CS232643B1 - Method of purifying 2-isopropylamino-4-ethylamino-6-chlorine-s-triazine - Google Patents

Abstract

The invention provides for the purification of 2-isopropylamino- -4-ethylamino-6-chloro-s-triazine contaminated organic and inorganic substances. Contaminated 2-isopropylamino-4-ethylamino- The 6-chloro-s-triazine is dissolved and / or melted in a water-soluble organic solvent at the boiling point of the mixture, insoluble the impurities are separated and the solvent is distilled off from 2-isopropylamino-4-ethylamino- 6-chloro-s-triazine with water vapor. To the department filtration or sedimentation. Rust is preferably separated magnetically. The invention can be used to purify 2-isopropylamino-4-ethylamino-6-chloro-s-triazine, whose softening reduces its quality. 2- -isopropylamino-4-ethylamino-6-chloro-s- -triazine is used as a herbicide in agriculture najma in corn crops.

Description

The invention relates to the purification of 2-isopropylamino-4-ethylamino-6-chloro-s-triazine contaminated with organic and inorganic substances.

Among the best known and most widely produced s-triazine herbicides are 2-isopropylamino-4-ethylamino-6-chloro-s-triazine (atrazine). Herbicidine effects were discovered in Switzerland in 1954 and are described in Swiss Patent 229 227. The preparation of atrazine by reaction of cyanuric chloride, ethylamine, isopropylamine and sodium hydroxide in aqueous chlorobenzene is described in U.S. Pat. pat. The preparation of atrazine by reacting cyanuric chloride with ethylamine, isopropylamine in an anhydrous organic solvent, using anhydrous ammonia to bind the resulting hydrogen chloride, is described in Swiss Patent 508,640. The product obtained contains 92% atrazine. The effect of pH on atrazine yield is described in the patents NDR and NSR. According to the GDR pat. 51,646, the best yield is obtained if in the first reaction stage, i.e. the reaction is carried out in the first step. j. after the addition of the first amine and the alkali metal hydroxide, the pH is maintained at 6 to 8, in the second reaction stage, i.e., the reaction is carried out at a pH of 6 to 8. j. after addition of the second amine and the alkali metal hydroxide, the pH is maintained at

8.5 to 9. The atrazine yield is 96%. German Patent 2,032,861 discloses a pH of 6.5-10 in the first stage. U.S. Pat. Nos. 3,328,399 and 3,586,679 describe a process for preparing atrazine from cyanuric chloride, ethylamine, isopropylamine in an anhydrous medium at a temperature of 120 to 170 ° C while distilling off the resulting hydrogen chloride. The advantage of the method is that the problem of waste water containing mineral salts is eliminated. Swiss Patent No. 546 247 describes an adiabatic process for producing atrazine in a water-insoluble solvent by reacting ethylamine, isopropylamine, alkali hydroxide with cyanuric chloride. In French. pat. 2,296,628, rum. pat. 60,016, jap. pat. 131 592 (1977), it is recommended that the first isopropylamine be metered in at amine dosing for atrazine production. Banks C. et al.,

J. Am. Chem. Soc. 66, 1771 (1944) and Friedheim, E., J. Am. Chem. Soc., 66, 1725 (1944), recommend a temperature of about 0 ° C for the first reaction stage of atrazine production and a temperature of 30 to 50 ° C for the second reaction stage. In the first reaction step, a mixture of water and ice is used as the reaction medium, optionally water, ice and an organic solvent.

References in the literature do not pay attention to the cleaning of heavy contaminated waste and atrazine produced during its production.

The above-mentioned drawbacks are eliminated by the method of purification of 2-isopropylamino-4-ethylamino-6-chloro-s-triazine, which consists in the fact that 2-isopropylamino-4-ethylamino-6-chloro-s-triazine is contaminated with organic or inorganic substances insoluble in organic solvents, dissolves and / or melts in organic water-insoluble solvents such as e.g. aliphatic, aromatic hydrocarbons, or derivatives thereof, preferably at the boiling point of the solvent, wherein the insoluble impurities are separated from the solution and / or emulsion of 2-isopropylamino-4-ethylamino-6-chloro-s-triazine in an organic solvent. The organic water-insoluble solvent is separated by distillation. Water distillation may be preferred. The impurities are preferably separated from the solution or emulsion by filtration, whereby a fine screen filtration can be used. Inorganic compounds can be separated by sedimentation. The impurities containing iron can be separated magnetically.

Purification of 2-isopropylamino-4-ethylamino-6-chloro-s-triazine can be made from a water-insoluble organic solvent in the presence of water.

According to the invention, the contaminated 2-isopropylamino-4-ethylamino-.epsilon.-chloro-s-triazine is purified and improved. The contamination must be caused by insoluble substances in organic water-insoluble solvents. The solubility of 2-isopropylamino-4-ethylamino-6-chloro-s-trlazine is strongly temperature-dependent in most solvents. At the boiling point of the solvent, a portion of the 2-isopropylamino-4-ethylamino-6-chloro-s-triazine melts and makes the mixture of substances opaque. Filtration through a fine sieve is sufficient to separate most of the impurities. Larger inorganic particles are separated by advantageous sedimentation, which can be done on a simple device. The fine iron-containing particles are preferably separated by a magnet. Since the solubility of 2-isopropylamino-4-ethylamino-6-chloro-s-triazine is greatest in the water-insoluble solvent at the boiling point of the mixture, at higher temperature the fine particles exhibit a significant Brownian motion, preventing them from sedimentation. In the case of ferromagnetic particles, this disadvantage is eliminated by means of a magnet. The cleaning can be carried out in the presence of water, using a wet material which does not need to be dried before cleaning.

