Method for producing dimethyl phosphite

Abstract

The invention discloses a method for producing dimethyl phosphite, and belongs to the field of fine chemical engineering. According to the method, methyl alcohol, phosphorus trichloride and ammonia are taken as raw materials, a methyl alcohol ejector, a phosphorus trichloride ejector, an esterification reaction kettle, a neutralizing tank, a rectifying tower and a dimethyl phosphite storage tank are taken as equipment, and the dimethyl phosphite is prepared by means of the procedures of esterification, neutralization, rectification and the like. The method for producing the dimethyl phosphite has the major advantages of adoption of general equipment, short production time, high product purity, high yield and realization of batch production. The dimethyl phosphite can be directly used for synthesizing an organic phosphorous insecticide in the field of pesticides, can be used for synthesizing other phosphorus-containing intermediates, is also used for producing an organic phosphoric acid corrosion inhibitor, a plastic aid, a dye additive and a fabric flame retardant, and can be taken as a lubricating oil additive, an adhesive and certain organic synthesis intermediates.

Description

technical field

[0001] The invention belongs to the field of fine chemicals, in particular to a production method of dimethyl phosphite. Background technique

[0002] Dimethyl phosphite, the molecular formula is C2H7O3P, the molecular weight is 110.05, the appearance is a colorless transparent liquid with a slight fragrance, the boiling point is 170°C, and the relative density is 1.20. It is soluble in water and easily soluble in most organic solvents such as alcohol and ether. The preparation method of dimethyl phosphite is obtained by the direct reaction of methanol and phosphorus trichloride. The specific methods include: solvent reaction and solvent-free reaction. The specific methods include vapor-liquid reaction, vapor-vapor reaction, discontinuous method, continuous method, etc. Because the reaction is a violent exothermic reaction, the reaction speed is fast, and it is completed in an instant. The discontinuous method has frequent operations, high labor intensity, lo...

Examples

Embodiment 1

[0013] Connect the methanol storage tank with the methanol injector, connect the phosphorus trichloride storage tank with the phosphorus trichloride injector, and connect with the esterification reactor, start the agitator of the esterification reactor to stir, methanol and trichloride At the same time, phosphorus is slowly sprayed into the esterification reactor in the form of mist. The molar ratio of the injected amount is methanol:phosphorus trichloride=3:1. The reaction is exothermic. The reaction temperature is controlled at 48°C by controlling the injected amount of methanol Between, after the reaction is completed, the solid in the esterification reactor is the crude dimethyl phosphite, and the gas is the by-product hydrogen chloride and methyl chloride, which are discharged and collected for other purposes, and the solid dimethyl phosphite crude into the neutralization tank. Because the crude product of dimethyl phosphite is acidic, add an appropriate amount of ammonia...

Embodiment 2

[0016] Connect the methanol storage tank with the methanol injector, connect the phosphorus trichloride storage tank with the phosphorus trichloride injector, and connect with the esterification reactor, start the agitator of the esterification reactor to stir, methanol and trichloride At the same time, phosphorus is slowly sprayed into the esterification reactor in the form of mist. The molar ratio of the injected amount is methanol:phosphorus trichloride=3:1. The reaction is exothermic. The reaction temperature is controlled at 50°C by controlling the injected amount of methanol Between, after the reaction is completed, the solid in the esterification reactor is the crude dimethyl phosphite, and the gas is the by-product hydrogen chloride and methyl chloride, which are discharged and collected for other purposes, and the solid dimethyl phosphite crude into the neutralization tank. Because the crude product of dimethyl phosphite is acidic, add an appropriate amount of ammonia...

