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A hstrnctIt has been understood that production of hydrogen from fossil and carbonaceous fuels with reduced CO, emission to the atmosphere is key to the production of hydrogen-rich fuels for mitigating the CO, greenhouse gas climate change problem. The conventional methods of hydrogen production fi-om fossil fuels (coal, oil, gas and biomass) include steam reforming and water gas shift mainly of natural gas (SRM). In order to suppress CO, emission from the steam reforming process, CO, must be concentrated and sequestered either in or under the ocean or underground (in aquifers, or depleted oil or gas wells). Up to about 40% of the energy is lost in this process. An alternative process is the pyrolysis or the thermal decomposition of methane, natural gas (TDM) to hydrogen and carbon. The carbon can either be sequestered or sold on the market as a materials commodity or used as a fuel at a later date under less severe CO, restraints. The energy sequestered in the carbon amounts to about 42% of the energy in the natural gas resource which is stored and not destroyed. A comparison is made between the well developed conventional SRM and the less developed TDM process including technological status, efficiency, carbon management and cost. The TDM process appears to have advantages over the well developed SRM process. It is much easier to sequester carbon as a stable solid than CO, as a reactive gas or low temperature liquid. It is also possible to reduce cost by marketing the carbon as a filler or construction material. The potential benefits ofthe TDM process justifies its further efficient development. The hydrogen can be used as a transportation fie1 or converted to methanol by reaction with CO, from fossil fuel fired power plant stack gases, thus allowing reuse of the carbon in conventional IC automobile engines or in advanced fuel cell vehicles.

The prospects for the electrochemical reduction of carbon dioxide to methanol were examined by investigating the intermediate reactions. The reduction of carbon dioxide was carried out in a neutral electrolyte at a mercury electrode. The high overvoltage observed for carbon dioxide reduction to the formate anion reflects a low value for the efficiency of electric energy utilization for this process. Formic acid can be reduced to methanol in a perchloric acid electrolyte (at a lead electrode) or in a buffered formic acid electrolyte (at a tin electrode). The faradaic efficiency for methanol formation is close to 100% at the tin electrode in a narrow potential region corresponding to a low current density. The potential dependence of formic acid reduction to methanol suggests that the adsorption of formic acid on the electrode, near the pzc, may be the rate‐controlling step in the over‐all reaction. The reduction of formaldehyde to methanol occurs with a faradaic efficiency exceeding 90% in a basic solution. The Tafel slope decreases when either the formaldehyde concentration is increased (at constant pH) or when thepH of the solution is increased (at constant concentration). The polyoxymethylene glycols present as impurities in formaldehyde solutions may influence the mechanism of the electrode process through interaction with formaldehyde molecules and/or other adsorbed species resulting in small changes of the Tafel slope.

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