CN1709850A - DL-amygdalic acid preparing method - Google Patents
DL-amygdalic acid preparing method Download PDFInfo
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- CN1709850A CN1709850A CN 200510021135 CN200510021135A CN1709850A CN 1709850 A CN1709850 A CN 1709850A CN 200510021135 CN200510021135 CN 200510021135 CN 200510021135 A CN200510021135 A CN 200510021135A CN 1709850 A CN1709850 A CN 1709850A
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Abstract
This invention has disclosed a kind of producing method for DL-mandelic acid; comprising the steps of: cyanidation, mix benzaldehyde with acidity or alkaline catalyst, supplement water, add cyaniding hydrogen air or hydrocyanic acid solution, react to mandelonitrile; -hydrolysis, put mineral acid into the solution and hydrolyze, form hydrolysis solution contained DL-mandelic acid and mineral acid ammonium salts after hydrolysis entirety; -crystal, supplement water and cycle mother liquor into hydrolysis solution, crystallisate by cooling, centrifugal separate to find DL-mandelic acid coarse product and mother liquor contains DL-mandelic acid and mineral acid ammonium salts; mother liquor handling, adding inorganic basic substance, crystallisate by cooling after ordinary pressure or reduction concentrating, centrifugally get rid of mineral acid ammonium salts, the rest mother liquor recycle to hydrolysis procedure; DL-mandelic acid refining, dissolve DL-mandelic acid coarse product into water, add active carbon to decolor, filtrate, crystal, centrifugation and drying to gain DL-mandelic acid finished product whose yield is high and cost is low.
Description
Technical field:
The present invention is relevant with the preparation method of amygdalic acid, and is special relevant with the preparation method of DL-amygdalic acid.
Background technology
The existing method for preparing amygdalic acid has following several, and all there is weak point in these methods:
1, the phenyl aldehyde phase transfer catalysis process: this method is a starting raw material with the phenyl aldehyde, mixes with chloroform in alkaline environment, obtains amygdalic acid in next step reaction of phase-transfer catalyst effect, and reaction solution gets product through last handling processes such as extraction, drying, evaporation, recrystallizations.PTC reagent preparation difficulty, the more high factor of expense and also not industrialization.
2, benzene-acetaldehyde acid system: this method is a starting raw material with the oxoethanoic acid, obtains amygdalic acid with the benzene single step reaction in acetic aid medium, reaction solution through phase-splitting, transfer PH, concentrate, last handling processes such as filtration, drying get product, the not high and oxoethanoic acid of yield costs an arm and a leg, and cost is higher.
3, the methyl phenyl ketone chlorination process: this method is a starting raw material with the methyl phenyl ketone, gets dichloroacetophenone through chlorination, gets crude product through basic hydrolysis, acidifying, extraction, process such as concentrate again, and the crude product recrystallization gets product.Yield is in methyl phenyl ketone 80%.Be present main industrialized preparing process, but present method step being more, and with an organic solvent not only being difficult to avoid environmental pollution in the process, also is disadvantageous to industrial production.
4, traditional phenyl aldehyde cyanide process: this method is reacted with phenyl aldehyde, S-WAT, sodium cyanide or is got mandelonitrile with anhydrous prussic acid reaction addition with phenyl aldehyde in organic solvent, mandelonitrile gets the amygdalic acid reaction solution through separating posthydrolysis, the reaction solution last handling processes such as desalination, crystallization that dewater through toluene get crude product, crude product is getting product through the organic solvent recrystallization, and yield counts 55% with phenyl aldehyde.Present method productive rate is low, and quantity of three wastes is big, and the pollution that organic solvent causes is difficult to solve.Byproduct ammonium chloride is of poor quality, further difficult treatment.
Summary of the invention:
The objective of the invention is in order to overcome above deficiency, the preparation method of a kind of high yield, low cost, DL-amygdalic acid that quantity of three wastes is few is provided.
