Abstract:
This study deals with an economical, efficient, and sustainable catalytic process with excellent EcoScore and Efactor
values for the selective, two-step synthesis of 2,5-diformylfuran (with a yield higher than 90%) from
carbohydrates, especially disaccharide and polysaccharide. This catalytic process involves the abundant and low
cost carbohydrate as reactant and economical and sustainable catalysts, H-Beta and octahedral MnO2 molecular
sieve. In this two step approach, H-Beta is used in the first step for the conversion of carbohydrate to 5-hydroxymethylfurfural
(HMF). Brönsted acidity of H-Beta catalyzes the hydrolysis and dehydration reactions
whereas Lewis acidity catalyzes the isomerization to produce HMF. Thus, H-Beta is suitable for the conversion of
various carbohydrate molecules (starch, sucrose, glucose and fructose) to HMF. After the first step, H-Beta is
withdrawn and then the reaction mixture is subjected to oxidation catalyst, octahedral MnO2 molecular sieve, in
the presence of O2 atmosphere to achieve the high 2,5-diformylfuran (DFF) yield. Molecular oxygen (1 atmosphere,
O2 filled balloon) is used as an eco-friendly and economical oxidant. Furthermore, no over oxidation
product of DFF is observed. HMF and DFF are recovered from the reaction mixture by the extraction with methyl
isobutyl ketone (MIBK) using water and brine solutions. DFF yields of 97.1%, 95.3%, 93.4% and 91.5% are
obtained when the reactions are carried out using fructose, sucrose, glucose, and starch, respectively. Stepwise
addition of catalysts improves DFF yield (> 90%) from fructose, glucose, sucrose, and especially starch.
Moreover, the H-Beta and octahedral MnO2 molecular sieve are easily separable and recyclable.
