Potassium-Modified ZSM-5 Catalysts for Methyl Acrylate Formation from Methyl Lactate: The Impact of the Intrinsic Properties on Their Stability and Selectivity

Methyl lactate (ML) conversion to methyl acrylate is studied in the gaseous phase over ZSM-5 zeolite catalysts. High acrylate selectivity and catalyst service time were achieved using the K-ZSM-5 catalyst with low content of Brønsted acid sites (below 1 μmol g–1) and an overall K-to-Al atom ratio of unity. Feeding of ML in methanol containing 5 to 25 vol % of water improves catalyst stability. As such, up to 80% acrylate yield at complete ML conversion, along with minor deactivation after days-on-stream and fully recoverable catalysis, is presented.