First, neither Coal nor Carbon Dioxide are mentioned by name in this United States Patent, awarded to Exxon, which discloses an improved method of synthesizing hydrocarbons by gasifying Carbon with Steam.
Exxon prefers, for reasons we can only surmise, to specify "graphite" as the raw material; although they do confess that their "process will also gasify mixtures of graphite and amorphous carbon".
Further, the gasification is to be conducted on a rather intimate mixture of such Carbon and a catalytic metal, such as Nickel, Cobalt or Molybdenum.
We submit that Coke, made from Coal in a fairly standard Coke Oven, would qualify as "amorphous carbon".
But, perhaps more interestingly, Exxon does specify, as one source of such "amorphous carbon", the Carbon obtained as "coke deposited on a metal surface ... such as ... coked catalysts".
In light of that, we remind you of just one of our earlier reports, out of many from around the world detailing the potential of such technology, wherein Carbon Dioxide can be reacted, "reformed", with Methane, and made thereby to generate a synthesis gas suitable for catalytic condensation, through a number of known processes, into hydrocarbons, and now available as:
WVU CO2 + CH4 = Hydrocarbon Syngas | Research & Development | News
Therein is detailed: http://wvuscholar.wvu.edu:8881//exlibris/dtl/d3_1/apache_media/6053.pdf; "New Catalysts for Syngas Production from Carbon Dioxide and Methane; Mahesh V. Iyer; Thesis submitted to the College of Engineering and Mineral Resources at West Virginia University in partial fulfillment of the requirements for the degree of Master of Science in Chemical Engineering."
By now gratuitously, we must remind you that Methane can itself be made, via the 1912 Nobel-winning Sabatier process now being, as we've documented, further refined by NASA, from Carbon Dioxide.
And, Iyer's WVU thesis confirms our earlier reports of such technology from Switzerland, Israel and Singapore, in that it reveals "nickel catalysts" as used in the CO2-CH4 reforming reaction, "also catalyze coke formation via methane decomposition (and) efforts have been concentrated on exploring new catalysts, which are resistant to (such) carbon formation".
We have also documented that catalysts which have undergone such "coke formation" can be treated for the removal of the Coke.
Further, we have detailed "tri-reforming" technologies, such as explained best for us so far by Penn State University, as in many of our previous dispatches, wherein Steam can be added to the reaction mix of Carbon Dioxide and Methane, to forestall or to limit Coke deposition and to increase the range of hydrocarbon products which can be synthesized.
All of that relates to the Exxon technology disclosed herein.
They are reacting Steam with such Carbon, deposited on Nickel and other catalyst surfaces, as in the Methane-Carbon Dioxide bi-reforming reaction described by Iyer and WVU, and thereby generating even more hydrocarbon synthesis gas.
Brief comment follows excerpts from the initial link in this dispatch to:
"United States Patent 4,347,063 - Process for Catalytically Gasifying Carbon
Date: August, 1982
Inventor: R.D. Sherwood, NY, et. al.
Assignee: Exxon Research and Engineering Company, NJ
Abstract: Carbon is gasified with steam in the presence of a catalytic metal such as nickel by forming a dispersion of the metal on graphite ... and contacting the dispersed metal/graphite composite with steam at about 800C or higher to gasify the graphite. This process will also gasify mixtures of graphite and amorphous carbon.
Claims: A process for catalytically gasifying carbon with steam in the presence of a catalytic metal comprising Ni, Co, Mo and mixtures thereof ... .
(And) wherein said oxidizing atmosphere ... comprises (up to) 100% steam. (And) wherein said catalytic metal is Ni.
Background and Summary: This invention relates to gasifying carbon. More particularly this invention relates to catalytically gasifying carbon with steam. Still more particularly, this invention relates to catalytically gasifying carbon with steam in the presence of a catalytic metal such as nickel ... .
More particularly this invention is a process for catalytically gasifying carbon with steam in the presence of a catalytic metal comprising Ni, Co, Mo and mixtures thereof ... .
As ... stated, catalytic metals that have been found to be useful for the process of this invention are Ni, Co, Mo and mixtures thereof. Nickel and cobalt are preferred and nickel is particularly preferred as the metal.
It is understood, of course, that the process of this invention may start with a composite of the metal and graphite or graphite-containing material. Illustrative, but non-limiting examples include coke deposited on a metal surface containing one or more of said metals ... .
(Further, metal) precursors may be initially present on the graphite in the form of a metal salt or oxide such as carbonate, bicarbonate, sulfate, nitrate, etc., (and) the metal may be added to the graphite ... by any convenient means known to those skilled in the art. (Examples) include ... various wet chemistry techniques employing metal precursors such as impregnation, incipient wetness, etc., followed by drying and contacting with a reducing atmosphere at elevated temperature to insure that the deposited metal is in the reduced, metallic form. Reducing the metal may be part of the heating step of the process.
The (metal and carbon) composite is then contacted with an oxidizing atmosphere, preferably a mild oxidizing atmosphere such as CO2 or steam ... ."