CN101412686A - Method for preparing 2,7-naphthalenedisulfonate with reaction mother liquor for producing 1,6-naphthalene disulfonic acid - Google Patents
Method for preparing 2,7-naphthalenedisulfonate with reaction mother liquor for producing 1,6-naphthalene disulfonic acid Download PDFInfo
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- CN101412686A CN101412686A CNA2008102352419A CN200810235241A CN101412686A CN 101412686 A CN101412686 A CN 101412686A CN A2008102352419 A CNA2008102352419 A CN A2008102352419A CN 200810235241 A CN200810235241 A CN 200810235241A CN 101412686 A CN101412686 A CN 101412686A
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Abstract
The invention discloses a method for preparing 2, 7-naphthalenedisulfonic acid disodium salt from reaction mother solution of producing 1, 6-naphthalenedisulfonic acid. The method comprises the following steps: 1. concentrating the mother solution of the 1, 6-naphthalenedisulfonic acid under reduced pressure ; 2. adding sulfuric acid, refined naphthalene and catalysts into the concentrated solution to react; 3. cooling temperature of the reaction solution 100 DEG C below zero, adding sodium chloride aqueous solution, sodium chloride and sodium sulfate into the cooled reaction solution, stirring the mixed solution, and maintaining system negative pressure to remove chlorine hydride in the solution; 4. insulating and filtering liquid-solid mixture to obtain crude 2, 6-naphthalenedisulfonic acid disodium salt solid and filtrate I; 5. insulating, washing and filtering the obtained crude 2, 6-naphthalenedisulfonic acid disodium salt solid by sodium sulfate solution to obtain the refined 2, 6-naphthalenedisulfonic acid disodium salt solid and filtrate II; and 6. mixing the filtrate I and the filtrate II, and adding aqueous sodium chloride into the mixed filtrate for crystallization to obtain a product of the 2, 7-naphthalenedisulfonic acid disodium salt. The method has the advantages that the method is advanced and simple, and uses waste solution, protects the environment, and has obvious economic and social benefits.
Description
Technical field
The present invention relates to a kind of utilization and produce 1, the reaction mother liquor preparation 2 of 6-naphthalene disulfonic acid, the method for 7-naphthalene disulfonate, it belongs to the preparation of napadisilate, belongs to more precisely to produce 1, the comprehensive utilization of the reaction mother liquor of 6-naphthalene disulfonic acid.
Background technology
1, the 6-dihydroxy naphthlene is the important intermediate of dyestuffs industries, and it and multiple diazo component coupling can obtain a series of acid mordant dyes, are mainly used in silk, cashmere and wool industry.1, the 6-dihydroxy naphthlene is by 1, and 6-naphthalene disulfonate and sodium hydroxide make through the constant-pressure and high-temperature alkali fusion.And 1, the synthetic of 6-naphthalene disulfonate is earlier refined naphthalene to be obtained being rich in 1 with the two step sulfonation of 20% oleum after the step sulfonation again in the vitriol oil of 150～155 ℃ of high temperature, the sulfonated liquid of 6-naphthalene disulfonic acid, this sulfonated liquid is diluted to certain acidity with water and separates out highly purified 1, the 6-naphthalene disulfonic acid, with 1,6-naphthalene disulfonic acid and sodium-chlor reaction obtain 1, the 6-naphthalene disulfonate again.Sulfuric acid is solvent in two step sulfonation process of naphthalene, is again sulphonating agent, so the vitriolic large usage quantity.1,6-naphthalene disulfonic acid Crystallization Separation, its yield is 55～60% of a theoretical yield only, still contains a large amount of sulfonated products and sulfuric acid in the mother liquor after the filtration, contains the sulfuric acid of 250～400kg naphthene sulfonic acid and 25～45% (massfraction) in 1 ton of mother liquor approximately.Manufacturer handles this mother liquor as waste liquid at present.This has not only wasted a large amount of sulfuric acid and sulfonated products, causes too much waste liquid to handle, and causes bigger economical load to enterprise.Therefore how to fully utilize 1,6 one naphthalene disulfonic acid mother liquor, become the problem that present urgent need solves, adapted to current environmental protection requirement.
