Method for preparing levulinic acid from hexabasic sugar catalyzed and hydrolyzed by fire resistant and highly acidic resin

Abstract

This invention discloses a method for preparing levulinic acid by hydrolyzing hexamylose catalyzed by heat-resistant strong-acidic resin. The method comprises: (1) adding 10-400 g/L hexamylose aqueous solution and heat-resistant strong-acidic resin at a weight ratio of (2-20):1 into a pressure reaction kettle, sealing, stirring, heating to boiling under normal pressure, and evacuating for 2-5 min; (2) heating to 120-180 deg.C, and hydrolyzing for 2-16 h; (3) cooling the hydrolysis product to obtain hydrolysis solution. The method utilizes heat-resistant strong-acidic resin as a substitute for liquid inorganic acid as the catalyst, and has such advantages as mild reaction conditions, easy separation of the catalyst, recoverable catalyst, high catalytic activity, and high levulinic acid yield. The method is environmentally friendly, and can avoid the problems of difficult recovery of catalyst, serious pollution and serious corrosion faced by the method utilizing inorganic acid catalyst.

Description

technical field [0001] The invention relates to a method for preparing levulinic acid by using a high-temperature resistant strong acid resin to catalyze and hydrolyze hexavalent sugar. Background technique [0002] Levulinic acid, also known as 4-oxopentanoic acid, levulonic acid or valeric acid, contains a carbonyl group, a carboxyl group and α-hydrogen in its molecule, and its activity is very high, and the hydrogen atoms on its different functional groups have different activities , so it has good reactivity, and can participate in the reaction as both carboxylic acid and ketone. Through esterification, halogenation, hydrogenation, oxidative dehydrogenation condensation and other chemical reactions, various useful compounds and new polymer materials can be prepared, including resins, medicines, pesticides, spices, solvents and inks; at the same time it The carbonyl group at position 4 is a latent chiral group, and chiral compounds can be obtained through asymmetric redu...

AI Technical Summary

Problems solved by technology

[0006] As mentioned above, liquid inorganic acids (mainly sulfuric acid and hydrochloric acid) are currently used as catalysts in the preparation of levulinic acid. This process has the disadvantages of difficult catalyst recovery, large pollution, and serious corrosion in the process of inorganic acid catalysis.

ZL200510023259.9 proposes a method of using molecular sieves to catalyze the hydrolysis of glucose to produce levulinic acid. However, molecular sieve catalysts have the fatal disadvantage of poor water resistance. Therefore, in the process of using molecular sieves to catalyze the hydrolysis of glucose to produce levulinic acid, molecular sieve catalysts are difficult to reuse.