CN1325159C - Catalyzer for preparing p-aminophenol by using hydrogenation rearrangement through selection of nitrobenzene - Google Patents
Catalyzer for preparing p-aminophenol by using hydrogenation rearrangement through selection of nitrobenzene Download PDFInfo
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- CN1325159C CN1325159C CNB2004100220864A CN200410022086A CN1325159C CN 1325159 C CN1325159 C CN 1325159C CN B2004100220864 A CNB2004100220864 A CN B2004100220864A CN 200410022086 A CN200410022086 A CN 200410022086A CN 1325159 C CN1325159 C CN 1325159C
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- aminophenol
- nitrobenzene
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Abstract
The present invention provides a catalyst for the preparation of para-aminophenol from nitrobenzene by hydrogenation and rearrangement. In the method, under the existence of the bifunctional catalyst, the nitrobenzene in an acidic solution or a non-acidic solution reacts with H2 for preparing the para-aminophenol (PAP) with high yield at the temperature of 60 to 120 DEG C, solid acids are adopted as the carrier of the bifunctional catalyst as well as the acidic active centre of the catalyst, and precious metal platinum is adopted as a main active ingredient for hydrogenation. Methods for synthesizing the PAP by adopting the catalyst have the characteristics of high yield, high selectivity, simple operation, easy industrialization, etc.
Description
The present invention relates to a kind of catalyst of making para-aminophenol, its characteristics are that New-type bifunctional acidity of catalyst surface can promote the rearrangement of hydrogenation of chloronitrobenzene intermediate.
Para-aminophenol is a kind of important organic intermediate, is mainly used in pharmaceutical production such as paracetamol, clofibrate, Cobastab, compound niacinamide, 6-oxyquinoline at pharmaceutical industry; Be used for the preparation of disperse dyes and sulfur dye at dye industry; Also be used for rubber antioxidant and photographic developer etc. in addition.Purposes is wide, the demand steady growth, and consumption figure reached 120,000 tons whole world para-aminophenol year in recent years; Estimate 2005, world's para-aminophenol aggregate consumption will reach 140,000 tons.Expectation China in this year will reach about 4.0 ten thousand tons to the aggregate demand of para-aminophenol, and 2005 annual requirements will reach about 4.8 ten thousand tons/year.And the total output of China has only about 3.5 ten thousand tons at present, and breach is bigger, and exploitation prospect is very wide.
The production method of para-aminophenol mainly contains: 1 p-nitrophenol metallic reducing method, 2 nitrophenol catalytic hydrogenating reduction methods, 3 p-nitrophenol electrolytic reductions, 4 nitrobenzene metallic reducing methods, 5 nitrobenzene electrolytic reductions, 6 nitrobenzene catalytic hydrogenating reduction methods.P-nitrophenol iron powder reducing method technology is simple, side reaction is few, equipment investment is few, but complex operation, cost height, unstable product quality, " three wastes " are more, and environmental pollution is more serious, and the high unsuitable pharmacy of iron content in the product; It is little that p-nitrophenol catalytic hydrogenating reduction method is polluted, but catalyst and solvent cost an arm and a leg, and material purity is required high, is difficult to and traditional iron powder reducing method competition; The nitrobenzene electrolytic reduction is simple to operate, flow process is short, product purity is high, pollution is little, is the external method that generally adopts, but this method has higher specification requirement to DESIGN OF REACTOR and process conditions control, and energy consumption is higher.Catalytic hydrogenation of nitrobenzene method raw material is cheap and easy to get, and production cost is low, operation is few, product yield and quality are good, but because the diluted acid corrosivity in the reaction is stronger, thereby equipment material is had relatively high expectations.
