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• #GAUSSIAN 09W DOWNLOAD CHEM 3D FREE#

Liquefied Petroleum Gas (LPG) Computational chemistry Hydrogen Equilibrium constant Thermodynamic dataĪpplication of computational chemistry methods to obtain thermodynamic data for hydrogen production from liquefied petroleum gas This last methodology is of special interest since it presents low computational cost, which is important when more complex molecular systems are considered. Gaussian-3 and Gaussian-4 theories are expected to be good thermodynamic data predictors and the known efficient prediction of vibrational frequencies by B3LYP is probably the source of the good agreement found in this study. Results showed that the hybrid functional B3LYP/6-31G++(d,p), G3 and G4 theories were the most appropriated methods to predict the properties of interest.

Mole fractions of the system components were also determined between 873.15 K, at 1 atm and a feed with a stoichiometric amount of water. Six computational approaches were used: Density Functional Theory (DFT) employing Becke's three parameter hybrid exchange functional, and the Lee-Yang-Parr correlation functional (B3LYP) using the 6-31G++(d,p) basis set and the composite methods CBS-QB3, Gaussian-1 (G1), Gaussian-2 (G2), Gaussian-3 (G3) and Gaussian-4 (G4). The reaction system of steam reforming of LPG was reported as a set of seven independent reactions involving the chemical species n-C4H10, C3H8, C2H6, C2H4, CH4, CO2, CO, H2O, H2 and solid carbon. The acquisition of those properties was made using computational chemistry methods and the results were compared with experimental data reported in the literature.

#GAUSSIAN 09W DOWNLOAD CHEM 3D FREE#

The objective of this study was to estimate thermodynamic data, such as standard enthalpy, entropy and Gibbs free energy changes of reaction and, consequently, chemical equilibrium constants, for a reaction system describing the hydrogen production from Liquefied Petroleum Gas (LPG).