WV Coal Member Meeting 2024 1240x200 1 1

Chicago Converts CO2 into Methane and Ethylene

United States Patent: 4897167

We've made quite few reports to you by now documenting the development, by Chicago's former Gas Research Institute, of technologies whereby Carbon Dioxide and Water can be electro-chemically and/or thermo-chemically converted into hydrocarbon fuels, as seen, for one example, in our report of:

Chicago CO2 + H2O = Hydrocarbons | Research & Development | News; concerning: "United States Patent 4,756,806 - Synthesis of Gaseous Fuels from Water and Carbon Dioxide; 1988; Assignee: Gas Research Institute, Chicago; Abstract: A hybrid thermoelectrochemical process cycle for production of gaseous fuels from cycle inputs of water and carbon dioxide ... (and, which cycle produces) oxygen, gaseous fuel selected from the group consisting of methane, hydrogen, carbon monoxide, and mixtures thereof ... . A two step hybrid process cycle ... wherein said inorganic oxidizer comprises principally water (or)  principally carbon dioxide and said gaseous fuel comprises principally methane". 

 

As in the above "United States Patent 4,756,806 - Synthesis of Gaseous Fuels from Water and Carbon Dioxide", the primary hydrocarbon specified by the Gas Research Institute to made from CO2 is substitute natural gas Methane.

There are, of course, other light hydrocarbon constituents of natural gas in addition to "Methane"; and, as seen in our report of: 

Chicago Electricity-driven CO2 and Hydrogen to Hydrocarbons | Research & Development | News; concerning: "United States Patent 4,959,131 - Gas Phase CO2 Reduction to Hydrocarbons; Date: September, 1990; Inventors: Ronald Cook and Anthony Sammells, IL; Assignee: Gas Research Institute, Chicago; Abstract: A process and apparatus for gas phase electrochemical reduction of CO2 and/or CO to hydrocarbons at ambient temperatures. The process is carried out by passing an electrical current between a cathode in contact with one side of a hydrogen ion conducting solid polymer electrolyte and an anode in ionic communication with the opposite side of the solid polymer electrolyte. In one embodiment, the anode material may be in contact with the opposite side of the hydrogen ion conducting solid polymer electrolyte, and in another embodiment, an anode may be separated from the opposite side of the solid polymer electrolyte by an aqueous inorganic salt solution. At least one of CO2 and CO are passed in contact with the cathode and hydrogen ions passing through the solid polymer electrolyte reduce at least a portion of the CO2 and CO to gaseous hydrocarbon products such as CH4 (Methane) and C2H4 ("Ethylene", aka "ethene"; a colorless flammable gas) at the solid polymer electrolyte/cathode interface";

the Gas Research Institute developed Carbon Dioxide utilization technologies which could synthesize some of those other light hydrocarbons, specifically "Ethylene", "C2H4", as well.

And, herein, we submit yet another Gas Research Institute technology, slightly precedent to the above "United States Patent 4,959,131 - Gas Phase CO2 Reduction to Hydrocarbons", for synthesizing not just Methane, but Ethylene, too, from Carbon Dioxide.

We are submitting report of this earlier development at this time since, as will be seen in reports to follow, another company about whom we've been reporting, Liquid Light, Inc. of New Jersey, as seen for one example in:

New Jersey Consumes CO2 in the Synthesis of Polymers | Research & Development | News; concerning: "United States Patent 8,691,069 - Method and System for the Electrochemical Co-Production of Halogen and Carbon Monoxide for Carbonylated Products; April 8, 2014; Assignee: Liquid Light, Inc., NJ; Abstract: The present disclosure is a system and method for producing a first product from a first region of an electrochemical cell having a cathode and a second product from a second region of the electrochemical cell having an anode. The method may include a step of contacting the first region with a catholyte including carbon dioxide and contacting the second region with an anolyte including a recycled reactant.
The method ... wherein the ... product includes one of isocyanate, methyl isocyanate, butyl isocyanate, phenyl isocyanate, diisocyanate, methylene-diphenylisocyanate, phenyl-diisocyanate, hexamethylene-diisocyanate, toluene-diisocyanate (and, etc.). ...The method ... wherein the cathode and the anode are separated by an ion permeable barrier (and) wherein the ion permeable barrier includes one of a polymeric or inorganic ceramic-based ion permeable barrier. ... The present disclosure generally relates to the field of electrochemical reactions, and more particularly to methods and/or systems for electrochemical co-production of halogen and carbon monoxide for use in carbonylation reactions. Summary: A mechanism for mitigating emissions is to convert carbon dioxide into economically valuable materials such as fuels and industrial chemicals. If the carbon dioxide is converted using energy from renewable sources, both mitigation of carbon dioxide emissions and conversion of renewable energy into a chemical form that can be stored for later use will be possible";

have been developing an extensive array of productive Carbon Dioxide utilization technologies, most of them descending immediately from, or directly related to, CO2-recycling work more recently performed, as seen for one example in:

