Full continuous flow synthesis process for 2-methyl-1,4-naphthoquinone

A fully continuous, flow synthesis technology, applied in the field of chemistry, can solve the problems of unstable product quality, large consumption of oxidant, low production efficiency, etc., and achieve the effect of shortening the total reaction time, reducing excessive oxidation and improving production efficiency.

Active Publication Date: 2018-07-20
SHANGHAI HYBRID CHEM TECH
View PDF11 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0022] Aiming at the shortcomings in the prior art such as unstable product quality, long reaction time, low production efficiency, large consumption of oxidant, many by-products, poor safety, and amplification effect, the problem to be solved by the present invention is to provide a safe, Rapid, efficient, stable, and easy-to-scale-up production of fully continuous flow synthesis process of 2-menadione and a device capable of realizing the process

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Full continuous flow synthesis process for 2-methyl-1,4-naphthoquinone
  • Full continuous flow synthesis process for 2-methyl-1,4-naphthoquinone
  • Full continuous flow synthesis process for 2-methyl-1,4-naphthoquinone

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0096] Embodiment 1#~12#

[0097] The molten 2-methylnaphthalene and emulsifier solution are emulsified by a constant flow feed pump. The "dynamic" milk flow after emulsification enters the continuous flow reactor directly without stopping. Sodium dichromate solution and a stream of sulfuric acid solution are also fed into the reactor 2-methylnaphthalene through a constant flow feed pump to react. Emulsification time is RT e , the reaction temperature is T, and the oxidation reaction time is RT r . The formula for calculating the total reaction time is: RT=RT e +RT r .

[0098] where emulsification time RT e The calculation formula is

[0099]

[0100] Oxidation reaction time RT r The calculation formula is similar to the emulsification time calculation.

[0101] Concrete embodiment condition and result are shown in the following table.

[0102]

[0103]

Embodiment 13

[0104] Embodiment 13#~18#

[0105] The molten 2-methylnaphthalene and emulsifier solution are emulsified by a constant flow feed pump. The difference from Examples 1# to 12# is that the sulfuric acid solution is divided into three streams with different concentrations and different flow rates, and the sulfuric acid solution is pumped into different positions of the reactor. The temperature from the first addition of sulfuric acid solution to the second addition of sulfuric acid solution is set as T 1 , the reaction time is RT r1 , the temperature between the addition of sulfuric acid solution for the second time and the addition of sulfuric acid solution for the third time is set to T 2 , the reaction time is Rt r2 , the temperature between the third time sulfuric acid solution is added to the outlet is set to T 3 , the reaction time is RT r3 , the total reaction time is RT, and the calculation formula is RT=RT e +RT r1 +RT r2 +RT r3 . The calculation principle of ea...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
particle diameteraaaaaaaaaa
particle diameteraaaaaaaaaa
sizeaaaaaaaaaa
Login to view more

Abstract

The invention relates to a full continuous flow synthesis process for 2-methyl-1,4-naphthoquinone and an integrated continuous flow reactor for implementing the process. According to the synthesis process, 2-methylnaphthalene, an emulsifying agent solution, a sodium dichromate solution and a sulphuric acid solution are taken as raw materials; the synthesis process is performed in the integrated continuous flow reactor; the 2-methylnaphthalene, the emulsifying agent solution, the sodium dichromate solution and the sulphuric acid solution are added into a feeding port of the integrated continuous flow reactor uninterruptedly; continuously performing transient emulsion process and oxidation process, then the 2-methyl-1,4-naphthoquinone is uninterruptedly obtained at a discharging port of theintegrated continuous flow reactor; the reaction time is less than or equal to 700 seconds. The process is a continuous synthesis process for the 2-methyl-1,4-naphthoquinone, which is quick, safe, high in efficiency and high in universality, and facilitates large-scale production.

Description

technical field [0001] The invention relates to the field of chemistry, in particular to a fully continuous flow synthesis process for 2-methyl-1,4-naphthoquinone. Background technique [0002] 2-methyl-1,4-naphthoquinone, referred to as β-menadione or 2-menaquinone, is a fat-soluble vitamin and a key intermediate for the synthesis of K-series vitamins. 2-Menadione has a wide range of applications, and is widely used in clinical, agriculture, forestry, coatings and other fields. It is difficult to extract natural 2-menadione, so currently 2-menaquinone mainly depends on artificial synthesis. There are many methods for chemically synthesizing 2-menaquinone: gas phase oxidation, chemical oxidation, etc. The gas-phase oxidation method uses air to oxidize 2-methylnaphthalene in a gaseous state, and the yield of the product is low and there are many impurities. The chemical oxidation method mainly includes the hydrogen peroxide method and the chromium salt method according to ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C07C46/02C07C50/12
CPCC07C46/02C07C50/12C07C46/04C07C50/10
Inventor 马兵马陈雷刘学潘帅
Owner SHANGHAI HYBRID CHEM TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products