RU2227795C1 - Method for preparing higher saturated chlorinated acids - Google Patents

Abstract

FIELD: organic chemistry, chemical technology. SUBSTANCE: invention relates to a new method for preparing higher saturated chlorinated acids of the general formula: R(CHCl)_nCOOH wherein R is aliphatic hydrocarbon radical comprising 9-22 carbon atoms; n = 1-4. These compounds are important products of chemical industry and can be used, for example, as intermediate products in manufacturing plasticizing and stabilizing additions. Method involves oxidation of chloroparaffins in the presence of catalytic system comprising stearic, acetic acids and an aqueous solution of alternating valence metal alkaline salt manganese salt taken in the amount 7-8 wt.-%. Chloroparaffins are mixed in the presence of air oxygen with catalytic system at temperature 120-125 C and oxidation is carried out with air oxygen at temperature 105-11 c, under atmosphere pressure for 30-32 h. Technological method is simple in equipment shaping, allows using cheap raw and soft conditions for carrying out the process. EFFECT: improved preparing method. 4 tbl, 2 ex

Description

The method for producing higher fatty chlorinated acids relates to the chemistry of derivatives of chlorinated hydrocarbons, namely, to a new method for producing higher fatty chlorinated acids of the general formula: R (CHCl) _n COOH, where R is an aliphatic hydrocarbon radical, n = 1-4, which are important products chemical industry.

A known method of producing monochloroacetic acid, which consists in the oxidation of ethylenechlorohydrin with nitric acid. The ratio of ethylene chlorohydrin: HNO ₃ = 1: 4 (A.S. No. 173221, C 07 C 53/16, 1965).

The disadvantages of this process are the possibility of obtaining only monochloracetic acid by this method, as well as the use of 96-98% nitric acid as an oxidizing agent, the preparation of which is quite expensive.

A known method for producing monochloracetic acid by photooxidation of 1,2-dichloroethane (and.with. No. 1004346, C 07 C 53/16, C 07 C 5/215, 1983).

The disadvantages of this process are the possibility of obtaining only monochloroacetic acid in this way, additional complication of the design for irradiating the reactor, and the explosiveness of the oxygen-chlorine mixture used.

Closest to the proposed invention is a method for producing monochloracetic acid by ozone oxidation of 1,4-dichlorobutene-2 (Japanese Patent No. 47-30166, CL 16 B. 64, C 07 C, 1972).

The disadvantages of this method are the ability to obtain in this way only monochloracetic acid, and the oxidizing agent-ozone must be obtained additionally.

The objective of the invention is to develop a technologically advanced method for producing higher fatty chlorinated acids, namely, a method that is simple in hardware, using inexpensive raw materials and applying mild conditions for carrying out the proposed process.

The technical result is the possibility of obtaining higher fatty chlorinated acids of the claimed method.

The technical result achieved is achieved in a new method for producing higher fatty chlorinated acids of the general formula R (CHCl) _n COOH, where R is an aliphatic hydrocarbon radical containing 9-22 carbon atoms, n = 1-4, by oxidation of chloroparaffins in the presence of a catalytic system containing stearic, acetic acid and an aqueous solution of an alkali metal salt of variable valency - manganese salts, in the amount of 7-8 wt.%, while chlorine paraffins are mixed in the presence of atmospheric oxygen with a catalytic system at a temperature of 120-125 ° C, and ok Ischelation is carried out with atmospheric oxygen at a temperature of 105-110 ° C and atmospheric pressure for 30-32 hours.

The essence of the method is the reaction of obtaining higher fatty chlorinated acids by oxidation:

The advantage of this method is the possibility of obtaining a wide range of higher fatty chlorinated acids, which are important intermediates in the chemical industry (production of plasticizing and stabilizing additives to polymeric materials).

The method is as follows:

The stage of obtaining higher fatty chlorinated acids is as follows. To the initial chloroparaffin, a catalytic mixture (stearic and acetic acids and an aqueous solution of potassium permanganate) is added in an amount of 7-8 wt.% And air oxygen is passed for 2 hours at atmospheric pressure and a temperature of 120-125 ° C to form a catalytic complex, and then they pass air oxygen at atmospheric pressure and a temperature of 105-110 ° C for 30 hours. The resulting mixture of higher fatty chlorinated acids in chlorinated paraffin without further purification and separation can be used in the chemical industry. The content of oxidation products in chloroparaffin is 15-20%.