Princeton University March, 2014, CO2 to Methanol | Research & Development | News; concerning: "United States Patent 8,663,447 - Conversion of Carbon Dioxide to Organic Products; 2014; Inventors: Andrew Bocarsly, NJ, and Emily Barton Cole, TX; Assignee: Princeton University, NJ; Abstract: The invention relates to various embodiments of an environmentally beneficial method for reducing carbon dioxide. The methods in accordance with the invention include electrochemically or photoelectrochemically reducing the carbon dioxide in a divided electrochemical cell that includes an anode, e.g., an inert metal counterelectrode, in one cell compartment and a metal or p-type semiconductor cathode electrode in another cell compartment that also contains an aqueous solution of an electrolyte and a catalyst of one or more substituted or unsubstituted aromatic amines to produce therein a reduced organic product. Government Interests: This invention was made with United States government support from National Science Foundation Grant No. CHE-0616475. The United States Government has certain rights in this invention. Claims: An environmentally beneficial method of producing methanol by electrochemical reduction of any available source of carbon dioxide, which comprises: providing a divided electrochemical cell comprising an anode in a first cell compartment and a cathode in a second cell compartment that also contains a catalyst which is one or more of a substituted or unsubstituted aromatic heterocyclic amine selected from the group consisting of a pyrazine, a pyridazine, and a pyrimidine, both compartments containing an aqueous solution of an electrolyte; providing carbon dioxide from an existing source into the second cell compartment; and electrochemically reducing the carbon dioxide in the second cell compartment to produce methanol";

in the Princeton University lab of Professor Andrew Bocarsly. However, Liquid Light, as we will see, has created a veritable barrage of additional electrochemical processes for the consumption and productive utilization of Carbon Dioxide; and, most, if not all, of them make reference to the CO2-recycling work accomplished a few decades ago at the Gas Research Institute in Chicago as directly precedent art. And, among the Gas Research Institute CO2-utilization technologies most frequently cited by Liquid Light, in addition to the above "United States Patent 4,959,131 - Gas Phase CO2 Reduction to Hydrocarbons", is one about which we have not yet reported, which is slightly precedent to "USP 4,959,131", but which also specifies Ethylene, C2H4, as one of the key products, in addition to Methane, which can be directly synthesized from Carbon Dioxide and Water. 

Comment follows excerpts from the initial link in this dispatch to:

"United States Patent 4,897,167 - Electrochemical Reduction of CO2 to CH4 and C2H4

Electrochemical reduction of CO2 to CH4 and C2 H4 - Gas Research Institute

Date: January 30, 1990

Inventors: Ronald Cook, et. al., Illinois

Assignee: Gas Research Institute, Chicago

Abstract: A process for electrochemical reduction of CO2 to CH4 and C2H4 providing both high current densities and high Faradaic efficiencies. The process is carried out in an electrochemical cell wherein copper is electrodeposited in situ on the cathode surface making freshly deposited copper available for the electrochemical reduction. Faradaic efficiencies of about 75 to about 98 percent for production of CH4 and C2H4 are obtained. 

Claims: A process for electrochemical reduction of CO2 to CH4 and C2H4 at both high current densities and high Faradaic efficiencies in an electrochemical cell comprising an anode and a cathode in contact with an electrolyte, said process comprising: passing a current between said anode and said cathode; electrodepositing Cu ions from an electrolyte comprising an aqueous inorganic salt solution in which CO2 is soluble and Cu ions forming deposited uniformly granular Cu on a highly polished cathode surface in situ; passing CO2 through said electrolyte and contacting said cathode surface; reducing at least a portion of said CO2 to CH4 and C2H4 at said in situ deposited Cu cathode surface; removing gaseous products comprising CH4 and C2H4 form said electrolyte. 

A process ... wherein said inorganic salt is in a concentration of about 0.3 to about 0.8 Molar and said electrolyte is at a pH of about 4 to 9 (and) wherein said electrolyte inorganic salt is selected from the group consisting of KHCO3, NaHCO3, KCl, KClO4, KOH, KBF4, K2CO3, K2SO4, KHSO4 KH2PO4 and K2HPO4. 

