CN103880602A - Technology for producing hydroquinone by hydrolysis of p-aminophenol through continuous method - Google Patents
Technology for producing hydroquinone by hydrolysis of p-aminophenol through continuous method Download PDFInfo
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- CN103880602A CN103880602A CN201210557199.9A CN201210557199A CN103880602A CN 103880602 A CN103880602 A CN 103880602A CN 201210557199 A CN201210557199 A CN 201210557199A CN 103880602 A CN103880602 A CN 103880602A
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- C07—ORGANIC CHEMISTRY
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- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
- C07C37/01—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by replacing functional groups bound to a six-membered aromatic ring by hydroxy groups, e.g. by hydrolysis
- C07C37/045—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by replacing functional groups bound to a six-membered aromatic ring by hydroxy groups, e.g. by hydrolysis by substitution of a group bound to the ring by nitrogen
- C07C37/05—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by replacing functional groups bound to a six-membered aromatic ring by hydroxy groups, e.g. by hydrolysis by substitution of a group bound to the ring by nitrogen by substitution of a NH2 group
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Abstract
The invention relates to a technology for producing hydroquinone by hydrolysis of p-aminophenol through a continuous method, which takes para aminophenol hydrochloride as a raw material, the para aminophenol hydrochloride is mixed with hydrochloric acid, preheated to 220-240 DEG C, a hydrolysis reaction is carried out for 150-420 minutes in a tower type reactor, after the reaction is finished, a hydrolysis reaction solution overflows from a discharge hatch of the tower type reactor, the hydrolysis reaction solution is subjected to extraction, phase-splitting and desolvation to obtain the hydroquinone crude product. The technology for producing hydroquinone has the advantages of little waste water in a reaction system, continuous production, high production efficiency, high yield and simple technology control.
Description
Technical field
The invention belongs to organic synthesis field, be specifically related to the technique that Resorcinol is produced in a kind of p-aminophenol continuous processing hydrolysis.
Background technology
Resorcinol is a kind of important Organic Chemicals, is the important source material of rubber, medicine, dyestuff, agricultural chemicals and field of food, has larger market demand.External producer generally adopts phenol-hydrogen peroxide hydroxylation method and diisopropylbenzene(DIPB) peroxidation method to produce Resorcinol.Although domestic production ability is larger, be almost to adopt external superseded aniline oxidation style entirely, the method equipment corrosion is serious, and produces a large amount of manganous sulfates, ammonium sulphate waste liquor and iron mud, and environmental pollution is serious, on the verge of being replaced.
P-aminophenol direct hydrolysis is prepared the method for Resorcinol, has raw material sources facility, the simple advantage of technique, and extremely pay attention to, a series of bibliographical informations relevant research.In patent DE2459233, taking the monoammonium sulfate aqueous solution as reaction medium, p-aminophenol direct hydrolysis in the airtight high-pressure stirring still of glass inner-lining is prepared Resorcinol, adopt intermittent type hydrolysis process, this technique main drawback is that p-aminophenol is hydrolyzed the easily a large amount of arborescens products of generation under monoammonium sulfate medium.In patent EP0015876, taking the methanesulfonic aqueous solution as reaction medium, the mol ratio of p-aminophenol and methanesulfonic is 1:1,240 DEG C of temperature of reaction, 3 hours reaction times, content in crude product 81.8%, yield: 72.7%, there is per pass conversion and the lower problem of hydrolysis yield in this technique.In patent JP52057129, JP53002433, JP53012824, JP53063330, p-aminophenol joins sulfuric acid, hydrochloric acid, hydrobromic autoclave confined reaction 3～10 hours, 200～300 DEG C of temperature of reaction, yield: 43.5%～93.7%, same reaction conditions, obtains Resorcinol yield 65.1% and 93.7%.In patent US3862247 and GB1460655, taking the monoammonium sulfate aqueous solution as reaction medium, monoammonium sulfate and p-aminophenol mol ratio are 1.5-4, temperature of reaction 240-280 DEG C, and reaction 2-6 hour, yield, at 58.4-72.7%, is up to 72.7%.
The method that the p-aminophenol direct hydrolysis of having reported is at present prepared Resorcinol mainly faces following three aspects: problem.
