Revealing the influence of temperature on benzene oxidation by palladium oxide via ReaxFF molecular dynamics simulations

Abstract

For catalytic reactions, temperature has a great influence on reaction rate and reaction mechanism. The oxidation processes of soot precursors (C6H6) at different temperatures are simulated using reactive force field molecular dynamics to investigate the effect of temperature on the oxidation process. The reaction products at different temperatures and the effect of temperature are discussed. The results show that the intermediate species C3 and C4 are more and existed longer at 1400 K than at 2000 K, while hardly existed at 2000 K, indicating that as the temperature increases, the oxidation reaction takes place more completely and the products formed are more stable. The effect of temperature on the oxidation mechanism is then explored; the results show that the main reaction pathway at 1400 K is basically the same as that at 2000 K, while the final product contains less hydrogen and more oxygen atoms at 2000 K. The C6 components with two, three, and four oxygen atoms are found easier to be decomposed at both 1400 and 2000 K. It shows that temperature mainly affects the catalytic reaction process by affecting the hydrogen and oxygen content of the decomposed C6 component. This may be helpful to understand the effect of temperature on the C6H6 oxidation from the perspective of basic research.