The Conversion of 5-chloromethylfurfural Into 5-methoxymethylfurfural via Nucleophilic Substitution: Kinetic Modelling

Abstract

The nucleophilic substitution of chlorine into the 5-chloromethylfurfural (CMF) by methanol is a high potential route for the production of 5-methoxymethylfurfural (MMF), allowing the production of 2,5-furandicarboxylic acid, an important intermediate for polyester synthesis with larger yield and selectivity than 5-hydroxymethylfurfural. However, HCl, produced during the nucleophilic substitution, leads to the formation of by-products like humins or methyl levulinate, and it is faced by adding bases to the reaction with the side effect of producing large amounts of waste as salts. On the contrary, optimizing the MMF yields in the absence of any base could allow the recycling of the produced HCl into the CMF production process, with benefits for the whole route. To optimize the reaction, CMF was reacted with methanol at low concentration, using a multi-reactor in batch mode, to maximize the MMF yield at 10, 20, 40, and 50 °C. Finally, a lumped kinetic model was employed to analyse the reaction further. The yield of MMF and its corresponding acetal increase with a reaction time and temperature of up to 60 % in 1.5 h.