CN1919822A - Novel method of synthesizing cinnamic acid by catalyzed oxidation cinnamic aldehyde - Google Patents
Novel method of synthesizing cinnamic acid by catalyzed oxidation cinnamic aldehyde Download PDFInfo
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- CN1919822A CN1919822A CN 200610019615 CN200610019615A CN1919822A CN 1919822 A CN1919822 A CN 1919822A CN 200610019615 CN200610019615 CN 200610019615 CN 200610019615 A CN200610019615 A CN 200610019615A CN 1919822 A CN1919822 A CN 1919822A
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Abstract
The invention discloses a cinnamic acid synthesizing method through cinnamaldehyde, which comprises the following steps: adopting silver/copper as catalyst and O2 as oxidant; dripping cinnamaldehyde to synthesize sodium cinnamate; acidifying sodium cinnamate to generate crystallized cinnamic acid; nitrating and reducing silver and copper to prepare silver/copper catalyst.
Description
Technical field
The novel method of a kind of synthesizing cinnamic acid by catalyzed oxidation cinnamic aldehyde of the present invention belongs to fine-chemical intermediate synthetic process field, is specifically related to catalysed oxidation processes.
Background technology
Styracin, chemical name 3-cinnamylic acid is a kind of important fine-chemical intermediate, is widely used in the production of products such as medicine, spices, plastics and sensitive materials, also be the intermediate of the prochirality compound of novel sweetener aspartame.
The manufacture method of styracin has many kinds, traditional styracin production method has Perkin method, benzylidene chloride---sodium acetate, anhydrous method and phenylformic acid---acetone condensation method, and the method for new development has the oxidation catalysis synthesis process.
1, Perkin method
The Perkin method is phenyl aldehyde and acetic anhydride preparation styracin under effect under the catalysis of sodium acetate, anhydrous (potassium).Since realizing industrialization the 1950's, its technology is gradually improved, and has become the main method of domestic and international production styracin
[1-8]Up to now, the method that generally adopts of preparation of industrialization styracin remains the Perkin reaction.But phenyl aldehyde and aceticanhydride price sharp rise in recent years, make the Perkin method produce the styracin cost and rise.Therefore, the Perkin method that is widely adopted faces the challenge.
2, benzylidene chloride---sodium acetate, anhydrous method
In the presence of inert diluent and catalyzer, make styracin by benzylidene halogenide and sodium-acetate reaction
[9]Benzylidene chloride---the side reaction of sodium acetate, anhydrous method is many, and productive rate is low, once adopted by the producer that with the benzylidene chloride is the production benzyl chloride of by product, but it is superseded now to have become.
3, phenyl aldehyde-ketone condensation method
This synthetic method once was used for producing, but because technical process is long, complicated operation, problem such as energy consumption is big, and transformation efficiency is low and being eliminated
[10,11]
4, catalytic oxidation
In recent years, catalytic oxidation prepares styracin and also is subjected to people day by day and payes attention to.As being catalyzer with the argent, 30% hydrogen peroxide is an oxygenant, 25-30 ℃ of logical nitrogen as the protection gas.Ice bath drips phenylacrolein and 33.3% sodium hydroxide simultaneously.After reaction finishes, filtering catalyst, acid out, styracin can obtain higher yield
[12]But this technology is comparatively loaded down with trivial details, and equipment requirements is higher, and exothermic heat of reaction is violent, is difficult to suitability for industrialized production.
Another kind is the molecular oxidation method, and wherein the liquid phase catalytic oxidation yield is lower, is about 70%, and also uses a large amount of organic solvents.For example: as catalyzer, with toluene, dimethylbenzene and water are solvent with Cobaltous diacetate, M-nitro benzoic acid cobalt, cobalt stearate, cobaltous bromide, and air is an oxygenant oxidation phenylacrolein synthesizing cinnamic acid.When the consumption of cobalt salt catalyst is the 0.1-20% of solvent quality, temperature of reaction is 30-80 ℃, and to be normal pressure all can react to 20Kg/cmG pressure.Yield when wherein being catalyzer with the Cobaltous diacetate is the highest, reaches 80.1%, content 99.8%
[13], but catalytic effect is still undesirable, and owing to use a large amount of organic solvents, serious environment pollution.
