In a related series of reports starting more than a year ago, we documented the development, by a team of scientists employed by the former Texaco, Incorporated, of a complete family of technologies wherein Carbon Dioxide could be productively recycled into such useful things as Methanol, Methane, Formic Acid, and Formaldehyde.
We submit herein what we think will be our final report on the Carbon Dioxide recycling achievements of that particular group of Texaco scientists; and, for clarity, since their array of CO2 utilization processes is, by its volume, bewildering, we wanted to first briefly recap our several earlier reports of their work, as follows:
Texaco Recycles CO2 to Methanol & Methane | Research & Development; concerned: "US Patent 4,523,981 - Means and Method for Reducing Carbon Dioxide to Provide a Product; 1985; Inventor: Peter Ang, et. al., IL; Assignee: Texaco, Incorporated; Abstract: A process for reducing carbon dioxide to at least one useful product ... (including) formic acid (and/or) formaldehyde (and.or) methanol (and/or) methane."
Texaco Recycles More CO2 to Methanol and Methane | Research & Development; concerned: "US Patent 4,609,451 - Means for Reducing Carbon Dioxide to Provide a Product; 1986; Inventors: Anthony Sammells and Peter Ang, Illinois; Assignee: Texaco Incorporated."
Texaco Recycles Even More Co2 | Research & Development; concerned: "US Patent 4,608,132 - Means and Method for the Electrochemical Reduction of Carbon Dioxide; 1986; Inventor: Anthony Sammells; Assignee: Texaco Incorporated."
And, following, are, highly-abbreviated due to Texaco's use of arcane chemical shorthand labels, excerpts from the initial link in this dispatch, with comment appended concerning, in part, even earlier, much earlier, Texaco CO2-recycling achievements:
"United States Patent 4,545,872 - Method for Reducing Carbon Dioxide to Provide a Product
Date: October, 1985
Inventors: Anthony Sammells and Peter Ang, IL
Assignee: Texaco, Incorporated, NY
Abstract: A process and apparatus for reducing carbon dioxide to at least one useful product includes two redox couple electrolyte solutions separated by a first membrane having photosensitizers. The carbon dioxide to be reduced is provided to a second membrane which is contiguous to one of the redox couple electrolyte solutions. The second membrane has photosensitizers and a catalyst. Water provides hydrogen ions, which participate in the reduction of the carbon dioxide, via a separator. In operation both membranes are illuminated and produce excited photosensitizers which cause electron transfer from a first redox solution to a second redox solution and thence to the carbon dioxide in the second membrane thereby, in cooperation with the hydrogen ions, reducing at least some of the carbon dioxide at a surface of the second membrane to provide at least one product.
Claims: A process for reducing carbon dioxide to at least one useful product comprising the steps of:
(Providing two, specified) electrolyte solution(s) ... (and) ... separating the ... solution(s) with a first membrane having photosensitizers,
(And) providing carbon dioxide to a second membrane contiguous to the (specified) solution and having photosensitizers and a catalyst,
(And) providing water,
(And) separating the water from the carbon dioxide in a manner so that hydrogen ions, but not oxygen, may pass from the water to participate in the reduction of the carbon dioxide,
(And) illuminating both membranes so as to produce excited photosensitizers to cause electron transfer from (one) solution to the (other) thence to the carbon dioxide to ... provide at least one product.
A process as described ... which ... includes exposing both membranes to solar radiation.
A process ... in which the predominant product produced is formic acid (and/or) formaldehyde (and/or) methanol (and/or) methane.
Background and Summary: The present invention relates to photoelectrical chemical methods and apparatus for reducing carbon dioxide.
A process and apparatus for reducing carbon dioxide to at least one useful product includes two redox couple electrolyte solutions separated by a first membrane having photosensitizers. The carbon dioxide to be reduced is provided to a second membrane which is contiguous to one of the redox couple electrolyte solutions. The second membrane has photosensitizers and a catalyst. Water provides hydrogen ions, which participate in the reduction of the carbon dioxide, via a separator. In operation both membranes are illuminated and produce excited photosensitizers which cause electron transfer from a first redox solution to a second redox solution and thence to the carbon dioxide in the second membrane thereby, in cooperation with the hydrogen ions, reducing at least some of the carbon dioxide at a surface of the second membrane to provide at least one product.
