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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]

Highlights: [•] Effect of pressure, temperature and feed ratio studied in detail. [•] CO2 utilization in combined coal gasification. [•] Thermoneutral points obtained in combined coal gasification. [•] Generation of syngas of required low syngas ratio. [•] Produced syngas has use in fuel cells. [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]

Abstract: The article explores the thermodynamics of an alternate hydrogen generation process – dry autothermal reforming and its comparison to autothermal reforming process of isooctane for use in gasoline fuel processors for SOFC. A thermodynamic analysis of isooctane as feed hydrocarbon for autothermal reforming and dry autothermal reforming processes for feed OCIR (oxygen to carbon in isooctane ratio) from 0.5 to 0.7 at 1bar pressure under analogous thermoneutral operating conditions was done using Gibbs free energy minimization algorithm in HSC Chemistry. The trends in thermoneutral points (TNP), important product gas compositions at TNPs and fuel processor energy requirements were compared and analyzed. Dry autothermal reforming was identified as a less energy consuming alternative to autothermal reforming as the syngas can be produced with lower energy requirements at thermoneutral temperatures, making it a promising candidate for use in gasoline fuel processors to power the solid oxide fuel cells. The dry autothermal reforming process for syngas production can also be used for different fuels. [Copyright &y& Elsevier]

Abstract: Dry autothermal reforming of ethanol can be used to produce a variety of value added products like hydrogen, syngas and also carbon (possible CNF). A thermodynamic analysis of dry autothermal reforming of ethanol has been carried out to locate the thermoneutral temperatures and product composition at those points at 1, 3, 6 and 9 bar reaction pressures. The variations of thermoneutral temperatures and individual product yields at those temperatures have been discussed to find the optimum operating parameters for desired product output from the process. The process operated at thermoneutral conditions can give useful products like hydrogen, syngas (of low ratio) and carbon (possibly CNFs) and also provide a way for CO2 sequestration using renewable ethanol fuel. A maximum of 2.58 moles of syngas of ratio 2.01 obtained at 1 bar, CER=1 and OER=0.5 along with 0.82 moles of carbon, 0.20 moles of CH4 and 0.89 moles of water for the thermoneutral temperature of 603.55°C was found to be the best operating thermoneutral point for value added product generation from this process. This study can be applied to a variety of fuels for producing value added products. [ABSTRACT FROM AUTHOR]

Abstract: Existing energy generation technologies emit CO2 gas and are posing a serious problem of global warming and climate change. The thermodynamic feasibility of a new process scheme combining chemical looping combustion (CLC) and combined reforming (CR) of propane (LPG) is studied in this paper. The study of CLC of propane with CaSO4 as oxygen carrier shows thermodynamic feasibility in temperature range (400–782.95°C) at 1bar pressure. The CO2 generated in the CLC can be used for combined reforming of propane in an autothermal way within the temperature range (400–1000°C) at 1bar pressure to generate syngas of ratio 3.0 (above 600°C) which is extremely desirable for petrochemical manufacture. The process scheme generates (a) huge thermal energy in CLC that can be used for various processes, (b) pure N2 and syngas rich streams can be used for petrochemical manufacture and (c) takes care of the expensive CO2 separation from flue gas stream and CO2 sequestration. The thermoneutral temperature (TNP) of 702.12°C yielding maximum syngas of 5.98mol per mole propane fed, of syngas ratio 1.73 with negligible methane and carbon formation was identified as the best condition for the CR reactor operation. The process can be used for different fuels and oxygen carriers. [Copyright &y& Elsevier]