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Acetone–butanol–ethanol–water mixture is obtained by fermentation of biomass namely, corncob, wheat straw, sugarbeets, sugarcane, etc. For using the individual components, one alternative is to separate the mixture by distillation, which is costly and energy intensive operation. This paper proposes its other use in available conditions to produce hydrogen fuel by oxidative steam reforming process. For the proposed process, thermodynamic equilibrium modeling has been performed by using non-stoichiometric approach of Gibbs free energy minimization. The compositions of acetone, butanol and ethanol in mixture are 0.33:0.52:0.15 on molar basis. The influence of pressure (1–10 atm), temperature (573–1473 K), steam to ABE mixture molar feed ratio (FABE = 5.5–8.5), and oxygen to ABE mixture molar feed ratio (FOABE = 0.25–1) have been tested by simulations on the yield of products (at equilibrium) namely, H2, CH4, CO2, CO, and carbon as solid. The optimum conditions for maximum production of desired H2, minimization of undesired CH4, and elimination of carbon (solid) formation are T = 973 K, P = 1 atm, FABE = 8.5, and FOABE = 0.25. Under same operating conditions, the maximum generation of H2 is 7.51 on molar basis with negligible carbon formation. The total energy requirement for the process (295.73 kJ/mol), the energy required/mol of hydrogen (39.37 kJ), and thermal efficiency (68.09%) of the reformer have been obtained at same operating conditions. The exergy analysis has also been investigated to measure the work potential of the energy implied in the reforming process. [ABSTRACT FROM AUTHOR]

A thermodynamic equilibrium analysis on steam reforming process to utilize acetone-butanol-ethanol-water mixture obtained from biomass fermentation as biorenewable fuel has been performed to produce clean energy carrier H 2 via non-stoichiometric approach namely Gibbs free energy minimization method. The effect of process variables such as temperature (573–1473 K), pressure (1–10 atm), and steam/fuel molar feed ratio ( F ABE  = 5.5–12) have been investigated on equilibrium compositions of products, H 2 , CO, CO 2 , CH 4 and solid carbon. The best suitable conditions for maximization of desired product H 2 , suppression of CH 4 , and inhibition of solid carbon are 973 K, 1 atm, steam/fuel molar feed ratio = 12. Under these conditions, the maximum molar production of hydrogen is 8.35 with negligible formation of carbon and methane. Furthermore, the energy requirement per mol of H 2 (48.96 kJ), thermal efficiency (69.13%), exergy efficiency (55.09%), exergy destruction (85.36 kJ/mol), and generated entropy (0.29 kJ/mol.K) have been achieved at same operating conditions. [ABSTRACT FROM AUTHOR]