Continuous Flow Catalyst-Free Mechanochemical Conversion of Isoeugenol and Vanillyl Alcohol for Vanillin Production: From Lab Experiments to Scaled-Up Premises

Abstract

The potential of combining continuous flow and mechanochemistry for biomass valorization was explored in this work. Vanillin production employing isoeugenol and vanillyl alcohol as sustainable biomass-derived feedstocks was chosen due to the relevance of this flavoring molecule and the current need to find alternative starting materials to industrially used petro-based compounds. The combination of continuous flow and mechanochemistry led to outstanding results in terms of conversion, selectivity, and yield of vanillin by performing the reaction in the absence of catalysts from the lab to scale-up results (a 0.5−1 L DYNO-MILL Multi Lab reactor). The transformation of vanillyl alcohol toward vanillin was additionally performed in a DYNO-MILL Research Lab, a laboratory scale flow mechanochemical reactor (Willy A. Bachofen AG, Switzerland), observing optimum values of conversion, selectivity, and yield of the product of interest.

Catalyst-free valorization of biomass resources to value-added products

“…141 Combining continuous flow and mechanochemistry, Martín-Perales et al successfully synthesized vanillin in a scale-up version from the oxidation of bio-based isoeugenol and vanillyl alcohol. 142 A good yield of vanillin was achieved in the presence of hydrogen peroxide as an oxidant in two novel mechanochemical reactors. Both basic reaction parameters and types of instruments can affect the reaction efficiency.…”