Affiliation:
1. Department of Chemical and Biomolecular Engineering University of Illinois Urbana-Champaign Urbana IL 61801 USA
2. C1 Gas & Carbon Convergent Research Center Korea Research Institute of Chemical Technology Daejeon 34114 Korea
3. Core R&D, The Dow Chemical Company Midland MI 48674 USA
4. Dow Industrial Solutions The Dow Chemical Company Freeport TX 77566 USA
Abstract
AbstractEsters reduce to form ethers and alcohols on contact with metal nanoparticles supported on Brønsted acidic faujasite (M‐FAU) that cleave C−O bonds by hydrogenation and hydrogenolysis pathways. Rates and selectivities for each pathway depend on the metal identity (M=Co, Ni, Cu, Ru, Rh, Pd, and Pt). Pt‐FAU gives propyl acetate consumption rates up to 100 times greater than other M‐FAU catalysts and provides an ethyl propyl ether selectivity of 34 %. Measured formation rates, kinetic isotope effects, and site titrations suggest that ester reduction involves a bifunctional mechanism that implicates the stepwise addition of H* atoms to the carbonyl to form hemiacetals on the metal sites, followed by hemiacetal diffusion to a nearby Brønsted acid site to dehydrate to ethers or decompose to alcohol and aldehyde. The rates of reduction of propyl acetate appear to be determined by the H* addition to the carbonyl and by the C−O cleavage of hemiacetal.