So a large amount of research work of people in recent years concentrate on the synthetic para-aminophenol of nitrobenzene hydrogenization method, this method is owing to use hydrogen and the catalyst p-nitrophenyl that can recycle to carry out hydrogenation reaction, reduced pollution to environment, the nitrobenzene raw material is cheap and easy to get, reduced cost, energy consumption of reaction is not high simultaneously.Wherein most of patents all adopt Pt/C, and Pt/ aluminium oxide, Pt/ nylon are catalyst, hydrogenation of chloronitrobenzene reduction preparation para-aminophenol in the presence of surfactant, acid medium.Chinese patent CN85103667A for example, the employed catalyst of the synthetic method of the disclosed para-aminophenol of CN1087263A is the Pt/ C catalyst, DTAC is a surfactant, selectivity is good, it is dark but the hole of this kind catalyst activity carbon is thin, product easily stops up endoporus and catalysqt deactivation, metal are also run off easily, and is bigger to the life of catalyst influence.U.S. Pat 4,885,389 and US4,264,529 disclosed para-aminophenol synthetic methods have been used Pt/C or Pt/ aluminium oxide, and wherein Pt/ aluminium oxide catalyst carrier in the presence of acid medium dissolves easily, and catalyst loss is serious.The disclosed para-aminophenol synthetic method of Chinese patent CN1075489C has been used the Pt/ nylon catalyst, and catalyst stability is better, but has the defective of PAP poor selectivity.U.S. Pat 4,307,249 and US4,176, the synthetic method of 138 disclosed preparation para-aminophenol has been used different surfactants, and the existence of surfactant can promote the dissolving of nitrobenzene, improve catalytic reaction activity, but can increase the difficulty of product post processing, influence product purity.US3,953,509 disclosed para-aminophenol synthetic methods have been used platinum sulfide or molybdenum sulfide/C catalyst, and used sulfuric acid concentration reaches 50%.US6,403,833 disclosed para-aminophenol synthetic methods have been used nickel/ZSM-5 catalyst, and the PAP selectivity is very low.US6,028,227 disclosed para-aminophenol synthetic method has been used the Pt-S/C catalyst, adds solid acid (ion exchange resin) simultaneously, carries out nitrobenzene hydrogenation in aqueous medium.But selectivity is very low, less than 10%.
The objective of the invention is to develop the method for a kind of bifunctional catalyst and a kind of practicable system para-aminophenol, solve PAP selectivity of the prior art and the not high problem of yield, and significantly reduce the acid concentration of reaction medium.
Bifunctional catalyst provided by the invention is the difunctional platinum based catalyst that a kind of hydrogenation of chloronitrobenzene is reset the system para-aminophenol, described bifunctional catalyst is to be carrier with the solid acid, and the Pt that with the percentage by weight is 0.5-3% is the bifunctional catalyst of active component; Wherein said carrier is strong-acid ion exchange resin, support heteropoly acid, HF-ZSM-5, HF-SiO
2, KF-SiO
2In one or more.
Wherein, the described heteropoly acid that supports is to adopt active carbon, molecular sieve, silica or alundum (Al as carrier.
The concise and to the point process of bifunctional catalyst preparation can for:
The solid acid that takes by weighing a certain amount of prescribed particle size is put into beaker; Platinum acid chloride solution according to the platinum containing amount preparation certain volume for preparing catalyst adds in solid acid this solution and stirring; In water-bath Back stroke method solvent, dry back is in the uniform temperature roasting in the baking oven behind the dipping certain hour, and reduction makes bifunctional catalyst in the hydrogen atmosphere; Or after drying, use formic acid, sodium formate, formaldehyde, potassium borohydride reduction.
Above-mentioned dilute acid soln is example 0-20% with the sulfuric acid concentration, is preferably 3-10%.Nonacid solution can be water, ethanol, cyclohexane.The process conditions of hydrogenation reaction are: reaction temperature 60-100 ℃, be preferably 70-90 ℃; Reacting system pressure 0.01～2.0MPa is preferably 0.1～0.5MPa; Catalyst amount is 4.12 * 10 with the molar ratio computing of Pt and nitrobenzene
-3～2.52 * 10
-6: 1, be preferably 2.52 * 10
-4～2.52 * 10
-5
Compared with prior art, the present invention has following advantage and effect:
The present invention succeeds in developing bifunctional catalyst and can be used for synthetic para-aminophenol of one step of hydrogenation of chloronitrobenzene rearrangement, has significantly improved the selectivity of target product PAP; And removed surfactant, hydroconversion condition relaxes, and is easy and simple to handle, reduced sour consumption, and cost of material is low, for the industrial production para-aminophenol provides a kind of reality feasible method.
Details is seen the following examples:
Embodiment 1
Respectively with HF-SiO
2, KF-SiO
2, ZSM-5, SiO
2Aerosol, γ-Al
2O
3Be carrier, it is 15% phosphorus heteropoly tungstic acid that dipping supports metering, and vacuum drying makes and supports heteropoly acid.With metering Pt is that 1% platinum acid chloride solution is a catalyst precursor, HF-SiO2, KF-SiO2, the heteropoly acid that supports of ZSM-5 and above-mentioned preparation is a carrier, dipping 3-120min, 60 ℃ of-100 ℃ of water-bath solvent flashings, 80 ℃ of-200 ℃ of dryings, 20 ℃-500 ℃ reduction preparation bifunctional catalysts are used for the reaction that hydrogenation of chloronitrobenzene is reset the system para-aminophenol.The nitrobenzene hydrogenation process is: bifunctional catalyst and reaction medium are dropped in the there-necked flask, nitrobenzene is put into constant pressure funnel, sealing system with hydrogen exchange five times, and links to each other air in the system with the hydrogen metering bottle.Drip and to put nitrobenzene and begin reaction, the consumption of hydrogen in the record course of reaction, thus measure activity of such catalysts, product obtains the selectivity and the space-time yield of nitrobenzene turn over number, para-aminophenol, result such as table 1 through liquid-phase chromatographic analysis.
