Unlock instant, AI-driven research and patent intelligence for your innovation.

A method for preparing 3,3',4,4'-tetraaminodiphenyl ether hydrochloride by catalytic hydrogenation

A technology of tetraaminodiphenyl ether and -diaminodiphenyl ether, which is applied in the field of organic synthesis, can solve the problems of high toxicity, high cost, strong corrosiveness and the like, and achieves the effects of low production cost, less three wastes and good quality

Active Publication Date: 2016-06-29
CHINA PETROLEUM & CHEM CORP +1
View PDF1 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method is costly, highly corrosive, and highly toxic, and is gradually being phased out.
At present, the chemical reduction method is used in the domestic small-scale test of this product. There are various disadvantages in this process, and the method of catalytic hydrogenation needs to be improved for technical improvement.

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
  • A method for preparing 3,3',4,4'-tetraaminodiphenyl ether hydrochloride by catalytic hydrogenation

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0021] Make methanol and dimethylformamide into a mixed solvent at a molar ratio of 1:0.5, and then mix the raw material 3,3'-dinitro-4,4'-diaminodiphenyl ether with a molar ratio of 1:6 Prepare the raw material solution and put it in a container. Install the granular supported 5%Pd / C catalyst in the fixed bed, and use N 2 After 3 replacements, use H 2 Replace 3 times. Access to H 2， And adjust the pressure in the fixed bed to 3MPa, then pump into the mixed solvent with a speed of 50ml / hour, after the solvent is mixed with hydrogen, enter the fixed bed reactor through a preheater. Slowly increase the temperature of the preheater and the fixed bed, and when the temperature reaches 180°C, keep it for several hours until the solvent fills the fixed bed reactor. At this temperature, the system pressure was adjusted to 1.0 MPa, the material was replaced with raw material solution, the feed rate was adjusted to 20 ml / hour, and the reducing solution overflowed from the top of the...

Embodiment 2

[0023] The operating conditions are the same as in Example 1, except that the molar ratio of methanol to dimethylformamide is adjusted to 1:2 mixed solvent, and the molar ratio of 3,3'-dinitro-4,4'-diaminodiphenyl ether to mixed solvent Adjusted to 1:10 to prepare the raw material solution, the purity of the finished product was 94.9% (HPLC), and the yield was 88.2%.

Embodiment 3

[0025] The operating conditions are the same as in Example 1, except that the molar ratio of methanol to dimethylformamide is adjusted to 1:4.5 mixed solvent, and the molar ratio of 3,3'-dinitro-4,4'-diaminodiphenyl ether to mixed solvent Adjusted to 1:15 to prepare the raw material solution, the purity of the finished product was 89.5% (HPLC), and the yield was 70.6%.

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 belongs to the technical field of organic synthesis, and in particular relates to a method for preparing 3,3′,4,4′-tetraaminodiphenyl ether hydrochloride through fixed-bed catalytic hydrogenation. First, the raw material 3,3′-dinitro-4,4′-diaminodiphenyl ether, methanol, and dimethylformamide mixed solvent were prepared into a solution with a molar ratio of 1:5~20, and 0.5 %~10% of the supported Pd / C catalyst, and replaced with nitrogen and hydrogen respectively. At a temperature of 50-250° C. and a hydrogen pressure of 0.5-4 MPa, the raw material solution is pumped into a preheater by a metering pump through a continuous feeding and discharging method, and then enters a fixed-bed reactor for catalytic hydrogenation. After the reaction, under the protection of nitrogen, the reaction liquid is added to the hydrochloric acid solution containing the reducing agent to remove the solvent, and finally the finished product is obtained. The method has the advantages of low product cost, good quality, high yield and less three wastes. In addition, the process can avoid the separation step of the target product and the powdered catalyst, saves time and effort, is economical and environmentally friendly, easy to operate, and easy to realize industrialization.

Description

technical field [0001] The invention belongs to the technical field of organic synthesis, in particular to a method for preparing 3,3',4,4'-tetraaminodiphenyl by catalytic hydrogenation of 3,3'-dinitro-4,4'-diaminodiphenyl ether Ether hydrochloride method. The method involves a modified monomer 3,3',4,4'- A method for preparing tetraaminodiphenyl ether by catalytic hydrogenation. Background technique [0002] Polybenzimidazole (PBI) is a very desirable fiber with higher thermal stability, chemical stability and comfort. At first, PBI fibers were mainly used in flame-retardant space suits, firefighting suits, military uniforms, chemical equipment, petrochemical and other fields. In recent years, the application fields of PBI materials have become more and more extensive, and have been used in automobile brakes, large aircraft, high-speed rail and fuel cell membranes. 3,3',4,4'–Tetraaminodiphenyl ether (TADE) is a modified monomer for PBI fibers. Due to the introduction o...

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): C07C217/90C07C213/02
Inventor 杨怀青黄伟管庆宝
Owner CHINA PETROLEUM & CHEM CORP