From each simulation, the: moles of CH 4 converted, Equation ( ), moles of O 2 converted, CO and H 2 (synthesis gas) yield and selectivity, CO 2 and H 2 O (full oxidation) yield and selectivity, and temperature at the end of the PFR were obtained. The sum of the selectivities of H 2 Equation ( ), and CO Equation ( ) was used to describe synthesis gas selectivity Equation ( ), seen below: