Water-alkali dehydrochlorination catalyst preparation method

 

The invention relates to organic synthesis, in particular, to a method for producing the catalyst for aqueous-alkaline dehydrochlorination of peliharakan.

It is known that catalysts for aqueous-alkaline dehydrochlorination of peliharakan are Quaternary ammonium salts (H) (Demlow E. interfacial catalysis. M. The World. 1987).

Closest to the claimed technical essence and the achieved effect is a method of obtaining catalysts for aqueous-alkaline dehydrochlorination of peliharakan consisting of Quaternary ammonium salts and alcohol additives. The Quaternary ammonium salt is obtained from the clarified waste of allylchloride with the content of 30-50% of the mass. 1,3-dichloropropanol, 30-60% of the mass. 1,2-dichloropropane, 3-5% of the mass. 1,2,3-trichlorpropane initial treatment with dimethylamine, diethylamine at a temperature of 50-55°or diethanolamine at a temperature of 90-100°when the molar ratio of 1,3-dichlorophen: amine = 1:(1-1,1), with the further treatment of the reaction mixture stoichiometric quantity to receive tertiary amines water 25-35% NaOH solution, separation of the organic phase and adding to it the stoichiometric quantity to the source of 1,3-dichloropropene allyl chloride, maintaining the reaction mass under stirring at a temperature of 45°With subsequent dissolution of the image is wasasa Quaternary ammonium salt the minimum quantity of demineralized water, separation of the organic phase to obtain 50-60%aqueous solution of Quaternary ammonium salt and adding thereto an alcohol additive ROH, where R is alkyl With₃-C₄, l=CH-CH₂HE and the selection of the organic phase 1,2-dichloropropane /EN 2174441/.

Model reaction to study the catalytic activity of the system H: alcohol served aqueous-alkaline dehydrochlorination of 1,2-dichloroethane, the most resistant to reaction β-elimination.

The reaction is carried out at a temperature of 50-55°With the action of aqueous NaOH in the presence of 1% (wt) to the dichloroethane HOUR. The reaction proceeds with a speed of 32 mol/PS 10⁴and 34.6 mol/PS 10⁴accordingly, when applying the above-mentioned Quaternary ammonium salts.

The disadvantage of the above HOURS are:

- application for obtaining hard-to-reach diethylamine and diethanolamine.

- application to obtain the Quaternary ammonium salts of energy-intensive and technologically complex allylchloride.

The task of the claimed invention to provide an effective, readily available catalyst for aqueous-alkaline dehydrochlorination of peliharakan by recycling waste allyl chloride.

As is known, upon receipt allyl chloride is formed to 280 kg of waste per ton of the target product. The clarified waste this output is VA contain 30-50% of 1,3-dichloropropanol, 30-60% 1,2-dichloropropane, 3-5% 1,2,3-trichloropropane (Oshin L.A. Industrial organochlorine products. M. Chemistry. 1978 s).

The use of the claimed invention can be obtained by technical result:

- disposal of waste chloride allyl;

- getting cheap and highly effective catalyst for the reaction of aqueous-alkaline dehydrochlorination of peliharakan;

- the exception to the technology of the preparation of the catalyst difficult diethanolamine, diethylamine;

a significant simplification of the technological process of obtaining an effective catalyst for aqueous-alkaline dehydrochlorination of peliharakan.

This technical result in the implementation of the invention is achieved in that the clarified waste production allylchloride with the content of 30-50% (by weight) of 1,3-dichloropropanol, 30-60% (by weight) 1,2-dichloropropane, 3-5% (wt) 1,2,3-trichlorpropane initially under stirring at a temperature of 5-10°treated With equimolar amount of amine taken in the form of 30-60%aqueous solution, and after keeping the mixture for 0.5-1 hour at the same temperature is treated with a stoichiometric amount of NaOH to dimethylamine, taken in the form of 40-44%aqueous solution.

After keeping the mixture at a temperature of 20-25°within 0.5 to 1 hour is added an equimolar amount is in the dimethylamine 1,3-dichloropropanol, contained in the clarified waste production allylchloride. Then this mixture is heated to 60-70°With stirring for 2-3 hours and sent to patristical.

The organic phase containing mainly 1,2-dichloropropane and 1,2,3-trichloropropane separated and the inorganic phase consisting of an aqueous solution of Quaternary ammonium salt of the formula [(CH₃)₂N(CH₂CH=l

+

2

]CL^-and the appropriate amount of NaCl is directed to create a catalytic system with the addition of alcohol additives ROH, where R=C₁-C₄, benzyl. As alcohol additives used methanol, ethanol, butanol, and benzyl alcohol in a molar ratio to the Quaternary amine of 1:1-3.

The method is as follows.

