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Summary: Autothermal reforming of methane is one of the most widely reported techniques for syngas production. This thermodynamic analysis discusses two aspects of autothermal reforming: first, to obtain hydrogen to nitrogen in the ratio 3:1, which is the most suitable feed ratio for ammonia production in the Haber–Bosch process, and then to find out the thermoneutral point of the process. Throughout the study, all simulations are carried out at 1 bar pressure and within the temperature range 500–1000°C. Conditions with more than 99% methane conversion and 0.1% coke deposition are considered. Other parameters taken into account for optimization are OMR (oxygen to methane ratio) in range 0.4–0.6, SMR (steam to methane ratio) in range 1.5–3.5 and oxygen enrichment in air from 25% to 40%. This study briefly discusses the water gas shift (WGS) reaction for CO removal and its conversion to H2. The best thermoneutral point for the reformer was found to be at OMR = 0.59845, SMR = 2.105, with an oxygen enrichment level of 39.4%. [ABSTRACT FROM AUTHOR]

ABSTRACT The reaction enthalpy (ΔH) of reforming processes like steam and dry (CO2) reforming is of great importance for scale-up and process development. Generally, the reforming processes are considered endothermic in nature. However, a detailed study of the reaction enthalpy of reforming process, taking the example of dry reforming of ethanol considered in this study, reveals the existence of exothermic reaction enthalpy at low temperatures. A study of reaction enthalpy of ethanol dry reforming within pressure (1-10 bar), temperature range (300-900 °C), and CO2 to carbon in ethanol ratio (CCER 1-5) was initiated to determine the existence of thermoneutral temperatures for the overall reaction. The variation of thermoneutral conditions and product yields at the thermoneutral temperatures was studied. The utilization potential of the products generated at thermoneutral conditions was also evaluated. The low-pressure thermoneutral operation favored higher hydrogen production, lower methane and water formation, whereas the high-pressure thermoneutral operation favored product gas of lower syngas ratio with higher CO2 conversion (utilization) in the process. The study can be extended to steam and dry reforming of other fuels to generate valuable products at thermoneutral conditions avoiding use of air in the process and subsequent N2 dilution of the product gas. © 2013 Curtin University of Technology and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The prospect of ethanol dry reforming process to utilize CO2 for conversion to hydrogen, syngas, and carbon nanofilaments using abundantly available biofuel--ethanol, and widely available environmental pollutant CO2 is very enthusiastic. A thermodynamic analysis of ethanol CO2 reforming process is done using Gibbs free energy minimization methodology within the temperature range 300-900°C, 1-10 bar pressure, and CO2 to carbon (in ethanol) ratio (CCER) 1-5. The effect of individual as well as combined effect of process parameters such as temperature, pressure, and CCER was determined on the product distribution. Optimum process conditions for maximising desired products and minimizing undesired products for applications such as gas to liquids (GTL) via fischer tropsch synthesis, syngas generation for Solid oxide fuel cells, and carbon nanofilament manufacture were found in this study. [ABSTRACT FROM AUTHOR]

SUMMARY Chemical looping reforming (CLR) is a novel technology that can be used for reforming of cheaply available abundant biofuel like ethanol for the production of hydrogen/syngas for fuel cells. A systematic thermodynamic study for the CLR process using selected oxygen carriers was done to analyze the products and energy requirements of the CLR process in the temperature range of 500-1200 °C at 1 bar pressure for ethanol. The results showed favorable conditions for syngas manufacture from this process. Fe2O3 was found to be the best performing oxygen carrier followed by calcium and sodium sulfates, while Mn oxides were the least preferred oxygen carriers for CLR of ethanol process. The optimum process temperature was found to be 1000 °C. The actual CLR-ethanol process shows exothermicity against the theoretical endothermic partial oxidation of ethanol. The results obtained in this theoretical study can pave the way for experimental programs for syngas generation for SOFC-type fuel cells. Similar studies can be undertaken for other fuels for fuel processor development by CLR process. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: The fuel cell economy is yet to start research programs in hydrogen generation with CO2 utilization for hydrocarbon reforming processes used in fuel processor applications. A simple thermodynamic study using solvay clusters was done to investigate the feasibility of using the carbon species produced in the steam methane reforming process to produce value added chemicals. The results of this study are highly encouraging to start process development of closed systems of hydrogen generation with CO2 conversion to acetic acid/acrylic acid making easier the commercialization of fuel cells and hydrogen energy. Such studies can be specifically carried out for different fuel processor systems. [Copyright &y& Elsevier]