(As will be seen, among the Liquid Light improvements on this CO2-recycling technology are dramatic changes to the composition of the "electrolyte(s)" which enable the more efficient electrolytic transformation of Carbon Dioxide supplied to the electrolyte, along with Hydrogen from H2O, into other compounds.)

A process ...wherein said Cu ions are supplied by a copper compound selected from the group consisting of CuSO4, Cu(NO3)2, Cu(BrO3)2 and Cu(BO2)2.

(It seems as if almost any water-soluble Copper compound will serve.)  

A process ... wherein said cathode comprises a metal substrate selected from the group consisting of glassy carbon, copper, and metals of the 3d, 4d and 5d transition series.

(Don't be snowed by the need for "metals of the 3d, 4d and 5d transition series". There are a lot of available and affordable options. For more than you likely really want to know about it, have a look at:

http://textbook.s-anand.net/ncert/class-xii/chemistry/8-the-d-and-f-block-elements.)

A process .. wherein said cathode comprises a metal substrate selected from the group consisting of glassy carbon and copper (and) wherein said electrolyte is separated by an H3O ion passing separator into an anolyte and a catholyte, said electrodepositing Cu ions forming granular Cu on said cathode surface in situ and said passing CO2 and contacting said cathode surface taking place in said catholyte.

(The "H3O" is just the ion of Water, H2O, known as "hydronium", according to references we've looked at.  And, although an "H3O ion passing separator" sounds like pretty sophisticated stuff for back in 1990, as can be learned via:

http://www.remco.com/ix.htm; they are known, understood, and available today, in the form of what are known as "ion exchange resins", which are often used in fuel cells, apparently.)

A process ... wherein said electrolyte is maintained at a temperature about 0 to about 30 C (and) wherein said electrolyte is maintained at a temperature about 0 to about 10 C for preferential CH4 production (and) wherein said electrolyte is maintained at a temperature about 20 to about 30 C for preferential C2H4 production. 

(The above is interesting to note. We can make Methane or Ethylene preferentially from CO2 and H2O by simply varying the process temperature within ranges that, really, could be described as moderate.)

A process ... wherein said granular Cu is continuously formed on said cathode surface to provide fresh in situ deposited Cu (and) wherein said granular Cu is intermittently formed on said cathode surface to provide fresh in situ deposited Cu (and) wherein said granular Cu cathode surface is periodically regenerated by anodic polarization followed by said electrodepositing Cu ions forming granular Cu on said cathode surface in situ to provide fresh in situ deposited Cu. 

In a process for electrochemical reduction of CO2 to CH4 and C2H4 at both high current densities and high Faradaic efficiencies in an electrochemical cell comprising an anode and a cathode in contact with an electrolyte, wherein the improvement in the cathode half cell comprises: electrodepositing Cu ions form an electrolyte comprising an aqueous inorganic salt solution in which CO2 is soluble and Cu ions forming in situ deposited uniformly granular Cu on a highly polished cathode surface; passing CO2 through said elctrolyte and contacting said in situ deposited Cu cathode surface; reducing at least a portion of said CO2 to CH4 and C2H4 at said in situ deposited Cu cathode surface.

Summary: The process of this invention provides electrochemical reduction of CO2 to CH4 and C2H4 at both high current densities and high Faradaic efficiencies.

Faradaic yields of hydrocarbons by the electrochemical reduction of CO2 according to this invention can be in order of 98 percent at 8.3 mA/cm2 and about 79 percent at an increased current density of 25 mA/cm2.

We have found that to obtain such high Faradaic yields at high current densities by the electrochemical reduction of CO2, it is important to provide a cathode surface of in situ deposited uniformly granular copper over the entire cathode substrate. Suitable in situ copper deposition may be achieved in any suitable electrolytic cell wherein the cathode substrate is a suitable electrically conducting metal substance upon which copper can be deposited immersed in an aqueous inorganic salt electrolyte in which CO2 is soluble and comprising a copper cation supply material which will form copper cations under electrolytic cell operating conditions ... . In preferred embodiments, glassy carbon is a suitable cathode substrate material, KHCO3 is a suitable aqueous electrolyte, and CuSO4 is a suitable copper cation supply material. Cathode surface copper can be continuously or intermittently deposited during the CO2 reduction process or the cathode copper surface can be periodically regenerated ... . 