2, the 7-naphthalene disulfonate is the important intermediate of preparation dyestuff, pigment dyestuff, medicine and agrochemicals, along with deepening continuously of research, and 2, the purposes of 7-naphthalene disulfonate is more and more extensive.Studies show that in the sulfonation reaction system of naphthalene, under different sulfuric acid concentrations, temperature of reaction and suitable catalyst action, sulfonation reaction is a reversible.Increasing of temperature of reaction carries out intramolecule easily and resets, and becomes other isomer.Given this, under appropriate reaction conditions, make 1,1 in the 6-naphthalene disulfonic acid mother liquor, 5-naphthalene disulfonic acid, 1,6-naphthalene disulfonic acid and single sulfonic acid are converted into 2,6-naphthalene disulfonic acid and 2,7-naphthalene disulfonic acid, and then prepare and have 2 of industrial value, the 7-naphthalene disulfonate then becomes comprehensive utilization 1, the new way of 6-naphthalene disulfonic acid mother liquor.This has not only recycled a large amount of sulfuric acid and sulfonated products, has reduced the waste of sewage disposal expense and other resource again, has remarkable economic efficiency and social benefit.And relevant both at home and abroad comprehensive utilization 1,6-naphthalene disulfonic acid mother liquor preparation 2, the technology of 7-naphthalene disulfonate is not seen reported in literature as yet.
Summary of the invention
The objective of the invention is to avoid above-mentioned weak point of the prior art, produce 1 and disclose a kind of utilization, the reaction mother liquor preparation 2 of 6-naphthalene disulfonic acid, the method of 7-naphthalene disulfonate, for making full use of above-described 1, sulfuric acid in the 6-naphthalene disulfonic acid mother liquor and a large amount of naphthene sulfonic acid prepare 2 by intramolecular rearrangement, the 7-naphthalene disulfonate.That is to say, be that the sulfonation by naphthalene prepares 1 simultaneously, 6-naphthalene disulfonic acid and 2, and the method for 7-naphthalene disulfonate to satisfy market and needs of society, reduces environmental pollution, increases economic efficiency.
Technical scheme of the present invention is as follows:
A kind of utilization produces 1, the reaction mother liquor preparation 2 of 6-naphthalene disulfonic acid, and the method for 7-naphthalene disulfonate, it is made up of the following step basically:
(1) concentrate 1,6-naphthalene disulfonic acid mother liquor concentrating under reduced pressure, vacuum tightness 0.08～0.095atm, along with the rising of mother liquor sulfuric acid concentration, its temperature also constantly rises, till temperature is raised to temperature of reaction;
(2) reaction adds the vitriol oil of 0.2～0.6 times (mass ratio) and the refined naphthalene of 0.07～0.3 times (mass ratio) in the concentrated solution of step (1), adds appropriate amount of catalysts simultaneously, under stirring state temperature is elevated to temperature of reaction, the reaction regular hour;
(3) 2, after the crystallization reaction of 6-naphthalene disulfonate finishes, system temperature is dropped to below 100 ℃, in reaction system, add a certain amount of sodium chloride aqueous solution, after stirring 30 minutes under 95 ℃, add a certain amount of sodium-chlor and sodium sulfate again, keep 95 ℃ of temperature, stirred 2 hours, and keep the system negative pressure, to take out hydrogenchloride wherein;
(4) filter (3) liquid-solid mixture insulation filtered, obtain thick 2,6-naphthalene disulfonate solid and filtrate (I);
(5) washing and filter with (4) step obtain thick 2,6-naphthalene disulfonate solid is with 20% metabisulfite solution insulation washing 30 minutes, again in 95 ℃ of filtrations, obtains smartly 2,6-naphthalene disulfonate solid gets filtrate (II) simultaneously;
The crystallization of (6) 2,7-naphthalene disulfonates with filtrate (I) and filtrate (II) merge filtrate (III), control wherein 2, the content of 6-naphthalene disulfonate＜5% (liquid-phase chromatographic analysis).In filtrate (III), add an amount of water and sodium-chlor, slowly cooling under room temperature, static crystallization obtains 2,7-naphthalene disulfonate product.
Described 1, the component and the weight percentage of 6-naphthalene disulfonic acid mother liquor are: naphthene sulfonic acid 5～60%, sulfuric acid 10～80%, water 15～75%.
Described temperature of reaction is 160～220 ℃, is preferably 170～180 ℃.
The described reaction times is 1～8 hour, is preferably 2～5 hours.
Described catalyzer is conventional strongly acidic catalyst, can be liquid catalyst, also can be solid catalyst.
The present invention produces 1 to utilize, the reaction mother liquor preparation 2 of 6-naphthalene disulfonic acid, and the 7-naphthalene disulfonate is 2, and the production of 7-naphthalene disulfonate product provides a new approach, is 1 simultaneously, and the comprehensive utilization of the reaction mother liquor of 6-naphthalene disulfonic acid provides new thinking.Characteristics such as with present production 2, the technology of 7-naphthalene disulfonate is compared, and this method production cost is low, less investment, production intensity big and the process three waste discharge is few, 2, the comprehensive production cost of 7-naphthalene disulfonate product reduces significantly.Therefore this technology has remarkable economic efficiency, social benefit and great application and popularization value.
