Reactive molecular dynamics study on catalytic pyrolysis and steam reforming of hydrocarbon fuel

The strong endothermic capability of catalytic steam reforming highlights its potential for improving the heat sink of hydrocarbon fuels. To explore the complex interaction between catalytic pyrolysis and steam reforming reactions, as well as their contributions to the heat sink of fuels, the reactive force-field molecular dynamics (ReaxFF-MD) simulation is employed in this work to investigate the palladium-catalyzed pyrolysis and steam reforming of n-dodecane (n-C12H26). The results show that pyrolysis reaction supplies C1 and C2 components, and then participates in the steam reforming generating more than 90% of aldehyde groups. Meanwhile, compared to catalytic pyrolysis reaction, the catalytic steam reforming containing 25 n-C12H26 and 300 H2O reduces 40.54% of carbon atoms deposited inside the palladium lattice, and improves the heat sink from 254.18 kcal/mol to 386.03 kcal/mol. Furthermore, our simulated results quantitatively describe the detailed contributions of catalytic pyrolysis and steam reforming to the simulation process. With more H2O added, the proportion of steam reforming gradually increases, which reaches 35.08% in the system containing 25 n-dodecane and 300 H2O. Moreover, the contribution of H atoms in the formation of H2 also indicates the variation in the proportion of steam reforming.