Method and specially used apparatus for ortho-dichlorobenzene continuous mononitration reaction

A technology of o-dichlorobenzene and a special device, which is applied in the field of continuous mononitration reaction of o-dichlorobenzene, can solve the problems of reactor mass transfer, low heat transfer efficiency, high content of dinitro impurities, and great safety hazards. Achieve the effect of overcoming uneven local concentration, high product yield and high safety

Inactive Publication Date: 2017-12-01
ZHEJIANG UNIV OF TECH
View PDF8 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] Among the above methods, mixed acid nitration is a commonly used method in industry. The nitration reaction is a strong exothermic reaction. The traditional kettle-type process exists: the mass transfer and heat transfer efficiency of the reactor is low, and it is

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
  • Method and specially used apparatus for ortho-dichlorobenzene continuous mononitration reaction

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0030] The first metering pump is used to transport o-dichlorobenzene, and the flow rate is set to 14.7kg / h (100mol / h); the second metering pump is used to transport nitrating agent A, wherein 98% nitric acid 5.5kg / h (85mol / h) ; 98% sulfuric acid 12kg / h (120mol / h); water 2.7kg / h. The third metering pump is used to transport nitrating agent B, wherein 1.3kg / h (20mol / h) of 98% nitric acid. The above-mentioned reaction device is used to carry out the nitration reaction. The first and second tubular reactors have a pipe diameter of 30mm and a pipe length of 20m. The raw material and nitrating agent A are transported synchronously by the pump to the first mixer and then enter the first tubular reactor. The temperature is maintained at 150°C. After staying for 36 minutes, the organic phase enters the second mixer after being separated by the first liquid separator. ; Turn on the third metering pump, and the nitrating agent B is mixed with the organic phase in the second mixer; the...

Embodiment 2

[0032] The first metering pump is used to transport o-dichlorobenzene, and the set flow rate is 147g / h (1mol / h); the second metering pump is used to transport nitrating agent A, wherein 98% nitric acid 55g / h (0.85mol / h); 98% sulfuric acid 120g / h (1.2mol / h); water 27g / h. The third metering pump is used to transport nitrating agent B, wherein, 98% nitric acid 13g / h (0.2mol / h), 98% sulfuric acid 200g / h (2mol / h), water 1760g / h. The above-mentioned reaction device is used to carry out the nitration reaction. The first and second tubular reactors have a pipe diameter of 1mm and a pipe length of 200m. The raw material and nitrating agent A are transported synchronously by the pump to the first mixer respectively, and then enter the first tubular reactor after being mixed. The temperature is maintained at 130°C, and after staying for 40 minutes, the organic phase enters the second mixer after being separated by the first liquid separator. ; Turn on the third metering pump, and the n...

Embodiment 3

[0034]The first metering pump is used to transport o-dichlorobenzene, and the flow rate is set to 147g / h (1mol / h); the second metering pump is used to transport nitrating agent A, wherein 98% nitric acid 55g / h (0.85mol / h); 98% sulfuric acid 120g / h (1.2mol / h); water 270g / h. The third metering pump is used to transport nitrating agent B, wherein 98% nitric acid 130g / h (0.2mol / h), 98% sulfuric acid 50g / h (0.5mol / h), water 4g / h. The above-mentioned reaction device is used to carry out the nitration reaction. The diameter of the first and second tubular reactors is 15 mm, and the length of the tube is 1 m.

[0035] The raw material and nitrating agent A are respectively transported synchronously by the pump to the first mixer for mixing and then enter the first tubular reactor. The temperature is maintained at 100°C, after staying for 45 minutes, the organic phase enters the second mixer after being separated by the first liquid separation device; the third metering pump is turne...

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 method and specially used apparatus for ortho-dichlorobenzene continuous mononitration reaction. The method is characterized in that raw materials are added into an ortho-dichlorobenzene metering tank; a nitrating agent A is added into a nitrating agent A metering tank; the raw materials and the nitrating agent A are separately input into a first mixer synchronously through a first metering pump and a second metering pump; a reaction is performed at a temperature of 100-200 DEG C for 15-50 min; a reaction solution A enters a first liquid separation device; after liquid separation, an organic phase A enters a second mixer and an inorganic phase A enters a waste acid receiving device; a nitrating agent B stored in a nitrating agent B metering tank is added into the second mixer through a third metering pump; a nitration reaction is performed in a second tube reactor at a temperature of 10-100 DEG C; a reaction solution B enters a second liquid separation device; after liquid separation, an inorganic phase B enters the waste acid receiving device and an organic phase B enters a product postprocessing device for obtaining a mononitration product. The concentration of sulfuric acid used in the preparation method provided by the invention is low, the raw material conversion is complete, the yield of the final product is high, multi-nitro by-products are less, and the safety is higher, so that the preparation method and the apparatus are suitable for industrialized production.

Description

(1) Technical field [0001] The invention relates to a method and a special device for continuous mononitration reaction of o-dichlorobenzene. (2) Background technology [0002] The mononitration products of o-dichlorobenzene, 2,3-dichloronitrobenzene and 3,4-dichloronitrobenzene, are important pharmaceutical and chemical intermediates, often used in the preparation of third-generation "fluoroquinolones" drugs, antihypertensive Blood pressure drugs, etc., can also be used to synthesize plant protection agents and fuels. [0003] The methods reported in the literature for o-dichlorobenzene mononitration reaction can be divided into three categories: (1) mixed acid isothermal nitration method: Cheng Xiulian et al. (Journal of Shenyang Institute of Technology, 1998, 1:104-108.) Under certain conditions, the method for preparing mononitro-ortho-dichlorobenzene by dropwise adding mixed acid composed of sulfuric acid / nitric acid to o-dichlorobenzene has a yield of 94.8% and a GC p...

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
IPC IPC(8): C07C201/08C07C205/12B01J19/24
CPCC07C201/08B01J19/0006B01J19/242B01J2219/00094C07C205/12
Inventor 余志群王文佐苏为科
Owner ZHEJIANG 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

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