Method for synthetizing biological diesel oil by oil and fat materials

Abstract

A process for synthesizing biologic diesel oil from raw oil material features that the short-chain ester of fatty acid (methyl acetate or ethyl acetate) is used as acyl receptor and the biologic enzyme is used to catalyze the transesterifying reaction of oil, and includes such steps as transesterifying reaction between said ester of fatty acid and oil to obtain biologic diesel oil and glyceride triacetate, and reaction between said glyceride triacetate and methanol to obtain short-chain ester for fatty acid for cyclic use.

Description

technical field [0001] The invention belongs to the field of bio-oil synthesis, and in particular provides a method for synthesizing bio-diesel from oil and fat raw materials. Use short-chain fatty acid esters as acyl acceptors, and use biological enzymes to catalyze bio-oils for transesterification to produce biodiesel; the by-product triacetin is further reacted with methanol to obtain the above-mentioned short-chain fatty acid esters, and the resulting short-chain fats Esters can be recycled for biodiesel synthesis. Background technique [0002] The long-chain fatty acid esters produced by the transesterification reaction of bio-oil raw materials are a new type of pollution-free renewable energy, called biodiesel. Its combustion performance is comparable to that of traditional petroleum diesel, because the harmful substances in the exhaust gas emitted by the engine after combustion of biodiesel are 50% lower than that of traditional petrochemical diesel. At present, the...

AI Technical Summary

Problems solved by technology

There are some unavoidable disadvantages in the preparation of biodiesel by chemical method: ① The free fatty acid and water in the oil raw material seriously affect the progress of the reaction; ② The solubility of methanol in oil is not good, which easily leads to the formation of emulsion and complicates the subsequent treatment process ; ③ The process requires that the amount of methanol used greatly exceeds the reaction molar ratio, and the evaporation and reflux of excess methanol increases the energy consumption of the process

These acyl receptors seriously affect the enzyme reaction activity, reduce the service life of the enzyme, and the reaction by-product glycerol is very easy to attach to the surface of the enzyme molecule, affecting mass transfer; at the same time, before the enzyme is reused, some special treatment is required for the enzyme ( For example, the use of organic solvents to wash the by-product glycerin, etc.) can partially restore the activity of the enzyme. The use of a large amount of organic solvents not only increases the cost of the entire production process, but also brings certain difficulties to the operation control of large-scale production.

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