Synthesis method of bromine monochloride

Abstract

The invention provides a synthesis method of bromine monochloride, which comprises the following steps: dissolving bromide containing metal ions in an organic solvent, introducing chlorine, reacting to generate bromine monochloride and metal-containing chloride, filtering, and distilling to obtain pure bromine monochloride. According to the method, the polar organic solvent is selected as the solvent, the generation of bromine trichloride can be effectively inhibited at proper reaction temperature and time, and bromine monochloride with relatively high purity is obtained; according to the invention, the problems of complex preparation and low purity of bromine monochloride are effectively solved.

Description

Technical Field

[0001] The invention belongs to the field of halogen intercompounds, and specifically relates to a new method for synthesizing bromine monochloride by using metal bromide salt as raw material. Background Art

[0002] Bromine chloride is an inorganic compound with the chemical formula BrCl. Bromine chloride is an important chemical widely used in pharmaceuticals, pesticides, dyes, optoelectronic materials and other fields, mainly as an industrial disinfectant. In addition, bromine chloride plays an important role in organic chemical reactions, especially as a halogenating agent, participating in addition and substitution reactions of organic matter. These reactions are very critical steps in organic synthesis because they can change the molecular structure to generate new compounds with different physical and chemical properties, which are then used in various industrial and medical fields.

[0003] Chinese patent CN101264864A discloses a self-pressurized one-step bromine chloride synthesis technology, wherein liquid bromine after drying pretreatment and high-purity chlorine after decompression are subjected to synthesis reaction in a closed medium-pressure reactor, and the chlorine introduction rate is 0.35-0.60 g / min. With the introduction of chlorine and the progress of the chlorine-bromine synthesis reaction, the pressure in the reactor increases and the temperature rises, and the pressure can reach 10 atm and the temperature can reach 70°C. When the ratio of the mole number of chlorine to the mole number of bromine in the medium-pressure reactor reaches 1.00-1.02:1, the introduction of chlorine into the medium-pressure reactor is stopped. After the chlorine is stopped, the materials in the reactor are kept stirred for 15-20 minutes to obtain a high-purity bromine chloride product.

[0004] Chinese patent CN1554571A relates to a bromine chloride synthesis technology, which is to synthesize bromine chloride in a reactor at a low temperature of -10 to -20°C after liquid bromine and chlorine gas are dried and pretreated. The raw material liquid bromine and chlorine gas are pretreated to reduce the occurrence of side reactions.

[0005] The two bromine chloride preparation technologies react bromine and chlorine gas to produce bromine chloride of low purity and easily generate related derivatives, such as bromine trichloride, which is not convenient for subsequent bromine chloride applications. The reaction temperature of the process of Chinese patent CN101264864A is also high, which is dangerous during production. Summary of the invention

[0006] The invention provides a method for synthesizing bromine monochloride to solve the technical problem that the bromine chloride prepared by the reaction of bromine element and chlorine gas has low purity and is very easy to generate related derivatives.

[0007] The technical solution adopted by the present invention is:

[0008] A method for synthesizing bromine monochloride comprises dissolving a bromide containing metal ions in an organic solvent, introducing chlorine gas to react to generate bromine monochloride and the metal chloride, filtering and distilling to obtain pure bromine monochloride.

[0009] Preferably, the method specifically comprises the following steps:

[0010] Step 1, adding bromide of metal ions into an organic solvent to form a mixed solution;

[0011] Step 2, cooling the mixed solution to react, and stirring the mixed solution during the cooling process;

[0012] Step 3, continuously passing chlorine gas into the mixed solution;

[0013] Step 4, filtering the mixed solution after the chlorine gas is introduced;

[0014] Step 5, distill the filtered mixed solution under reduced pressure, and the residue after the distillation under reduced pressure is bromine monochloride.

[0015] Preferably, the bromide of the metal ion in step 1 is magnesium bromide, sodium bromide, zinc bromide, barium bromide, potassium bromide, iron bromide, copper bromide or calcium bromide.

[0016] Preferably, the organic solvent in step 1 is a polar solvent.

[0017] Preferably, the polar solvent includes methanol, ethanol, acetonitrile, DMF, dioxane, chloroform or dichloromethane.

[0018] Preferably, the polar solvent is chloroform.

[0019] Preferably, in step 1, the mass ratio of the bromide of the metal ion to the organic solvent is 10-100:100-400.

[0020] Preferably, the temperature of the cooling reaction in step 2 is 0 to 30°C.

[0021] Preferably, in step 3, chlorine gas is continuously introduced into the mixed solution for 60 to 240 minutes at a temperature of 0 to 30°C.

[0022] Preferably, the vacuum distillation pressure is -0.090 to -0.095 MPa, and the vacuum distillation temperature is room temperature, 10 to 30°C.

