies Converts CO2 to Formic Acid | Research & Development; concerning: "United States Patent 4,921,585 - Electrolysis Cell and Method of Use; 1990; Assignee: United Technologies Corporation; Abstract: The present invention discloses an improved solid polymer electrolysis cell for the reduction of carbon dioxide. The improvement being the use of a cathode having a metal phthalocyanine catalyst which results in the suppression of the formation of hydrogen during the reduction process and the subsequent improved conversion efficiency for carbon dioxide.(and) an improved electrolysis cell useful in the production of oxygen and the reduction of carbon dioxide. The improvement comprises the selection of the cathode material (which) will improve the conversion efficiency of carbon dioxide in the presence of hydrogen ions to organic compounds. The most prevalent reaction is the reduction of carbon dioxide to formic acid".
In that dispatch, and in some others documenting, from other sources, the fact that Carbon Dioxide can be efficiently converted into "formic acid", we explained the rather surprising utility of that product substance, including the fact that it can be utilized in some technologies for the hydrogenation and liquefaction of Coal.
But, we do understand that "formic acid" just doesn't have the pizzazz for our general readership as do things like Methane and Methanol, so, herein, we document how, in a process contiguous with that of "United States Patent 4,921,585 - Electrolysis Cell and Method of Use", United Technologies explains how the same type of technology can be used to convert Carbon Dioxide into those sorts of things, as well.
As seen in excerpts from the initial link in this dispatch to the immediately-subsequent and identically-titled:
"United States Patent 4,921,586 - Electrolysis Cell and Method of Use
Date: May, 1990
Inventor: Trent Molter, CT
Assignee: United Technologies Corporation, Hartford
(In case you're curious, see:
United Technologies Corporation - Wikipedia, the free encyclopedia; "United Technologies Corporation is an American multinational conglomerate ... . It researches, develops, and manufactures high-technology products in numerous areas, including aircraft engines, helicopters, HVAC, fuel cells, elevators and escalators, fire and security, building systems, and industrial products, among others. UTC is also a large military contractor, producing missile systems and military helicopters".)
Abstract: The present invention discloses an improved solid polymer electrolysis cell for the reduction of carbon dioxide. The improvement being the use of a cathode having a metal phthalocyanine catalyst which results in the suppression of the formation of hydrogen during the reduction process and the subsequent improved conversion efficiency for carbon dioxide.
Claims: An improved electrolysis cell for the reduction of carbon dioxide having an anode, a cathode and a solid polymer electrolyte, the improvement comprising a primary carbon dioxide reducing cathode containing a catalytic material having a hydrogen overvoltage greater than platinum and a secondary carbon dioxide reducing cathode having a hydrogen overvoltage greater than platinum thereby resulting in the suppression of the formation of hydrogen gas and improved efficiency for the reduction of carbon dioxide.
The cell ... wherein the secondary catalyst is in the form of one or more screens (and) wherein the screens comprise stainless steel, copper, brass, niobium, zirconium, or titanium.
The cell ... wherein the secondary catalyst comprises a screen comprising a carbon dioxide reducing material having a hydrogen overvoltage greater than platinum wherein said screen is substantially coated with a carbon dioxide reducing catalyst having a hydrogen overvoltage greater than platinum.
(If you're really interested in the technicalities, see:
JSTOR: Proceedings of the National Academy of Sciences of the United States of America, Vol. 5, No. 5 (May 15, 1919), pp. 160-; "Hydrogen Overvoltage; Duncan Macinnes and Leon Adler; University of Illinois".
It just means, as was explained to us, hopefully correctly, in very crude sum, that, it takes more juice to split H2O into Oxygen and Hydrogen, via electrolysis, with the "carbon dioxide reducing catalyst" than it does with "platinum". And, that's important insofar as it relates to balances between the various desired reactions taking place within the total electrochemical cell. There are some craniums out there, God bless 'em all, who will understand it perfectly, even if we don't.)
The cell ... wherein the coating catalyst is a metal (and wherein that metal) is indium.
(Indium isn't common, but it's not precious, either, There's about as much, it's estimated, of it on earth as there is Mercury; and, it can be obtained as a byproduct from the refining of Zinc ores. For more info, see:
Indium - Wikipedia, the free encyclopedia.)
The cell ... wherein the coating catalyst is a metal porphyrin.
The cell ... wherein the coating is a metal phthalocyanine.
(Again, if interested, see:
Porphyrin - Wikipedia, the free encyclopedia; and: Phthalocyanine - Wikipedia, the free encyclopedia.
They are well-known chemical complexes that are commercially utilized in some applications.)
The cell ... wherein the metal phthalocyanine is selected from the group consisting of iron, copper, nickel and cobalt phthalocyanine (and) wherein the primary cathode comprises a ... nickel phthalocyanine.
A method for reducing carbon dioxide in an electrolysis cell having an anode a cathode and a solid polymer electrolyte comprising; contacting the anode with a hydrogen containing material, converting said hydrogen containing material to hydrogen ions, transporting said hydrogen ions through the solid polymer electrolyte to the cathode; contacting the cathode with carbon dioxide; thereby causing the carbon dioxide to react with the hydrogen ions to form organic compounds ... .