In addition, adopt silver to be adsorbed on the activated carbon in addition, prepared styracin with the method for atmospheric oxidation phenylacrolein as catalyst
[14-15], product purity can reach more than 99%, and yield is 95.8%.For example, people such as Luo Xiaoyan propose, and drip phenylacrolein in the aqueous solution of sodium hydroxide, are catalyzer with Ag/C, air is as oxygenant, in 40-45 ℃, synthesizing cinnamic acid obtains styracin through decolouring, acid out again, this method reaction conditions gentleness, time is short, the yield height, and catalyzer is reusable.But, Ag/C catalyzer cost height, the life-span is short, and consumption is big, and the styracin color that generates jaundice, needs decolouring, has limited industrialization development.
Other has bibliographical information, is 90%～100%H with concentration
2O
2, inorganic oxide such as NaClO is the catalysed oxidation processes of oxygenant
[16]The high density H that this method not only adopts
2O
2, and organic solvents such as a large amount of third cyanogen that adopts, benzene, these factors all are unfavorable for the industrializing implementation of this method.
Summary of the invention
The method that the purpose of this invention is to provide a kind of synthesizing cinnamic acid by catalyzed oxidation cinnamic aldehyde, be starting raw material promptly with phenylacrolein, make oxygenant with pure oxygen, to be adsorbed on the silver/copper catalyst on the carbon dust, replace the full silver catalyst on the carbon dust, the novel method of synthetic preparation styracin improves catalyzer work-ing life, simplify production technique, realize industrialized mass production with high yield.
Realize that technical scheme of the present invention comprises that with silver/copper be catalyzer, O
2Under the alkaline aqueous solution condition for oxygenant, suitable speed drips phenylacrolein synthesizing cinnamic acid sodium, Sodium.beta.-phenylacrylate is generated the method for styracin through acid out again; And the preparation of silver/copper catalyst, recovery and renovation process.
One, the method for this synthesizing cinnamic acid by catalyzed oxidation cinnamic aldehyde is to be catalyzer with silver/copper, O
2Under the alkaline aqueous solution condition for oxygenant, suitable speed drips phenylacrolein synthesizing cinnamic acid sodium, with Sodium.beta.-phenylacrylate process acid out, generates crystallization styracin product again.Particularly, present method comprises two-step reaction: the first step reaction is a catalyzer with silver/copper, with O
2Be oxygenant, alkaline condition drip down phenylacrolein, generate Sodium.beta.-phenylacrylate; The reaction of second step with the first step reaction product Sodium.beta.-phenylacrylate, generates styracin through acid out.
The two-step reaction that present method comprises is shown in following two reaction formula:
By present method, the mass ratio of water, alkali, phenylacrolein, four kinds of reaction partners of silver/copper catalyst is 10: 0.2: 1: 0.1 to 10: 1: 1: 0.1, and optimum proportion is 10: 0.3: 1: 0.1 to 10: 0.7: 1: 0.1;
Its processing condition are as follows:
Temperature of reaction is 20-80 ℃, and optimum temps is 40-60 ℃;
The rate of addition of phenylacrolein is about 0.1-0.3mL/min,
Oxygen gas flow rate is greater than 0.5L/min, and optimum flow rate is approximately 1L-8L/min.
Two, the preparation of silver/copper catalyst, recovery and renovation process.
1, about the preparation of silver/copper catalyst
Adopt argent, copper, prepare silver/copper catalyst through nitrated, reduction reaction:
Nitrated: as to press 3: 2 silver: the copper mol ratio, take by weighing silver, copper, in suitable quantity of water, slowly drip the nitric acid of 3.71-3.90 mole, the complete reaction after-filtration, the carbon dust that in filtrate, adds 0.5 mole, while Dropwise 5 0%NaOH solution, vigorous stirring, adjust basicity to pH=10-12, continue to stir one hour, filter, obtain nitration product: Silver Nitrate, cupric nitrate/carbon.；
Reduction: with above-mentioned nitration product Silver Nitrate, cupric nitrate/carbon, place water, drip the about 10mL of NaOH solution of 20-30%, controlled temperature is below 30 ℃, after dripping 0.07 moles of formaldehyde solution again, continue reaction 30-60 minute, obtain reduzate silver/copper catalyst.
