China Improves CO2-to-Methane Catalysis

United States Patent Application: 0140031199

Actually, the intent of the Chinese innovation we bring to you herein is to enable the conversion of Coke Oven gas into Methane, with the constituents of Coke Oven gas including not only Carbon Dioxide, but, Carbon Monoxide and Hydrogen, as well.

However, in paragraph/item 57 of the full disclosure, we get a true indication and statement of the potentials:

"[0057] If the catalyst is not prereduced, the catalyst will be reduced in the reactor before the synthesis. The whole process lasts 5-7 days before the methane synthesis operation is conducted. The ... raw gas is the purified coke oven gas; the water vapor fed therein is in an amount of 20 volume % of the raw gas; the CO conversion rate is 83.2%; the selectivity thereof is 99.3%; the CO2 conversion rate is 70%".

And, in sum, Carbon Dioxide and Hydrogen can be fed to the reactor and catalyst specified herein, with the result being that more than two thirds of the Carbon Dioxide is converted into nearly 100 percent substitute natural gas Methane, with water, H2O, being the one byproduct.

The invention, in essence, describes a new and improved catalyst for conducting the century-old, Nobel Prize-winning Sabatier process, as summarized succinctly by Paul Sabatier, in his Nobel Prize acceptance speech, delivered December 11, 1912, as reported by the West Virginia Coal Association via: .

http://www.wvcoal.com/Research-Development/co2-solution-wins-nobel-prize-in-1912.html; "During the period 1901 to 1905 ... I showed that nickel is very suitable for the direct hydrogenation ... . Carbon monoxide and carbon dioxide are both changed immediately into methane, which can therefore be synthesized with the greatest ease".

In point of fact, Sabatier won the Nobel Prize for his work in the catalysis of hydrogenation reactions in general; and, the fact that Carbon Dioxide could be hydrogenated into Methane was then only of somewhat incidental interest.

The CO2-to-Methane Sabatier synthesis reaction itself is described and explained via:

http://www.iupac.org/publications/ci/2013/3505/Sept13_Celebrating%20Paul%20Sabatier.pdf; "At the beginning of the twentieth century, Paul Sabatier developed a process using a catalyst that reacts with carbon dioxide and hydrogen to produce methane and water. CO2 + 4H2 = CH4 + 2H2O";

with the "CH4" being the chemical formula of Methane.

Interestingly, the CO2-to-Methane reaction itself is exothermic; that is, it gives off heat energy as it proceeds. And, more recent developments of the Sabatier process, as seen for example in our report of:

West Virginia Coal Association | NASA Improves CO2 to Methane Conversion | Research & Development; concerning: "United States Patent Application 20120029095 - Sabatier Process and Apparatus for Controlling Exothermic Reaction; February 2, 2012; Inventors: Christian Junaedi, et. al.; Abstract: A Sabatier process involving contacting carbon dioxide and hydrogen in a first reaction zone with a first catalyst bed at a temperature greater than a first designated temperature; feeding the effluent from the first reaction zone into a second reaction zone, and contacting the effluent with a second catalyst bed at a temperature equal to or less than a second designated temperature, so as to produce a product stream comprising water and methane. The first and second catalyst beds each individually comprise an ultra-short-channel-length metal substrate. An apparatus for controlling temperature in an exothermic reaction, such as the Sabatier reaction, is disclosed. Government Interests: This invention was made with support from the U.S. government under U.S. Contract No. NNX10CF25P sponsored by the National Aeronautics and Space Administration. The U.S. Government holds certain rights in this invention";

are concerned with extracting that exothermic reaction heat, both so that the Methane synthesis reaction itself can proceed at good efficiency, and so that the heat energy can be utilized in other processes. One important point being that the CO2-to-Methane reaction generates all of the energy it needs to proceed, and, rather than adding energy, with attendant expense, to it to drive it forward, heat energy has to be extracted from it.

The Sabatier process does require elemental, molecular Hydrogen for the conversion of CO2 into Methane, and, as we've documented a number of times, as for one example in:

West Virginia Coal Association | USDOE and Delaware Sunshine Extracts Hydrogen from Water | Research & Development; concerning: "United States Patent Application 20130175180 - Devices and Methods for Increasing Solar Hydrogen Conversion Efficiency in Photovoltaic Electrolysis; Date: July 11, 2013; Inventors: Daniel Esposito, et. al., MD and DE; Assignee: University of Delaware; Abstract: Devices and methods for photovoltaic electrolysis are disclosed. ... Government Interests: This invention was made with Government support ... by the Department of Energy. The Government may have certain rights in this invention. Claims: A device for photovoltaic electrolysis comprising: a photovoltaic cell element configured to convert a portion of solar energy received into electrical energy, the photovoltaic cell element configured to pass another portion of the solar energy; and an electrolysis compartment including an aqueous electrolyte positioned to receive the other portion of the solar energy passing through the photovoltaic cell element, the electrolysis compartment including electrodes electrically connected to receive the electrical energy produced by the photovoltaic cell element. This invention relates generally to electrolysis, and more particularly to devices and methods for increasing solar hydrogen conversion efficiency in photovoltaic electrolysis. Photovoltaic (PV) electrolysis allows the generation of hydrogen gas (H2) and oxygen gas (O2) from water using solar energy";

we're getting pretty good at extracting Hydrogen from Water, H2O, in processes driven by freely-available environmental energy.