The object of the present invention is achieved like this:
The preparation method of amygdalic acid of the present invention comprises the steps;
The preparation method of DL-amygdalic acid of the present invention comprises the steps:
1), cyaniding: with phenyl aldehyde and acidity or basic catalyst mixing, add water by 0.1～5 times of phenyl aldehyde weight, phenyl aldehyde in molar ratio: prussic acid=1: 0.8～1.5, add weight percent content and be 3～20% prussic acid gas or weight percent content and be 30%～100% hydrocyanic acid aqueous solution, the synthetic mandelonitrile of reaction;
2), hydrolysis: above-mentioned mandelonitrile and reaction solution directly add mineral acid without separating, and 30～100 ℃ of following hydrolysis, the consumption of mineral acid is 0.5～3 times of mandelonitrile mole number, is formed with the hydrolyzed solution of DL-amygdalic acid and inorganic acid ammonium salt after hydrolysis is finished;
3), crystallization: replenishment cycles mother liquor and/or water in said hydrolyzed liquid, the mother liquor that replenishes and/jellyfish liquid measure summation is 0.1～3 times of hydrolyzed solution weight, then 0～30 ℃ of crystallization, the DL-amygdalic acid crude product that centrifugation obtains and contain the mother liquor of DL-amygdalic acid crude product and inorganic acid ammonium salt;
4), mother liquor is handled: in the above-mentioned mother liquor that contains DL-amygdalic acid crude product and inorganic acid ammonium salt, add inorganic base substance, add-on be in the mother liquor total acid mole number 50～150%, normal pressure or be decompressed to absolute pressure 0～0.09MPa and concentrate the back at 0～30 ℃ of scope intercrystalline, the centrifugal inorganic acid ammonium salt of removing, residue Recycling Mother Solution to hydrolyzing process uses;
5), the DL-amygdalic acid is refining: DL-amygdalic acid crude product is dissolved in water, and amount of water is 1～10 times of DL-amygdalic acid crude product weight, add activated carbon decolorizing by 0.5～8% of crude product weight, filtrate is at 0～30 ℃ of scope intercrystalline, and centrifugal drying gets finished product, and recrystallization mother liquor recycles.
When using basic catalyst in the above-mentioned method, temperature of reaction is-20～30 ℃.
Above-mentioned basic catalyst is at least a kind of in sodium hydroxide, potassium hydroxide, ammonia, the organic amine, and consumption is 0.01～10% of a phenyl aldehyde mole number, and organic amine is Trimethylamine 99 or triethylamine or Diisopropylamine.
When using an acidic catalyst in the above-mentioned method, the cyanogenation temperature is 50～100 ℃.
Above-mentioned an acidic catalyst is a kind of in sulfuric acid, hydrochloric acid, phosphoric acid, the oxalic acid, and its consumption is 0.01～10% of a phenyl aldehyde mole number.
Above-mentioned inorganic base substance is sodium hydroxide or potassium hydroxide or ammonia.
Above-mentioned mineral acid is at least a kind of in sulfuric acid, hydrochloric acid, the phosphoric acid.
Chemical equation involved in the present invention is as follows:
In the above-mentioned reaction formula, X=SO
4 2-, Cl
-, PO
4 3-M=Na
+, K
+, NH
4 +N=1-3.
In the present invention, cyanogenation can adopt hydrocyanic acid aqueous solution or prussic acid gas, does not especially need strict dehydration.On the contrary, be favourable having in the presence of the water to reaction control.Be reflected under acidity or the basic catalyst effect and carry out.
In the manufacture method provided by the invention, because that catalyzer is selected is proper, reaction conversion ratio height, selectivity are good; Reaction process need not carried out in organic solvent, has reduced pollutent; By product separates thoroughly with the purpose product, and purpose product treating process suppresses easily, and is simple to operate.Produce DL-amygdalic acid yield height with present method, cost is low, and the three wastes are few, the production efficiency height.
