Method for preparing levorodextrone based on pyrolytic carbon-catalyzed cellulose

Abstract

The invention belongs to the field of biomass energy utilization and particularly relates to a preparation method of a pyrolytic carbon-modified catalyst, and a method for preparing levorodextrone by catalyzing pyrolytic cellulose by using the catalyst. The pyrolytic carbon-modified catalyst is a composite catalyst formed by activating activated carbon generated by pyrolyzation of the cellulose as a carrier by using a sulfuric acid; and the pyrolytic carbon-modified catalyst and the cellulose are quickly catalyzed and pyrolyzed at 300-400 DEG C in an oxygen-free environment in a fixed bed reactor to obtain a liquid product containing levorodextrone. Levorodextrone is high in yield and high in purity. In addition, the catalyst is cheap and easy to prepare, does not need to be separated from a pyrolytic residue of the cellulose, and can be further processed for further use.

Description

technical field [0001] The invention belongs to the field of utilization of biomass energy, and in particular relates to a self-pyrolysis carbon modification catalyst and a preparation method thereof, and a method for preparing levoglucosone by using the catalyst to catalyze pyrolysis of cellulose. Background technique [0002] Levoglucosone (LGO, 1,6-anhydro-3,4-dideoxy-β-D-pyranose-2-one) is an anhydrosugar product formed by pyrolysis of cellulose, and its structure was established in 1973 It is determined. Due to the enone system of 6,8-dioxobicyclo[3.2.1]octane, highly active ketone group and acetal center, L-glucosone can participate in a variety of synthetic reactions, such as the synthesis of various sugars and non- Chiral raw materials for carbohydrate derivatives. In addition, L-glucosone can also be used in the synthesis of various drugs for the treatment of cancer, immune diseases and heart diseases. At present, there is no large-scale production of levoglucoso...

AI Technical Summary

Problems solved by technology

However, most catalysts are not very selective for the formation of L-glucosone

Debele et al. reported in Application of catalysts forobtaining 1,6-anhydrosaccharides from cellulose and wood by fast pyrolysis that pyrolysis of cellulose was catalyzed by phosphoric acid on pyrolysis-chromatography / mass spectrometry (Py-GC / MS). LGO, up to 30% selectivity, impregnated with Fe 3+ It can increase the output of LG and LGO, but the process is more complicated and will bring certain environmental pollution problems; Lu et al. in "Catalytic fast pyrolysis of cellulose and biomass to produce levoglucosenone using magnetic SO 4 2- / TiO 2 -Fe 3 o 4 " and "Using solid superacid to catalyze the pyrolysis of cellulose to prepare L-glucosone" reported that the use of solid superacid, TiO 2 , ZrO 2 , SO 4 2- / ZrO 2 , SO 4 2- / TiO 2 and SO 4 2- / TiO 2 -Fe 3 o 4 The experimental study on the preparation of LGO by catalytic pyrolysis of cellulose on Py-GC / MS found that they all can promote the formation of LGO, among which SO 4 2- / TiO 2 Under catalysis, the selectivity of LGO reaches 60% at 350 °C, and the yield reaches the highest at 400 °C

However, the vast majority of current research is carried out on Py-GC / MS, and the biomass feed is basically less than 1 mg, and the pyrolysis characteristics obtained are comparable to those obtained in practice in commercial devices such as fixed-bed and fluidized-bed reactors. A big difference

In addition, these catalysts are all inorganic materials, the preparation process is complicated, the price is relatively expensive, and they need to be separated from the generated pyrolytic carbon.