阅读说明：本技术 一种制备甲氧基丙酮的方法 (Method for preparing methoxy acetone ) 是由 张恩锋 王炳春 王贤彬 李进 于 2019-10-24 设计创作，主要内容包括：本发明公开了一种制备甲氧基丙酮的方法,将甲氧基丙醇与TS-1催化剂混合倒入带有夹套的反应釜中,采用循环水浴加热至30～50℃,然后向其中滴加双氧水,保温2～6小时,得到反应液,经过滤、精馏得到甲氧基丙酮纯品。该反应甲氧基丙醇转化率大于70％,甲氧基丙酮收率达到60％。反应采用TS-1分子筛为催化剂,具有环保、后处理简单的优点。反应条件温和,操作工艺简单,产品收率高,适合工业化生产。(The invention discloses a method for preparing methoxy acetone, which comprises the steps of mixing methoxy propanol and a TS-1 catalyst, pouring the mixture into a reaction kettle with a jacket, heating the mixture to 30-50 ℃ by adopting a circulating water bath, then dropwise adding hydrogen peroxide into the mixture, keeping the temperature for 2-6 hours to obtain a reaction solution, and filtering and rectifying the reaction solution to obtain a pure methoxy acetone product. The conversion rate of the methoxy propanol is more than 70%, and the yield of the methoxy acetone reaches 60%. The reaction adopts a TS-1 molecular sieve as a catalyst, and has the advantages of environmental protection and simple post-treatment. The reaction condition is mild, the operation process is simple, the product yield is high, and the method is suitable for industrial production.)

1. A method for preparing methoxy acetone is characterized in that: mixing the methoxy propanol and the TS-1 catalyst, pouring the mixture into a reaction kettle, heating, dropwise adding hydrogen peroxide into the mixture, preserving heat to obtain a reaction solution, and filtering and rectifying the reaction solution to obtain a product of methoxy acetone.

2. The method for preparing methoxy acetone as claimed in claim 1, wherein the reaction kettle is jacketed and heated by circulating water bath.

3. The method for preparing methoxy acetone according to claim 1, wherein the mass ratio of methoxy propanol to TS-1 catalyst is (5-10): 1.

4. the method for preparing methoxy acetone according to claim 2, wherein the heating temperature of the circulating water bath is 30-50 ℃.

5. The method for preparing the methoxy acetone as claimed in claim 1, wherein the molar ratio of the methoxy propanol to the hydrogen peroxide is (1-4): 1.

6. the method for preparing methoxy acetone according to claim 1, wherein the holding time is 2-6 hours.

Technical Field

The invention relates to a method for preparing methoxy acetone, in particular to a method for preparing methoxy acetone by catalytic oxidation of a molecular sieve.

Background

Methoxy acetone is an important raw material in the synthesis of the low-toxicity pesticide metolachlor. Metolachlor has been widely used in dry farmland in the north as a low-toxicity herbicide. Methoxy acetone is one of the important raw materials for producing metolachlor, and has wide market space.

The synthesis method of methoxy acetone is mainly prepared by oxidizing methoxy propanol serving as a raw material, and the synthesis methods reported in the literature and patents at present comprise: 1. oxidizing agents such as sodium dichromate and the like are used as raw materials to synthesize the methoxy acetone through oxidation, and heavy metal chromium seriously pollutes the environment. 2. The hydrogen peroxide is used as an oxidant to oxidize the methoxy propanol to synthesize the methoxy acetone, the catalyst is sodium tungstate, the using amount of the catalyst is large, other organic solvents are required to be added, and the subsequent treatment steps are increased. 3. The dehydrogenation method for synthesizing the methoxy acetone needs to be carried out in a tubular reactor, the design and the operation process of the reactor are complex, the equipment investment is large, the reaction temperature is high, the catalyst is difficult to recover, and the conversion rate of raw materials is low, so that the improvement is worth to be carried out.

Disclosure of Invention

The invention relates to a method for preparing methoxy acetone, wherein an environment-friendly TS-1 molecular sieve is selected as a catalyst, circulating water bath heating is adopted, the temperature is 30-50 ℃, the reaction condition is mild, and the operation process is simple. Filtering, rectifying and crystallizing the reaction liquid to obtain a pure methoxy acetone product. The conversion rate of the methoxy propanol is more than 70%, and the yield of the methoxy acetone reaches 60%. The invention makes up the defects of the prior art and is suitable for industrial production.

The invention is realized by the following technical scheme:

a method for preparing methoxy acetone is characterized in that: mixing methoxypropanol and a TS-1 catalyst, pouring the mixture into a reaction kettle with a jacket, heating the mixture by adopting a circulating water bath, dropwise adding hydrogen peroxide into the mixture, preserving the heat to obtain a reaction solution, and filtering, rectifying and crystallizing the reaction solution to obtain a pure product of the methoxy acetone.

The method for preparing the methoxy acetone is characterized in that the mass ratio of the methoxy propanol to the TS-1 catalyst is (5-10): 1, preferably (5-6): 1.

the method for preparing the methoxy acetone is characterized in that the heating temperature of the circulating water bath is 30-50 ℃, and preferably 35-40 ℃.

The method for preparing the methoxy acetone is characterized in that the molar ratio of the methoxy propanol to the hydrogen peroxide is (1-4): 1, preferably (1-2): 1.

the method for preparing methoxy acetone is characterized in that the heat preservation time is 2-6 hours, preferably 3-4 hours.

Filtering, rectifying and crystallizing the reaction liquid to obtain a pure methoxy acetone product. The conversion rate of the methoxy propanol is more than 70%, and the yield of the methoxy acetone reaches 60%.

Detailed Description

The following examples further illustrate the technical solutions of the present invention, but should not be construed as limiting the scope of the present invention.

The TS-1 catalyst in the following examples is prepared according to a TS-1 titanium silicalite molecular sieve and a preparation method and application thereof (201310369673.X), but is not limited to the TS-1 catalyst prepared by the method.