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Thermodynamic equilibrium analysis has been adopted for oxidative steam reforming of butanol-ethanol mixture (B-E) as renewable source obtained from Acetone:Butanol:Ethanol (ABE) fermentation to produce H 2 by using Gibbs free energy minimization method. The effects of pressure (1–10 atm), temperature (573–1473 K), steam/fuel molar feed ratio ( f O1 = 9 and 12), O 2 /fuel molar feed ratio ( f O2 = 0–3), and B-E mixture compositions (50–90%B) on equilibrium compositions of H 2 , CO, CO 2 , CH 4 , and carbon are performed. The maximum H 2 yield (65.456% for f O2 = 0 and 58% for f O2 = 0.75) has been achieved at f O1 = 9, 90% B mixture, 1 atm, and 973 K. The yields of CO, CO 2 , and CH 4 with respect to maximum H 2 are 53.390%, 44.384%, and 2.225% for f O2 = 0, and 45.677%, 53.269%, and 1.053% for f O2 = 0.75, respectively. Energy required per mol of H 2 , thermal and exergy efficiencies for the process are also evaluated to utilize the potential of B–E mixture for H 2 production. [ABSTRACT FROM AUTHOR]

Abstract: The thermodynamic analysis of steam reforming of methanol without and with fractional removal of H2 and CO2 in adsorption, membrane and adsorption-membrane hybrid reactor systems to produce fuel cell grade H2 with minimal carbon formation is investigated. The results indicate that the removal of undesired CO2 by CO2 adsorbent is most effective process for the production of high purity H2 than H2 removal by membrane. However, the membrane is effective only above 30% H2 removal. It is possible to obtain H2 yield of 2.6 with negligibly small amount of CO and carbon formation at T = 405 K, P = 1 atm, 80% removal of CO2 and 100% methanol conversion. Identical results are achieved even at lower temperature of 345 K in adsorption-membrane hybrid reactor system at 80% removal of H2 and CO2. Thus high grade H2 can be produced by single step process and further processing to reduce CO by PROX reactor is not necessary. [Copyright &y& Elsevier]

Abstract: A one-dimensional non-isothermal model for oxygen permeable membrane reactor has been developed to simulate the partial oxidation of methane to produce hydrogen. The performance of two fixed bed reactors (FBRs) viz. one with pure O2 in feed (FBR1), other with air in feed (FBR2), and a membrane reactor (MR) having air in non-reaction side have been studied at various feed conditions and inlet temperatures in order to investigate the effect of these parameters on conversion of methane and yield of hydrogen. The fixed bed reactor with pure O2 in feed has been found to provide better performance as compared to fixed bed reactor with air and membrane reactor. [Copyright &y& Elsevier]

The paper aims to investigate the steam reforming of biogas in an industrial-scale reformer for hydrogen production. A non-isothermal one dimensional reactor model has been constituted by using mass, momentum and energy balances. The model equations have been solved using MATLAB software. The developed model has been validated with the available modeling studies on industrial steam reforming of methane as well as with the those on lab-scale steam reforming of biogas. It demonstrates excellent agreement with them. Effect of change in biogas compositions on the performance of industrial steam reformer has been investigated in terms of methane conversion, yields of hydrogen and carbon monoxide, product gas compositions, reactor temperature and total pressure. For this, compositions of biogas (CH 4 /CO 2 = 40/60 to 80/20), S/C ratio, reformer feed temperature and heat flux have been varied. Preferable feed conditions to the reformer are total molar feed rate of 21 kmol/h, steam to methane ratio of 4.0, temperature of 973 K and pressure of 25 bar. Under these conditions, industrial reformer fed with biogas, provides methane conversion (93.08–85.65%) and hydrogen yield (1.02–2.28), that are close to thermodynamic equilibrium condition. • A model for an industrial reformer for steam reforming of biogas (SRB) developed. • Preferable process feed conditions are P = 25 bar, T = 973 K, S/C = 4 and heat flux = 65 kW/m2. • An existing industrial reformer for steam reforming of methane can be used for SRB. • Performance of industrial reformer is close to that achieved at equilibrium. • The study provides the guidelines for industrial steam reforming of biogas (SRB). [ABSTRACT FROM AUTHOR]