Lactose utilisation to furan carboxylates: a unique source for platform molecules

A highly efficient utilisation of lactose, a widely produced side-stream product to produce furancarboxylates in two steps, is presented. Firstly an enhanced nitric acid oxidation of lactose with Fe(NO3)3 to achieve a 75% yield of mucic acid was developed. Mucic acid was then quantitatively dehydrated to produce dibutyl-2,5-furandicarboxylate and butyl-2-furancarboxylate (66.6% and 33.1% respectively) using phosphotungstic acid catalyst in 1-butanol as a reaction solvent. The overall process presents and excellent carbon utilisation efficiency of 49.9 mol%. Conversion of lactose side-stream from the dairy industry into highly valuable furan carboxylates with excellent efficiency, through mucic acid as an intermediate, a potential source for PEF production (created with https://Biorender.com).