Description of drawings
Fig. 1 is a process flow diagram of the present invention.
Embodiment
To help to understand the present invention by following embodiment, but not limit content of the present invention.
Embodiment one
Take by weighing 300 grams 1,6-naphthalene disulfonic acid mother liquor, its quality group becomes: naphthene sulfonic acid, 24.23%; Sulfuric acid, 34.56%; Water, 41.21.This mother liquor concentrating under reduced pressure to 175 ℃ under vacuum tightness 0.09atm.In concentrated solution, add sulfuric acid, 38 gram refined naphthalenes and the 0.08 gram catalyzer of 56 grams 98% (massfraction), under stirring state, temperature is elevated to 175 ℃, reacted 2.5 hours, obtain containing 2,6-naphthalene disulfonic acid and 2, the sulfonated liquid of 7-naphthalene disulfonic acid.Through liquid-phase chromatographic analysis, 2, the percentage composition of 6-naphthalene disulfonic acid is 24.62%, 2, the percentage composition of 7-naphthalene disulfonic acid is 61.34%.
After reaction finishes, system temperature is dropped to 96 ℃, adding concentration is 9.46% sodium chloride aqueous solution 351 grams in reaction system, after stirring 30 minutes under 95 ℃, add 30 gram sodium-chlor and 33 gram sodium sulfate again, keep 95 ℃ of temperature, stirred 2 hours, and keep the system negative pressure, to take out hydrogenchloride wherein.Insulation is filtered slightly 2 then, 6-naphthalene disulfonate solid and filtrate (I).With thick 2,6-naphthalene disulfonate solid is with 25% metabisulfite solution 88 gram insulation washings 30 minutes, again in 95 ℃ of filtrations, obtain smart 2,6-naphthalene disulfonate solid, liquid-phase chromatographic analysis, 2,6-naphthalene disulfonate solid purity is 92.2%; Simultaneously filtrate (II), with filtrate (I) and filtrate (II) merge filtrate (III).In the sulfonated bodies of filtrate (III), 2, the percentage composition of 6-naphthalene disulfonic acid is 3.8%, 2, the percentage composition of 7-naphthalene disulfonic acid is 89.41%.
Add 73 gram water and 20 gram NaCl in filtrate (III), temperature is slowly dropped to room temperature, static crystallization obtains 2,7-naphthalene disulfonate product 84.3 grams (dry product), and its purity is 98.3%.In refined naphthalene, 2, folding hundred yields of 7-naphthalene disulfonate are 81.21%.
Embodiment two
Take by weighing 300 grams 1,6-naphthalene disulfonic acid mother liquor, its quality is formed identical with embodiment one.This mother liquor concentrating under reduced pressure to 175 ℃ under vacuum tightness 0.093atm.In concentrated solution, add sulfuric acid, 38 gram refined naphthalenes and the 0.08 gram catalyzer of 56 grams 98% (massfraction), under stirring state, temperature is elevated to 175 ℃, reacted 3 hours, obtain containing 2,6-naphthalene disulfonic acid and 2, the sulfonated liquid of 7-naphthalene disulfonic acid.Through liquid-phase chromatographic analysis, 2, the percentage composition of 6-naphthalene disulfonic acid is 25.43%, 2, the percentage composition of 7-naphthalene disulfonic acid is 66.22%.
After reaction finishes, system temperature is dropped to 96 ℃, adding concentration is 9.46% sodium chloride aqueous solution 351 grams in reaction system, after stirring 30 minutes under 95 ℃, add 30 gram sodium-chlor and 33 gram sodium sulfate again, keep 95 ℃ of temperature, stirred 2 hours, and keep the system negative pressure, to take out hydrogenchloride wherein.Insulation is filtered slightly 2 then, 6-naphthalene disulfonate solid and filtrate (I).With thick 2,6-naphthalene disulfonate solid is with 25% metabisulfite solution 88 gram insulation washings 30 minutes, again in 95 ℃ of filtrations, obtain smart 2,6-naphthalene disulfonate solid, liquid-phase chromatographic analysis, 2,6-naphthalene disulfonate solid purity is 89.7%; Simultaneously filtrate (II), with filtrate (I) and filtrate (II) merge filtrate (III).In the sulfonated bodies of filtrate (III), 2, the percentage composition of 6-naphthalene disulfonic acid is 4.1%, 2, the percentage composition of 7-naphthalene disulfonic acid is 88.35%.
