A method for preparing biodiesel by homogeneous catalysis of solubilized and easily separated ionic liquid

Abstract

The invention discloses a method for preparing biodiesel by homogeneous catalysis of solubilizing and segregative ionic liquid. The method comprises the following steps: adding a methanol substance and oil to a reaction kettle; then adding a butyl triethyl ammonium p-toluenesulfonate ionic liquid catalyst accounting for 10-20% of the total mass of reactants; stirring the substances in the reaction kettle for reaction so as to form a mixture containing the biodiesel; cooling the mixture in a water bath, and standing for layering, wherein an upper layer phase is the biodiesel and trace methanol, and is distilled for methanol removal to form a target product, and a lower layer phase is a mixture of glycerol, the butyl triethyl ammonium p-toluenesulfonate ionic liquid catalyst and excessive methanol; and recycling the butyl triethyl ammonium p-toluenesulfonate ionic liquid catalyst. The method is ingenious in design, simple and convenient in technological operation, and high in reaction speed and conversion rate; the product is easy to separate and purify; the ionic liquid catalyst is low in cost and corrosivity, reusable, and environmentally friendly; the biodiesel can be prepared quickly; the production cost is lowered; and the method has better industrial application prospect.

Description

[0001] Technical field: [0002] The invention relates to the field of biochemical industry, in particular to a method for preparing biodiesel by homogeneous catalysis of solubilized and easily separated ionic liquid. [0003] Background technique: [0004] my country is the largest developing country with the fastest economic development in the world. Economic development is inseparable from energy support, but my country's petroleum energy is relatively short, and the low efficiency of coal energy utilization and the resulting environmental pollution are becoming important factors that plague the sustainable development of my country's economy and society. In this context, the research and development of various biomass energy sources, including biodiesel, has become one of the hot topics to solve the energy crisis and environmental pollution problems. Biodiesel contains no sulfur and aromatic hydrocarbons, has high cetane number and good lubricity, and is a high-quality cle...

AI Technical Summary

Problems solved by technology

[0010] The purpose of the present invention is to provide a method for preparing biodiesel by homogeneous catalysis of solubilized and easily separated ionic liquids. The ionic liquid with good solubility of grease and short-chain alcohol is not only used as a catalyst for the reaction but also as a solubilizer for the substrate. After the reaction is completed, the ionic liquid becomes a solid and is automatically separated by cooling, which solves the problem of the ionic liquid on the substrate in the prior art. Poor solubility, oil and short-chain alcohols are basically immiscible, the reaction rate is slow, the reaction time is long, and the ionic liquid is liquid at room temperature, it needs to be distilled to recover the ionic liquid catalyst, it is difficult to separate and reuse, and the post-treatment process is long.