Synthesis method of p-phenylenediame

A synthesis method and technology for p-phenylenediamine, which are applied in chemical instruments and methods, preparation of amino compounds, preparation of organic compounds, etc., can solve the problems of low total product yield, three-waste pollution, and low selectivity, and achieve product purity. Good, less environmental pollution, high reaction yield

Active Publication Date: 2010-03-10
CHIZHOU FANGDA SCI & TECH CO LTD +1
View PDF0 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the reduction method using p-nitroaniline is generally made of aniline as a raw material, and the amino group is first protected, then nitrated and then reduced, and the process route is relatively long; The bottom residual liquid is mainly p-dichlorobenzene, and after purification, p-dichlorobenzene reacts with liquid ammonia under high temperature, pressure, and copper catalysis
For the reduction of nitro, the iron powder reduction method is often used in industry, and the cost is high and the three wastes are seriously polluted.
The ammonolysis method of p-dichloroaniline has the advantage of utilizing the by-products remaining after the production of chlorobenzene, which is also waste utilization in this sense, but the reaction requires high pressure, low selectivity, and low total yield of products

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
  • Synthesis method of p-phenylenediame

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0018] In a 500mL three-necked flask, add 138g (1 mole) of p-nitroaniline, 300ml of ethanol, and 0.1 mole of a magnetic solid base catalyst, stir and heat to dissolve p-nitroaniline, raise the temperature to 50°C, and slowly add 96g of hydrazine hydrate dropwise (3 moles), after dropping for 1 hour, heat preservation reaction for 5 hours, filter while hot, add 500ml water, adjust the solution to be alkaline, then leave standstill, separate out white crystal p-phenylenediamine 82g, productive rate is 76%.

[0019] Product melting point: 138-140°C, purity 98% (HPLC analysis conditions: chromatographic column C18, Φ4.0×200mm, column temperature 30°C, mobile phase 30% methanol-70% 0.02M phosphate buffer). IR(KBr)cm -1 : 3450, 3400, 3205, 1640, 1520, 1270.

Embodiment 2

[0021] In a 500mL three-necked flask, add 138g (1 mole) of p-nitroaniline, 300mL of ethanol, and 0.05 mole of magnetic solid base catalyst, stir and heat to dissolve p-nitroaniline, raise the temperature to 100°C, and slowly add 64g of hydrazine hydrate dropwise (2 moles), after dropping for 1 hour, heat preservation reaction for 10 hours, filter while hot, add 500mL water, adjust the solution to be alkaline, leave standstill, separate out white crystal p-phenylenediamine 76g, yield rate is 70%.

Embodiment 3

[0023] In a 500mL three-necked flask, add 138g (1 mole) of p-nitroaniline, 300mL of ethanol, and 0.01 mole of a magnetic solid base catalyst, stir and heat to dissolve p-nitroaniline, raise the temperature to 50°C, and slowly add 320g of hydrazine hydrate dropwise (10 moles), after dropping for 1 hour, heat preservation reaction for 20 hours, filter while hot, add 500mL water, adjust the solution to be alkaline, leave standstill, separate out white crystal p-phenylenediamine 81g, yield rate is 75%.

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 synthesis method of p-phenylenediame. The method comprises the following steps: placing magnetic Mg / Al-hydrotalcite solid base catalyst and p-nitroaniline in a reaction container, heating, slowly dropping hydrazine hydrate to react at 0-100 DEG C for 0.5-20h, filtrating the hot reaction solution after the reaction, cooling, standing to precipitate white crystals, then filtrating the postcrystalline reaction solution, and drying to obtain the finished product. The invention adopts magnetic solid base as catalyst, uses hydrazine hydrate to reduce the nitryl group, reduces the emission of three wastes in the reaction process, simplifies the technology, increases the yield and purity of the product and ensures that the synthesis technology is suitable for industrialization.

Description

technical field [0001] The invention relates to the field of industrial synthesis, in particular to a synthesis method of p-phenylenediamine. Background technique [0002] The development of new and efficient catalysts, the simplification of reaction steps, the reduction of pollution emissions, the development of new clean production technologies, the realization of efficient chemical reactions, and the realization of "zero emissions" have important application value in the field of green chemistry. [0003] p-Phenylenediamine is an extremely important dye intermediate. This product is mainly used as a raw material for aramid fibers, azo dyes, sulfur dyes, acid dyes, textile fibers, rubber antioxidants, and developers. It can also be used as rubber antioxidant DNP , DOP, and MB production; it can also be used as cosmetic hair dye Wuersi D series; gasoline polymerization inhibitor and developer raw material; it is used in gasoline polymerization inhibitor, aircraft coating, b...

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): C07C211/51C07C209/36B01J21/10
Inventor 陈方兰亚玲裴文
Owner CHIZHOU FANGDA SCI & TECH CO LTD
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap