Ruthenium trichloride catalyzed conversion of cellulose into 5-hydroxymethylfurfural in biphasic system

The production of 5-hydroxymethylfurfural (5-HMF) from cellulose catalyzed by a series of transition metal chlorides (i.e. FeCl 3 , RuCl 3 , VCl 3 , TiCl 3 , MoCl 3 and CrCl 3 ) was studied in biphasic system. RuCl 3 was the most efficient catalyst among these transition metal chlorides for 5-HMF production, and resulted in both the highest yield of 83.3% and selectivity of 87.5% in NaCl-aqueous/butanol biphasic system. XRD analysis and FTIR spectroscopy were applied to further characterize the RuCl 3 catalyzed cellulose slurries to reveal the catalytic reaction mechanism. Results demonstrated that RuCl 3 enhanced the decrystallization and cleavage of C O C bonds in cellulose, promoted the subsequent dehydration of glucose into 5-HMF, while suppressed the glucose retro -aldol reaction to byproduct lactic acid. In addition, with the assistance of NaCl-aqueous/butanol biphasic system, 5-HMF further degradation was limited and thusly maintained a desired 5-HMF yield. This proposed approach provides an efficient strategy for one-pot conversion of cellulose into 5-HMF.