The process for electrochemical reduction of CO2 to CH4 and C2H4 at high current densities and high Faradaic efficiencies may be conducted in any suitable electrochemical cell configuration wherein the cell comprises an anode and a cathode in contact with an electrolyte and means for passing a current between the anode and cathode. The anode may be any suitable electrically conducting metal substance suitable for effective electrolytic cell operation, such as platinum, nickel, lead, glassy carbon, Ebony and titanium, preferably nickel, glassy carbon and lead. Suitable cathodes include any electrically conducting metal substrate upon which copper may be deposited. Suitable cathode substrates include glassy carbon, copper and metals of the 3d, 4d and 5d transition series, preferably glassy carbon and copper. To obtain even and complete electrode position of copper granules on the surface of the cathode, it is preferred that the cathode surface be highly polished by any suitable means known to the art, such as by very fine, 0.05 micron, alumina paste. 

Any aqueous inorganic salt solution in which CO2 is soluble and which does not provide interfering ions may be used as an electrolyte, such as aqueous solutions of KHCO3, NaHCO3, KCl, KClO, KOH, KBF4, K2CO3, K2SO4, KHSO4, KH2PO4, K2HPO4, preferably KHCO3 or NaHCO3 in concentrations (as specified) at pH preferably of about 4 to about 9. However, ammonia containing compounds and tetraalkyl cations must be avoided. The electrolyte also comprises a suitable copper ion supply material, which is any inorganic copper salt which will form copper cations under electrolytic cell operating conditions without interfering with the anodic reaction, such as CuSO4, Cu(NO3)2, Cu(BrO32 and Cu(BO2)2.

The electrolyte has a high content of dissolved CO2 and is preferably saturated with CO2"

---------------------------. 

Again, we can efficiently synthesize Methane and Ethylene from Carbon Dioxide and Water in an electrochemical cell and process as, disclosed herein by the Gas Research Institute and as confirmed by the United States Government.

Aside from the value of substitute natural gas Methane, the Ethylene might be of particular interest, since it is the raw material from which Polyethylene, which some references indicated is the most widely-used polymer in the world.

We here don't, in fact, know if it is used more than any other polymer; but, the worldwide demand is truly huge. And, it's important to note that any Carbon Dioxide used and consumed, as via the process of our subject herein, "United States Patent 4,897,167 - Electrochemical Reduction of CO2 to CH4 and C2H4", in the synthesis of Ethylene that was then converted into Polyethylene, would remain in that polymer essentially forever; where it would be productively, chemically, and profitably "sequestered".

As far as where we might get the Carbon Dioxide with which to saturate the "electrolyte", as per our concluding excerpt above, we have documented and will further document how it can be extracted from either the flue gases of industrial processes or the atmosphere itself. However, if we wish to start with a nearly-pure stream of Carbon Dioxide to convert into gaseous hydrocarbons, like the natural gas constituents Methane and Ethylene via the process of our subject herein, "United States Patent 4,897,167 - Electrochemical Reduction of CO2 to CH4 and C2H4", then we remind you that, as seen in our report of:

USDOE 2014 Coal to Liquid Hydrocarbons + Pure CO2 | Research & Development | News; concerning: "United States Patent 8,674,152 - Coal Liquefaction by Base-Catalyzed Hydrolysis with CO2 Capture; Date: March 18, 2014; Inventor: Xin Xiao, Georgia; Assignee: Savannah River Nuclear Solutions, LLC, South Carolina (USDOE Savannah River National Laboratory); Abstract: The one-step hydrolysis of diverse biomaterials including coal, cellulose materials such as lumber and forestry waste, non-food crop waste, lignin, vegetable oils, animal fats and other source materials used for biofuels under mild processing conditions which results in the formation of a liquid fuel product along with the recovery of a high purity CO2 product is provided";

we could obtain a nearly pure stream of Carbon Dioxide as a valuable byproduct from a process developed by our United States Department of Energy, wherein Coal and renewable, Carbon-recycling "biomaterials" are converted together rather directly into "a liquid fuel product".

In any case, the electrochemical processes of "US Patent 4,897,167 - Electrochemical Reduction of CO2 to CH4 and C2H4", and of it's related Gas Research Institute technologies, has, as we will see in reports to follow, served as a foundation upon which additional and even more efficient CO2 consumption and utilization technologies - - resulting in the production of similar hydrocarbon species and relying on more advanced electrolyte solutions which result in even greater process efficiencies - - have been much more recently developed by the New Jersey company, Liquid Light, Inc., which itself was founded on the Carbon Dioxide utilization efforts begun, and the Carbon Dioxide utilization technologies established, in the Princeton University lab of Professor Andrew Bocarsly.