[0023] The beneficial effects obtained by the present invention are:

[0024] 1. The present invention directly obtains bromine monochloride by passing chlorine gas into metal bromide;

[0025] 2. The preparation steps of bromine monochloride are effectively simplified, saving costs; and the added solvent chloroform can easily obtain high-purity bromine monochloride;

[0026] 3. Organic solvents and appropriate temperature can effectively solve the generation of bromine trichloride and improve product yield;

[0027] 4. The reaction temperature is room temperature and the process is relatively safe. DETAILED DESCRIPTION

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the embodiments are briefly introduced below. Obviously, the following description only describes some embodiments of the present invention.

[0029] Example 1

[0030] A method for synthesizing bromine monochloride comprises the following steps:

[0031] Step 1, take 200g of chloroform and 20g of zinc bromide, put the chloroform into a reaction bottle, and add the zinc bromide into the chloroform;

[0032] Step 2, place the reaction bottle in a condensation pump with stirring, adjust the temperature to 10°C, and turn on stirring;

[0033] Step 3, continuously introduce chlorine gas into the reaction flask for 120 min;

[0034] Step 4, filtering the mixed solution in the reaction bottle;

[0035] Step 5, distill the filtered liquid under reduced pressure, set the pressure to -0.090 MPa, take the solid obtained at the bottom of the bottle, the purity of bromine chloride is 97.1%, and the yield is 96.7%.

[0036] Example 2

[0037] A method for synthesizing bromine monochloride comprises the following steps:

[0038] Step 1, take 400g acetonitrile and 100g sodium bromide, put the acetonitrile into a reaction bottle, and add zinc bromide into chloroform;

[0039] Step 2, place the reaction bottle in a condensation pump with stirring, adjust the temperature to 30°C, and turn on stirring;

[0040] Step 3, continuously introduce chlorine gas into the reaction flask for 240 min;

[0041] Step 4, filtering the mixed solution in the reaction bottle;

[0042] Step 5, subjecting the filtered liquid to vacuum distillation, setting the pressure to -0.090 MPa, and taking the solid obtained at the bottom of the bottle, i.e., bromine chloride, with a purity of 93.1% and a yield of 92.6%.

[0043] Example 3

[0044] A method for synthesizing bromine monochloride comprises the following steps:

[0045] Step 1, take 100g DMF and 10g zinc bromide, put DMF into a reaction bottle, and add zinc bromide into chloroform;

[0046] Step 2, place the reaction bottle in a condensation pump with stirring, adjust the temperature to 0°C, and turn on stirring;

[0047] Step 3, continuously introduce chlorine gas into the reaction flask for 60 min;

[0048] Step 4, filtering the mixed solution in the reaction bottle;

[0049] Step 5, subjecting the filtered liquid to vacuum distillation, setting the pressure to -0.095 MPa, and taking the solid obtained at the bottom of the bottle, i.e., bromine chloride, with a purity of 94.3% and a yield of 93.8%.

[0050] Example 4

[0051] A method for synthesizing bromine monochloride comprises the following steps:

[0052] Step 1, take 200g acetonitrile and 20g zinc bromide, put the acetonitrile into a reaction bottle, and add the zinc bromide into the acetonitrile;

[0053] Step 2, place the reaction bottle in a condensation pump with stirring, adjust the temperature to 10°C, and turn on stirring;

[0054] Step 3, continuously introduce chlorine gas into the reaction flask for 120 min;

[0055] Step 4, filtering the mixed solution in the reaction bottle;

[0056] Step 5, subjecting the filtered liquid to vacuum distillation, setting the pressure to -0.090 MPa, taking the solid obtained at the bottom of the bottle, the purity of bromine chloride is 91.1%, and the yield is 95.8%.

[0057] Comparative Example 1

[0058] The difference between this comparative example and the embodiment is that in step 2, the reaction flask is stirred and is not placed in a condensation pump; the other steps are the same as those in embodiment 1.

[0059] A method for synthesizing bromine monochloride comprises the following steps:

[0060] Step 1, take 200g of chloroform and 20g of zinc bromide, put the chloroform into a reaction bottle, and add the zinc bromide into the chloroform;

[0061] Step 2: Turn on stirring and stir at 38°C;

[0062] Step 3, continuously introduce chlorine gas into the reaction flask for 120 min;

[0063] Step 4, filtering the mixed solution in the reaction bottle;

[0064] Step 5, distill the filtered liquid under reduced pressure, set the pressure to -0.090 MPa, take the solid obtained at the bottom of the bottle, the purity of bromine chloride is 51.4%, the yield is 50.6%, and the reaction is incomplete.

