CN1465624A - Method for producing indigo - Google Patents

Abstract

The production method of indigo includes the following steps: placing aniline and hydroxyacetonitrile into condensation reactor according to the mole ratio of 1:0.9-1:1.2, reacting for 2-8 hr. at 60-105 deg.C, then placing all the materials into hydrolysis reactor, adding potassium hydroxide into the hydrolysis reactor according to the mole ratio of aniline and potassium hydroxide of 1:0.9-1:1.2, boiling and refluxing to make hydrolysis reaction, adopting acid to absorb the ammonia gas discharged by reaction, concentrating reactant material, drying to obtain white and light-yellow powder or flake potassium phenylglycinate, then making the potassium phenylglycinate, sodium hydroxide, potassium hydroxide and amino sodium undergo the process of alkali fusion oxidation reaction so as to obtain the invented product indigo.

Description

Indigo production method

Technical field:

The invention belongs to the technical field of chemical dyestuff, specifically a kind of improved indigo production method especially relates to condensation, the hydrolysis reaction of front two parts in the indigo production.

Background technology:

Indigo is a kind of vat dyes, be mainly used in the dyeing of cotton, linen, especially be applied to the dyeing of denim, the history in existing more than 100 year of indigo suitability for industrialized production, the production history that three more than ten years were also arranged in China, the chloroacetic production technique of aniline is adopted in the indigo production of China at present always, and production method mainly comprises condensation reaction, replacement(metathesis)reaction and alkali fusion oxidizing reaction three parts, its technical process such as accompanying drawing 2 successively.

The flow process that can find out indigo production from schema is longer, especially in the process of making intermediate phenylglycocoll potassium, contain condensed mother liquor in the waste water that is produced and molysite washing lotion amount is big and concentration is high that (COD is at 2500-3000mg/L, produce one ton and indigoly will discharge 300 tons of waste water) waste residue (iron mud) is also more difficult in addition, influence environmental protection, also restricted the development of manufacturing enterprise.

Summary of the invention:

The object of the present invention is to provide a kind of improved indigo production method, it can overcome some shortcomings of the prior art.

Technical scheme of the present invention is achieved in that indigo production method, it mainly comprises condensation reaction, hydrolysis reaction and alkali fusion oxidizing reaction, it is characterized in that: is 1 with aniline and hydroxyacetonitrile with mol ratio: 0.9-1: 1.2 metering is placed in the condensation reactor, under 60-105 degree Celsius, react, finish through reaction in 2-8 hour, again reaction mass is all put into hydrolysis reactor, and potassium hydroxide put into hydrolysis reactor with the equal mol ratio of aniline, seething with excitement and the reaction that is hydrolyzed under the backflow is being arranged, and will react the ammonia of being discharged and adopt acid to absorb, till in hydrolysis reactor, no longer discharging ammonia, at last the reaction mass that obtains is concentrated, drying obtains white, yellowish powder or flap phenylglycocoll potassium enter the alkali fusion oxidizing reaction with this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide again.

The present invention is to the condensation reaction in the indigo production, hydrolysis reaction has been done substantial improvement, solved the wastewater problem in the indigo manufacturing enterprise, especially in the process of producing indigo intermediate phenylglycocoll potassium, there is not waste water to discharge, help environmental protection, next has reduced raw-material cost, only phenylglycocoll potassium will reduce raw materials cost about 20%, the 3rd also reduces significantly on energy consumption, the comparable original technology of phenylglycocoll potassium that adopts present method to produce cuts down the consumption of energy more than 40%, simplified production process in addition, saved condensation and the filtration in the hydrolysis reaction and the washing of prior art, and made the indigo coloured light of producing purer.

Description of drawings:

Fig. 1 is a schematic flow sheet of the present invention

Fig. 2 is the schematic flow sheet of prior art

Embodiment:

The invention will be further described and provide embodiment below in conjunction with accompanying drawing.

The present invention mainly comprises condensation reaction, hydrolysis reaction and alkali fusion oxidizing reaction successively, and the reaction principle of condensation reaction, hydrolysis reaction is:

The present invention is different from prior art and is: is 1 with aniline and hydroxyacetonitrile with mol ratio: 0.9-1: 1.2 metering is placed in the condensation reactor, under 60-105 degree Celsius, react, finish through reaction in 2-8 hour, again reaction mass is all put into hydrolysis reactor, and potassium hydroxide put into hydrolysis reactor with the equal mol ratio of aniline, seething with excitement and the reaction that is hydrolyzed under the backflow is being arranged, and will react the ammonia of being discharged and adopt acid to absorb, till in hydrolysis reactor, no longer discharging ammonia, at last the reaction mass that obtains is concentrated, drying obtains white, yellowish powder or flap phenylglycocoll potassium enter the alkali fusion oxidizing reaction with this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide again.Adopting scale tank in the enforcement is 1 with aniline and hydroxyacetonitrile with mol ratio: 0.9-1: 1.2 metering is placed in the condensation reactor, under 60-105 degree Celsius, react, finish through reaction in 2-8 hour, again the reaction mass of aniline and hydroxyacetonitrile is all put into hydrolysis reactor, and potassium hydroxide slowly put into hydrolysis reactor with the equal mol ratio of aniline, seething with excitement and the reaction that is hydrolyzed under the backflow is being arranged, and will react the ammonia of being discharged and adopt acid to absorb, described acid is dilute sulphuric acid, dilute hydrochloric acid, dilute phosphoric acid or acetic acid, till in hydrolysis reactor, no longer discharging ammonia, at last the reaction mass that obtains is concentrated, drying obtains white, yellowish powder or flap phenylglycocoll potassium, again this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide are entered the alkali fusion oxidizing reaction, same as the prior art about the alkali fusion oxidizing reaction, be not described specifically at this.

Embodiment 1

Is that 1: 0.9 metering is placed in the condensation reactor with aniline and hydroxyacetonitrile with mol ratio, reaction under 65 degree Celsius, finish through reaction in 5 hours, again reaction mass is all put into hydrolysis reactor, and the mol ratio that potassium hydroxide and aniline is equal is put into hydrolysis reactor, seething with excitement and the reaction that is hydrolyzed under the backflow is being arranged, and will react the ammonia of being discharged and adopt dilute sulphuric acid to absorb, till in hydrolysis reactor, no longer discharging ammonia, at last the reaction mass that obtains is concentrated, drying obtains white powder phenylglycocoll potassium, again this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide are entered the alkali fusion oxidizing reaction, same as the prior art about the alkali fusion oxidizing reaction, be not described specifically at this, below

Embodiment no longer illustrates.

Embodiment 2

Adopting scale tank is that 1: 1 metering is placed in the condensation reactor with aniline and hydroxyacetonitrile with mol ratio, reaction under 85 degree Celsius, finish through reaction in 4 hours, again the reaction mass of aniline and hydroxyacetonitrile is all put into hydrolysis reactor, and potassium hydroxide slowly put into hydrolysis reactor with the equal mol ratio of aniline, seething with excitement and the reaction that is hydrolyzed under the backflow is being arranged, and will react the ammonia of being discharged and adopt dilute hydrochloric acid to absorb, till in hydrolysis reactor, no longer discharging ammonia, at last the reaction mass that obtains is concentrated, drying obtains yellowish Powdered phenylglycocoll potassium, again this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide is entered the alkali fusion oxidizing reaction.

Embodiment 3

Adopting scale tank is that 1: 1 metering is placed in the condensation reactor with aniline and hydroxyacetonitrile with mol ratio, reaction under 85 degree Celsius, finish through reaction in 4 hours, again the reaction mass of aniline and hydroxyacetonitrile is all put into hydrolysis reactor, and potassium hydroxide slowly put into hydrolysis reactor with the equal mol ratio of aniline, seething with excitement and the reaction that is hydrolyzed under the backflow is being arranged, and will react the ammonia of being discharged and adopt dilute phosphoric acid to absorb, till in hydrolysis reactor, no longer discharging ammonia, at last the reaction mass that obtains is concentrated, drying obtains yellowish sheet phenylglycocoll potassium, again this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide is entered the alkali fusion oxidizing reaction.

Embodiment 4

Adopting scale tank is that 1: 1 metering is placed in the condensation reactor with aniline and hydroxyacetonitrile with mol ratio, reaction under 85 degree Celsius, finish through reaction in 4 hours, again the reaction mass of aniline and hydroxyacetonitrile is all put into hydrolysis reactor, and potassium hydroxide slowly put into hydrolysis reactor with the equal mol ratio of aniline, seething with excitement and the reaction that is hydrolyzed under the backflow is being arranged, and will react the ammonia of being discharged and adopt acetic acid to absorb, till in hydrolysis reactor, no longer discharging ammonia, at last the reaction mass that obtains is concentrated, drying obtains the sheet phenylglycocoll potassium of white, again this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide is entered the alkali fusion oxidizing reaction.