Add 73 gram water and 20 gram NaCl in filtrate (III), temperature is slowly dropped to room temperature, static crystallization obtains 2,7-naphthalene disulfonate product 84.6 grams (dry product), and its purity is 98.1%.In refined naphthalene, 2, folding hundred yields of 7-naphthalene disulfonate are 80.96%.
Embodiment three
Take by weighing 300 grams 1,6-naphthalene disulfonic acid mother liquor, its quality is formed identical with embodiment one.This mother liquor concentrating under reduced pressure to 180 ℃ under vacuum tightness 0.085atm.In concentrated solution, add sulfuric acid, 27 gram refined naphthalenes and the 0.08 gram catalyzer of 40 grams 98% (massfraction), under stirring state, temperature is elevated to 180 ℃, reacted 2.5 hours, obtain containing 2,6-naphthalene disulfonic acid and 2, the sulfonated liquid of 7-naphthalene disulfonic acid.Through liquid-phase chromatographic analysis, 2, the percentage composition of 6-naphthalene disulfonic acid is 23.26%, 2, the percentage composition of 7-naphthalene disulfonic acid is 64.17%.
After reaction finishes, system temperature is dropped to 96 ℃, adding concentration is 9.46% sodium chloride aqueous solution 351 grams in reaction system, after stirring 30 minutes under 95 ℃, add 27 gram sodium-chlor and 28 gram sodium sulfate again, keep 95 ℃ of temperature, stirred 2 hours, and keep the system negative pressure, to take out hydrogenchloride wherein.Insulation is filtered slightly 2 then, 6-naphthalene disulfonate solid and filtrate (I).With thick 2,6-naphthalene disulfonate solid is with 25% metabisulfite solution 79 gram insulation washings 30 minutes, again in 95 ℃ of filtrations, obtain smart 2,6-naphthalene disulfonate solid, liquid-phase chromatographic analysis, 2,6-naphthalene disulfonate solid purity is 91.1%; Simultaneously filtrate (II), with filtrate (I) and filtrate (II) merge filtrate (III).In the sulfonated bodies of filtrate (III), 2, the percentage composition of 6-naphthalene disulfonic acid is 3.81%, 2, the percentage composition of 7-naphthalene disulfonic acid is 88.84%.
Add 65 gram water and 14 gram NaCl in filtrate (III), temperature is slowly dropped to room temperature, static crystallization obtains 2,7-naphthalene disulfonate product 59.6 grams (dry product), and its purity is 98.4%.In refined naphthalene, 2, folding hundred yields of 7-naphthalene disulfonate are 81.94%.
Embodiment four
Take by weighing 300 grams 1,6-naphthalene disulfonic acid mother liquor, its quality group becomes: naphthene sulfonic acid, 26.42%; Sulfuric acid, 37.41%; Water, 36.17%.This mother liquor concentrating under reduced pressure to 175 ℃ under vacuum tightness 0.091atm.In concentrated solution, add sulfuric acid, 37 gram refined naphthalenes and the 0.08 gram catalyzer of 56 grams 98% (massfraction), under stirring state, temperature is elevated to 175 ℃, reacted 2.5 hours, obtain containing 2,6-naphthalene disulfonic acid and 2, the sulfonated liquid of 7-naphthalene disulfonic acid.Through liquid-phase chromatographic analysis, 2, the percentage composition of 6-naphthalene disulfonic acid is 25.12%, 2, the percentage composition of 7-naphthalene disulfonic acid is 65.47%.
After reaction finishes, system temperature is dropped to 96 ℃, adding concentration is 9.46% sodium chloride aqueous solution 351 grams in reaction system, after stirring 30 minutes under 95 ℃, add 30 gram sodium-chlor and 33 gram sodium sulfate again, keep 95 ℃ of temperature, stirred 2 hours, and keep the system negative pressure, to take out hydrogenchloride wherein.Insulation is filtered slightly 2 then, 6-naphthalene disulfonate solid and filtrate (I).With thick 2,6-naphthalene disulfonate solid is with 25% metabisulfite solution 88 gram insulation washings 30 minutes, again in 95 ℃ of filtrations, obtain smart 2,6-naphthalene disulfonate solid, liquid-phase chromatographic analysis, 2,6-naphthalene disulfonate solid purity is 89.1%; Simultaneously filtrate (II), with filtrate (I) and filtrate (II) merge filtrate (III).In the sulfonated bodies of filtrate (III), 2, the percentage composition of 6-naphthalene disulfonic acid is 4.06%, 2, the percentage composition of 7-naphthalene disulfonic acid is 89.11%.
