RU2191174C2 - Method of yperite destruction - Google Patents

Abstract

FIELD: poisoning substances, chemical technology. SUBSTANCE: invention relates to a method of destruction of yperite that is a poisoning substance of the vesicatory effect. Method is performed by carrying out a reaction of yperite dehydrochlorination using a composite mixture comprising an alkaline metal hydroxide an aqueous solution, N,N,N-tributyl-N- -benzylammonium chloride as a catalyst of an interphase transfer, benzyl alcohol as a co-catalyst and dimethylsulfoxide as a solvent. Method ensures to destruct yperite at temperature 30-40 C to a residual yperite concentration 0.01 mg x ml^-1, not above in combination with decrease amount of technological waste and increased rate of detoxification. EFFECT: improved method of destruction. 2 tbl, 2 ex

Description

 The invention relates to the destruction of chemical warfare agents (S), in particular to the destruction of a poisonous substance of a skin-boiling effect of mustard gas.

 Currently existing methods for the destruction of mustard gas (β, β′-dichlorodiethyl sulfide) - burning, oxidation, oxidative chlorination, as well as methods adopted for use at storage facilities, are not without drawbacks. These include, first of all, a large amount of waste, low technology (the formation of hardly transported reaction masses during degassing with aqueous suspensions of calcium hypochlorite and hydrogen peroxide), the danger of environmental pollution during combustion, and high energy intensity. (Soborovsky LZ, Epshtein G.Yu. Chemistry and technology of military chemicals. - M.: State. Publishing House of the defense industry, 1938, p. 587; Franke Z., Franke E. Chemistry of toxic substances. - M. : Chemistry, vol. 1, 1973, p. 440).

Technologically justified and economically affordable methods for the destruction of OM should include those that use reactions catalyzed by bases (alkali metal hydroxides). They are used for the degassing of sarin, soman, lewisite, phosgene and mustard gas. However, the destruction of mustard gas based on alkaline hydrolysis is limited due to the impossibility of creating homogeneous reaction masses on its basis (the solubility of mustard gas in water at 25 ^o C is 0.7 g / l) and the duration of the process.

 The use of the dehydrochlorination reaction of organochlorine compounds in the presence of phase transfer catalysts opens up certain prospects. (Interfacial catalysis. Chemistry, catalysts and application. / Under the editorship of Starks Ch.M. - M .: Chemistry, 1991, p.160; Demlov E., Demlov Z. Interfacial catalysis. - M .: Mir, 1987, p. . 485).

 Currently known composition for the destruction of sending substances using a composite mixture, which includes a phase transfer catalyst - N, N, N, N-tetraalkylammonium hydroxide, solutions of alkali metal alkoxides in a mixture of dimethyl sulfoxide (DMSO) with water. However, in this work, the composition of the catalytic system for the destruction of OBs was not optimized. (US 3810842, 05/14/1974).

Known methods for the destruction of mustard gas by treatment with an aqueous solution of alkali in a hydrophilic solvent, for example DMSO, at a temperature of 85-110 ^o C or by ultrasonic treatment (RU 2139855 C1, 10.20.1999, RU 2139856 C1, 20.10.1999). The disadvantages of the proposed methods for the destruction of mustard gas include the need to maintain a high temperature, as well as the use of special technological equipment (ultrasonic bath) to increase the rate of decomposition of mustard gas.

According to the set of features, the closest to the proposed method for the destruction of mustard gas is the method for the destruction of mustard gas (or its solution in hexane) in a fluidized bed with an aqueous alkali solution in the presence of an interfacial transfer catalyst at a temperature of 20-60 ^o C. As a catalyst, quaternary ammonium salts are used, for example N, N, N, N-tetrabutylammonium chlorides or N, N, N-tributyl-N-benzylammonium chlorides (RU 2041206 C1, 08/09/1995). The disadvantages of the proposed method for the destruction of mustard gas include the need to use combustible hexane, as well as to obtain a fluidized bed of special technological equipment - vibration mixers. This method is adopted as a prototype.

