Thermodynamic and kinetic analysis of the thermal partial oxidation of n-heptane for the production of hydrogen rich gas mixtures

In this work, thermodynamic and kinetic analysis of the thermal partial oxidation of n-heptane (as diesel surrogate) is performed. Equilibrium and kinetic analyses are performed with the CHEMKIN simulation package. In this kinetic study, two different reactor configurations are considered: The free flame and the batch reactor. The effect of several parameters including the mixture inlet temperature, the air fuel ratio (λ), the pressure and the residence time are investigated. The results show that a possible operating condition for the thermal partial oxidation (TPOX) can be achieved at λ = 0.4 to λ = 0.45 with an air preheating temperature of 1000 K. At these conditions, the thermodynamic reforming efficiency is found to be as high as 77 and 70 percent for λ = 0.4 and λ = 0.45, respectively. The kinetic analysis shows that TPOX process of n-heptane consists of three different regimes: oxidation zone, WGS zone and reforming zone. Moreover, the transport properties of the reactive species affect the TPOX process in the oxidation region, while the process in the water gas shift reaction regime (WGS) and reforming reaction regime is controlled by the reaction kinetics.