And, as demonstrated by the United States Navy in our report of:.

West Virginia Coal Association | US Navy 2008 CO2 to Synfuel | Research & Development; concerning: "United States Patent 7,420,004 - Producing Synthetic Liquid Hydrocarbon Fuels; 2008; Assignee: The USA, as represented by the Secretary of the Navy; Abstract: A process for producing synthetic hydrocarbons that reacts carbon dioxide, obtained from seawater or air, and hydrogen obtained from water, with a catalyst in a chemical process such as reverse water gas shift combined with Fischer Tropsch synthesis. The hydrogen is produced by ... ocean thermal energy conversion, or any other source that is fossil fuel-free, such as wind or wave energy. The process can be either land based or sea based";

we can use abundant ocean water as the source of that Hydrogen, as opposed to increasingly scarce and uncontaminated fresh water, the conservation of which is becoming a subject of growing concern to environmentalists.

With apologies for the long introduction, following are excerpts from the initial link in this dispatch, demonstrating yet again that Carbon Dioxide can be converted into substitute natural gas Methane:

"United States Patent Application 20140031199 - Methane Synthesis Catalyst Preparation Method

METHANE SYNTHESIS CATALYST PREPARATION METHOD AND CATALYST PRECURSOR - XINDI ENERGY ENGINEERING TECHNOLOGY CO., LTD

January 30, 2014

Inventors: Junshi Chang, et. al., Beijing

Assignee: Xindi Energy Engineering Technology Company, Ltd., China

(Again, although we're highlighting the demonstrated potentials here for the catalyzed conversion of a mixed gas of Carbon Dioxide and Hydrogen into Methane, which is a component of the overall process, the invention is actually concerned with the conversion of Coke Oven gas into Methane, as a way to utilize a by-product arising from China's rather extensive coking and steel-making industries. As can be learned via:

http://www.xindny.com/english/results-194.html; "Coke Oven Gas to Liquefied Natural Gas Project";

"Xindi Energy Engineering", the owner of the technology being disclosed via "United States Patent Application 20140031199 - Methane Synthesis Catalyst Preparation Method", is actively involved in establishing and operating at least five projects, wherein Coke Oven gas is recovered and converted into Methane, or, into a substitute "Liquefied Natural Gas".

And, as we documented for you nearly five years ago, in a somewhat general discussion:

West Virginia Coal Association | Coke Oven Gas to Synfuel | Research & Development; concerning, for instance and only in part: "The 120 000 t/a methanol project based on coke oven gas designed by the Second Design Institute of Chemical Industry started production in Kingboard (Hebei) Coking Co., Ltd. on Sept. 5. The product reached the standard for AA-grade products in the United States. The capacity of this unit is 40 000 t/a higher than the first methanol unit based on coke oven gas in China complete in Qujing, Yunnan province in December 2004";

China does view byproduct Coke Oven gas as a valuable raw material resource. By extension, in conjunction with efficient Hydrogen generation technologies, we could, and should, begin to look at Carbon Dioxide alone in exactly that way.)

Abstract: The present invention relate to a methane synthesis catalyst preparation method, comprising a preparation step for a catalytic body and a prereduction step. The prereduction step comprises: calcining the catalytic body to form a nickel aluminate spinel-containing catalyst precursor; and prereducing the catalyst precursor to acquire the methane synthesis catalyst. The catalyst prepared in the preparation method can be used in high-temperature and high liquid-to-gas ratio conditions, shows performance stability, and obviates the need for a further step of high-temperature reduction during vehicle operation. Also provided is the methane synthesis catalyst precursor. The catalyst precursor contains nickel aluminate spinel.

(Many, perhaps most, people might associate the above "spinel" with jewelry or gemstones; and, thus, expense. In one sense that's true, but not here. In mineralogy, the term "spinel" also refers to any of a group of minerals that are just oxides of magnesium, ferrous iron, zinc, or manganese with a particular crystal structure. There isn't anything rare or too expensive being specified here.)

Claims: A method for preparing a methane synthesis catalyst, comprising a preparation step for a catalytic body containing nickel nitrate, a aluminium compound and a magnesium compound and a prereduction step, wherein the catalytic body is produced by the mixing-precipitation method or the coprecipitation method; the prereduction step comprises calcining the catalytic body at 700-1100 C to form a nickel aluminate spinel-containing catalyst precursor; and prereducing the catalyst precursor at 700-1000 C. to acquire the methane synthesis catalyst (and) wherein the preparation step for a catalytic body by the mixing-precipitation method comprises spray drying a slurry containing nickel nitrate, aluminium hydroxide and light magnesium oxide (and) wherein the preparation step for a catalytic body by the coprecipitation method comprises neutralizing with an aluminium-containing precipitator a suspension or solution containing nickel nitrate and a magnesium compound selected from the group consisting of magnesium nitrate and light magnesium oxide.