(1) produce a large amount of waste water.Because hydrolysis reaction material concentration is low, reaction finishes a large amount of by products of rear generation, causes the waste water can not recycled, produces a large amount of acid-bearing wastewaters.
(2) adopt interrupter method hydrolysis.There is material back-mixing, excessively hydrolysis reaction, reaction preference is poor, side reaction increases problem in interrupter method reaction, easily produces a large amount of tar, blocking pipe.
(3) hydrolysis reaction carries out under high temperature and high pressure, and cold material needs heating, and thermal material needs cooling, and energy consumption is large, and the non-cutting time of intensification and cooling is long, and production efficiency is low.Energy can not get reasonable utilization, and large-scale production is lacked competitiveness.
Summary of the invention
The present invention is directed to the hydrolysis of p-aminophenol interrupter method and produce the problem that in Resorcinol technique, wastewater flow rate is large, production capacity is low and energy consumption is large, propose the technique that Resorcinol is produced in a kind of continuous processing hydrolysis, obtained Resorcinol taking the rodinal aqueous solution as raw material through heating hydrolysis.
Technical solution of the present invention is as follows:
The technique that Resorcinol is produced in a kind of p-aminophenol continuous processing hydrolysis, taking rodinal as raw material, after mixed in hydrochloric acid, be preheated to 220～240 DEG C, hydrolysis reaction 150-420 minute in tower reactor 7, react complete, hydrolysis reaction liquid overflows from tower reactor 7 discharge ports (outlet of tower reactor top), and hydrolysis reaction liquid obtains Resorcinol crude product after extraction, phase-splitting, precipitation.Make the transformation efficiency of rodinal be no more than 60% by controlling temperature of reaction and reaction times
The technique that Resorcinol is produced in p-aminophenol continuous processing hydrolysis of the present invention, adopt device to comprise the material-compound tank (2) for preparing rodinal hydrolysis material, the line mixer (4) of mixed hydrolysis raw material, for interchanger-1(6 that mixing raw material is heated), interchanger-2(5), for the tower reactor (7) of the reaction that is hydrolyzed, for the extraction tower (1) of extracted products, the outlet and interchanger-2(5 of line mixer (4)) material inlet be communicated with, interchanger-2(5) with interchanger-1(6) connect, interchanger-1(6) material outlet be connected with tower reactor (7) top material import, tower reactor (7) discharge port and interchanger-2(5) shell side opening for feed be connected, interchanger-2(5) shell side outlet be connected with extraction tower (1) opening for feed, extraction tower (1) lower part outlet is connected with material-compound tank (2).Interchanger-1(6), interchanger-2(5) be tube and shell heat exchanger, interchanger-1(6) heating medium of shell side adopts thermal oil or other heating mediums, interchanger-2(5) shell side is the hydrolysis reaction liquid from tower reactor (7) discharge port.Tower reactor (7) is popular response device, its outer wall is with heating coil, the blade diameter length ratio of tower reactor (7) discharge port (outlet of tower reactor overflow) is 1:5-15, preferably 1:10, tower includes 3-11 piece traverse baffle, tower reactor (7) discharge port is provided with baffle plate, to prevent the direct outflow reactor of inlet feed unreacted.
Technique of the present invention comprises the steps:
1) by the hydrochloric hydrolysis material of material-compound tank (2) preparation rodinal, form the uniform rodinal aqueous solution through line mixer (4);
2) hydrolysis material of the rodinal preparing is first by interchanger-2(5) tube side enters interchanger-1(6) tube side, at interchanger-1(6) in by heating medium, material is preheating to after 220～240 DEG C, join continuously tower reactor (7) from tower reactor (7) top material import, carry out continuous hydrolyzing reaction, tower reactor (7) bottom adopts recycle pump (8) that material is beaten to circulation, controlling the reaction time of reaction mass in tower reactor (7) by recycle pump (8) is 150～420 minutes, react complete, hydrolysis reaction liquid overflows from tower reactor (7) top, in tower reactor controlled hydrolysis reaction tower, temperature is at 220～240 DEG C,
3) the hydrolysis reaction liquid that tower reactor (7) discharge port overflows, by interchanger-2(5) shell side cooling after, enter in extraction tower (1), with extraction agent hybrid extraction, after phase-splitting, oil phase obtains Resorcinol crude product through precipitation, and water is transferred in material-compound tank (2), adds rodinal simultaneously and proceeds hydrolysis reaction.
