A H2-free heterogeneous route to glycerol-based acrylics via Re-based deoxydehydration

Abstract

A novel catalytic route from bio-based glyceric acid to acrylic acid and its esters, key polymer precursors, has been developed. This sustainable process involves rhenium-catalyzed deoxydehydration (DODH) in an alcoholic medium, avoiding gaseous hydrogen or other hazardous reagents. Using a supported Re/C catalyst and methanol as solvent, a combined yield of acrylic acid and methyl acrylate of up to 65% was obtained at 150 °C after 72 h under an inert N₂ atmosphere. Moreover, conducting the same reaction under 5 bar of H₂ at an increased temperature of 180 °C boosts the DODH rate constant from 0.21 ± 0.03 to 4.08 ± 0.22 h⁻¹ g_cat⁻¹, thus yielding more than 90% of DODH products in just 10 h. This sustainable process is easily transferable to other alcohols that yield alkyl acrylates, further expanding the applicability of the presented invention to other monomers and products.