Embodiment 3

[0018] Connect the methanol storage tank with the methanol injector, connect the phosphorus trichloride storage tank with the phosphorus trichloride injector, and connect with the esterification reactor, start the agitator of the esterification reactor to stir, methanol and trichloride At the same time, phosphorus is slowly sprayed into the esterification reactor in the form of mist. The molar ratio of the injected amount is methanol:phosphorus trichloride=3:1. The reaction is exothermic. The reaction temperature is controlled at 52°C by controlling the amount of methanol injected Between, after the reaction is completed, the solid in the esterification reactor is the crude dimethyl phosphite, and the gas is the by-product hydrogen chloride and methyl chloride, which are discharged and collected for other purposes, and the solid dimethyl phosphite crude into the neutralization tank. Because the crude product of dimethyl phosphite is acidic, add an appropriate amount of ammonia...

technical field

[0001] The invention belongs to the field of fine chemicals, in particular to a production method of dimethyl phosphite. Background technique

[0002] Dimethyl phosphite, the molecular formula is C2H7O3P, the molecular weight is 110.05, the appearance is a colorless transparent liquid with a slight fragrance, the boiling point is 170°C, and the relative density is 1.20. It is soluble in water and easily soluble in most organic solvents such as alcohol and ether. The preparation method of dimethyl phosphite is obtained by the direct reaction of methanol and phosphorus trichloride. The specific methods include: solvent reaction and solvent-free reaction. The specific methods include vapor-liquid reaction, vapor-vapor reaction, discontinuous method, continuous method, etc. Because the reaction is a violent exothermic reaction, the reaction speed is fast, and it is completed in an instant. The discontinuous method has frequent operations, high labor intensity, lo...

Examples

Embodiment 1

[0013] Connect the methanol storage tank with the methanol injector, connect the phosphorus trichloride storage tank with the phosphorus trichloride injector, and connect with the esterification reactor, start the agitator of the esterification reactor to stir, methanol and trichloride At the same time, phosphorus is slowly sprayed into the esterification reactor in the form of mist. The molar ratio of the injected amount is methanol:phosphorus trichloride=3:1. The reaction is exothermic. The reaction temperature is controlled at 48°C by controlling the injected amount of methanol Between, after the reaction is completed, the solid in the esterification reactor is the crude dimethyl phosphite, and the gas is the by-product hydrogen chloride and methyl chloride, which are discharged and collected for other purposes, and the solid dimethyl phosphite crude into the neutralization tank. Because the crude product of dimethyl phosphite is acidic, add an appropriate amount of ammonia...

Embodiment 2

[0016] Connect the methanol storage tank with the methanol injector, connect the phosphorus trichloride storage tank with the phosphorus trichloride injector, and connect with the esterification reactor, start the agitator of the esterification reactor to stir, methanol and trichloride At the same time, phosphorus is slowly sprayed into the esterification reactor in the form of mist. The molar ratio of the injected amount is methanol:phosphorus trichloride=3:1. The reaction is exothermic. The reaction temperature is controlled at 50°C by controlling the injected amount of methanol Between, after the reaction is completed, the solid in the esterification reactor is the crude dimethyl phosphite, and the gas is the by-product hydrogen chloride and methyl chloride, which are discharged and collected for other purposes, and the solid dimethyl phosphite crude into the neutralization tank. Because the crude product of dimethyl phosphite is acidic, add an appropriate amount of ammonia...

Embodiment 3

[0018] Connect the methanol storage tank with the methanol injector, connect the phosphorus trichloride storage tank with the phosphorus trichloride injector, and connect with the esterification reactor, start the agitator of the esterification reactor to stir, methanol and trichloride At the same time, phosphorus is slowly sprayed into the esterification reactor in the form of mist. The molar ratio of the injected amount is methanol:phosphorus trichloride=3:1. The reaction is exothermic. The reaction temperature is controlled at 52°C by controlling the amount of methanol injected Between, after the reaction is completed, the solid in the esterification reactor is the crude dimethyl phosphite, and the gas is the by-product hydrogen chloride and methyl chloride, which are discharged and collected for other purposes, and the solid dimethyl phosphite crude into the neutralization tank. Because the crude product of dimethyl phosphite is acidic, add an appropriate amount of ammonia...