Table 1 supports heteropoly acid and is used for the PAP preparation as the catalyst of the preparing carriers of bifunctional catalyst
| The reaction lot number | Catalyst | The average hydrogen degree ml/min that inhales | Selectivity % | Nitrobenzene turn over number mmol/min.gPt | PAP space-time yield mmol PAP/min.gPt |
| 1 2 3 4 5 6 7 8 | Pt/HF-SiO 2 Pt/PW-HF-SiO 2 Pt/KF-SiO 2 Pt/PW-KF-SiO 2 Pt/ZSM-5 Pt/PW-ZSM-5 Pt/PW-SiO 2 Pt/PW-Al 2O 3 | 6.28 9.81 2.93 8.44 2.35 4.7 9.48 11.35 | 40.87 48.43 77.51 53.58 80.5 44.59 51.03 79.57 | 51.77 71.84 27.38 64.65 20.80 41.30 71.10 68.58 | 21.16 34.79 21.22 34.64 16.77 18.42 36.28 54.57 |
(annotate: reaction condition is in the table: 85 ℃ of temperature, and the pressure normal pressure, nitrobenzene throwing amount 24mmol, catalyst amount is (in Pt) 0.2-2.6 * 10
-5Mol, reaction medium 30ml; Selectivity is meant the ratio of para-aminophenol mole and para-aminophenol and aniline integral molar quantity.The nitrobenzene turn over number is meant that the every gram of per minute Pt goes up the nitrobenzene mole that transforms, and the PAP space-time yield is meant the PAP mole that obtains on the every gram of the per minute Pt.)
The result shows that supporting the catalyst activity that heteropoly acid do not support the preparing carriers of heteropoly acid significantly increases, and the PAP space-time yield also increases to some extent.Al
2O
3Support the catalyst that catalyst activity, selectivity, PAP yield that heteropoly acid is a preparing carriers all are better than supporting with other preparing carriers of heteropoly acid.
Embodiment 2
With molecular sieve ZSM-5, HY uses HF solution-treated 4h respectively, and suction filtration is washed to neutrality, and 110 ℃ of dryings get catalyst carrier HF-ZSM-5, HF-HY.Respectively with ZSM-5, HY, HF-ZSM-5, HF-HY are the preparing carriers bifunctional catalyst, catalyst preparation process and nitrobenzene hydrogenation process are with reference to embodiment 1.Reaction result sees Table 2.
The various molecular sieves of table 2 are used for the PAP preparation as the catalyst of the preparing carriers of bifunctional catalyst
| The reaction lot number | Catalyst | The average hydrogen degree ml/min that inhales | Selectivity % | Nitrobenzene turn over number mmol/min.gPt | PAP space-time yield mmol PAP/min.gPt |
| 5 9 10 11 | Pt/ZSM-5 Pt/HF-ZSM-5 Pt/HY Pt/HF-HY | 2.35 4.3 6.09 5.68 | 80.5 79.03 53.97 75.26 | 20.80 42.37 35.82 56.46 | 16.77 33.48 19.33 42.49 |
(annotate: reaction condition is with table 1 in the table)
The result shows the molecular sieve ZSM-5 that handles through HF, and HY is used for hydrogenation of chloronitrobenzene as the bifunctional catalyst of preparing carriers, and no matter reset the system para-aminophenol be the nitrobenzene turn over number, or the PAP space-time yield is all than the fashion that is untreated; Concerning the HY system, the selectivity of product P AP brings up to 75.3% from 61.8%.
Embodiment 3
With Pt/HY is catalyst, respectively with water, and 5% sulfuric acid, 7.5% sulfuric acid, 15% sulfuric acid are reaction medium, carry out hydrogenation of chloronitrobenzene with reference to embodiment 1 and reset the system para-aminophenol.Reaction result sees Table 3.
Pt/HY is used for the PAP preparation as bifunctional catalyst under the different sulfuric acid concentrations of table 3
| The reaction lot number | Reaction medium | The average hydrogen degree ml/min that inhales | Selectivity % | Nitrobenzene turn over number mmol/min.gPt | PAP space-time yield mmol PAP/min.gPt |
| 12 13 14 15 | Water 5% sulfuric acid 7.5% sulfuric acid 15% sulfuric acid | 1.57 6.04 6.07 6.09 | 28.54 43.43 60.61 60.79 | 1.72 44.29 36.82 35.82 | 0.46 19.24 22.36 21.33 |
(annotate: reaction condition is with table 1 in the table)
The result shows that sulfuric acid concentration is not high more good more in the bibliographical information, as long as the amino salify dissolving desorption of product.This shows that reaction with bifunctional catalyst catalysis has significantly reduced the demand to sulfuric acid concentration.
