Residual oil treatment method for recovering sterol

Abstract

The invention provides a residual oil treatment method for recovering sterol, which comprises the following steps: heating potassium hydroxide and methanol for reflux, and reacting to obtain a mixed solution, wherein the heating reflux temperature is 65 DEG C, and the heating reflux time is 4 hours; mixing residual oil and the mixed solution for transesterification, and a transesterification product is obtained, wherein the temperature of the transesterification reaction is 80 DEG C, and the time is 4 hours; acidifying the transesterification product, and standing for separation to obtain an upper-layer oil phase and a lower-layer water phase; carrying out water washing treatment on the upper-layer oil phase, and then standing for separation to obtain a water washing solution and a secondupper-layer oil phase, wherein the temperature of the water for washing treatment is 80 DEG C; combining the lower-layer water phase and the water washing liquid, and then carrying out evaporation separation to respectively obtain water, methanol, crude potassium salt and glycerol; washing and drying the crude sylvite to obtain refined sylvite; and sequentially carrying out cold separation crystallization, filtration and refining treatment on the second upper-layer oil phase to obtain the refined sterol. The method is low in sterol recovery cost.

Description

[0001] This application is a divisional application, the original application number is: 201911137630.2, the application date: November 19, 2019, the title of the invention: a method for treating residual oil by recovering sterols and refining potassium salts. Technical field [0002] The invention relates to the technical field of biochemical industry, in particular to a method for treating residual oil for recovering sterols. Background technique [0003] During the production and refining of food oils such as soybean oil, rapeseed oil, peanut oil, sunflower oil, palm oil, etc., a large amount of deodorized distillate, the so-called vegetable oil scraps, is produced. In fact, the deodorized distillate also contains a large number of useful ingredients, such as natural vitamin E, sterols and other very valuable products can continue to be extracted from the deodorized distillate. At present, most of the treatment processes for deodorized distillate at home and abroad are: the deo...

AI Technical Summary

Problems solved by technology

[0004] The residual oil after vitamin E extraction generally accounts for 10% to 20% of the raw oil, and these residual oils still contain a small part of useful components, among which the content of sterol esters is about 10% to 11% of the residual oil , the glyceride content reaches about 2% to 3% of the residual oil; at present, these residual oils are mostly discharged as waste residues, causing great pollution to the environment

Sodium hydroxide and sodium carbonate are generally used as catalysts in the existing residual oil treatment methods, and the sodium salts produced in the process flow have no practical value, and due to the imperfect treatment methods, there is still the phenomenon of emission pollution

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