2, silver/copper catalyst reclaims and regeneration
The deactivated catalyzer of filtered and recycled, with reference to above-mentioned silver/method for preparing copper catalyst, add excessive nitric acid dissolve, filter, take a sample, measure silver and copper content in the filtrate, the Silver Nitrate or the cupric nitrate that add requirement, the mol ratio of adjusting silver and copper is 3: 2, again by the described silver/copper catalyst that makes of above-mentioned preparation method.
3, silver/copper catalyst work-ing life
Ben Yin/copper catalyst long service life generally can reach 48-55 batch, when total silver measures 60% before content silver-colored in the catalyzer is less than use, as stated above silver/copper catalyst is carried out activating and regenerating.
Now present method is summarized as follows:
Under 20-80 ℃ of temperature condition, in the aqueous sodium hydroxide solution of what proportional concentration, behind the silver/copper catalyst of additional proportion amount, the beginning aerating oxygen, the control oxygen gas flow rate drips the phenylacrolein of proportional then within optimum flow rate 1L-8L/min, the rate of addition of phenylacrolein is approximately 0.1-0.3mL/min, dropwise the back and continued aerating oxygen about 15 minutes, the reaction that is generated Sodium.beta.-phenylacrylate by phenylacrolein stops.Sodium.beta.-phenylacrylate solution is filtered, elimination catalyzer slag, and washing filter residue, filter residue washing lotion and filtrate merge, and add dilute hydrochloric acid and regulate pH to 1 or 2, and the styracin white crystal is separated out, and filters, and the washing white crystal promptly obtains the styracin crystalline product to neutral.
By present method, four kinds of reaction partners, water: alkali: phenylacrolein: the ratio of the quality of silver/copper catalyst is 10: 0.2: 1: 0.1 to 10: 1: 1: 0.1, and optimum proportion is 10: 0.3: 1: 0.1 to 10: 0.7: 1: 0.1
When the ratio of above-mentioned each reaction partner, when exceeding above scale parameter scope, the reaction that phenylacrolein is oxidized to styracin can take place hardly, even taken place also to generate with a large amount of by products, productive rate is inevitable low.
Naoh concentration is bigger to the influence of reaction, if concentration is too high, then self polycondensation takes place phenylacrolein easily, generates a large amount of height product that boils productive rate is reduced greatly.If naoh concentration is too low, then cause catalyzed oxidation to be difficult to carry out.
Between 20 ℃ to 80 ℃, better temperature is approximately 30 ℃ to 70 ℃ to the temperature range of reaction greatly, and optimum temps is approximately 40 ℃ to 60 ℃.
Oxygen is the oxygenant in the entire reaction, and the pressure of reaction system and the flow velocity of oxygen have tremendous influence.If oxygen partial pressure and flow velocity cross low then oxidation is incomplete.Responseless phenylacrolein has stoped contacting of catalyzer and oxygen attached to catalyst surface, thereby makes poisoning of catalyst.Productive rate also begins rapid rising when oxygen partial pressure and oxygen gas flow rate increase gradually, reaches a stationary value thereupon.If continue to improve oxygen partial pressure and oxygen gas flow rate then yield can not improve basically again.Generally speaking, when oxygen gas flow rate just has oxidizing reaction to take place greater than 0.5L/min, the optimum oxygen flow velocity is approximately 1L/min to 8L/min.
The novel method of phenylacrolein catalyzed oxidation styracin of the present invention has significant technical progress, it makes the relevant intermediate product phenyl aldehyde-phenylacrolein-styracin of relevant chemical enterprise form an industrial chain, greatly reduce the raw materials for production cost of styracin, and can guarantee the supply in order as required of its raw material, replace silver or silver/C catalyzer with silver/copper catalyst, replace air with oxygen, its oxidation effectiveness and catalyzer obviously improve work-ing life, the recovery method of catalyzer silver/copper is simple, and rate of recovery height can reach more than 95%, and expense is low, reuse effectively, discharge of wastewater is few in addition, pollutes few.
Embodiment
How now further specify the present invention with experiment sample and scene example in batches respectively implements:
One, experiment sample
Example 1
In the 1000mL four-hole boiling flask, insert agitator, thermometer, a dropping funnel and a rubber hose that links to each other with oxygen cylinder.Add sheet alkali 20g, water 600mL, silver/copper catalyst 6g stirs and heats up aerating oxygen, flow velocity 4L/min, controlled temperature 45-50 ℃.Begin to drip cinnamic aldehyde 60g after 10 minutes, flow velocity 0.5g/min dropwises the back and continued logical oxygen 15 minutes.The elimination filter residue obtains yellow solution, the flushing of filter residue water.With the washing lotion merging filtrate, be warming up to 70-80 ℃, add hydrochloric acid, behind the adjusting pH to 2, cool to room temperature, suction filtration, drying had both obtained 64.5g styracin white crystal, and its fusing point is 132-133 ℃, and yield is 95.8%.
