(726b) Kinetics of 5-(hydroxymethyl)Furfural Production From Aqueous Glucose Solution By Using AlCl3 Combined With Brönsted Acid Catalysts

Kinetics of 5-(hydroxymethyl)furfural Production from Aqueous Glucose solution by Using AlCl₃ Combined with Brönsted acid catalysts

Ximing Zhang, Nathan S. Mosier

5-Hydroxymethyfurfural (HMF) is a platform chemical for producing a variety of fuels and polymers that can be manufactured from lignocellulose. We report the use of hydrochloric acid and maleic acid separately mixed with a Lewis acid (aluminum chloride) to catalyze the conversion of glucose to HMF between 140-180℃. A kinetic analysis of aldose- to-ketose isomerization and dehydration/hydrolysis reactions is presented. The kinetic model consists of four reactions: (1) glucose/fructose isomerization; (2) dehydration of sugars to HMF; (3) degradation of sugars to humins; and (4) HMF hydrolysis to levulinic and formic acids. The primary results shows that in a single, aqueous phase without adding Brönsted acid, the highest HMF yield reach 40% at the condition of 180℃, 4mins, AlCl₃ 0.1mol/L. An apparent activation energy barrier of 115KJ/mol is estimated for glucose isomerization from the initial kinetics. When HCl and Maleic acid is introduced at amount of 0.1 mol/L, the HMF yield reach 44% and 40% respectively with a shorter time, 3 minutes. The results illustrates the acceleration of fructose dehydration rate to HMF when external Brönsted acidity is added.