Example 1

200 ml of technical chlorobenzene and 100 g of contaminated 2-isopropylamino-4-ethylamino-6-chloro-s-triazine containing 52.1 wt. technical 2-isopropylamino-4-ethylamino-6-chloro-s-triazine,

0.6 wt. % of polypropylene fibers from the filter) sheet, 0.4 wt. rust expressed as FeaOs and 0.9% sand. The flask was placed on an electromagnetic stirrer and heated to boiling point and passed through a 0.355 x 0.355 mm stainless steel screen. Fibers and larger inorganic232643 were collected on the screen

High impurities. Chlorobenzene was distilled off with water vapor. The obtained 2-isopropylamino-4-ethylamino-6-chloro-s-triazine after drying contained 0.13 wt. ash.

Example 2

The procedure of Example 1 was followed except that toluene was used as the solvent. The amount of 2-isopropylamino-4-ethylamino-6-chloro-s-triazine was 50 g. After passing through the sieve, the remaining ferromagnetic substances were removed with a magnet. The obtained 2-isopropylamino-4-ethylamino-6-chloro-s-triazine contained 0.11% w / w. ash.

Example 3

The procedure of Example 2 was followed except that the petroleum fraction having a hydrocarbon fraction boiling in the range of 50-80 ° C was used as solvent. The obtained 2-isopropylamino-4-ethylamino-6-chloro-s-triazine contained 0.14 percent ash.

Example 4

The procedure of Example 2 was followed except that nitrobenzene was used as the water-insoluble solvent. 2-Isopropylamino-4-ethylamino-6-chloro-s-triazine was obtained with a content of 0.22% by weight. ash.

Example 5

The procedure of Example 2 was followed except that the insoluble matter was collected by filtration on a heated funnel. The 2-isopropylamino-4-ethylamino-6-chloro-s-triazine obtained contained 0.02% ash.

Example 6

The procedure of Example 1 was followed except that 2-isopropylamino-4-ethylamino-6-chloro-s-triazine contaminated with sand was used. The sand was separated by sedimentation for 10 minutes after being passed into solution. The obtained 2-isopropylamino-4-ethylamino-6-chloro-s-triazine contained 0.35 wt. ash.

According to the process of the present invention, 2-isopropylamino-4-ethylamino-6-chloro-s-triazine is recovered to form a fully-fledged raw material which can be further processed into herbicidal preparations. Up to now, the contaminated 2-isopropylamino-4-ethylamino-6-chloro-s-triazine has not been cleaned and has been taken to a landfill as waste. Regeneration is simple, low on equipment and raw materials, and can be easily incorporated into the production process of 2-isopropylamino-4-ethylamino-6-chloro-s-triazine.

Claims (5)

232643 Dirt impurities. The chlorobenzene was distilled off with aqueous steam. The 2-isopropylamino-4-ethylamino-6-chloro-s-triazine obtained after drying contained 0.13 wt. ash. Example 2 Example 1 was followed with the difference that toluene was used as solvent. The amount of 2-isopropylamino-4-ethylamino-6-chloro-s-triazine was 50 g. After sieving, the remaining ferromagnetic materials were removed with a magnet. The 2-isopropylamino-4-ethylamino-6-chloro-s-triazine obtained contained 0.11% by weight. ash. EXAMPLE 3 The procedure of Example 2 was followed except that the gasoline with a hydrocarbon fraction of 50 DEG to 80 DEG C. was used as solvent. The 2-isopropylamino-4-ethylamino-6-chloro-s-triazine obtained contained 0.14 percent ash. EXAMPLE 4 The procedure of Example 2 was followed except that nitrobenzene was used as the water-soluble solvent. 2-Isopropyl-4-ethylamino-6-chloro-s-triazine was obtained with a content of 0.22% by weight. ash. EXAMPLE 5 The procedure of Example 2 was followed except that insoluble matter was collected by filtration on a heated funnel. The 2-isopropylamino-4-ethylamino-6-chloro-s-triazine obtained contained 0.02% ash. EXAMPLE 6 Example 1 was followed with the difference that sand-treated technical 2-isopropylamino-4-ethylamino-6-chloro-s-triazine was used. The sand was separated into the solution by sedimentation for 10 minutes. The 2-isopropylamino-4-ethylamino-6-chloro-s-triazine obtained contained 0.35% by weight. po-pola. According to the present invention, 2-isopropylamino-4-ethylamino-6-chloro-s-triazine is regenerated into a full-value raw material which is further processed to herbicidal formulations. So far, 2-isopropylamino-4-ethylamino-6-chloro-s is contaminated. -triazine did not purify and waste to the waste dump. The regeneration is a simple, low-cost equipment and raw material and can be very easily integrated into the production process of 2-iso-propylamino-4-ethylamino-6-chloro-s-triazine. OBJECT A method for purifying 2-isopropylamino-4-ethylamino-6-chloro-s-triazine with contaminated organic or inorganic substances such as sand, rust, characterized in that the impure 2-isopropylamino-4-ethylamino-6- the chloro-s-triazine is dissolved and / or melted with a water-soluble organic solvent, preferably at the boiling point of the mixture, whereby the insoluble impurities are separated and the solvent is distilled off from 2-isopropylamino-4-ethylamino-6- with chloro-s-triazine-aqueous. VYNALEZU 2. Process according to claim 1, characterized in that the impurities are separated by filtration. 3. Process according to claim 1, characterized in that the inorganic impurities are separated by sedimentation. Method according to claim 1, characterized in that the rust is separated magnetically or electromagnetically. 5. A method as claimed in any one of claims 1 to 4. that cleaning takes place in the presence of water.