Method for treating tail gas of thionyl chloride chlorination

A chlorination reaction, thionyl chloride technology, applied in the directions of chlorine/hydrogen chloride, chemical instruments and methods, separation methods, etc., can solve the problems of unapplied mixed acid, high environmental pressure, and high processing cost, and achieve complete absorption and lightening. The effect of environmental protection pressure and high treatment efficiency

Inactive Publication Date: 2008-02-13
GAOYOU CITY ORGANIC CHEM FACOTRY
View PDF0 Cites 21 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] Whether it participates in the chlorination reaction normally or is decomposed by water after the reaction, a large amount of hydrogen chloride and sulfur dioxide gas will be produced; if it is not treated, it will inevitably cause serious environmental pollution
[0007] The existing commonly used treatment method is hierarchical absorption: first absorb most of the mixed gas with water to obtain a mixture of hydrochloric acid and sulfur dioxide or sulfurous acid; then absorb the gas that has not been absorbed before with alkaline water to obtain alkali and chloride salts and sulfite mixed wa

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 for treating tail gas of thionyl chloride chlorination

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0027] The tail gas produced after the reaction of one mole of thionyl chloride with the alcoholic hydroxyl group is absorbed at 20°C by 70 grams of water (first-stage absorption), absorbed at 20°C by 70 grams of water (second-stage absorption) and composed of 40 grams of sodium hydroxide and 100 The aqueous solution prepared with gram of water is absorbed at 20°C (the third level of absorption) and then discharged. The exhaust gas is tested according to the method of the State Environmental Protection Administration standard HJ / T56-2000, and the sulfur dioxide content is 60mg / m 3 (to meet the emission requirements of the State Environmental Protection Administration). The sulfur dioxide content is 5.35 grams / 100 gram solution in the first stage absorption liquid (the concentrated hydrochloric acid that is obtained containing a small amount of sulfur dioxide), and the hydrogen chloride content is 38.50 grams / 100 gram solution; Sulfur dioxide content in the dilute hydrochloric ...

Embodiment 2

[0029] The tail gas produced after the reaction of one mole of thionyl chloride with the alcoholic hydroxyl group is absorbed through 76 grams of dilute acidic water at 20°C (the first level of absorption, the second level of absorption solution in Example 1, i.e. the dilute hydrochloric acid obtained), 70 grams Water is absorbed at 20°C (the second level of absorption, fresh water) and an aqueous solution prepared by 40 grams of sodium hydroxide and 100 grams of water is absorbed at 20°C (the third level of absorption) and then discharged. The exhaust gas is in accordance with the standard HJ / T56- 2000 method detection, sulfur dioxide content is 80mg / m 3 (to meet the emission requirements of the State Environmental Protection Administration). The content of sulfur dioxide in the first-stage absorption liquid is 5.27 g / 100 g solution, the content of hydrogen chloride is 37.85 g / 100 g solution; the content of sulfur dioxide in the second-stage absorption liquid is 5.45 g / 100 g ...

Embodiment 3

[0031] The tail gas produced after the reaction of one mole of thionyl chloride and the alcoholic hydroxyl group is absorbed through 79.5 grams of dilute acidic water at 20°C (the first level of absorption, the second level of absorption solution in Example 2), and 70 grams of water at 20°C (the second level of absorption). Secondary absorption, fresh water) and an aqueous solution prepared by 40 grams of sodium hydroxide and 100 grams of water at 20°C (third stage absorption) and then discharged, the exhaust gas is tested according to the method of the State Environmental Protection Administration standard HJ / T56-2000, sulfur dioxide The content is 70mg / m 3(to meet the emission requirements of the State Environmental Protection Administration). The content of sulfur dioxide in the first-stage absorption liquid is 5.43 g / 100 g solution, the content of hydrogen chloride is 38.65 g / 100 g solution; the content of sulfur dioxide in the second-stage absorption liquid is 5.30 g / 100 ...

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 for treating tail gas generated in chlorination reaction by using thionyl chloride. The existing traditional tail gas treatment method is costly due to a large amount of alkali consumption, and the pressure on environmental protection is high due to the final generation of a large amount of waste water containing heteroions. In the present invention, by controlling the amount of water, the hydrogen chloride in the tail gas is subjected to two-stage absorption with water, and the concentrated hydrochloric acid with a hydrogen chloride content close to saturation and a small amount of sulfur dioxide is obtained through the first-stage absorption; the second-stage absorption: after the first-stage absorption, the The exhaust gas is subjected to the second-stage absorption, and the added water is not discharged to obtain dilute hydrochloric acid containing a small amount of hydrogen chloride and a small amount of sulfur dioxide. The dilute hydrochloric acid is used as the raw material water for the first-stage absorption; after the above-mentioned secondary absorption treatment, it is then treated with alkali or alkali The third level of water absorption is used to absorb sulfur dioxide in the tail gas to obtain a relatively pure aqueous solution of sodium sulfite. The invention has high treatment efficiency, complete tail gas absorption, and reduces the pressure on environmental protection.

Description

technical field [0001] The invention relates to tail gas treatment of chemical reactions, in particular to a method for treating tail gas produced in chlorination reactions with thionyl chloride. Background technique [0002] Thionyl chloride (also known as sulfur oxychloride; thionyl chloride; thionyl chloride), molecular formula SOCl 2 , molecular weight 118.97, relative density 1.676 (4°C), melting point -104.5°C, boiling point 78.8°C, vapor density 4.1, vapor pressure 14.66kPa (110mmHg26°C), colorless to light yellow or light red smoking liquid, suffocating Odor, miscible with benzene, chloroform, and carbon tetrachloride, corrosive and irritating, decomposes into hydrogen chloride and sulfur dioxide when exposed to water, decomposes into chlorine gas, sulfur dioxide, and disulfur dichloride when heated above 140°C. As a basic chemical raw material, thionyl chloride is widely used in chlorination reactions, such as the chlorination of alcohol hydroxyl groups into chlori...

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): B01D53/50B01D53/68C01B7/01C01B17/62C01B17/46
Inventor 瞿军陆文辉钱跃言邓红霞章学兵吴宏祥刘伟沈润溥
Owner GAOYOU CITY ORGANIC CHEM FACOTRY
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