 The aim of the invention is to develop a method for the destruction of mustard gas using a catalytic system that allows under mild conditions without the use of special technological equipment to effectively destroy mustard gas.

 This goal is achieved by processing mustard gas, dissolved in DMSO, with aqueous solutions of alkalis under interfacial catalysis using a catalyst - TBBAH and cocatalyst - benzyl alcohol.

 It is known from the literature that the use of benzyl alcohol as a cocatalyst in the presence of a phase transfer catalyst of N, N, N-tributyl-N-benzylammonium chloride (TBBAH) leads to the formation of benzyloxy anions, which are most basic and capable of increasing the rate of dehydrochlorination of chloroalkanes. (Tolstikov G.A., Shavanov S.S. Interphase catalysis in the synthesis of organochlorine compounds, some aspects of the mechanism and industrial application. Kinetics and catalysis, 1996, v. 37, 5, p. 686-691).

 The proposed method for the destruction of mustard gas is based on the chemical process of dehydrochlorination of mustard gas, which is carried out in a medium containing two immiscible liquids: an aqueous solution of potassium hydroxide (sodium) and a solution of mustard gas in DMSO. In order to accelerate the progression of the decomposition of mustard gas, a phase transfer catalyst and a cocatalyst are added to the reaction mixture. Under these conditions, the main reaction is dehydrochlorination, rather than substitution, characteristic of mustard gas during hydrolysis with aqueous solutions of alkalis. (Alexandrov V.N., Emelyanov V.N. Poisoning substances. - M.: Military Publishing House, 1990, p. 271).

The dependences of the completeness of the degassing of mustard gas on the amount of the added catalyst — ammonium salts, the cocatalyst — benzyl alcohol, and the mustard: alkali ratio in fixed concentrations were studied. A solution containing 10.0 mustard gas in DMSO was mixed with a 40% aqueous solution of potassium or sodium hydroxide, providing a ratio (molar) mustard: alkali of 1: 2.1; 1: 2.3; 1: 2.5; 1: 3 and 1: 4 respectively. The catalyst is TBBAH or N, N-dimethyl-N-alkyl-N-benzylammonium chloride, where alkyl (C ₈ -C ₁₈ ) was added in an amount providing a ratio (molar) mustard: catalyst of 1: 0.1; 1: 0.2 and 1: 0.3, respectively. Socialization - benzyl alcohol was added in an amount that ensured the ratio (molar) of mustard: socialization 1: 0.1; 1: 0.2; 1: 0.3, respectively. The process was carried out with stirring of the reaction mass in the temperature range 30-50 ^o C. The research results are presented in table. 1.

 It has been established that with a mustard: alkali: catalyst: cocatalyst ratio of 1: 2.3: 0.1: 0.1: 0.1, respectively (TBBAH catalyst), mustard gas is destroyed by more than 99.99% within 25-30 minutes .

The use of N, N-dimethyl-N-alkyl-N-benzylammonium chloride as a catalyst, where alkyl (C ₈ -C ₁₈ ), does not lead to a deterioration in the reaction rates.

 The degassing of mustard gas is somewhat slowed down when using a 40% aqueous solution of sodium hydroxide. In this case, the reaction proceeds in 45-55 minutes.

The degassing process using this method is carried out to a content of mustard gas in the reaction mass of not more than 0.01 mg • ml ^-1 . Toxicological evaluation of the reaction masses on white mice with cutaneous application indicates that they belong to substances of the toxicity class III.

 The proposed method for the destruction of mustard gas can be used on an industrial scale, since it is based on the use of available domestic raw materials and allows the use of standard technological equipment of chemical plants without significant changes. The process does not require significant energy costs.

 Information confirming the feasibility of the method for the destruction of mustard gas in DMSO solutions by alkaline treatment in the presence of a phase transfer catalyst and cocatalyst are presented below.

