Combination of Brønsted and Lewis Polymeric Catalysts for Efficient Conversion of Cellulose into 5‐Hydroxymethylfurfural (HMF) in Ionic Liquids

Abstract

AbstractStable oil‐in‐water high internal phase emulsions (HIPEs) with an internal phase volume fraction of 85 % were stabilized using Tween 85. The prepared poly(HIPEs) were first investigated as adsorbents to treat water polluted with CrIII, and then the catalysts with Lewis acidic sites was synthesized. The catalysts with Brønsted acidic sites were obtained by ion‐exchanging. The as‐prepared HIPEs–CrIII (PEs–CrIII) and HIPEs–SO3H (PEs–SO3H) possess open‐cell structure, interconnecting pores, and strong acidity, they are utilized as highly efficient catalysts for the conversion of biomass to 5‐hydroxymethylfurfural (HMF). These results showed maximum production yields for cellulose, glucose, and fructose of 37.0 %, 58.0 %, and 80.8 %, respectively. PEs–CrIII and PEs–SO3H can be very easily recycled at least four times without significant loss of activity. Herein, a new method is presented to transform cellulose by using two catalysts in a one‐pot process for meeting the varying demands involved at different reaction stages.