Method for refining biological oil by homogeneous catalysis

Abstract

The invention discloses a method for refining biological oil, comprising the following step: carrying out catalytic cracking reaction and catalytic hydrogenation reaction on biological oil in a low molecular alcohol system under the catalysis of a homogeneous catalyzer in a hydrogen environment. The invention successfully transforms acid, aldehyde and low polymers in the biological oil into ester, alcohol and small molecule fuel components by utilizing the homogeneous catalyzer to catalyze and refine the biological oil in a subcritical system of low molecular alcohol, thereby greatly reducingthe acidity of the biological oil and the condensation and polycondensation reaction speed, overcoming the phenomenon of biological oil coking during the refining process, greatly increasing the thermal stability of the biological oil and the refined oil yield and solving the problem existing in preparing liquid fuel by biomass pyrogenation, therefore, the industrial development of preparing the liquid fuel by biomass pyrogenation is promoted, which has a significant meaning of establishing a sustainable energy system and protecting ecological environment.

Description

technical field [0001] The invention relates to a method for refining bio-oil, in particular to a method for homogeneously catalytically refining bio-oil. Background technique [0002] Biomass pyrolysis to produce bio-oil is considered to be one of the better technologies to solve the current energy and environmental crisis, especially the shortage of liquid fuel. Biomass pyrolysis liquefaction technology has developed rapidly since its advent in the 1980s. A variety of pyrolysis reactors have been researched and developed internationally, and some have entered the demonstration application stage. 100 tons of sawdust pyrolysis liquefaction industrial demonstration plant, the yield of bio-oil is above 60wt%, and the oil is used for combustion to generate electricity. [0003] Since Shenyang Agricultural University first carried out research on biomass pyrolysis and liquefaction in the mid-1990s in my country, this technology has made great progress. , successfully developed ...

AI Technical Summary

Problems solved by technology

Although there are many detailed studies on catalytic hydrogenation and catalytic cracking of bio-oil, both of which have many advantages, most of the catalysts used at home and abroad are traditional solid-state catalysts, which are far from suitable for complex systems such as bio-oil.

The main reasons are: firstly, the solid catalyst used has poor oil solubility, the catalyst cannot fully contact with the bio-oil, and the catalytic efficiency is low; secondly, the bio-oil contains a large amount of heat-sensitive and macromolecular substances, which are prone to condensation and polycondensation reactions. When it exceeds 80°C, the polymerization reaction in the bio-oil is very strong, and the catalysts currently used are all high-temperature catalysts, the condensation polycondensation reaction is strong, and the reaction components will enter the catalyst matrix, block the catalyst pores, cover the catalyst active center, and cause the catalyst Inactivation; again, the components in bio-oil are complex, and the hydrogenation reactivity of different components varies greatly, and the components with high hydrogenation reactivity have higher activity of condensation and polycondensation at higher temperatures

[0006] Catalytic cracking and catalytic hydrogenation are the most researched bio-oil refining methods at present. Both of them have many advantages. However, most of the catalysts used at home and abroad are traditional solid-state catalysts, which are far from suitable for complex systems such as bio-oil. Because: the catalyst cannot fully contact with the bio-oil, the catalyst is a high-temperature type, the coking of the bio-oil is serious, the pores of the catalyst are easily blocked by macromolecules in the bio-oil, and the catalyst is seriously deactivated