As the studies showed, the optimal technological conditions for the process of oxidation of chlorinated hydrocarbons by atmospheric oxygen is its implementation in the environment of the initial chloroparaffin when using the catalyst in an amount of 7-8 wt.%. A smaller amount of catalyst leads to a decrease in the content of the oxidation product in chloroparaffin during the same process time. A larger amount of catalyst does not lead to an increase in the content of the oxidation product in chloroparaffin for the same process time.

Optimal for the reaction is a temperature of 105-110 ° C. A decrease in temperature leads to a significant increase in the duration of the oxidation process, and its further increase leads to a change in color, and an increase in temperature does not increase the content of oxidation products in chlorine paraffin and does not reduce the time of the oxidation process.

Reducing the duration of the oxidation process does not allow to achieve the required content of oxidation products in chloroparaffin, and its increase does not give a significant increase in the content of oxidation products in chloroparaffin.

The oxidation depth of the initial chloroparaffin was controlled by acid number. Acid number was determined by the method of TU 38. 301.-29-57-93.

The structure of the obtained compounds is confirmed by IR spectroscopy. The IR spectra of chlorine paraffins CP-30, CP-250 contain the following absorption bands (cm ^-1 ): 2920 stretching vibrations of CH; 1468.1392-deformation vibrations CH; 896-deformation vibrations (-CH ₂ -) _n- CH ₃ ; 788, 724, 652, 604-stretching vibrations of С-Сl. The IR spectra of the oxidation products of chlorine paraffins HP-30, HP-250 contain the following absorption bands (cm ^-1 ): 2920 stretching vibrations of CH; 1460, 1380-deformation vibrations CH; 1776, 1716-stretching vibrations С = O, 732-pendulum vibrations (-CH ₂ -) _n , 660, 608-stretching vibrations С-Сl.

The invention is illustrated by the following examples:

Example 1

Oxidation of a sample of chloroparaffin HP-30.

9 g (7-8 wt.%) Of a catalytic mixture (stearic and acetic acids and an aqueous solution of potassium permanganate) are added to 100 g of a sample of chloroparaffin of the HP-30 brand and air oxygen is passed for 2 hours at a temperature of 120-125 ° С at atmospheric pressure for the formation of the catalytic complex, and then the oxidation process is carried out at a temperature of 105-110 ° C, at atmospheric pressure and constant bubbling of oxygen through the reaction mixture for 30 hours. The acid number of the mixture after 32 hours is 47 mgKOH / g, which corresponds to 20 % oxidate in medium x orparafina HP-30.

The fractional composition of chloroparaffin KP-30 and its oxidation products was studied. The data are given in table. 1 and table 2.

Example 2

Oxidation of a sample of chloroparaffin HP-250.

9 g (7-8 wt.%) Of a catalytic mixture (stearic and acetic acids and an aqueous solution of potassium permanganate) are added to 100 g of a sample of chlorine paraffin brand ХП-250 and air oxygen is passed for 2 hours at a temperature of 120-125 ° С at atmospheric pressure for the formation of the catalytic complex, and then the oxidation process is carried out at a temperature of 105-110 ° C, at atmospheric pressure and constant bubbling of oxygen through the reaction mixture for 30 hours. The acid number of the mixture after 32 hours is 35 mgKOH / g, which corresponds to 15 % oxidate in medium x lorparaffin HP-250.

The fractional composition of chloroparaffin KP-250 and its oxidation products was studied. The data are given in table. 3 and tab. 4.

The proposed method allows to obtain higher fatty chlorinated acids with a different number of carbon atoms in the chain.

The advantage of the proposed method is its versatility, the use of a cheap oxidizing agent and ease of design.

Thus, the above information indicates the following conditions are met when using the claimed invention: the agent embodying the claimed invention when used is intended for use as intermediates in the manufacture of plasticizing and stabilizing additives for polymeric materials; for the claimed invention in the form described in the claims, the possibility of its implementation using the means and methods described in the application and known prior to the priority date is confirmed; the means embodying the claimed invention in its implementation is capable of ensuring the achievement of a technical result.

Therefore, the claimed invention meets the requirement of "industrial applicability".

Claims (1)

The method of obtaining higher fatty chlorinated acids of the General formula R (CHCl) _n COOH, where R is an aliphatic hydrocarbon radical containing 9-22 carbon atoms; n = 1-4, by oxidation of chloroparaffins in the presence of a catalytic system containing stearic, acetic acid and an aqueous solution of an alkali metal salt of variable valency - manganese salt, in the amount of 7-8 wt.%, while chlorine paraffins are mixed in the presence of atmospheric oxygen with a catalytic system at a temperature of 120-125 ° C, and oxidation is carried out with atmospheric oxygen at a temperature of 105-110 ° C and atmospheric pressure for 30-32 hours