CN1465625A - Method for producing indigo - Google Patents

Abstract

The production method of indigo incldues the following steps: placing aniline and hydroxy-acetonitrile into a condensation reactor according to the mole ratio of 1:0.9-1:1.2, reacting for 2-8 hr. at 60-105 deg.C; placing all the reactants into separator to make stratification by standing still; placing lower layer oily material into crystallizing tank to make solidification, and when the aniline acetonitrile content is up to above 90%, directly adding the above-mentioned material into the hydrolysis reactor, placing the supernatnat fluid in the separator into the condensation reactor; placing the liquid potassium and aniline acetonitrile into the reactor according to the mole ratio of 1:0.9-1:1.2, under the condition of boiling and refluxing making hydrolysis reaction, using acid adsorb the ammonia gas discharged by reaction.

Description

A kind of indigo production method

Technical field:

The utility model belongs to the technical field of chemical dyestuff, and 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 the intermediate phenylglycocoll potassium of making, contain condensed mother liquor in the waste water that is produced and the molysite amount of filtrate 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 (irony) 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 a kind of 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 separator and carry out static layering, layer oily matter in the separator is put into crystallizer tank to be solidified, reach more than 90% to the aniline ethane nitrile content and can directly drop into hydrolysis reactor, be placed into the supernatant liquid in the separator in the condensation reactor again; Is 1 with liquid potassium and aniline acetonitrile with mol ratio: 0.9-1: reactor is put in 1.2 metering, 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, again this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide is entered the alkali fusion oxidizing reaction.

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 separator and carry out static layering, layer oily matter in the separator is put into crystallizer tank to be solidified, reach more than 90% to the aniline ethane nitrile content and can directly drop into hydrolysis reactor, be placed into the supernatant liquid in the separator in the condensation reactor again; Is 1 with liquid potassium and aniline acetonitrile with mol ratio: 0.9-1: reactor is put in 1.2 metering, 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, again this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide is entered the alkali fusion oxidizing reaction.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 reaction mass is all put into separator and carry out static layering, layer oily matter in the separator is put into crystallizer tank to be solidified, reach more than 90% to the aniline ethane nitrile content and can directly drop into hydrolysis reactor, be placed into the supernatant liquid in the separator in the condensation reactor again; Adopting scale tank is 1 with liquid potassium and aniline acetonitrile with mol ratio: 0.9-1: hydrolysis reactor is put in 1.2 metering, 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 enter the alkali fusion oxidizing reaction with this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide again.

Embodiment 1

Is that 1: 0.95 metering is placed in the condensation reactor with aniline and hydroxyacetonitrile with mol ratio, under 65-101 degree Celsius, react, finish through reaction in 7 hours, again reaction mass is all put into separator and carry out static layering, layer oily matter in the separator is put into crystallizer tank to be solidified, reach more than 92% to the aniline ethane nitrile content and can directly drop into hydrolysis reactor, be placed into the supernatant liquid in the separator in the condensation reactor again; Is that reactor is put in 1: 0.95 metering with liquid potassium and aniline acetonitrile with mol ratio, seething with excitement and the reaction that is hydrolyzed under the backflow is being arranged, and will reacting the ammonia of being discharged, to adopt concentration be that 20% dilute sulphuric acid absorbs, 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 2

Adopting scale tank is that 1: 1.1 metering is placed in the condensation reactor with aniline and hydroxyacetonitrile with mol ratio, under 70-101 degree Celsius, react, finish through reaction in 6 hours, again reaction mass is all put into separator and carry out static layering, layer oily matter in the separator is put into crystallizer tank to be solidified, reach more than 91% to the aniline ethane nitrile content and can directly drop into hydrolysis reactor, be placed into the supernatant liquid in the separator in the condensation reactor again; Adopting scale tank is that hydrolysis reactor is put in 1: 1: 1 metering with liquid potassium and aniline acetonitrile with mol ratio, 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 25% dilute hydrochloric acid absorption, till in hydrolysis reactor, no longer discharging ammonia, at last the reaction mass that obtains is concentrated, drying obtains white plates phenylglycocoll potassium, again this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide is entered the alkali fusion oxidizing reaction.

Embodiment 3

Be 50.1% hydroxyacetonitrile at normal temperatures with 684 kilograms of content, put into 4000 liter condensation reaction pots after metering, add 1800 kilograms of tap water then, stir after 15 minutes that to add 530 kilograms of content be 99.6% aniline, stir after 15 minutes, open steam valve, slowly heating, insulation is 1.5 hours under 55-60 degree Celsius, be warmed up to 85 degree Celsius then, and this temperature insulation 6 hours, condensation reaction finished, and allowed the reaction mass static layering again, static 25 minutes, lower floor's buttery aniline acetonitrile is put into crystallizer tank, break packing into pieces after to be crystallized, metering, supernatant liquid are put into storage tank cooling back as the condensation water that feeds intake; With 837 kilograms of content is the hydrolysis reactor that 94.5% aniline acetonitrile drops into 6000 liters, and add 2000 kilograms tap water, slowly heating, treat that temperature rises to Celsius 50 when spending, begin to stir, rise to Celsius 55 when spending in temperature, with 658 kilograms of content is that 48.5% potassium hydroxide slowly adds hydrolysis reactor, heat temperature raising is to 103 degree Celsius then, and insulation 6 hours are being arranged under the backflow, hydrolysis reaction finishes, and will react the ammonia of being discharged and adopt 30% dilute sulphuric acid to absorb into the sulphur ammonium, till in hydrolysis reactor, no longer discharging ammonia, at last the reaction mass phenylglycocoll potassium that obtains is concentrated, drying obtains white powdery phenylglycocoll potassium, again this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide is entered the alkali fusion oxidizing reaction.

Claims (3)

1, a kind of 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 separator and carry out static layering, layer oily matter in the separator is put into crystallizer tank to be solidified, reach more than 90% to the aniline ethane nitrile content and can directly drop into hydrolysis reactor, be placed into the supernatant liquid in the separator in the condensation reactor again; Is 1 with liquid potassium and aniline acetonitrile with mol ratio: 0.9-1: reactor is put in 1.2 metering, 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, again this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide is entered the alkali fusion oxidizing reaction.

2, by the described a kind of 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 reaction mass is all put into separator and carry out static layering, layer oily matter in the separator is put into crystallizer tank to be solidified, reach more than 90% to the aniline ethane nitrile content and can directly drop into hydrolysis reactor, be placed into the supernatant liquid in the separator in the condensation reactor again; Adopting scale tank is 1 with liquid potassium and aniline acetonitrile with mol ratio: 0.9-1: hydrolysis reactor is put in 1.2 metering, 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, again this phenylglycocoll potassium and sodium hydroxide hydro-oxidation potassium and sodium amide is entered the alkali fusion oxidizing reaction.

3, by claim 1 or 2 described a kind of, it is characterized in that: described acid is dilute sulphuric acid, dilute hydrochloric acid, dilute phosphoric acid or acetic acid.