A methane synthesis catalyst precursor ... wherein the catalyst precursor comprises a nickel aluminate spinel (and) wherein the nickel aluminate spinel is in a mass content of 5-75% in the precursor.

(We're condensing the "Claims" section in the extreme, since it deals only with the preparation of the catalyst. The thing to keep in mind is that this is a catalyst that promotes the synthesis of Methane from Carbon Dioxide.)

Technical Field: The present invention relates to the field of methanation of oxycarbides, in particular to a methane synthesis catalyst preparation method and catalyst precursor.

(We believe by "oxycarbide" that they're referring to Carbon Dioxide and Carbon Monoxide, although someone knowledgeable we consulted suggested the term would be better applied to CO or CO2 as they might be incorporated as chemical units in a more complex compound.)

Thus, one aspect of the present invention is to provide a method for preparing a methane synthesis catalyst.

The term 'coke oven gas' represents an inflammable gas produced together with coke and tar product after several bituminous coals are formulated into oven coal and dry distilled at high temperatures in a coke oven, and is a by-product of coking industry.

(We'll note that Methane is already, typically, a component of Coke Oven gas. And, the purpose of the invention is to convert the remaining Carbon Oxides and Hydrogen into Methane, as well.)

The prereduced catalyst is ... activated at 250 C with coke oven gas, then heated to 650 C, wherein the reaction (proceeds under specified conditions of temperature and pressure, The) raw gas is the purified coke oven gas; the water vapor fed therein is in an amount of 20 volume % of the raw gas; the CO conversion rate is 83.2%; the selectivity thereof is 99.3%; the CO2 conversion rate is 70%."

-------------------------

In condensed sum, Coke Oven Gas aside, we can pass a blend of Carbon Dioxide and Hydrogen over the catalyst disclosed herein, and "70%" of the Carbon Dioxide will be converted into Methane, which is, in essence, at "99.3%", the only reaction product, aside from H2O.

We submit that the un-reacted Carbon Dioxide, rather than being recycled into the process of "United States Patent Application 20140031199 - Methane Synthesis Catalyst", to make more Methane, could, instead, be directed to an additional process, like that seen for one example in our report of:

West Virginia Coal Association | Saudia Arabia CO2 + Methane = Hydrocarbons + Syngas | Research & Development; concerning: "United States Patent 7,355,088 - Process for Producing Benzene, Ethylene and Synthesis Gas; 2008; Inventors: Agaddin Mamedov, et. al., Saudi Arabia; Assignee: Saudi Basic Industries Corporation, Riyadh; Abstract: Process for producing benzene, ethylene and synthesis gas, comprising the steps of: i) introducing a starting gas flow comprising methane and carbon dioxide into a reactor; ii) oxidizing the methane in the reactor at certain reactor conditions optionally using a first catalytic material and/or and additional oxidant; and: iii) removing a product gas flow comprising benzene, ethylene and synthesis gas from the reactor";

and be reacted with some of the product Methane, and be made thereby to form some higher hydrocarbons, "benzene, ethylene", and hydrocarbon "synthesis gas", which can be further reacted, as via for example the nearly ancient Fischer-Tropsch synthesis, and be transformed thereby into even more hydrocarbons.

We note that the process of our subject, "United States Patent Application 20140031199 - Methane Synthesis Catalyst Preparation Method" is, as seen in our recent report of:

West Virginia Coal Association | Sunlight Converts CO2 into Methane | Research & Development; concerning: "United States Patent 8,617,375 - Method For Reducing Carbon Dioxide; December 31, 2013; Assignee: Panasonic Corporation, (Japan); (It) is an object of the present invention to provide a method for reducing carbon dioxide using a highly-durable catalyst that is capable of reducing CO2 at an overvoltage equal to or lower than overvoltages required for conventional catalysts to produce highly useful substances (such as formic acid (HCOOH), methane (CH4), ethylene (C2H4), and ethane (C2H6))";

just another in an extensive series of demonstrations of a now-apparently straightforward fact:

Carbon Dioxide - - as it arises in only a small way, relative to some all-natural and un-taxable sources of it's emission, such as the Earth's inexorable processes of planetary volcanism, from our economically essential use of Coal in the generation of truly abundant and truly affordable electric power - - is a valuable raw material resource.

It could be used to carry us into an environmentally and economically better era of domestic self-sufficiency in our supply of gaseous and liquid hydrocarbons

And, it is far, far past time the truth of that, that fact, was openly and publicly reported to us all.