Method for preparing biodiesel by catalysis of rare-earth oxide mesoporous material

Abstract

The invention discloses a method for preparing biodiesel by the catalysis of a rare-earth oxide mesoporous material. In the method, the biodiesel is prepared by reacting vegetable oil serving as a raw material with methanol or ethanol and adding a certain amount of catalyst under the action of esterification and ester exchange. The method comprises the following steps of: adding the vegetable oil and the methanol or the ethanol into a high-pressure reaction kettle, wherein a mass ratio of the vegetable oil to the methanol or the ethanol is (0.2-2):1; adding the rare-earth oxide mesoporous material in an amount which is 1 to 20 percent of the mass of the vegetable oil, and stirring mechanically at the temperature of between 60 and 240 DEG C to perform ester exchange reaction for 1 to 5 hours; after reaction is finished, performing suction filtration while the mixture is hot, and separating a rare-earth oxide mesoporous catalyst from the mixture; distilling a liquid phase to recover the methanol or the ethanol; and transferring the liquid phase to a separating funnel, and standing, so that the upper layer is coarse biodiesel, and the lower layer is glycerol serving as a byproduct. The production process is simple, the catalytic activity is high, the catalyst can be recycled, the aftertreatment is convenient, and industrial waste water is avoided.

Description

technical field [0001] The invention relates to the technical field of green and renewable energy, in particular to a new method for preparing biodiesel, in particular to a method for preparing biodiesel by catalyzing a rare earth oxide mesoporous material. Background technique [0002] Biodiesel refers to organic fatty acid methyl ester or ethyl ester fuel obtained by reacting vegetable oil or animal oil with methanol or ethanol through transesterification. It is a renewable, biodegradable and environmentally friendly biofuel. Its performance is close to that of traditional petrochemical diesel, and it has the characteristics of less pollution. It is an excellent substitute for traditional petrochemical diesel. At present, the process route of biodiesel preparation in industrial production generally adopts a two-step homogeneous catalysis method. The first step is to use H 2 SO 4 Isohomogeneous acid catalyst, pretreat the raw material oil containing high free fatty acid...

AI Technical Summary

Problems solved by technology

However, in the homogeneous method, there is a problem that the pretreatment catalyst is difficult to separate. At the same time, a large amount of industrial wastewater will be generated in the posttreatment process, which is easy to cause environmental pollution and other shortcomings.

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