Phosphotungstic heteropolyacid salt catalyst for synthesizing epoxy chloropropane and preparation method thereof

Abstract

The invention discloses a preparation method of a temperature control phase transfer catalyst for synthesizing epoxy chloropropane, and belongs to the field of catalytic chemistry. The preparation method comprises the following steps: dissolving K-type phosphotungstic acid in 30% hydrogen peroxide, carrying out an oxidation reaction to obtain a peroxyphosphotungstic acid aqueous solution, dropwiseadding the peroxyphosphotungstic acid aqueous solution into an ethanol solution of dimethyl dioctadecyl ammonium chloride, and carrying out a stirring reaction at 40 DEG C for 2 h; and after the reaction is finished, filtering a reaction product to obtain white powder, and carrying out water washing, absolute ethyl alcohol washing and vacuum drying to obtain the dimethyl dioctadecyl peroxy phosphotungstic acid catalyst. According to the method, the dimethyl dioctadecyl peroxyphosphotungstic acid is used as a catalyst, chloropropene and hydrogen peroxide are used as raw materials, and under the condition of no solvent or additive, the yield of epoxy chloropropane prepared by a one-pot method reaches 97.1%, the selectivity is greater than 99%, and the product yield is up to 96% or above. After the reaction is finished, the catalyst is dissolved in epoxy chloropropane, the catalyst is separated out when the temperature is reduced to 10 DEG C, and the catalyst is recycled through a filtering method. The catalytic reaction process is simple to operate, mild in reaction condition, low in production cost, stable in catalyst property, convenient to recycle and beneficial to industrial production.

Description

technical field [0001] The invention relates to the field of catalytic chemistry, in particular to a phosphotungstic heteropolysalt catalyst for synthesizing epichlorohydrin and a preparation method thereof. Background technique [0002] Epichlorohydrin is an important organic synthesis intermediate and fine chemical product. 85% of the world's epichlorohydrin is used to produce epoxy resin. my country is the largest producer and consumer of epoxy resin. The high-temperature chlorination of propylene and the propylene acetate method are the main processes for the production of epichlorohydrin at this stage. Although these two methods are mature and stable in operation, they both inevitably produce waste water, and the production energy consumption is high, which seriously corrodes the equipment. . Therefore, it is of great significance to develop a simple, efficient and green synthesis process for epichlorohydrin. [0003] As a green oxygen source, hydrogen peroxide has be...

AI Technical Summary

Problems solved by technology

However, additional organic solvents and phosphate additives were used in the catalytic reaction system, and the conversion rate of propylene was only 93%

Similarly, the patent CN100575349C reports that excess chloropropene is used in the presence of catalyst phosphotungstic acid and cocatalyst alkylphenol polyoxyethylene ether, and hydrogen peroxide is used as oxidant to directly generate epichlorohydrin. Excess chloropropene and Organic additives, not conducive to industrial production

Images