Solid Acid Catalysts Based on Niobium and Zirconium Oxides for Hydrolysis-Dehydration of Cellulose Into Glucose and 5-Hydroxymethylfurfural. Impact of Preparation Technique on Catalytic Properties

Abstract

The impact of the preparation techniques of niobium oxide and two-component systems based on niobium and zirconium oxides on the catalytic properties was studied in the one-pot hydrolysisdehydration of cellulose into glucose and 5-hydroxymethylfurfural. Cellulose transformation was performed in an autoclave at 180 °С under argon atmosphere. The most promising methods for the preparation of solid catalysts were found to be microwave heating and mechanical activation. Glucose and 5-hydroxymethylfurfural can be produced with total yield equal to 20-21 % in the presence of catalysts prepared using these techniques

Hydrolysis–Dehydration of Cellulose: Efficiency of NbZr Catalysts under Batch and Flow Conditions

“…Materials based on niobium and zirconium oxides are of considerable interest in the processing of cellulose into 5-HMF due to the existing acid-base sites [19] and their high stability in hot water [23][24][25][26]. We previously investigated [27,28] one-pot hydrolysisdehydration of mechanically activated cellulose in pure hot water to produce glucose and 5-hydroxymethylfurfural in the presence of amorphous niobium oxide supported on a zirconium dioxide (NbO x /ZrO 2 ). It was found that activity of NbO x /ZrO 2 systems depended on the Nb 2 O 5 content and decreased as follows: 2.8%Nb/ZrO 2 ~1.1%Nb/ZrO 2 ZrO 2 > 0.5%Nb/ZrO 2 .…”