Embodiment 5

At normal temperatures, with 410 kilograms of content 99.6% aniline, after the scale tank metering, put into 3000 liter condensation reaction pots, and under agitation be with 500 kilograms of content 50.3% hydroxyacetonitrile through scale tank metering back slow adding condensation reaction pot, the reinforced time is 30 minutes, this moment, displays temperature was 25 degree Celsius, behind reinforced the finishing with 1600 kilograms of disposable adding reactors of tap water, slowly open the steam valve heating then, when temperature reaches Celsius 65 when spending, valve turns off steam, stop heating, and between 60-65 degree Celsius, be incubated 1.5 hours, open steam valve again and be heated to 100, insulation 2 hours are being arranged under the backflow, condensation reaction finishes, stop heating, again reaction mass is all put into the hydrolysis reaction pot of 4000 liters, add 500 kilograms of tap water then, and allow it be cooled to 50 degree Celsius, be that 48.2% liquid potassium hydroxide slowly adds the hydrolysis reaction pot again with 510 kilograms of content, open steam valve then, begin heating, along with the carrying out of reaction, temperature constantly rises, outlet temperature reaches 103 degree Celsius, and reaction finishes, and the reaction times is 4.5 hours, and will reacting the ammonia of being discharged, to adopt content be that 20% dilute sulphuric acid absorbs into the sulphur ammonium, after hydrolysis reaction finishes, with material (phenylglycocoll potassium solution) after filtering, evaporation concentration, drying gets white plates phenylglycocoll potassium then, again this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide is entered the alkali fusion oxidizing reaction.

Embodiment 6

At normal temperatures, it with 684 kilograms of content 50.1% hydroxyacetonitrile, after the scale tank metering, put into 4000 liter condensation reaction pots, adding 1800 kilograms of tap water then stirred 15 minutes, under agitation be that 98.9% aniline is after stirring 15 minutes with 530 kilograms of content, opening steam valve slowly heats, when temperature reaches Celsius 60 when spending, insulation is 2 hours between 50-60 degree Celsius, open steam valve again and be heated to 85 degree Celsius, insulation 5 hours are being arranged under the backflow, condensation reaction finishes, again reaction mass is all put into the hydrolysis reaction pot of 6000 liters, add 800 kilograms of tap water then, and allow it be cooled to 60 degree Celsius, be that 48.5% liquid potassium hydroxide slowly adds the hydrolysis reaction pot again with 658 kilograms of content, open steam valve then, begin heating, carrying out along with reaction, temperature constantly rises, outlet temperature reaches 102 degree Celsius, reaction finishes, reaction times is 6 hours, and will reacting the ammonia of being discharged, to adopt content be that 30% dilute hydrochloric acid absorbs into ammonium chloride, after hydrolysis reaction finishes, with reaction mass (phenylglycocoll potassium solution) after filtering, evaporation concentration, drying gets white powdery phenylglycocoll potassium then, again this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide is entered the alkali fusion oxidizing reaction.

Claims (3)

1, indigo production method, it mainly comprises condensation reaction successively, hydrolysis reaction and alkali fusion oxidizing reaction, it is characterized in that: is 1 with aniline and hydroxyacetonitrile with mol ratio: 0.9-1: 1.2 metering is placed in the condensation reactor, under 60-105 degree Celsius, react, finish through reaction in 2-8 hour, again reaction mass is all put into hydrolysis reactor, and with potassium hydroxide with aniline 1: 0.9-1: 1.2 mol ratios are put into hydrolysis reactor, seething with excitement and the reaction that is hydrolyzed under the backflow is being arranged, and will react the ammonia of being discharged and adopt acid to absorb, till in hydrolysis reactor, no longer discharging ammonia, at last the reaction mass that obtains is concentrated, drying obtains white, yellowish powder or flap phenylglycocoll potassium enter the alkali fusion oxidizing reaction with this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide again.

2, by the described indigo production method of claim 1, it is characterized in that: adopting scale tank is 1 with aniline and hydroxyacetonitrile with mol ratio: 0.9-1: 1.2 metering is placed in the condensation reactor, under 60-105 degree Celsius, react, finish through reaction in 2-8 hour, again the reaction mass of aniline and hydroxyacetonitrile is all put into hydrolysis reactor, and with potassium hydroxide with aniline 1: 0.9-1: 1.2 mol ratios are slowly put into hydrolysis reactor, seething with excitement and the reaction that is hydrolyzed under the backflow is being arranged, and will react the ammonia of being discharged and adopt acid to absorb, till in hydrolysis reactor, no longer discharging ammonia, at last the reaction mass that obtains is concentrated, drying obtains white, yellowish powder or flap phenylglycocoll potassium enter the oxidation of alkali fusion oxidizing reaction with this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide again.

3, by claim 1 or 2 described indigo production methods, it is characterized in that: described acid is dilute sulphuric acid, dilute hydrochloric acid, dilute phosphoric acid or acetic acid.