[0065] Comparative Example 2

[0066] The difference between this comparative example and the embodiment is that: in step 3, the time for continuously introducing chlorine gas is 20 minutes; the other steps are the same as those in embodiment 1.

[0067] A method for synthesizing bromine monochloride comprises the following steps:

[0068] Step 1, take 200g of chloroform and 20g of zinc bromide, put the chloroform into a reaction bottle, and add the zinc bromide into the chloroform;

[0069] Step 2, place the reaction bottle in a condensation pump with stirring, adjust the temperature to 10°C, and turn on stirring;

[0070] Step 3, continuously introduce chlorine gas into the reaction flask for 20 min;

[0071] Step 4, filtering the mixed solution in the reaction bottle;

[0072] Step 5, the filtered liquid is subjected to reduced pressure distillation, the pressure is set to -0.090 MPa, the purity of bromine chloride is 11.4%, the yield is 10.3%, and the reaction is incomplete.

[0073] Comparative Example 3

[0074] A method for synthesizing bromine monochloride comprises the following steps:

[0075] Step 1, take 200g of chloroform and 20g of zinc bromide, put the chloroform into a reaction bottle, and add the zinc bromide into the chloroform;

[0076] Step 2, place the reaction bottle in a pump with stirring, adjust the temperature to 60°C, and turn on stirring;

[0077] Step 3, continuously introduce chlorine gas into the reaction flask for 120 min;

[0078] Step 4, filtering the mixed solution in the reaction bottle;

[0079] Step 5, the filtered liquid is subjected to reduced pressure distillation, the pressure is set to -0.090 MPa, the purity of bromine chloride is 45.3%, the yield is 25.7%, and the reaction is incomplete.

[0080] Comparative Example 4

[0081] A method for synthesizing bromine monochloride comprises the following steps:

[0082] Step 1, take 200g of chloroform and 20g of zinc bromide, put the chloroform into a reaction bottle, and add the zinc bromide into the chloroform;

[0083] Step 2, place the reaction bottle in a condensation pump with stirring, adjust the temperature to 10°C, and turn on stirring;

[0084] Step 3, continuously introduce chlorine gas into the reaction flask for 120 min;

[0085] Step 4, filtering the mixed solution in the reaction bottle;

[0086] Step 5, distilling the filtered liquid under reduced pressure, setting the pressure to normal pressure, the purity of bromine chloride is 68.3%, the yield is 66.8%, and the reaction is incomplete.

[0087] Through experiments, it can be seen that relatively pure bromine monochloride can be obtained through the present invention with a high yield.

[0088] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for synthesizing bromine monochloride, characterized in that: The bromide containing metal ions is dissolved in an organic solvent, and chlorine gas is introduced to react to generate bromine monochloride and metal chloride. After filtering and distillation, pure bromine monochloride is obtained.

2. A method for synthesizing bromine monochloride according to claim 1, characterized in that: The specific steps include: Step 1, adding a bromide containing metal ions into an organic solvent to form a mixed solution; Step 2, cooling the mixed solution to react, and stirring the mixed solution during the cooling process; Step 3, continuously passing chlorine gas into the mixed solution; Step 4, filtering the mixed solution after the chlorine gas is introduced; Step 5: distill the filtered mixed solution under reduced pressure, and the residue left after the distillation under reduced pressure is bromine monochloride.

3. A method for synthesizing bromine monochloride according to claim 2, characterized in that: The bromide containing metal ions in step 1 is magnesium bromide, sodium bromide, zinc bromide, barium bromide, potassium bromide, iron bromide, copper bromide or calcium bromide.

4. A method for synthesizing bromine monochloride according to claim 2, characterized in that: The organic solvent in step 1 is a polar solvent.

5. A method for synthesizing bromine monochloride according to claim 4, characterized in that: The polar solvent includes methanol, ethanol, acetonitrile, DMF, dioxane, chloroform or dichloromethane.

6. A method for synthesizing bromine monochloride according to claim 5, characterized in that: The polar solvent is chloroform.

7. A method for synthesizing bromine monochloride according to claim 2, characterized in that: In step 1, the mass ratio of the bromide containing metal ions to the organic solvent is 10-100:100-400.

8. A method for synthesizing bromine monochloride according to claim 2, characterized in that: The temperature of the cooling reaction in step 2 is 0~30℃.

9. A method for synthesizing bromine monochloride according to claim 2, characterized in that: In step 3, chlorine gas is continuously introduced into the mixed solution for 60 to 240 minutes at a temperature of 0 to 30°C.

10. A method for synthesizing bromine monochloride according to claim 2, characterized in that: The pressure of the vacuum distillation is -0.090~-0.095MPa, and the temperature of the vacuum distillation is room temperature.