Typical experience. In a reactor equipped with a reflux condenser, a sampler, and a mechanical stirrer, 10.0 (63 mmol) of mustard gas in 10.0 g (128 mmol) of DMSO, phase transfer catalyst, cocatalyst, and the calculated amount of 40% aqueous alkali are loaded. Stirred at 30-50 ^o C. At predetermined intervals of time samples of the organic phase of 0.1 ml are taken and analyzed for residual mustard content (see table. 1).

Example 1. Under the conditions of a typical experiment, a 40% aqueous solution of potassium hydroxide (8.1 g, 144 mmol of KOH in 12.1 ml of 672 mmol of water) is treated with 10.0 g (63 mmol) of mustard gas in 5.0 g (64 mmol) DMSO, 0.19 g (0.63 mmol) TBBAH, 0.07 g (0.63 mmol) of benzyl alcohol with stirring, at 30-50 ^o C. After heating the reaction mass for 30 min, a sample is taken, determined residual mustard content equal to 0.01 mg • ml ^-1 .

Example 2. Under the conditions of a typical experiment, a 40% aqueous solution of sodium hydroxide (8.1 g, 202 mmol of NaOH in 12.1 ml of 672 mmol of water) is treated with 10.0 g (63 mmol) of mustard gas in 5.0 g (64 mmol) DMSO, 0.23 g (0.63 mmol) N, N-dimethyl-N-alkyl-N-benzylammonium chloride, where alkyl (C ₈ -C ₁₈ ), 0.07 g (0.63 mmol) of benzyl alcohol with stirring, at 30-50 ^o C. After heating the reaction mass for 30 minutes, a sample is taken, the residual content of mustard gas equal to 0.01 mg • ml ^{-1 is} determined.

The reaction progress of the studied solutions was monitored by residual mustard gas concentrations using an HP 5890 Series II gas-liquid chromatograph (Hewlett Packard, United States) equipped with a flame ionization detector. The mixture was separated on an HP-1 quartz capillary column, 25 m long, 0.32 mm inner diameter, and a fixed liquid phase thickness of 0.17 μm. Operating mode: injector temperature 280 ^o С, detector temperature 280 ^o С, t _(column) = 50 ^o С, temperature rise 10 ^o С • min ^-1 - 270 ^o С. Carrier gas - helium, inlet pressure 1 atm, coefficient discharge 1 • 10 ^-1 , the volume of the injected sample 1 μl. The carrier gas is nitrogen, the feed rate is 2 ml • min ^-1 .

The composition and structure of the components of the reaction masses formed during the destruction of mustard gas were determined using a gas chromatography-mass spectrometric system: HP 5890 Series II gas-liquid chromatograph — HP 5972A mass-selective detector equipped with an HP-5 quartz capillary column, 60 m long, with an inner diameter of 0 , 32 mm, a thickness of the stationary liquid phase of 0.25 μm. Operating mode: injector temperature 280 ^o С, interface temperature 300 ^o С, initial column temperature 50 ^o С, temperature rise 10 ^o С • min ^-1 up to 300 ^o С with holding at the final temperature for 10 min. The carrier gas is helium, the inlet pressure is 1 atm, the discharge coefficient is 1 • 10 ^-1 , the volume of the injected sample is 1 μl. The ionization energy is 70 eV. The range of mass numbers is 35-450 amu Scan speed 1 scan • s ^-1 . To identify the components of the mixture, a Wiley 275 mass spectral database (275,000 compounds) was used.

 In the table. 2 presents the results of the analysis of the main products of mustard degassing in the conditions of the experiment.

Claims (1)

A method of destroying mustard gas by treating it with an aqueous solution of an alkali metal hydroxide in the presence of an organic solvent and an interphase transfer catalyst - quaternary ammonium chloride at an elevated temperature, characterized in that the process is carried out in the presence of a cocatalyst - benzyl alcohol and dimethyl sulfoxide is used as a solvent in a molar ratio of reactants alkali metal hydroxide: phase transfer catalyst: cocatalyst: solvent: mustard gas equal to 2.3: 0.1: 0.1: 1.0: 1.0 ootvetstvenno to a residual concentration of mustard not more than 0.01 mg • ml ^-1 for 30 min.

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