The present invention as hereinbefore described is an improved photoelectrochemical method and apparatus for reducing carbon dioxide to a useful product in which the carbon dioxide is provided to a membrane having photosensitizers and catalyst."
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First of all, Texaco's specified use of "photosynthesizers", that employ the energy in "solar radiation" to convert Carbon Dioxide into such seemingly-desirable commodities as Methane and Methanol should not be surprising to you, if you have followed our posts over the past few years.
Their technology seems, in fact, to us, very similar to others about which we have previously reported, as in:
Big Oil CO2 to Methanol Photosynthesis | Research & Development; which concerned: "United States Patent 4,427,508 - Light Driven Photocatalytic Process; 1984; Assignee: Atlantic Richfield Company;
Abstract: A method for the light driven photocatalytic reduction of carbon dioxide ... to ... methanol, formaldehyde, formic acid, and methane"; and, in:
Penn State Recycles via Artificial Photosynthesis | Research & Development; concerning: "High-Rate Solar Photocatalytic Conversion of CO2 and Water Vapor to Hydrocarbon Fuels; 2008; The Pennsylvania State University; Abstract: Efficient solar conversion of carbon dioxide and water vapor to methane and other hydrocarbons".
And, it seems closely related to our US Department of Energy's "Green Freedom" CO2-recycling concept, about which we have also earlier reported. Although technical difficulties at this time prevent us from providing links to any of our previous reports concerning "Green Freedom", here is a link which should take you to one of our US Department of Energy's own expositions of it:
http://www.lanl.gov/news/
"Green Freedom (TM) A Concept for Producing Carbon-Neutral Synthetic Fuels and Chemicals
Patent Pending
Jeffrey Martin and William Kubic; Los Alamos National Laboratory
Green Freedom (TM) uses carbon-neutral power to capture and recover Carbon Dioxide from the atmosphere, split Water into Hydrogen and Oxygen, (and, to) convert Hydrogen and Carbon Dioxide into Synthetic Fuels and Chemicals."
Sounds a whole lot better than some of the other concepts our US Government's been spewing, like Cap and Trade taxation and mandated Geologic Sequestration subsidies for Big Oil's secondary petroleum scrounging, all at the expense of the consumers of Coal-based electric power, don't it?
In any case, as it happens, Texaco, as we noted in our introductory comments, and as we will document in a report to follow in coming days, actually, like a number of it's Big Oil brethren, started recycling CO2 way back in the WWII era, a phenomenon we have documented in a number of reports already, such as:
More Standard Oil 1944 CO2 + CH4 = Hydrocarbons | Research & Development; concerning: "United States Patent 2.347.682 - Hydrocarbon Synthesis; 1944; Assignee: Standard Oil Company of Indiana; This invention relates to an improved method and means for effecting the synthesis of hydrocarbons from carbon monoxide and hydrogen (which is obtained from) methane (which is) mixed with such proportion of carbon dioxide and steam as to give a gas mixture having an atomic hydrogen:carbon:oxygen ratio of about 4:1:1.(The specified) reforming operation converts the methane-carbon dioxide-steam mixture into a gas consisting chiefly of hydrogen and carbon monoxide ... hereinafter referred to as ... 'synthesis' gas."
But, again, in sum:
Carbon Dioxide, as it is produced in only a very small way, relative to natural sources of emission such as volcanoes, from our varied and productive uses of Coal, is a valuable, perhaps even a precious, raw material resource.
We can capture CO2 efficiently, even from the atmosphere itself, and, by using freely-available environmental energy, we can convert it, according to our subject process herein, of "United States Patent 4,545,872", into such seemingly-useful things as "methanol (and/or) methane".