Add 73 gram water and 20 gram NaCl in filtrate (III), temperature is slowly dropped to room temperature, static crystallization obtains 2,7-naphthalene disulfonate product 79.6 grams (dry product), and its purity is 98.3%.In refined naphthalene, 2, folding hundred yields of 7-naphthalene disulfonate are 80.18%.
Claims (5)
1, a kind of utilization produces 1, the reaction mother liquor preparation 2 of 6-naphthalene disulfonic acid, and the method for 7-naphthalene disulfonate is characterized in that comprising the steps:
(1) with 1,6-naphthalene disulfonic acid mother liquor concentrating under reduced pressure;
(2) adding mass ratio in concentrated solution is the refined naphthalene that 0.2～0.6 times the vitriol oil and mass ratio are 0.07～0.3 times, adds appropriate amount of catalysts simultaneously, under stirring state temperature is elevated to temperature of reaction, the reaction regular hour;
(3) reacting liquid temperature is dropped to below 100 ℃, add a certain amount of sodium chloride aqueous solution, after stirring 30 minutes under 95 ℃, add a certain amount of sodium-chlor and sodium sulfate again, keep 95 ℃ of temperature, stirred 2 hours, and keep the system negative pressure, to take out hydrogenchloride wherein;
(4) insulation of (3) liquid-solid mixture is filtered, obtain thick 2,6-naphthalene disulfonate solid and filtrate I;
What (5) (4) step was obtained is thick 2, and 6-naphthalene disulfonate solid is with 20% metabisulfite solution insulation washing 30 minutes, again in 95 ℃ of filtrations, obtains smartly 2, and 6-naphthalene disulfonate solid gets filtrate II simultaneously;
(6) filtrate I and filtrate II are merged filtrate II I, control wherein 2, the content of 6-naphthalene disulfonate＜5% adds an amount of water in filtrate II I, slowly cooling under room temperature, static crystallization obtains 2,7-naphthalene disulfonate product.
2, utilization according to claim 1 produces 1, the reaction mother liquor preparation 2 of 6-naphthalene disulfonic acid, and the method for 7-naphthalene disulfonate is characterized in that describedly 1, the component and the weight percentage of 6-naphthalene disulfonic acid mother liquor are:
Naphthene sulfonic acid 5～60%
Sulfuric acid 10～80%
Water 15～75%
3, utilization according to claim 1 produces 1, the reaction mother liquor preparation 2 of 6-naphthalene disulfonic acid, the method for 7-naphthalene disulfonate, it is characterized in that described 1, the vacuum tightness of 6-naphthalene disulfonic acid mother liquor concentrating under reduced pressure is 0.08～0.095atm, is concentrated to 160～220 ℃, is preferably 170～180 ℃.
4, utilization according to claim 1 produces 1, the reaction mother liquor preparation 2 of 6-naphthalene disulfonic acid, and the method for 7-naphthalene disulfonate is characterized in that described temperature of reaction is 160～220 ℃, is preferably 170～180 ℃.
5, utilization according to claim 1 produces 1, the reaction mother liquor preparation 2 of 6-naphthalene disulfonic acid, and the method for 7-naphthalene disulfonate is characterized in that the described reaction times is 1～8 hour, is preferably 2～5 hours.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101723859B (en) * | 2009-12-08 | 2012-09-05 | 南通柏盛化工有限公司 | Method for isomerizing 2,6-naphthalene disulfonic acid into 2,7-naphthalene disulfonic acid |
| CN102993061A (en) * | 2012-07-30 | 2013-03-27 | 枣庄市泰瑞精细化工有限公司 | Preparation method of 2,7-sodium naphthalenedisulfonate product using transforming production of 1,6-naphthalenedisulfonic mother liquid |
| CN102993060A (en) * | 2012-07-30 | 2013-03-27 | 枣庄市泰瑞精细化工有限公司 | Preparation method of 1,6-naphthalenedisulfonic acid disodium salt |
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2008
- 2008-11-12 CN CNA2008102352419A patent/CN101412686A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101723859B (en) * | 2009-12-08 | 2012-09-05 | 南通柏盛化工有限公司 | Method for isomerizing 2,6-naphthalene disulfonic acid into 2,7-naphthalene disulfonic acid |
| CN102993061A (en) * | 2012-07-30 | 2013-03-27 | 枣庄市泰瑞精细化工有限公司 | Preparation method of 2,7-sodium naphthalenedisulfonate product using transforming production of 1,6-naphthalenedisulfonic mother liquid |
| CN102993060A (en) * | 2012-07-30 | 2013-03-27 | 枣庄市泰瑞精细化工有限公司 | Preparation method of 1,6-naphthalenedisulfonic acid disodium salt |
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Application publication date: 20090422 |