Embodiment 4
With the strongly acidic cation-exchange is carrier, prepares catalyst with reference to the method for embodiment 1, wherein floods behind the 45min 80 ℃ of water-baths and steams near and do, and logical hydrogen reducing gets the Pt/ resin catalyst.Carry out hydrogenation of chloronitrobenzene with reference to embodiment 1 and reset the system para-aminophenol.
Table 4.Pt/ resin is used for the PAP preparation as bifunctional catalyst
| The reaction lot number | Reaction medium | The average hydrogen degree ml/min that inhales | Selectivity % | Nitrobenzene turn over number mmol/min.gPt | PAP space-time yield mmol PAP/min.gPt |
| 16 17 | Water 15% sulfuric acid | 1.44 1.358 | 63.88 99.52 | 4.58 14.83 | 2.93 14.75 |
(annotate: reaction condition is with table 1 in the table)
The result shows that the Pt/ resin is used for the PAP preparation as bifunctional catalyst very high selectivity is arranged, and is 99.52%.Even with water is that reaction medium also has 63.88% selectivity; But catalyst activity is not high.
Claims (2)
1. a hydrogenation of chloronitrobenzene is reset the difunctional platinum based catalyst of system para-aminophenol, it is characterized in that: described bifunctional catalyst is to be carrier with the solid acid, and the Pt that with the percentage by weight is 0.5-3% is the bifunctional catalyst of active component; Wherein said carrier is strong-acid ion exchange resin, support in the heteropoly acid one or more; Wherein, the described heteropoly acid that supports is to adopt active carbon, molecular sieve, silica or alundum (Al as carrier.
2. reset the difunctional platinum based catalyst of system para-aminophenol according to the described hydrogenation of chloronitrobenzene of claim 1, it is characterized in that: described bifunctional catalyst is to use hydrogen reducing again after dry under the 60-500 ℃ of temperature and roasting, or obtains with a kind of reduction in formic acid, sodium formate, formaldehyde, the potassium borohydride.
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|---|---|---|---|
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|---|---|---|---|
| CNB2004100220864A CN1325159C (en) | 2004-03-22 | 2004-03-22 | Catalyzer for preparing p-aminophenol by using hydrogenation rearrangement through selection of nitrobenzene |
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| CN1325159C true CN1325159C (en) | 2007-07-11 |
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Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101182300B (en) * | 2007-12-12 | 2010-04-14 | 河北工业大学 | Quaternary ammonium ionic liquid as well as preparation and application method thereof |
| CN101722032B (en) * | 2009-12-10 | 2013-11-27 | 复旦大学 | Catalyst for synthesizing p-aminophenol by hydrogenation reduction of nitrobenzene and preparation method thereof |
| CN102600891A (en) * | 2012-02-15 | 2012-07-25 | 辽宁石油化工大学 | Catalyst for preparing para-aminophenol by performing nitrobenzene selective hydrogenation in non-acid medium |
| CN112138650A (en) * | 2020-09-17 | 2020-12-29 | 张国良 | Method for preparing special catalyst for producing p-aminophenol by nitrobenzene hydrogenation |
| CN112010765B (en) * | 2020-09-24 | 2022-11-15 | 河北工业大学 | Method for preparing p-aminophenol by transfer hydrogenation of nitrobenzene |
| CN112657542B (en) * | 2020-12-28 | 2023-09-22 | 常州大学 | Method for preparing p-aminophenol from nitrobenzene |
| CN115722254A (en) * | 2021-08-31 | 2023-03-03 | 浙江工业大学 | Preparation method and application of in-situ packaged Pt @ H-ZSM-5 catalyst |
| CN113731453B (en) * | 2021-09-17 | 2022-05-10 | 吉林化工学院 | Preparation method and application of nitrogen-doped carbon-loaded heteropoly acid nano composite material |
| CN113731454B (en) * | 2021-09-22 | 2023-05-05 | 吉林化工学院 | Preparation and catalytic application of heteropolyacid-loaded nitrogen-doped carbon composite material |
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| CN1054596C (en) * | 1995-04-24 | 2000-07-19 | 环球油品公司 | C8 uromatic compound isomerizate of catalyst using molecular sieve containing modified silico-aluminium phosphate |
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