The mol ratio of rodinal and hydrochloric acid in the present invention (concentration 30%) is 1:1-4, the mol ratio of rodinal and water is 1:50-180, hydrolysis temperature is controlled at 220～240 DEG C, and reaction solution is controlled at 150～420 minutes in tower reactor (7) residence time.
Above-mentioned steps 2 of the present invention) in, the hydrolysis material of rodinal is continuously by interchanger-2(5) when tube side with from the thermal hydrolysis reaction solution of tower reactor outflow at interchanger-2(5) shell side carry out thermal exchange, avoid heating up and cooling long problem non-cutting time, energy has obtained reasonable utilization simultaneously, has solved the large problem of energy consumption.
Line mixer of the present invention (4), tower reactor (7) and hydrolysis material contact surface adopt zirconium, tantalum with and alloy.
The present invention uses has extraction agent for butylacetate or propyl carbinol.
Aqueous phase extracted described in step 3) of the present invention enters after material-compound tank (2) out from extraction tower (1), adds into rodinal, and the amount adding is the inversion quantity of rodinal in hydrolytic process.Aqueous phase extracted described in step 3) contains ammonium chloride, and after repeatedly recycling, the ammonium chloride of water reaches capacity, and now hydrolysis material need to reconfigure.
The present invention is a kind of continuous, efficient, stable, clean Process of Hydroquinone Production technique, and its principal feature is:
Hydrolysis reaction carries out continuously in tower reactor, by the external heat coil pipe controlled hydrolysis temperature of reaction of tower reactor, the residence time by recycle pump control material in tower, control the transformation efficiency of rodinal by controlling temperature of reaction and reaction times, control transformation efficiency and be no more than 60%, thereby significantly reduce side reaction, reach highly selective and high yield.
Technique main advantage embodies in the following areas:
(1) hydrolysising mother liquid recycled, hydrolysising mother liquid has extracted after Resorcinol phase-splitting in extraction tower, gets back to material-compound tank, realizes sour recycled, only need to add rodinal.Wastewater flow rate is significantly reduced, reduce waste water more than 80%.
(2) continuous processing production technique has solved interrupter method and exists material mixed effect poor, and the excessively problem of hydrolysis reaction, reduces side reaction.Reduce input and output material simultaneously and heated up non-cutting time, effectively having improved the reaction efficiency of hydrolysis device, having reduced reaction time, having improved the production capacity of unit volume.By above-mentioned processing method, Resorcinol yield is more than 93%.
(3) adopt two groups of heat-exchanger rigs, realize the energy exchange of cold and hot material, both effectively utilized Heat of Hydrolysis material heat energy, can reduce again the investment of hydrolysis refrigerating device for materials.
Brief description of the drawings
Fig. 1 is the process flow sheet that p-aminophenol continuous hydrolysis is prepared Resorcinol.1. extraction tower; 2. material-compound tank; 3. volume pump; 4. line mixer; 5. interchanger-2; 6. interchanger-1; 7. tower reactor; 8. recycle pump.
Embodiment
Below by the drawings and specific embodiments, technical scheme of the present invention is described further, but protection scope of the present invention is not limited to this.Rodinal content 97%, derives from the thick product of p-aminophenol of Jiangsu manufacturing enterprise, and all the other reagent all have commercially available.
