Journal ArticleDOI
Effect of Mixed-Solvent Environments on the Selectivity of Acid-Catalyzed Dehydration Reactions
Alex K. Chew,Theodore W. Walker,Zhizhang Shen,Benginur Demir,Liam Witteman,Jack Euclide,George W. Huber,James A. Dumesic,Reid C. Van Lehn +8 more
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TLDR
In this paper, the authors report the kinetics and selectivity of 1,2-propanediol dehydration in pure water and in aqueous mixtures of the polar aprotic cosolvents γ-valerolactone, 1,4-dioxane, tetrahydrofuran, N-methyl-2-pyrrolidone, tetramethylene sulfoxide, and dimethyl sulfoxide at 433 K.Abstract:
The composition of the liquid phase can alter the rates of individual reaction steps and thus alter the selectivity of acid-catalyzed reactions, but these solvent effects are difficult to anticipate for design purposes. Herein, we report the kinetics and selectivity of Bronsted acid-catalyzed 1,2-propanediol dehydration in pure water and in aqueous mixtures of the polar aprotic cosolvents γ-valerolactone, 1,4-dioxane, tetrahydrofuran, N-methyl-2-pyrrolidone, tetramethylene sulfoxide, and dimethyl sulfoxide at 433 K. We find that the major product of 1,2-propanediol dehydration is propanal in most mixed-solvent environments with selectivities between 1 and 68 mol %. In contrast, 1,2-propanediol dehydration in aqueous mixtures of dimethyl sulfoxide affords acetone as the major product with up to 48% selectivity with minimal propanal formation. We use classical molecular dynamics simulations to probe these solvent effects by computing the difference between the solvation free energies of 1,2-propanediol and ...read more
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Computational Methods in Heterogeneous Catalysis
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Solvent Effects in Acid-Catalyzed Biomass Conversion Reactions
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Structure and solvation of confined water and water-ethanol clusters within microporous Brønsted acids and their effects on ethanol dehydration catalysis.
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Advances in Understanding the Selective Hydrogenolysis of Biomass Derivatives
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Influence of solvent structure and hydrogen bonding on catalysis at solid-liquid interfaces.
TL;DR: In this paper, the authors show that solvent molecules can modify the free energies of liquid phase and surface species via solvation, participating directly as a reactant or co-catalyst, or competitively binding to active sites.
References
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