Answer Happy

A 1999 paper by Ahmed & colleagues at ANL “Catalytic Partial Oxidation Reforming of Hydrocarbon Fuels” investigated the catalytic conversion of several liquid fuels into a reformate gas that can be used by PEM fuel cells. This reaction can be achieved with or without a catalyst, though the non-catalytic processes require reaction temperatures up to 1000 C, which significantly reduces the efficiency of the conversion process. Using a catalyst allows the reaction to proceed at lower temperatures, and a closer approach to equilibrium conditions.The most convenient liquid fuel is gasoline, as there is already strong distribution infrastructure in place. Ahmed reports that they can reform liquid iso-octane (still C8H18) at 630 C into a product gas with a composition of 62.5% H2, 16.7% CO, 20.8% CO2 on a dry, nitrogen-free basis. The enthalpy of formation for liquid iso-octane is -249,910 kJ/mol and its specific entropy (3rd law reference state) is 360.79 kJ/kmol-K. The overall reaction is:C8H18 + x (O2+3.76N2) + yH2O → aCO2 + bH2 + cN2 + dCO + eH2OThe water flow in this experiment is adjusted to provide a water to carbon atom ratio of 1.1. Assume that water is provided as a liquid at 25 C and the reaction is conducted at atmospheric pressure. The overall reaction is endothermic, requiring heat input. In your analysis, assume that heat is provided to the catalyst bed at 630C and that products exit the reactor at 630C. Heat can be obtained by cooling the products from 630 to 25 C. Assume that all of this energy can be used to offset the energy required for the reaction. Base all of your availability calculations to the reference environment given below. Reference environment: 298.15 K, 101.3 kPaSubstance: mole fraction:N2 0.7567O2 0.2035H2O (g) 0.0303CO2 0.0003a. Calculate the total availability of the reactant and product gasesb. Calculate the second law efficiency for this process. c. What are the implications of using gasoline as a hydrogen source based on your result?
A 1999 paper by Ahmed & colleagues at ANL “Catalytic Partial Oxidation Reforming of Hydrocarbon
Fuels” investigated the catalytic conversion of several liquid fuels into a reformate gas that can be used by
PEM fuel cells. This reaction can be achieved with or without a catalyst, though the non-catalytic processes
require reaction temperatures up to 1000 C, which significantly reduces the efficiency of the conversion
process. Using a catalyst allows the reaction to proceed at lower temperatures, and a closer approach to
equilibrium conditions.
The most convenient liquid fuel is gasoline, as there is already strong distribution infrastructure in place.
Ahmed reports that they can reform liquid iso-octane (still C8H18) at 630 C into a product gas with a
composition of 62.5% H2, 16.7% CO, 20.8% CO2 on a dry, nitrogen-free basis. The enthalpy of formation
for liquid iso-octane is -249,910 kJ/mol and its specific entropy (3rd law reference state) is 360.79 kJ/kmol-
K. The overall reaction is:
C8H18 + x (O2+3.76N2) + yH2O → aCO2 + bH2 + cN2 + dCO + eH2O
The water flow in this experiment is adjusted to provide a water to carbon atom ratio of 1.1. Assume that
water is provided as a liquid at 25 C and the reaction is conducted at atmospheric pressure. The overall
reaction is endothermic, requiring heat input. In your analysis, assume that heat is provided to the catalyst
bed at 630C and that products exit the reactor at 630C. Heat can be obtained by cooling the products from
630 to 25 C. Assume that all of this energy can be used to offset the energy required for the reaction. Base
all of your availability calculations to the reference environment given below.
Reference environment: 298.15 K, 101.3 kPa
Substance: mole fraction:
N2 0.7567
O2 0.2035
H2O (g) 0.0303
CO2 0.0003
a. Calculate the total availability of the reactant and product gases
b. Calculate the second law efficiency for this process.
c. What are the implications of using gasoline as a hydrogen source based on your result?
A 1999 paper by Ahmed & colleagues at ANL "Catalytic Partial Oxidation Reforming of Hydrocarbon Fuels” investigated the catalytic conversion of several liquid fuels into a reformate gas that can be used by PEM fuel cells. This reaction can be achieved with or without a catalyst, though the non-catalytic processes require reaction temperatures up to 1000 C, which significantly reduces the efficiency of the conversion process. Using a catalyst allows the reaction to proceed at lower temperatures, and a closer approach to equilibrium conditions. The most convenient liquid fuel is gasoline, as there is already strong distribution infrastructure in place. Ahmed reports that they can reform liquid iso-octane (still CSH) at 630 C into a product gas with a composition of 62.5% H2, 16.7% CO, 20.8% CO2 on a dry, nitrogen-free basis. The enthalpy of formation for liquid iso-octane is -249.910 kJ/mol and its specific entropy (3rd law reference state) is 360.79 kJ/kmol- K. The overall reaction is: CsHix + x (O2+3.76N2) + yH2O → aCO2 + bH2 + CN2 + dCO + eH20 The water flow in this experiment is adjusted to provide a water to carbon atom ratio of 1.1. Assume that water is provided as a liquid at 25 C and the reaction is conducted at atmospheric pressure. The overall reaction is endothermic, requiring heat input. In your analysis, assume that heat is provided to the catalyst bed at 630C and that products exit the reactor at 630C. Heat can be obtained by cooling the products from 630 to 25 C. Assume that all of this energy can be used to offset the energy required for the reaction. Base all of your availability calculations to the reference environment given below. Reference environment: 298.15 K, 101.3 kPa Substance: mole fraction: N2 0.7567 02 0.2035 H:0 (g) 0.0303 CO2 0.0003 a. (10 pts) Calculate the total availability of the reactant and product gases b. (10 pts) Calculate the second law efficiency for this process. c. (5 pts) What are the implications of using gasoline as a hydrogen source based on your result?