With air in nitrogen replacement feed proportioning system and hydrolysis reaction device.In material-compound tank (2), add water, 30% hydrochloric acid and rodinal, rodinal: hydrochloric acid: the mol ratio of water is 1:3:100.By volume pump (3), hydrolysis material is passed through to line mixer (4) according to the flow of 13Kg/min, through interchanger-2(5), again through interchanger-1(6) be warmed up to 230 DEG C, enter tower reactor (7) from tower reactor (7) top material opening for feed, tower reactor (7) volume is 1.5m3, blade diameter length ratio is 10, include four traverse baffles, keeping material reaction temperature in tower is 230 DEG C, at the bottom of tower, adopt recycle pump (8) extraction hydrolyzed solution continuously simultaneously, circulate, making reaction mass is 300 minutes at dwell time in the tower, hydrolysis reaction liquid is from tower reactor (7) top overflow, through interchanger-2(5) shell side, after cooling, enter extraction tower (1), with n-butyl acetate extraction, organic phase distillation, precipitation, then to obtain purity be 99.5% Resorcinol in rectification under vacuum, yield: 94%.In hydrolysis reaction, the transformation efficiency of rodinal is 60%, extraction tower (1) water is delivered to material-compound tank (2) from extraction tower bottom, add continuously into rodinal, additional amount is the inversion quantity of rodinal in reaction process.
According to method described in embodiment 1, different is is 200 minutes in the controlled hydrolysis reaction times.In hydrolysis reaction, the transformation efficiency of rodinal is 50%, extraction tower (1) water is delivered to material-compound tank (2) from extraction tower bottom, add continuously into rodinal, additional amount is the inversion quantity of rodinal in reaction process.It is 99.5% Resorcinol that extraction tower organic phase obtains purity after desolventizing distillation, yield: 95%.
According to method described in embodiment 1, different is is 150 minutes in the controlled hydrolysis reaction times.In hydrolysis reaction, the transformation efficiency of rodinal is 40%, extraction tower (1) water is delivered to material-compound tank (2) from extraction tower bottom, add continuously into rodinal, additional amount is the inversion quantity of rodinal in reaction process.It is 99.5% Resorcinol that extraction tower organic phase obtains purity after desolventizing distillation, yield: 98%.
According to method described in embodiment 1, different is that controlled hydrolysis temperature of reaction is 240 DEG C, and hydrolysis time is 200 minutes.In hydrolysis reaction, the transformation efficiency of rodinal is 55%, extraction tower (1) water is delivered to material-compound tank (2) from extraction tower bottom, add continuously into rodinal, additional amount is the inversion quantity of rodinal in reaction process.It is 99.5% Resorcinol that extraction tower organic phase obtains purity after desolventizing distillation, yield: 93%.
Claims (9)
1. the technique that Resorcinol is produced in the hydrolysis of p-aminophenol continuous processing, it is characterized in that: taking rodinal as raw material, after mixed in hydrochloric acid, be preheated to 220～240 DEG C, hydrolysis reaction 150-420 minute in tower reactor (7), react complete, hydrolysis reaction liquid overflows from tower reactor (7) discharge port, and hydrolysis reaction liquid obtains Resorcinol crude product after extraction, phase-splitting, precipitation.
2. technique as claimed in claim 1, is characterized in that: make the transformation efficiency of rodinal be no more than 60% by controlling temperature of reaction and reaction times.
3. technique as claimed in claim 1, it is characterized in that: this process using device comprises the material-compound tank (2) for preparing rodinal hydrolysis material, the line mixer (4) of mixed hydrolysis raw material, for interchanger-1(6 that mixing raw material is heated), interchanger-2(5), for the tower reactor (7) of the reaction that is hydrolyzed, for the extraction tower (1) of extracted products, the outlet and interchanger-2(5 of line mixer (4)) material inlet be communicated with, interchanger-2(5) with interchanger-1(6) connect, interchanger-1(6) material outlet be connected with tower reactor (7) top material import, tower reactor (7) discharge port and interchanger-2(5) shell side opening for feed be connected, interchanger-2(5) shell side outlet be connected with extraction tower (1) opening for feed, extraction tower (1) lower part outlet is connected with material-compound tank (2).
4. technique as claimed in claim 3, is characterized in that: tower reactor (7) outer wall is with heating coil, and blade diameter length ratio is 1:5-15, and tower includes 3-11 piece traverse baffle, and tower reactor (7) discharge port is provided with baffle plate.
