United States Patent: 3865924

We have many times documented the rather extraordinary body of Carbon Dioxide recycling technology that had been developed by the former Gas Research Institute and Institute of Gas Technology, in Chicago, Illinois; both of which merged, a little more than a decade ago, to form the Gas Technology Institute.

For more info, see:

Gas Technology Institute - Wikipedia, the free encyclopedia; and: Gas Technology Institute - Home.

Our reports on their CO2 utilization technologies have included, for instance:

Chicago Recycles CO2 to Methane | Research & Development; concerning their: "United States Patent 4,609,440 - Electrochemical Synthesis of Methane; 1986; Assignee: Gas Research Institute; A method is described for electrochemically reducing carbon dioxide to form methane"(CH4); and:

West Virginia Coal Association | Chicago CO2 + Methane = Hydrocarbons | Research & Development; concerning their: "United States Patent 5,064,733 - Electrochemical Conversion of CO2 and CH4 to C2 Hydrocarbons; 1991; Assignee: Gas Research Institute; A solid electrolyte electrochemical cell and process for concurrent gas phase electrocatalytic oxidative dimerization of methane at one side of the solid electrolyte and reduction of carbon dioxide to gaseous hydrocarbon products at the opposite side of the solid electrolyte"; and:

Chicago Recycles CO2 to Methanol | Research & Development; concerning their: "United States Patent 4,609,441 - Electrochemical Reduction of Aqueous Carbon Dioxide to Methanol; 1986; Assignee: Gas Research Institute; A method of producing methanol from carbon dioxide is set forth".

Given that the good people at the Gas Research Institute and the Institute of Gas Technology were obviously intent on demonstrating the unpopular fact that Carbon Dioxide is a valuable raw material resource from which we can synthesize any number of badly needed hydrocarbons, it stands to reason that they would have put a little thought, at least, into how they could go about efficiently acquiring some CO2, with which to make such seemingly-desirable products as "Methane", "Methanol" and "Hydrocarbons".

And, indeed, they did. As seen in excerpts from the initial link in this dispatch to:

"United States Patent 3,865,924 - Process for Regenerative Sorption of CO2

Date: February, 1975

Inventors: Dimitri Gidaspow and Michael Onischak, Chicago

Assignee: Institute of Gas Technology, Chicago

Abstract: A process and apparatus for the removal of carbon dioxide from a gaseous stream, wherein the CO2 content ranges from trace amounts up to 50 mole percent, and for subsequent transfer to another gas stream by thermal regeneration. A special composition comprising a finely ground mixture of potassium carbonate and alumina, which has synergistic properties, is used as the absorbent. In a preferred apparatus embodiment, the mixture is incorporated into a rotary regenerative wheel.

(Yes, "trace amounts" of CO2 means that we could apply this to atmospheric air. We could install it any place where one form of environmental energy or another is present in some abundance, and use that environmental energy to drive the process. We would not have to install parasitic Carbon Dioxide capture facilities at our Coal-fired power plants and thereby decrease the efficiency of those plants.)

Claims: A method of removing CO2 from a gaseous stream comprising the steps of: 

a. passing a CO2 -containing inlet gas stream into contact with a synergistic sorbent composition of finely divided, particulate alkali metal carbonate and alumina, said alumina and carbonate being separate discrete particles and having been ground together to provide such sorbent, to sorb CO2 thereinto and convert said carbonate to bicarbonate, 

b. maintaining said sorbent composition in hydrated form, thereby to remove CO2 from said gases stream; and:

c. regenerating said sorbent composition by supplying heat to reconvert said bicarbonate to said carbonate form while evolving CO2 therefrom, without forming a crust over said sorbent.

(Since we need heat, electrical resistance heating powered by electricity derived from wind or hydro would work just fine; and, we've previously documented those Coal Country potentials for you. Another option might be geothermal heat energy, which, as seen in:

West Virginia Coal Association | Another Energy Bonanza for Coal Country | Research & Development; concerning: "West Virginia Geothermal; A Large Green Energy Source Beneath Northeastern West Virginia; Southern Methodist University, 2010; New research produced by Southern Methodist University's Geothermal Laboratory, funded by a grant from Google.org, suggests that the temperature of the Earth beneath the state of West Virginia is significantly higher than previously estimated and capable of supporting commercial baseload geothermal energy production";

could be extracted in Coal Country and used directly to drive the needed "regenerating" process.)