In a reactor equipped with a stirrer, thermometer, reflux condenser and a thermostatic device put the estimated number of dimethylamine, taken in the form of 30-60%aqueous solution. Under stirring at a temperature of 5-10°add the estimated amount of the clarified waste of allylchloride containing 30-50% 1,3-dichloropropene, 30-60% of the mass. 1,2-dichloropropane, 3-5% of the mass. 1,2,3-trichlorpropane. The mixture was kept of 0.5-1.0 h after h the th to the reaction mass is added the calculated amount of NaOH in the form of 40-44%aqueous solution at a temperature of 5-10° To maintain the mixture at 20-25°C for 0.1 to 1.0 h and then the reaction mass is added the calculated amount (equimolar amount to the dimethylamine) 1,3-dichloropropene contained in the clarified waste production allylchloride, stand the mixture for 2-3 h at 60-70°with stirring, the organic phase is separated and added alcohol additive ROH in a molar ratio to the Quaternary amine 1:1-3, where R is C1-C4, or benzyl.

The conversion of 1,3-dichloropropanol quantitative approaches (98-99,5%).

The method is illustrated by the following example:

Example No. 1. In a reactor equipped with a stirrer, thermometer, reflux condenser and a thermostatic device, placed 44 g of dimethylamine taken in the form of a 50%aqueous solution. Under stirring at a temperature of 5-10°add 222 g of clarified waste allyl chloride, containing 49% (mass) of the mixture of TRANS-, CIS-1,3-dichloropropene, 48% 1,2-dichloropropane and 3% 1,2,3-trichlorpropane.

After keeping the mixture for 1 hour to the reaction mixture add 39,1 g of NaOH is taken in the form of a 44%aqueous solution.

The mixture is stirred for 1 hour at a temperature of 20-25°With, then add another 222 g of clarified waste allyl chloride of the same composition and the mixture is stirred at a temperature of 70°C for 3 hours. After cooling to reaction the th mass add water to dissolve the precipitated NaCl and poured into a separating funnel.

The organic layer is separated and the inorganic layer consisting of water, NaCl, and Quaternary ammonium salts of the formula [(l=CH-CH₂)₂-N(CH₃)₂]⁺CL^-used for catalytic systems the addition to the inorganic phase of the alcohol ROH, where R=C₁-C₄, benzyl when the molar ratio of H: alcohol of 1:1-3.

Get 560 g of 50%aqueous salt solution of the above HOURS.

The dehydrochlorination of 1,2-dichloroethane.

In chetyrehosnuju flask equipped with a stirrer, reflux condenser, thermometer and thermostatic device, put 98 g of 1,2-dichloroethane and 1% of the mass. it dichloroethane obtained HOURS, where previously added molar number to an HOUR butyl alcohol. At a temperature of 50-55°With stirring over a separating funnel, add 80 g of NaOH in 30%aqueous solution. Eye-catching vinyl chloride through a reflux trap cooled with nitrogen trap. The reaction time is 30 minutes, the rate of formation of vinyl chloride 32.1 mol/l··10⁴.

Example No. 2. In the conditions of example No. 1 to the catalyst added benzyl alcohol (molar ratio of H: alcohol = 1:1).

The rate of formation of vinyl chloride was 36.4 mol/l··10⁴.

Example No. 3. In the conditions of example No. 1 to the catalyst added ethyl JV the RT at a molar ratio of H: alcohol 1:3. The rate of formation of vinyl chloride amounted to 30.5 mol/l··10⁴.

1. The method of producing catalysts for aqueous-alkaline dehydrochlorination the interaction of the aqueous secondary amines and clarified waste of allylchloride containing 30 to 50 wt.% 1,3-dichloropropanol, 30-60 wt.% 1,2-dichloropropane, 3-5 wt.% 1,2,3-trichlorpropane and alcohol additives, characterized in that 30-60%aqueous solution of dimethylamine at a temperature of 5-10°add the clarified waste from the production of allyl chloride in equimolar amounts to 1,3 dimethylamine-dichloropropanol contained in the waste, maintain the mixture for 0.5-1.0 hours, was added to the reaction mass stoichiometric quantity to dimethylamine NaOH, taken in the form of 40-44%aqueous solution, incubated the mixture at 20-25°C for 0.1 to 1.0 h, add the clarified waste from the production of allyl chloride in equimolar the number to the dimethylamine 1,3-dichloropropanol, maintain the mixture at 60-70°With stirring for 2-3 h, the organic phase is separated and added to the inorganic phase of the alcohol additive ROH in a molar ratio to the Quaternary amine 1:1-3, where R is a C₁-C₄or benzyl.

2. The method according to claim 1, characterized in that as the alcohol additives used methanol, ethanol, butanol, benzyl alcohol.