5. technique as claimed in claim 1, is characterized in that, described technique comprises the steps:
1) by the hydrochloric hydrolysis material of material-compound tank (2) preparation rodinal, form the uniform rodinal aqueous solution through line mixer (4);
2) hydrolysis material of the rodinal preparing is first by interchanger-2(5) tube side enters interchanger-1(6) tube side, at interchanger-1(6) in by heating medium, material is preheating to after 220～240 DEG C, join continuously tower reactor (7) from tower reactor (7) top material import, carry out continuous hydrolyzing reaction, tower reactor (7) bottom adopts recycle pump (8) that material is beaten to circulation, controlling the reaction time of reaction mass in tower reactor (7) by recycle pump (8) is 150～420 minutes, react complete, hydrolysis reaction liquid overflows from tower reactor (7) top, in tower reactor controlled hydrolysis reaction tower, temperature is at 220～240 DEG C,
3) the hydrolysis reaction liquid that tower reactor (7) discharge port overflows, by interchanger-2(5) shell side cooling after, enter in extraction tower (1), with extraction agent hybrid extraction, after phase-splitting, oil phase obtains Resorcinol crude product through precipitation, and water is transferred in material-compound tank (2), adds rodinal simultaneously and proceeds hydrolysis reaction.
6. technique as claimed in claim 5, the mol ratio that it is characterized in that described rodinal and hydrochloric acid is 1:1-4, the mol ratio of rodinal and water is 1:50-180; Described concentration of hydrochloric acid is 30%.
7. technique as claimed in claim 5, it is characterized in that described line mixer (4), tower reactor (7) and hydrolysis material contact surface adopt zirconium, tantalum with and alloy.
8. technique as claimed in claim 5, is characterized in that described extraction agent is butylacetate or propyl carbinol.
9. technique as claimed in claim 5, is characterized in that aqueous phase extracted enters after material-compound tank (2) out from extraction tower, adds rodinal, and add-on is the inversion quantity of rodinal in hydrolytic process.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108863857A (en) * | 2018-06-29 | 2018-11-23 | 浙江龙盛化工研究有限公司 | The serial dilution device and method of N-acetylsulfanilyl chloride cooling crystallization |
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|---|---|---|---|---|
| JPS5257129A (en) * | 1975-10-07 | 1977-05-11 | Japan Synthetic Rubber Co Ltd | Process for hydroquinone |
| JPS5312824A (en) * | 1976-07-20 | 1978-02-04 | Mitsui Toatsu Chem Inc | Preparation of hydroquinone |
| CN1962593A (en) * | 2006-11-24 | 2007-05-16 | 王在军 | Pyrocatechin and hydroquinone production process |
| CN101735019A (en) * | 2009-12-31 | 2010-06-16 | 浙江龙盛化工研究有限公司 | Process for producing resorcinol by continuously hydrolyzing m-phenylenediamine |
| CN102276423A (en) * | 2011-06-28 | 2011-12-14 | 江苏科圣化工机械有限公司 | Method for producing hydroquinone by direct hydrolysis of p-phenylenediamine |
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- 2012-12-19 CN CN201210557199.9A patent/CN103880602A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5257129A (en) * | 1975-10-07 | 1977-05-11 | Japan Synthetic Rubber Co Ltd | Process for hydroquinone |
| JPS5312824A (en) * | 1976-07-20 | 1978-02-04 | Mitsui Toatsu Chem Inc | Preparation of hydroquinone |
| CN1962593A (en) * | 2006-11-24 | 2007-05-16 | 王在军 | Pyrocatechin and hydroquinone production process |
| CN101735019A (en) * | 2009-12-31 | 2010-06-16 | 浙江龙盛化工研究有限公司 | Process for producing resorcinol by continuously hydrolyzing m-phenylenediamine |
| CN102276423A (en) * | 2011-06-28 | 2011-12-14 | 江苏科圣化工机械有限公司 | Method for producing hydroquinone by direct hydrolysis of p-phenylenediamine |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108863857A (en) * | 2018-06-29 | 2018-11-23 | 浙江龙盛化工研究有限公司 | The serial dilution device and method of N-acetylsulfanilyl chloride cooling crystallization |
| CN108863857B (en) * | 2018-06-29 | 2024-04-30 | 浙江龙盛化工研究有限公司 | Continuous dilution device and method for cooling crystallization of acetamido benzenesulfonyl chloride |
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Application publication date: 20140625 |