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

Method for refining 4B acid using liquid alkali

A technology of B acid and liquid alkali, applied in the field of dye intermediate preparation, can solve the problems of high volatility of ammonia water, increase the difficulty of wastewater treatment, high volatility, etc., and achieve good quality results

Inactive Publication Date: 2018-12-21
宜宾市南溪区红源化工有限公司
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] However, the use of ammonia water for reaction has the following disadvantages: ammonia water is highly volatile during transportation and storage, and is prone to produce explosive mixed gases; ammonia water is highly volatile and produces pungent gas, which is harmful to operators; The presence of ammonium ions makes the COD of wastewater as high as 18,000, which increases the difficulty of wastewater treatment

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] Add p-toluidine and concentrated sulfuric acid into the sulfonation reaction kettle, carry out sulfonation baking, the reaction temperature is 180°C, the reaction pressure is -0.08Mpa, and the 4B acid crude product is obtained; the prepared 4B acid crude product is transferred to the dissolution kettle , according to the volume ratio of 1:5, add water and stir, add NaOH solution with a concentration of 30% during the stirring process, and carry out liquid alkali hydrolysis reaction. 4B salt is dissolved; the water-soluble 4B salt is transferred to the decolorization kettle, and the mass ratio of 2.0% is added to the activated carbon for decolorization, and the decolorization time is 25 minutes; the activated carbon is removed by filtration, and the water-soluble 4B salt Sulfuric acid with a concentration of 98% was added to the acid precipitation treatment, and the pH value of the solution after the acid precipitation treatment was 2; the solution after the acid precipit...

Embodiment 2

[0022] Add p-toluidine and concentrated sulfuric acid into the sulfonation reaction kettle, carry out sulfonation baking, the reaction temperature is 185°C, the reaction pressure is -0.08Mpa, and the 4B acid crude product is obtained; the prepared 4B acid crude product is transferred to the dissolution kettle , according to the volume ratio of 1:5, add water for stirring, add NaOH solution with a concentration of 30% during the stirring process, and carry out liquid alkali hydrolysis reaction, the pH value of the solution after the reaction is 7.8, and then raise the temperature to 95 ° C 4B salt is dissolved; the water-soluble 4B salt is transferred to the decolorization kettle, and the mass ratio of 2.5% is added to the activated carbon for decolorization, and the decolorization time is 15 minutes; the activated carbon is removed by filtration, and the water-soluble 4B salt Sulfuric acid with a concentration of 98% was added to the acid precipitation treatment, and the pH val...

Embodiment 3

[0024] Add p-toluidine and concentrated sulfuric acid into the sulfonation reaction kettle, carry out sulfonation baking, the reaction temperature is 190°C, the reaction pressure is -0.08Mpa, and the 4B acid crude product is obtained; the prepared 4B acid crude product is transferred to the dissolution kettle , according to the volume ratio of 1:5, add water to stir, add NaOH solution with a concentration of 30% during the stirring process, and carry out liquid alkali hydrolysis reaction. 4B acid salt is dissolved; the water-soluble 4B salt is transferred to the decolorization kettle, and the mass ratio of 2.3% is added to the activated carbon for decolorization, and the decolorization time is 20 minutes; Sulfuric acid with a concentration of 98% was added to the acid precipitation treatment, and the pH value of the solution after the acid precipitation treatment was 2; the solution after the acid precipitation treatment was cooled and crystallized in the reaction kettle, and t...

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 refining 4B acid using liquid alkali. The method comprises the following steps: adding p-toluidine and concentrated sulfuric acid to a sulfonation reactor, performing sulfonation baking to obtain crude 4B acid; transferring the prepared crude 4B acid to a dissolution vessel, and then adding a 30 percent NaOH solution to perform a liquid alkali hydrolysis reaction to obtain a water-soluble 4B acid salt; transferring the water-soluble 4B acid salt to a decolorization vessel, adding activated carbon with the mass ratio of 2.0-2.5 percent, and performing decolorizing treatment; removing activated carbon by filtration, adding 98 percent sulfuric acid to the decolorized water-soluble 4B acid salt to perform acid precipitation treatment; cooling and crystallizing a solution subject to acid precipitation treatment in a reaction vessel, separating and drying precipitated crystals to obtain a refined 4B acid product. The method has the beneficial effectsthatthe purity of the prepared 4B acid product is 99 percent or more; no harmful gas is generated during the production process; the COD of wastewater is reduced from original 18000 to about 10000.

Description

technical field [0001] The invention relates to the technical field of preparation of dye intermediates, in particular to a method for refining 4B acid with liquid caustic soda. Background technique [0002] 4B acid (2-amino-5-methylbenzenesulfonic acid, chemical formula: C 7 h 9 NO 3 S) is an important dye intermediate, commonly used in the manufacture of organic dyes and pigments such as Brilliant Red 6B, Lisol Baohong BK, and Reactive Brilliant Orange. In the prior art, the refining of the crude 4B acid is to put the 4B acid into hot water and then add ammonia water with a concentration of 20% to form a water-soluble 4B acid salt, and then carry out decolorization and refining. The reaction chemical formula that generates water-soluble 4B salt is: [0003] CH 3 C 6 h 3 (HSO 3 )NH 2 +NH 4 OH=CH 3 C 6 h 3 (NH 4 SO 3 )NH 2 +H 2 o [0004] However, the use of ammonia water for reaction has the following disadvantages: ammonia water is highly volatile during ...

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): C07C303/44C07C303/02C07C309/46
CPCC07C303/02C07C303/06C07C303/32C07C303/44C07C309/46
Inventor 李文生唐邦正杨建平
Owner 宜宾市南溪区红源化工有限公司