Production enhancement of 5-hydroxymethyl furfural from fructose via mechanical stirring control and high-fructose solution addition

BACKGROUND5-hydroxymethylfurfural (HMF) has attracted increasing attention so that an efficient process for HMF production from high-sugar solution is needed for the successful commercialization of this versatile intermediate in the production of high value chemicals. RESULTSTwo simple operations, mechanical stirring control and high-fructose solution addition, were applied to the water/butanol system for enhancing fructose-to-HMF reaction using HCl as catalyst. The optimization of stirring speed led to a high HMF yield of 81.7% with 92.0% fructose conversion (0.3 moL L-1 HCl, 1000 rpm). Moreover, a reasonable mechanism describing the effect of stirring speed on HMF yield was proposed. During the process of high-fructose solution (54.6 wt%) addition, the yields of HMF after four additions in every experiment all exceeded 55%, and a HMF yield of 83.3% was achieved after three additions at 1000 rpm. CONCLUSIONSThe optimization of mechanical stirring in aqueous/butanol media led to a high HMF yield. By studying the kinetics of the fructose-to-HMF reaction, it was demonstrated that a low value of reaction rate constant is of benefit to obtain high HMF yield for this biphasic system. The simple addition process greatly reduced the side-reaction and made the operation more continuous and stable, and thus provided a practical and effective method of HMF preparation in high-fructose solution. (c) 2013 Society of Chemical Industry