Method for preparing hydroxymethyl-furfural from glucide under low temperature and normal pressure

Abstract

The invention provides a method for preparing hydroxymethylfurfural by saccharide at low temperature and normal pressure. The method comprises the following steps: mixing a saccharide raw material and a reaction solvent in a mass ratio of 1:3-50; heating the mixed solvent to a temperature of between 100 and 180 DEG C; adding a catalyst which is 0.01 to 2 percent of the mass of the solvent; reacting in an atmosphere of inert gas protection for 30 minutes to 10 hours; cooling a reaction system; extracting the hydroxymethylfurfural by an organic solvent, and generating the hydroxymethylfurfural by reaction; drying the hydroxymethylfurfural by distillation; and crystallizing the hydroxymethylfurfural to obtain the product. The method has the advantages of high selectivity, high yield, and low cost.

Description

technical field [0001] The invention relates to a method for preparing hydroxymethylfurfural. technical background [0002] The huge demand for energy around the world, the instability of oil production, and global warming have once again stimulated people's interest in renewable energy. Biofuels have become the primary "new force" and have attracted the attention of researchers at home and abroad. The reserves of biofuels are huge. It is estimated that the annual energy stored in plants is about 10 times that of the world's main fuel consumption, while the utilization of energy as energy accounts for less than 1% of the total. [0003] The currently widely used biofuels are ethanol and biodiesel, among which the annual production of ethanol in the United States and Brazil both exceeds 10 million tons. With the increase of ethanol production, the production of bioethanol using sugar or grain as raw material is limited by food resources, and it is difficult to meet the needs...

AI Technical Summary

Problems solved by technology

The current methods all need to be carried out under high temperature (above 180°C) and high pressure. Because hydroxymethylfurfural contains a hydroxymethyl group and an aldehyde group, its chemical properties are active, and it is extremely resistant to acid-base, high temperature, and water environments. Stable, it will further dehydroxymethyl furfural or generate levulinic acid or polymerize to generate humic substances and other substances, resulting in extremely low selectivity and yield of generating hydroxymethyl furfural, which cannot meet production requirements

In addition, conventional solvents such as water and methanol require a certain pressure to ensure the liquid state of the reaction medium at relatively high temperatures and maintain stable operation of the reaction. This not only increases production costs, but also poses safety hazards, and at the same time, the process parameters are difficult to control.