United States Patent: 5266175
We some time ago reported on joint Swiss and Chinese development of a technology that uses "cool" dielectric plasma discharges and microwave radiation to recycle Carbon Dioxide into useful hydrocarbons.
They probably should have played it a little closer to the vest, or moved a little more assertively.
Exxon jumped on the technology, as witness this US Patent, linked above and excerpted below, with comment appended:
"United States Patent 5,266,175 - Conversion of methane, carbon dioxide and water using microwave radiation
Date: November 30, 1993
Inventor: William J. Murphy
Assignee: Exxon Research and Engineering Company
Abstract: A mixture of methane, water and carbon dioxide can be effectively converted to carbon monoxide and hydrogen by subjecting the mixture to microwave radiation in the presence of at least one plasma initiator that is capable of initiating an electric discharge in an electromagnetic field.
Claims: A method for converting methane and carbon dioxide to carbon monoxide and hydrogen which comprises:
(a) introducing a feed stream containing methane, carbon dioxide and from about 0.02 to about 20 wt% water, based on the feed stream, into a reaction zone that contains at least one plasma initiator which initiates an electric discharge in an electromagnetic field,
(b) subjecting the reaction zone to microwave radiation thereby initiating an electric discharge in said reaction zone, and
(c) ionizing the methane, carbon dioxide and water reactants whereby at least a portion of the methane and carbon dioxide are converted to carbon monoxide and hydrogen."
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We submit that "carbon monoxide and hydrogen" comprise your basic synthesis gas, "syngas", which can then be passed over a suitable Fischer-Tropsch catalyst, and, voila!, liquid hydrocarbon fuels.
We'll note, too, that this sounds very much like the "Bi-reforming" CO2 and CH4 reaction technology, about which we've earlier reported; and, it might be a step behind the more complete "Tri-reforming" process explained best so far by Penn State University; although, as we once documented, WVU has dabbled in that technology, as well.
In any case, some time after CO2 is pumped down an old oil well, under the guise of "sequestration", and after the petroleum reservoir has been inoculated with methanogenic bacteria, a mix of methane and CO2, very much like genuine natural gas, can be pumped back out, and, through the technology now, as herein, owned by Exxon, be converted into Syngas, and, then, into liquid fuels.
Of course, we must note that the methanogenic bacteria and the expense of sequestration can be avoided.
Methane can be synthesized directly from Carbon Dioxide using the Nobel-winning Sabatier technology, as now employed by NASA, and then reacted with more Carbon Dioxide in this, Exxon's, technology; or, far, far more preferably, in the probably more efficient and more productive Penn State tri-reforming technology.