Example 2
Add sheet alkali 25g, silver/copper catalyst 9g, oxygen gas flow rate 3L/min, other conditions are identical with example 1, obtain 60.1g styracin white crystal, and its fusing point is 131-134 ℃, yield 89.3%.
Example 3
Add sheet alkali 17g, silver/copper catalyst 6g, temperature 65-70 ℃, other conditions are identical with example 1, obtain light yellow crystal.Product is added activated carbon decolorizing after with alkali dissolution, analyse and obtain 56.6g styracin white crystal adding sulfuric acid, its fusing point is 131-135 ℃, yield 84.1%.
Example 4
Add phenylacrolein 60g, flow velocity 1g/min, temperature 65-70 ℃, other condition examples 1 are identical with example 1, obtain light yellow crystal.Through obtaining white crystal 58.1g, yield 86.4% after the activated carbon decolorizing.
Two, on-the-spot in batches synthetic example
1, synthetic
With 14Kg silver/copper catalyst, 65Kg sheet alkali, 1.8T water stirs, and is warming up between 40-50 ℃, begins logical oxygen, when the still internal pressure is 0.08MPa, drips cinnamic aldehyde 200Kg flow velocity 120L/h, and oxygen gas flow rate is 9m
3/ h.Continue logical oxygen after dropwising and stirred 15 minutes, make it complete reaction.After oxygen stops, leaving standstill 15 minutes, filter, material is changed in the acid out still, 70-80 ℃ of acid out still intensification adds hydrochloric acid, behind adjustment and the stable pH=2, cools to 27 ℃.
2, get rid of material
Reducing to after 27 ℃ when the acid out temperature, begin to get rid of material, wash repeatedly with tap water when getting rid of material, is pH=5-6 until throwing away waste liquid, stops., material is waited to dry.
3, oven dry
To wait to dry by the fire material and drop into oven dry in the Vacuumdrier, temperature of charge is controlled at about 60-65 ℃, and the drying machine drying time is about 5-6 hour, behind the drying materials, obtains styracin finished product 231Kg.Sampling is analyzed, styracin content 99%, and yield reaches 95%.
About standard and quality
The novel method of phenylacrolein catalyzed oxidation styracin of the present invention is succeeded in developing, and takes the lead in guiding the company standard Q/WYC13-2004 that has formulated the styracin product, and its quality product meets U.S. food chemistry code FCC-IV standard (China does not have this same class standard).Its comparing result sees table.
Present method styracin product and FCC-IV standard comparison sheet
| Items of analysis (analysis project) | Specication (quality index) | The Results measured result |
| Appearance (outward appearance) | White to light yellow crystal powder (white is to pale yellow powder) | Complies (qualified) |
| Fragrance (odor type) | Balsam scent (balsamic tone) | Complies (qualified) |
| Assay (gas chromatography) content (meteorological look is known analysis well) | ≥99％min | 99％ |
| Melting point (centigrade): fusing point (℃) | ≥130℃ | 130-133℃ |
| Heavy meta; S (ppm) (heavy metal) | ≤10ppm | 8pm |
| Residue on ignition (residue on ignition) | ≤0.1％ | 0.09％ |
| Conc lusion (conclusion) | Conform to FCC IV (this product meets PCC IV standard) | |
Claims (4)
1, a kind of method of synthesizing cinnamic acid by catalyzed oxidation cinnamic aldehyde comprises two-step reaction: the first step reaction is a catalyzer with silver/copper, with O
2Be oxygenant, the alkaline aqueous solution condition under, suitable speed drips phenylacrolein, generates Sodium.beta.-phenylacrylate; The reaction of second step with the first step reaction product Sodium.beta.-phenylacrylate, generates styracin through acid out, and this two-step reaction is shown in following two reaction formula:
Four kinds of reaction partner water: alkali: phenylacrolein: the mass ratio of silver/copper catalyst is 10: 0.2: 1: 0.1 to 10: 1: 1: 0.1; Temperature of reaction is 20-80 ℃; The rate of addition of phenylacrolein is 0.1-0.3mL/min; Oxygen gas flow rate is greater than 0.5L/min.
