Preparation method of solid catalyst for biodiesel production

Abstract

The invention relates to a preparation method of a solid catalyst for biodiesel production, belonging to the field of oil product processing. The preparation method of a solid catalyst for biodiesel production is characterized by comprising the following steps: (1) preparing phosphotungstic acid: dissolving a certain amount of sodium tungstate hydrate and disodium hydrogen phosphate in boiling water while stirring, adding a certain amount of concentrated hydrochloric acid while continuously stirring, cooling, then adding ethyl ether, and drying to obtain the phosphotungstic acid for later use; and (2) preparing a solid cesium phosphotungstate catalyst: respectively preparing a certain amount of cesium carbonate and the prepared phosphotungstic acid into solutions, adding the cesium carbonate into the phosphotungstic acid solution while stirring, stirring for a certain time, then standing at room temperature for a certain time, and evaporating the water content at a certain temperature to obtain a white solid, namely the solid cesium phosphotungstate catalyst. The solid catalyst prepared by the invention has the following advantages: the solid catalyst has high specific surface area and super high acidity; under the low-temperature reaction conditions, the conversion rate of biodiesel through catalytic preparation can be up to 91% or above; the solid catalyst can be used repeatedly, etc.

Description

technical field [0001] The invention relates to a preparation method of a solid catalyst used for biodiesel production, belonging to the field of oil product processing. Background technique [0002] Biodiesel is a clean and renewable energy. It is a liquid made from oil crops such as soybeans and rapeseeds, oil-bearing forest fruits such as oil palm and pistachio, engineering microalgae and other oil-bearing aquatic plants, animal fats, and waste cooking oil. Fuel is a high-quality petroleum diesel substitute. Biodiesel is a typical "green energy". Vigorously developing biodiesel has important strategic significance for sustainable economic development, promoting energy substitution, reducing environmental pressure, and controlling urban air pollution. [0003] At present, the methods for producing biodiesel generally include homogeneous acid and alkaline catalytic methods. The homogeneous basic catalytic method has high catalytic activity, but it is very sensitive to a s...

AI Technical Summary

Problems solved by technology

The homogeneous basic catalytic method has high catalytic activity, but is very sensitive to a small amount of free fatty acid and moisture in the raw material, and is prone to saponification reaction, resulting in difficulty in the separation of biodiesel products

The homogeneous acidic catalytic method uses sulfuric acid, phosphoric acid, hydrochloric acid and organic sulfonic acid as catalysts, which is easy to corrode equipment and produce a large amount of acid-containing wastewater. The subsequent treatment is complicated and the separation of products is difficult.

In addition, there are some solid acid catalyzed methods for preparing biodiesel, but all of them require a higher temperature (about 230°C) for the transesterification reaction, and the conditions are harsh, so it is not suitable for industrialization.