59results about "Anhydrosugars" patented technology

The invention belongs to the field of biomass energy use and particularly relates to a levoglucosenone preparation method. The levoglucosenone preparation method includes: mechanically mixing char sulfonic acid or magnetic char sulfonic acid serving as a catalyst with biomass raw materials, performing fast pyrolysis at the temperature of 280-450 DEG C under the anaerobic condition, and condensing pyrolysis gas so that a liquid product rich in levoglucosenone can be obtained. In the liquid product prepared by the method, both yield and purity of the levoglucosenone are high; and the catalyst is stable in performance, can be directly separated and recovered from solid residues mechanically or by the aid of a magnetic field and is reusable.

The invention discloses a preparation method of levoglucosenone. The preparation method comprises the following steps of firstly, dissolving phosphoric acid in water to form a phosphoric acid solution; adding cellulose or cellulose-contained biomass, mixing and soaking; filtering the soaked cellulose or cellulose-contained biomass, pressing and extruding or centrifuging, and performing pyrolysis pretreatment on the treated matter, so as to obtain a dewatered intermediate product; cooling the obtained dewatered intermediate product to room temperature, cooling, putting into a sodium hydroxide or potassium hydroxide water solution, and fully mixing and soaking; filtering the mixed and soaked product, pressing and extruding or centrifuging, performing non-oxygen pyrolysis on the treated product, and collecting condensate in the pyrolysis process, so as to obtain a pyrolysate containing the levoglucosenone. The preparation method of the levoglucosenone has the advantages that by adopting two-step reaction, the yield rate is greatly increased and reaches about 40%; compared with the prior art, the cost is greatly reduced; by adopting the technical scheme, the large application prospect is realized.

A method for alkylation of an anhydrosugar compound in which a dialkyl carbonate is reacted with an anhydrosugar compound in the presence of a solid phase basic catalyst. A typical anhydrosugar compound is anhydrosugar alcohol, a dianhydromonoether and mixtures thereof. The reaction step uses zeolyte as the solid phase basic catalyst. The zeolite catalyst is typically a zeolite having ammonium groups. The reaction is carried out at a temperature below 240° C. and the reaction time is 2 hours or less.

The present invention relates to a disaccharide intermediate and a synthesis method thereof, relates to the chemical pharmaceutical field, and more specifically relates to a method for preparing a disaccharide segment of a key intermediate for chemically synthesizing heparin and heparinoid compounds. Disclosed are a new disaccharide intermediate and three methods for synthesizing the disaccharide intermediate, that is, compounds of a formula (4) and glucopyranose protected by different anomeric carbon are made to react in the presence of an active agent, to obtain the disaccharide intermediate. According to the technical solutions of the present invention, synthetic raw materials are easy to obtain, have a mild reaction condition, and are suitable for industrialized production.

The invention belongs to the field of utilization of biomass energy, and in particular relates to a method for preparing L-glucosone by catalytic pyrolysis of biomass. The invention uses biomass-based phosphoric acid-activated activated carbon as a catalyst, and through mechanical mixing with biomass, rapid pyrolysis is carried out at 250-470°C under inert and oxygen-free conditions, and rich L-glucose can be obtained after condensing the pyrolysis gas The liquid product of ketones. Biomass-based phosphoric acid activated activated carbon catalytic pyrolysis of biomass pyrolysis products, the yield and purity of glucosone are high; in addition, the mixture of solid coke and catalyst generated by pyrolysis can be used as a carbon source to continue to prepare activated carbon ; By using low-cost and reusable biomass-based phosphoric acid-activated activated carbon, the production cost and pollution can be effectively reduced, and it is an economical and effective method for preparing L-glucosone.