Direct 2,3-Butanediol Conversion to Butene-Rich C3+ Olefins over Copper-Modified 2D Pillared MFI: Consequence of Reduced Diffusion Length

• Published in: ACS sustainable chemistry & engineering Vol. 10; no. 4; pp. 1664 - 1674
• Main Authors: Adhikari, Shiba, Zhang, Junyan, Unocic, Kinga, Wegener, Evan C, Kunal, Pranaw, Deka, Dhruba J, Toops, Todd, Sinha Majumdar, Sreshtha, Krause, Theodore R, Liu, Dongxia, Li, Zhenglong
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 31.01.2022; American Chemical Society (ACS)
• Subjects: 2,3-butanediol; 2D zeolite; butane; catalysts; chemical reactions; coke; decarbonization; diffusion free; hydrocarbons; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; selectivity; sustainable aviation fuels; Diffusion free; Butene; 2,3-Butanediol; Decarbonization; 2D zeolite; Sustainable aviation fuels
• ISSN: 2168-0485; 2168-0485
• DOI: 10.1021/acssuschemeng.1c07670

2,3-Butanediol (2,3-BDO), a critical C4 platform chemical derived from biomass, syngas, or CO2, can be converted to C3+ olefins, serving as important renewable feedstocks for producing sustainable aviation fuels to decarbonize the hard-to-electrify air transportation sector. Herein, we report a bifunctional Cu-modified diffusion-free 2D pillared MFI catalyst (Cu/PMFI) which can selectively catalyze 2,3-BDO conversion to butene-rich C3+ olefins (95% selectivity at 97% conversion, 523 K). 2,3-BDO conversion to butenes over Cu/PMFI primarily occurs via methyl ethyl ketone intermediate while 2-methyl propanal is also observed as another minor dehydration product that leads to butene formation. In comparison with a control mesoporous Cu/ZSM-5 sample prepared by the postsynthetic approach, Cu/PMFI shows favorable C3+ olefin selectivity (95% over Cu/PMFI vs 80% over Cu/ZSM-5 at ∼5.1 h TOS). The coke formation over Cu/PMFI is dramatically suppressed by >50% in contrast to Cu/ZSM-5 in 90 h 2,3-BDO conversion due to the reduced diffusion length. Cu/PMFI also favors butene formation and minimizes nonbutene C3+ olefins by inhibiting the downstream oligomerization and cracking reactions. This study highlights the usefulness of the diffusion-free 2D PMFI materials in catalytic conversion of biomass-derived platform molecules and the significance of diffusion impact on catalyst coke formation and product distributions.