Method for synthesizing dichloropropanol by catalyzing glycerol for chlorination under existence of dicarboxylic acid-rare earth chloride

Abstract

The invention relates to a method for synthesizing dichloropropanol by catalyzing glycerol for chlorination under the existence of dicarboxylic acid-rare earth chloride, which comprises the following steps of: mixing glycerol and a dicarboxylic acid-rare earth chloride composite catalyst in a chloridizing reactor R-1, and then introducing chlorine hydride gas, constantly evaporating out water and partial dichloropropanol generated in the reactor; introducing chlorine hydride as a tail gas into a chloridizing reactor R-2 filled with the glycerol and the catalyst; after the chlorination of the reactor R-1 is ended, evaporating dichloropropanol by decompression and then adding the glycerol for further chlorination; during the distillation of the chloridizing reactor R-1, starting to introduce chlorine hydride into the chloridizing reactor R-2, and the chlorine hydride as the tail gas into a chloridizing reactor R-3, wherein the glycerol and the catalyst added into the chloridizing reactors R-1, R-2 and R-3 have the same dosage; after the chlorination of the chloridizing reactor R-2 is ended, repeating the procedures of distillation, feeding and chlorination in the chloridizing reactor R-1; connecting the chloridizing reactors R-1,R-2 and R-3 from head to tail, and introducing the chlorine hydride as the tail gas into the chloridizing reactor R-1 while introducing the chlorine hydride into the chloridizing reactor R-3; transferring a mixed liquor of the dichloropropanol, water and the chlorine hydride to a distillation still, and adding an organic solvent to remove water by azeotropy. The method has the advantages of high reaction speed, high utilization ratio of the chlorine hydride and high yield.

Description

1. Technical field [0001] The invention relates to a method and a reaction device for synthesizing dichloropropanol from glycerin. 2. Background technology [0002] Dichloropropanol is the precursor for the synthesis of epichlorohydrin. Epichlorohydrin is an important organic chemical raw material, which can be used in the synthesis of surfactants, medicines, pesticides, ion exchange resins, plasticizers, chlorohydrin rubber and many other products, and has a wide range of uses. The epoxy resin prepared from it has the characteristics of strong adhesion, chemical medium corrosion resistance and excellent dielectric properties. It is widely used in coatings, adhesives, reinforcing materials, wind turbine blades and other industries, and the consumption is huge. . my country is the largest producer and important consumer of epoxy resin in the world, and epichlorohydrin is mainly used in the production of epoxy resin. [0003] At present, there are mainly two industrial prod...

AI Technical Summary

Problems solved by technology

However, due to the use of a large amount of organic solvents in this method, there are disadvantages such as low utilization rate of equipment, large loss of hydrogen chloride and additional separation devices.

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