C2H2 selective hydrogenation over transition metal carbide (MxCy): Probing into the influences of crystal facet, M type and M: C ratio on C2H4 activity, selectivity and catalyst stability. (15th March 2023)

• Record Type: Journal Article
• Authors: Wang, Li; Wang, Baojun; Fan, Maohong; Ling, Lixia; Zhang, Riguang
• Is Part Of: Fuel. Volume 336(2023)
• Publication Date: 2023-03-15
• Subjects: Metal carbide -- Structure -- Composition -- Catalytic performance -- C2H2 selective hydrogenation; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2022.127131
• Languages: English
• ISSNs: 0016-2361

Abstract

Graphical abstract: Highlights: Mx Cy surface structure and composition obviously affect catalytic performance of C2 H2 selective hydrogenation. Catalytic performance of Mx Cy catalysts strongly depends on the ensemble and/or ligand effects. α-MoC(1 0 1) is screened out to exhibit better catalytic performance than the industrial PdAg/Al2 O3 catalyst. C2 H4 activity on α-MoC(1 0 1) behaves as Pt-like high activity due to Pt-like electronic properties. Abstract: Aiming at probing into the structure and composition sensitivity of transition metal carbides (Mx Cy ) to catalytic performance of C2 H2 selective hydrogenation, twenty-three kinds of Mx Cy (M = Ti, Zr, Hf, Mo, W and Co) catalysts with different M types, crystal facets and M: C ratios are investigated using DFT calculations and microkinetic modeling. The results show that C2 H4 activity and selectivity depend on surface composition and structure due to the ensemble and/or ligand effects. Charge transfer number from M to C atoms and d -band center can be used as the descriptors to efficiently evaluate C2 H4 selectivity and activity over Mx Cy catalysts, respectively. α-MoC(1 0 1) is screened out to exhibit Pt-like electronic properties with better C2 H4 activity, selectivity, and catalyst stability to resist green oil formation compared to Pt and other Mx Cy catalysts when the temperature is ≤425 K and H2 : C2 H2 ratio is ≥1: 1, which is superior to the industrial PdAg/Al2 O3 catalyst.