(Yes, although they leave it as vague as possible, the "hydrogen containing material" is H2O.)
The method ... wherein the secondary catalyst is formed from a material selected from the group consisting of tin, lead, copper, zinc, cadmium, gallium, silver, gold, indium, iron, tungsten, molybdenum and carbon.
The method ... wherein the pressure of the carbon dioxide material in contact with the cathode is about 600 psi to about 900 psi.
Background and Field: The electrochemical reduction of carbon dioxide to produce organic compounds utilizing an electrolysis cell has been known for some time. Such reduction has been carried out in conventional electrolysis cells having an anode, a cathode and an electrolyte. Typically the cells are operated by passing an electric current through the anode and cathode at the same time that a fuel is brought into contact with the catalyst on the anode and a carbon dioxide containing fluid is in contact with the catalyst at the cathode.
One such process is described in U.S. Pat. No. 4,609,441 for the production of methanol ... .
(West Virginia Coal Association | Chicago Recycles CO2 to Methanol | Research & Development; "United States Patent 4,609,441 - Electrochemical Reduction of Aqueous Carbon Dioxide to Methanol; 1986; Gas Research Institute; 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. Claims: 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. Field: The invention relates to the electrochemical reduction of aqueous carbon dioxide to form methanol.")
The present invention is directed toward an improved electrolysis cell for the reduction of carbon dioxide wherein said cell comprises an anode, a solid polymer electrolyte membrane and a cathode wherein said cathode comprises a primary carbon dioxide reducing cathode having a hydrogen overvoltage greater than platinum and further contains a secondary carbon dioxide reducing cathode having a hydrogen overvoltage greater than platinum.
Further disclosed is a method of reducing carbon dioxide utilizing said improved electrolysis cell.
During the reduction of carbon dioxide in the electrolysis cell many reactions may take place at the cathode resulting in a number of possible compounds being formed.
The most prevalent reaction is the reduction of carbon dioxide to formic acid ... .
However, several other reactions may take place such as the production of methanol and formaldehyde.
While subsequent reactions may produce other organic compounds such as methanol or methane."
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We'll leave it at that. The reactions, in essence, can be driven through a sequence, that, through an initial synthesis of formic acid, from Water and Carbon Dioxide, can be made to lead subsequently to the formation of Methane and/or Methanol.
The CO2-derived Methane, we remind you, as seen for one example in:
More Standard Oil 1944 CO2 + CH4 = Hydrocarbons | Research & Development; concerning: "United States Patent 2.347.682 - Hydrocarbon Synthesis; 1944; Standard Oil Company of Indiana; Abstract: This invention relates to an improved method and means for effecting the synthesis of hydrocarbons from carbon monoxide and hydrogen. In practicing my invention I ... prefer to employ... methane (which is) mixed with such proportion of carbon dioxide and steam as to give a gas mixture having an atomic hydrogen: carbon:oxygen ratio of about 4:1:1. (The specified) reforming operation converts the methane-carbon dioxide-steam mixture into a gas consisting chiefly of hydrogen and carbon monoxide ... hereinafter referred to as ... 'synthesis' gas. The reaction products (of the synthesis gas) may be fractionated (into) high quality motor fuels";
can be reacted, "reformed", with even more Carbon Dioxide, as recovered from whatever handy source, with both the CO2-derived Methane and the additional Carbon Dioxide being converted through such reactions into a "synthesis gas" suitable for catalytic condensation into liquid hydrocarbon fuels.
The Methanol, we remind you, as seen for one example in:
Mobil Oil Coal to Methanol to Gasoline | Research & Development; concerning: "United States Patent 4,447,310 - Production of Distillates through Methanol to Gasoline; 1984; Mobil Oil Corporation; A process for producing a wide slate of fuel products from coal is provided by integrating a methanol-to-gasoline conversion process with coal liquefaction and coal gasification. The coal liquefaction comprises contacting the coal with a solvent under supercritical conditions whereby a dense-gas phase solvent extracts from the coal a hydrogen-rich extract which can be upgraded to produce a distillate stream. The remaining coal is gasified under oxidation conditions to produce a synthesis gas which is converted to methanol. The methanol is converted to gasoline by contact with a zeolite catalyst";
no matter, really, which of our abundant natural resources, whether Carbon Dioxide or Coal, we make it from, can be directly converted into Gasoline.
Finally, some relatively minimal amount of electricity is needed to drive the process of our subject herein, "United States Patent 4,921,586 - Electrolysis Cell and Method of Use", to convert Carbon Dioxide into such seemingly-desirable things as Methane and Methanol.
And, we remind you, that, as can be learned via separate references included in our reports of:
we have some significant potentials in the great, hilly and stormy heart of US Coal Country to generate a little, supplemental and CO2-free, electricity to supply the process, and the processor, disclosed by "United States Patent 4,921,586"; and, to thereby economically and efficiently convert some of our free and, some say too, abundant Carbon Dioxide into, as above, Methane and Methanol.