Process for directly synthesizing caprolactam from cyclohexanone and hydroxylamine

A technology of caprolactam and cyclohexanone, which is applied in the field of organic chemical synthesis, can solve the problems of energy consumption in the separation of intermediate products, and achieve the effects of improving effective utilization, reducing floor space, and not corroding equipment

Inactive Publication Date: 2012-05-02
HEBEI UNIV OF TECH
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] The technical problem to be solved by the present invention is to provide a process for synthesizing caprolactam in one step from cyclohexanone and hydroxylamine in the phosphate buffer solution system in view of the problems of intermediate product separation and energy consumption in the existing production technology

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
  • Process for directly synthesizing caprolactam from cyclohexanone and hydroxylamine

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] Room temperature ionic liquid N, N, N-trimethyl-N-sulfobutyl-ammonium bisulfate is synthesized according to the method of Chinese patent, application number 200710151000.1:

[0024] In the first step, take an aqueous solution of trimethylamine containing 0.5 mol of trimethylamine and 0.5 mol of 1,4-butane sultone, put them in a 250 ml three-necked flask, and stir and react at room temperature for 12 hours.

[0025] In the second step, the reaction solution obtained in the first step is taken out and subjected to rotary evaporation to remove water to obtain a white zwitterionic solid.

[0026] In the third step, the substance obtained in the second step is washed successively with absolute ethanol, toluene and anhydrous ether, and then vacuum-dried to constant weight at 80 ° C to obtain the zwitterion N, N, N-trimethyl-N- sulfobutyl ammonium.

[0027] In the fourth step, take 0.5 mol of the white zwitterionic solid obtained in the third step and put it into a four-necke...

Embodiment 2

[0029] Dissolve 0.031mol of sodium nitrate and 0.028mol of sodium hydroxide in 10ml of water in a 250mL three-necked bottle, and then add 2.63mL of H 3 PO 4 solution (containing 0.045mol phosphoric acid), add water to make 15mL phosphate buffer solution, add hydroxylamine sulfate 0.006mol, cyclohexanone 0.012mol (1.26ml) to the buffer solution, and place the three-necked flask in a 50°C water bath for magnetic stirring reaction . After reacting for 30min, add 0.0366mol (10.7g) of the room temperature ionic liquid N,N,N-trimethyl-N-sulfobutyl-ammonium bisulfate prepared in Example 1, and stop the reaction after reacting for 20min under normal pressure . Extract with dichloromethane several times, each time using 5mL, combine the extracts, and analyze the extracts directly on a gas chromatograph. The reaction result is that the conversion rate of cyclohexanone is 12.4%, and the selectivity of caprolactam is 84.2%.

Embodiment 3

[0031] The steps are the same as in Example 2, except that the reaction is stopped after adding the room temperature ionic liquid N,N,N-trimethyl-N-sulfobutyl-ammonium bisulfate prepared in Example 1 for 30 minutes. As a result of the reaction, the conversion rate of cyclohexanone was 13.2%, and the selectivity of caprolactam was 89.9%.

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

No PUM Login to view more

Abstract

The invention discloses a process for directly synthesizing caprolactam from cyclohexanone and hydroxylamine, comprising the following steps of: mixing sodium hydroxide, sodium nitrate, phosphoric acid and water to obtain a phosphoric acid buffer solution in a reactor; adding hydroxylamine sulfate and cyclohexanone in the ratio of 1:2 into the buffer solution, wherein the addition amount is that the volume ratio of 85 percent of phosphoric acid to the cyclohexanone is 2.63:1.26; reacting under normal pressure for 5-30min at 30-50 DEG C; and after the reaction time reaches, directly adding ionliquid of N,N,N-trimethyl-N-sulfonate butyl-ammonium bisulfate in a reaction mixture and reacting for 10-30min to obtain a product of the caprolactam, wherein the mole ratio of the N,N,N-trimethyl-N-sulfonate butyl-ammonium bisulfate to the cyclohexanone is 1:3-5. In the process for directly synthesizing the caprolactam from the cyclohexanone and the hydroxylamine in a phosphoric acid buffer solution system, the highest selectivity of the caprolactam can reach 92.1 percent.

Description

technical field [0001] The invention relates to the synthesis of organic chemical industry, in particular to a process for directly synthesizing caprolactam from cyclohexanone and hydroxylamine. technical background [0002] Caprolactam (CPL) is one of the important organic chemical raw materials. It is mainly used to prepare caprolactam resin, caprolactam fiber and artificial leather. It can be processed into nylon-6 fiber, nylon-6 resin and nylon-6 film, and can also be used as medicine. raw material. It is widely used in industries such as automobiles, ships, electronic appliances, industrial machinery, textiles, components of daily consumer goods, and food preservation films. In recent years, with the development of a new environment-friendly process for the synthesis of high-quality chemical fibers from caprolactam and nylon-6, the technology of clean production of caprolactam has become a hot spot in the chemical industry at home and abroad. [0003] The current indu...

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 Patents(China)
IPC IPC(8): C07D223/10C07D201/06
Inventor 王荷芳刘莎王延吉韩丽娟赵江琨
Owner HEBEI UNIV OF 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