2, according to the method for a kind of synthesizing cinnamic acid by catalyzed oxidation cinnamic aldehyde of claim 1, described four kinds of reaction partners, water: alkali: phenylacrolein: the optimum proportion of the quality of silver/copper catalyst is 10: 0.3: 1: 0.1 to 10: 0.7: 1: 0.1; Optimal reaction temperature 40-60 ℃; The best rate of addition of phenylacrolein is 0.1-0.3mL/min; The optimum oxygen flow velocity is 1L-8L/min (lab scale).
3, according to the novel method of a kind of synthesizing cinnamic acid by catalyzed oxidation cinnamic aldehyde of claim 1, the preparation method of described silver/copper catalyst is with argent, copper, prepares silver/copper catalyst through nitrated, reduction reaction:
Nitrated: as to press 3: 2 silver: the copper mol ratio, take by weighing silver, copper, in suitable quantity of water, slowly drip the nitric acid of 3.71-3.90 mole, the complete reaction after-filtration, the carbon dust that in filtrate, adds 0.5 mole, while Dropwise 5 0%NaOH solution, strong mixing is adjusted basicity to pH=10-12, filter, obtain nitration product: Silver Nitrate, cupric nitrate/carbon;
Reduction: with above-mentioned nitration product Silver Nitrate, cupric nitrate/carbon, place water, drip the about 10mL of NaOH solution of 20-30%, controlled temperature drips 0.07 moles of formaldehyde solution again below 30 ℃, continues reaction, obtains reduzate silver/copper catalyst.
4, the renovation process according to the silver/copper catalyst of the silver/method for preparing copper catalyst of claim 3 is: reclaim deactivated catalyzer, add excessive nitric acid and make it dissolving, the complete reaction after-filtration, measure silver and copper content in the filtrate, the Silver Nitrate or the cupric nitrate that add requirement, the mol ratio of adjusting silver and copper is after 3: 2, presses the silver/method for preparing copper catalyst of claim 3 again, this silver/copper catalyst of regenerating.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101857541A (en) * | 2010-05-28 | 2010-10-13 | 湖北远成药业有限公司 | Method for preparing potassium cinnamate |
| CN102826992A (en) * | 2012-09-28 | 2012-12-19 | 湖北远成药业有限公司 | Novel industrialized synthesis technique for preparing cinnamic acid from cinnamic aldehyde by catalytic oxidation |
| CN108250069A (en) * | 2018-01-22 | 2018-07-06 | 万华化学集团股份有限公司 | A kind of preparation method of isooctyl acid |
| CN111733192A (en) * | 2020-07-03 | 2020-10-02 | 湖北大学 | Novel enzyme catalysis method for preparing cinnamic acid from cinnamaldehyde and application |
-
2006
- 2006-07-13 CN CN 200610019615 patent/CN1919822A/en active Pending
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101857541A (en) * | 2010-05-28 | 2010-10-13 | 湖北远成药业有限公司 | Method for preparing potassium cinnamate |
| CN102826992A (en) * | 2012-09-28 | 2012-12-19 | 湖北远成药业有限公司 | Novel industrialized synthesis technique for preparing cinnamic acid from cinnamic aldehyde by catalytic oxidation |
| CN102826992B (en) * | 2012-09-28 | 2015-09-02 | 湖北远成赛创科技有限公司 | Phenylacrolein catalyzed oxidation prepares the industrialization new synthetic process of styracin |
| CN108250069A (en) * | 2018-01-22 | 2018-07-06 | 万华化学集团股份有限公司 | A kind of preparation method of isooctyl acid |
| CN108250069B (en) * | 2018-01-22 | 2021-01-15 | 万华化学集团股份有限公司 | Preparation method of isooctanoic acid |
| CN111733192A (en) * | 2020-07-03 | 2020-10-02 | 湖北大学 | Novel enzyme catalysis method for preparing cinnamic acid from cinnamaldehyde and application |
| CN111733192B (en) * | 2020-07-03 | 2021-12-03 | 湖北大学 | Novel enzyme catalysis method for preparing cinnamic acid from cinnamaldehyde and application |
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