Method for preparing polyol from waste grease and application thereof

Abstract

The invention discloses a method for preparing polyol from waste grease, comprising the following steps: a solid acid catalyst which has large hydrophobic surface and has both a sulfonic group and a carboxylic group is adopted to catalyze esterification and transesterification between waste grease and methanol so as to convert waste grease to fatty acid methyl ester and a by-product glycerin; saturated fatty acid ester in fatty acid methyl ester is separated; under the catalysis of a dual acid site solid acid and in cooperation of the dual acid site, 30% hydrogen peroxide is directly catalyzed for epoxidation of fatty acid methyl ester, an intermediate product is not separated, and the by-product glycerin is added for ring opening of alkoxylation after direct heating-up; and finally, filtration is carried out to recycle the catalyst, and reduced pressure distillation is carried out to remove water so as to obtain biological oil-based polyol. According to the method, waste grease is used as a raw material, thus turning waste into wealth. The polyol product obtained has good biodegradability; the preparation process is green; emission of three industrial wastes is low; product structure and hydroxyl value can be adjusted; the range of application is wide; and the level of effect on the environment is low.

Description

technical field [0001] The invention relates to a method for preparing polyol from waste oil and its application, and belongs to the technical field of organic chemical synthesis. Background technique [0002] Polyurethane materials have excellent performance and wide range of uses. my country has become the fastest-growing market for polyurethane in the world, and significant progress has been made in product research and development, production, and application. Among all kinds of polyurethane products, polyurethane foam is the most widely used, and has huge development space in the fields of building energy saving, solar water heaters, imitation wood furniture, pipe insulation, potting and so on, and the market demand is strong. Traditional polyurethane polyols are generally polyoxyalkylene polyols with high functionality and high hydroxyl value (low molecular weight), namely "polyether polyols". Polyether polyols are usually prepared by ring-opening polymerization of h...

AI Technical Summary

Problems solved by technology

In 2011, the total consumption of edible oil in my country reached 27.65 million tons, of which the self-sufficiency rate was only 38.1%. Grain and oil safety has become an issue that needs to be paid attention to in my country. Therefore, it is not realistic to directly use edible oil in large-scale industrial production

Catering waste oil is seriously polluted, and oily waste water often leads to blockage of sewage pipe network, which brings difficulties to sanitation work; if waste oil flows directly to rivers, it will deteriorate the water body, which is extremely unfavorable to the environment and ecology