Method of processing fusel oil

FIELD: chemistry.

SUBSTANCE: invention relates to chemical engineering and specifically to processing fusel oil, which is a large-tonnage waste in the alcohol industry. Fusel oil from production of ethyl alcohol is processed by esterification with glacial acetic acid in the presence of a sulphuric acid catalyst, and neutralisation, wherein esterification is carried out while boiling the reaction mixture and continuously separating water using a separating flask. The obtained product is separated from the catalyst under a vacuum at temperature not higher than 110°C. The obtained product and the catalyst are separately neutralised and the obtained product is additionally dried.

EFFECT: method enables to process fusel oil into a highly efficient component of mixed solvents of high quality with low cost of production and high output of the product.

4 cl

 

The invention relates to the field of chemical technology, namely the processing of fusel oil, which is the tonnage of waste alcohol industry, and to the production of solvents for paints.

Known modern methods of disposal of fusel oil (GOST 10071-71) suggest or combustion in furnaces in the composition of the oil [Klimovsky DI, Smirnov V.N. The technology of alcohol. M., 1967] or use as raw material for the production of isoamyl alcohol by rectification [RF Patent 2109724, 23.05.96, Gareev GA and others]. In this patent it is assumed again the burning 40% of low-boiling fractions of fusel oil.

Also known is a way to allocate and use all organic ingredients fusel oil [RF Patent 2138476, 27.09.99, Gareev and others]. In this way the principle of multi-stage flash distillation, separation into fractions of the original fusel oil, the use of toluene as an azeotropic agent. To highlight isoamyl alcohol spend three phase rectification. When processing the parent fraction at a temperature of 84°C 20 wt.% cast away, and the following fraction at a temperature 84-87°C (about 15% by weight) are sent for reprocessing. This three stage.

The disadvantages of this method are very energy intensive (six stages), low process speed, bulky is parature design, the use of an expensive reagent toluene (ten times more fusel oil).

A method of refining fusel oil production of ethanol, comprising the esterification of acetic acid in the presence of a catalyst of sulfuric acid, azeotropic drying and neutralization, in which the esterification is carried out at a temperature of 85-115°C, the reaction mixture (product and catalyst) is subjected to neutralization, the resulting product is dried by azeotropic drying, separating the resulting product from the catalyst under vacuum at temperature not above 143°C (see Thesis for the degree of Ph.D. in Mathematical models of parametric synthesis of mixed solvents". Grevtsev A.F., Voronezh, 2002, 170 HP). This method is used for the prototype.

This method makes it possible to dispose of fusel oil, to obtain a mixed solvent with good solubility and a wide range of applications in the coatings industry. However, the method has the following disadvantages:

- stage distillation occurs at a temperature of 140°C and isoamylase, most valuable product boils at t=146°C, so its possible loss, which will increase the cost of the final product; stage azeotropic drying, which is subjected to the product after neutralization, cannot provide a water content of less than wt.%, since the solubility of ethyl acetate in water 12 wt.%, and Solidaritate 2 wt.%. This reduces the quality of the final product and does not meet the standard; the disadvantage of this method is that in the process of esterification (the first stage of the prototype) is not given water. The processes of esterification equilibrium, and it is impossible to obtain high outputs ethers, still water.

To overcome these drawbacks, we propose a new technical solution for processing of fusel oil in a effective component mixed solvents, high quality, low cost and high yield, corresponding to the standard and not inferior in performance to imported product.

This effect is achieved by conducting the esterification of fusel oil production of ethanol glacial acetic acid in the presence of a catalyst of sulfuric acid at boiling of the reaction mixture and continuous water separation using Florentine, separating the resulting product from the catalyst under vacuum at a temperature not exceeding 110 are separate neutralizing the resulting product and the catalyst, and then the resulting product is optionally subjected to drying with anhydrous sodium sulfate, the resulting product is neutralized crystal soda, the remainder of the catalyst is neutralized with caustic.

The way Khujand who have been as follows.

The plant includes a reactor with a stirrer and heating, water cooler, Florentino (flow separator for the separation of water), vacuum part and the receiving container.

The reactor was loaded 620g fusel oil GOST 17071-71, 380 g of glacial acetic acid GOST 61-75 and 20 g of sulfuric acid GOST 2184-77 and was heated to the boiling point of 95°C.

Boil for 45-60 minutes with a full refund phlegmy in the reactor was then connected Florentino and began to separate the water.

Water separated of 100 g of This water, which was contained in fusel oil and water, which was formed by esterification of the alcohols contained in fusel oil.

By the end of the esterification is to stop water excretion. After the termination of allocation of water (35-40 minutes), the reactor was cooled to a temperature of 50-60°With included vacuum and drove obtained the product (esters and the remaining alcohols) in the receiving tank. The distillation of the esters must be made at a temperature not exceeding 110°C in order to avoid acid hydrolysis in Cuba reactor. In Cuba reactor remains exhaust catalyst. For the quality of the product is important to a preliminary separation of product from catalyst with subsequent separate neutralization. The resulting product is spontaneity the solvent was neutralized crystal soda to pH 7, then dried with anhydrous sodium sulfate and filtered. The water content in producten exceeds 0.6 wt.%. The balance of sulfuric acid in the cube reactor was diluted with water and neutralized to pH 7 with caustic.

The product yield is 70-75 wt.%. Such withdrawal is due to the water content of fusel oil.

Justification the boundary conditions of implementation of the method of processing fusel oil.

To implement the method was used in the original substance, the appropriate Standard. The ratio of 62 wt.% fusel oil and 38 wt.% glacial acetic acid is optimal, since the increase in the concentration of glacial acetic acid to 40 wt.% increases the acidity of the resulting product and increases the consumption of soda on stage neutralization and does not increase the number of acetates in the finished product (the maximum number of saponification 452.8 mg/g KOH).

The amount of catalyst was 2 wt%. The increase in the concentration leads to increased consumption of caustic soda at a stage of neutralization and reduction to 1% leads to an increase in the stage of esterification to 90 minutes, as well as increased consumption of sodium sulfate at a stage of dehydration. (The water in the process of esterification interacts with the catalyst of concentrated sulfuric acid and partially held in Cuba reactor).

The temperature of the implementation of the method is 95°C (the boiling of the reaction mixture depends on the composition of fusel oil (GOST-71 and ratio No. 1). If the reactor is not boiling, prozesse flows, because there is not separation of water, and the process of esterification is an equilibrium. The temperature increase leads to an increase in the intensity of the boil and the pressure increase in the reactor and unnecessary consumption of water for cooling.

The resulting product is a highly effective component of mixed solvents with a number of coagulation 95-100 points, the water content is less than 0.6 wt.%, density 0,872, volatility of 18 units, the number of refraction of 1.40. Consists of alcohols and acetates from ethyl to isoamyl alcohols with a maximum number of saponification 452.8 mg/g KOH.

1. A method of processing fusel oil production of ethanol, comprising the esterification of glacial acetic acid in the presence of a catalyst of sulfuric acid, neutralization, characterized in that the esterification is carried out at the boiling reaction mixture and continuous water separation using Florentine, separating the resulting product from the catalyst under vacuum at a temperature not higher than 110°C, subjected to a separate neutralizing the resulting product and the catalyst, and then the resulting product is optionally dried.

2. The method according to claim 1, characterized in that the resulting product is neutralized crystal soda.

3. The method according to claim 1, characterized in that the resulting product is optionally dried with anhydrous sodium sulfate.

4. The method according to claim 1, characterized t is m, the remainder of the catalyst is neutralized with caustic.



 

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