Thermodynamic Equilibrium Analysis of Glucose Conversion to Hydrocarbons.

Abstract

Deoxygenation, or removal of oxygen from oxygenates, is an important process in hydrocarbon fuels production from biorenewable substrates. A thermodynamic equilibrium analysis on such reactions gives valuable insights on the theoretical limits of desired products when a substrate is reacted under a given set of conditions. Here we report the equilibrium composition of glucose-to-hydrocarbon system by minimizing the total Gibbs energy of the system. The system was treated as a mixture of 11 components which had C6H6, C7H8, C8H10 (ethyl benzene), C8H10 (xylenes), C6H5 OH , CH4, H2O, C, CO2, CO, H2. Equilibrium compositions of each species were analyzed for temperatures ranging from 300 -1500 K and pressure at 0- 15 atm gauge. It was observed that at high temperature CO and H2 dominates the equilibrium mixture with mole fraction of 0.597 and 0.587 respectively. At low temperatures equilibrium mixture is dominated by CH4, CO2, H2O and atomistic carbon. The aromatic hydrocarbon composition observed at thermodynamic equilibrium is extremely small.