Rational screening of transition metal single-atom-doped ZSM-5 zeolite catalyst for naphtha cracking from microkinetic analysis

Metal doped ZSM-5 catalyst has attracted much attention due to its unique catalytic activity for C-H bond activation. In this work, based on density functional theory (DFT) calculations and microkinetic analysis, we prospectively explored the catalytic activity of 12 kinds of transition metals (M = Fe, Co, Ni, Cu, Mo, Ru, Rh, Pd, Ag, W, Pt, Au) single-atom-doped ZSM-5 zeolite catalysts in the catalytic cracking of naphtha. The results show that there is a strong electronic interaction between metal atom and ZSM-5 skeleton. This induced stable structure could improve the adsorption ability of hydrocarbon, thus promoting the activation of C-H bond and the cracking of carbenium ion. Moreover, C and H binding energy were identified as descriptors in describing catalytic activity via good scaling relations. The turnover frequency volcano diagram shows that the Ag and Cu doped ZSM-5 zeolite catalyst is close to the best choice. In addition, Pd and Mo are potential metal choices with good selectivity through selectivity analysis. This work has important guiding significance for understanding the fluid catalytic cracking (FCC) mechanism and designing high-efficiency cracking catalysts.

Automated summary

Metal doped ZSM-5 catalysts have been extensively studied for their unique catalytic activity in C-H bond activation. In this work, we used density functional theory calculations and microkinetic analysis to explore the catalytic activity of 12 transition metal single-atom-doped ZSM-5 zeolite catalysts in the catalytic cracking of naphtha. Our results show a strong electronic interaction between the metal atom and ZSM-5 skeleton, leading to a stable structure that enhances hydrocarbon adsorption and promotes C-H bond activation and carbenium ion cracking. Carbon and hydrogen binding energy were identified as descriptors for catalytic activity.