2. A method of CO2 removal ... which includes the added steps of: 

a. passing an exhaust gas stream into contact with said sorbent when said sorbent is substantially in the bicarbonate form, 

b. maintaining said heat until said bicarbonate is regenerated to carbonate and said evolved CO2 is delivered to said exhaust gas stream. 

A method of CO2 removal ... wherein said process is maintained in a continuous cyclic fashion, said passing of inlet gases being in the sorption half of said cycle and said passing of exhaust gases being in the desorption regeneration half of said cycle. 

A method of CO2 removal ... wherein the inlet gas stream contains up to about 50 percent, by volume, CO2. 

A method of CO2 removal ... wherein said carbonate comprises from 5-75 percent, by weight of the total composition, and said alumina comprises from 95-25 percent, by weight of said total composition. 

A method of CO2 removal ... wherein said alkali metal carbonate is potassium carbonate. 

A method of CO2 removal ... wherein said carbonate is admixed, in powdered form, in (specified particle sizes) with said alumina, and said alumina has a (specified) surface area ... . 

A method of CO2 removal ... wherein said sorbent is supported on a filamentous carrier ... selected from wire mesh or fibrous materials capable of withstanding temperatures of over 165C (such as) cellulose, plastic, and mixtures thereof.


Description: This invention relates to a process and apparatus for the removal of carbon dioxide from a gaseous stream, where the CO2 content ranges from trace amounts to 50 mole percent. More specifically, the invention involves a special CO2 absorbent mixture, and apparatus particularly adapted for the rapid, continuous and repeated regeneration of the mixture material for continuous CO2 removal. 

A particularly suitable use of the invention is removal of CO2 from air ... .

Background: The removal of carbon dioxide from various gases is important in many areas
It is also desirable to recover carbon dioxide from industrial gas process streams where the carbon dioxide is produced in large amounts and it is desirable to concentrate and recover the carbon dioxide for use ... .

For example, carbon dioxide is produced in large amounts by fermentation of carbohydrate materials and sugars, in the manufacture of lime and cement, and in the combustion of coal ... and natural gas.

Summary: We have discovered that a mixture of finely divided alkali metal carbonate, e.g. potassium carbonate, and alumina sorbs CO2 faster than pure carbonate alone. A stream of gas containing carbon dioxide and water vapor is passed over a layer of the adsorbent mixture. The sorption of CO2 by the composition of our invention requires water to proceed. If no water is present in the gas stream, it must be added to form the hydrate of potassium carbonate either before CO2 is introduced or simultaneously with the introduction of the CO2.

(The) potassium carbonate hydrate ... reacts with the CO2 to form potassium bicarbonate.

(And,) subsequently, the mixture is heated and the potassium carbonate is regenerated by decomposing the potassium bicarbonate thereby giving up CO2."


The "potassium carbonate" is then recycled to absorb more Carbon Dioxide; and, the CO2 which has been "given up" is then available to be utilized in another process, perhaps one like that described in another Institute of Gas Technology process, like that seen in:

Chicago Converts CO2 to Methane | Research & Development; "US Patent 3,766,027 - Method and Apparatus for CO(2) Conversion to Methane; 1973; Assignee: Institute of Gas Technology, Chicago; Abstract: A process of fixation and conversion of carbon dioxide from the atmosphere or other sources to produce methane and oxygen";

and, the Methane could then be used in another process, like that disclosed in our report of:

Exxon 2010 CO2 + Methane = Liquid Hydrocarbons | Research & Development; concerning: "United States Patent 7,772,447 - Production of Liquid Hydrocarbons from Methane; 2010; Assignee: ExxonMobil, Houston; A process for converting methane to higher 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";

wherein it could be reacted with even more Carbon Dioxide, as efficiently collected by the process of our subject herein, "United States Patent 3,865,924 - Process for Regenerative Sorption of CO2", with both being converted through such reaction into even more "hydrocarbons".

As we've said many times previously:

Carbon Dioxide, as it arises in only a small way relative to natural sources of emission, such as volcanoes, from our productive and essential use of Coal in the generation of electrical power, is a valuable raw material resource.

We can reclaim Carbon Dioxide efficiently, even from the atmosphere itself, and, through a number of established processes reviewed and certified by our United States Government, convert that Carbon Dioxide into such seemingly-desirable things as "Methane", "Methanol" and various other "Hydrocarbons".

West Virginia Coal Association - PO Box 3923 - Charleston, WV 25339 | 304-342-4153 | website developed by brickswithoutstraw