Embodiment:
Embodiment 1:
In the 1000L reactor, add phenyl aldehyde (weight percent content is 99%) 450kg, water 450kg, concentrated sulfuric acid catalyst 7.5kg, feeding weight percent contents at 70～80 ℃ is 8% prussic acid gas, dominant discharge is also calculated the prussic acid weight that feeds.When feeding prussic acid weight reaches 120kg, stop to feed.Insulation reaction finished in 0.5 hour.Cyanogenation liquid is gone to the 2000L hydrolysis reactor, slowly add vitriol oil 255kg down, finish insulation reaction and finished in 2 hours at 80～90 ℃.DL-amygdalic acid content in the analytical reaction liquid is 47.2% (HPLC), adds water 600L, is cooled to 10 ℃ of crystallizations, centrifugal, get DL-amygdalic acid crude product 630kg, water content 7%, in butt DL-amygdalic acid content is 96.2% (acid base titration), and reacting a yield is 88.2%.Mother liquor 1150L contains DL-amygdalic acid 53g/L (HPLC) after measured in the mother liquor.
Above-mentioned DL-amygdalic acid crude product adds entry 1200kg, gac 12kg, and the heated and stirred decolouring was filtered in 1 hour, filtrate is 8 ℃ of crystallizations, through centrifugal, and dry white DL-amygdalic acid crystalline product 528kg, content 99.3%, fusing point: 118.6～119.3 ℃, yield 82.1% of product.
Embodiment 2:
In the 1000L reactor, add phenyl aldehyde (weight percent content is 99%) 450kg, water 450kg, concentrated sulfuric acid catalyst 7.5kg, feeding weight percent contents at 70～80 ℃ is 8% prussic acid gas, dominant discharge is also calculated the prussic acid amount that feeds.When feeding prussic acid weight reaches 120kg, stop to feed.Insulation reaction finished in 0.5 hour.Cyanogenation liquid is gone to the 2000L hydrolysis reactor, slowly add vitriol oil 255kg down, finish insulation reaction and finished in 2 hours at 80～90 ℃.DL-amygdalic acid content in the analytical reaction liquid is 47.2% (HPLC).
Add liquid ammonia 27.0kg in the hydrolysising mother liquid of embodiment 1,10 ℃ of following crystallizations, centrifugation goes out producing ammonium sulfate byproduct to mother liquor behind concentrating under reduced pressure, the heavy 320kg of dry back by product, content 96.5%.Residual filtrate adds in the said hydrolyzed liquid, is cooled to 10 ℃ of crystallizations, and is centrifugal, gets DL-amygdalic acid 674kg, and water content 7.2% is in butt DL-amygdalic acid content 95.5%.DL-amygdalic acid reaction yield is 93.5%.Mother liquor recycles by above-mentioned steps.
Above-mentioned DL-amygdalic acid crude product adds the recrystallization mother liquor that example 1 is obtained, add gac 12kg, 70 ℃ of decolouring filtrations in 1 hour down, filtrate is 10 ℃ of crystallizations, through centrifugal, dry white DL-amygdalic acid crystalline product 568kg, the content 99.4% of getting, fusing point: 118.3～119.2 ℃, the product average yield is 88.4%.Recycling Mother Solution is used for above-mentioned recrystallization process.
Embodiment 3:
By embodiment 2 operation that feeds intake, different is that changing into liquid ammonia with weight percent content is 42% sodium hydroxide solution 140kg, mother liquor first filtered while hot after concentrating is removed sodium sulfate, filtrate is cooled to 10 ℃ of following crystallizations then, centrifugation goes out by product ammonium sulfate, the heavy 296kg of dry back producing ammonium sulfate byproduct, content 90%, residual filtrate replaces adding clear water in the hydrolyzing process and recycles, the hydrolyzed solution crystallization gets DL-amygdalic acid crude product 660kg, water content 8% is in butt DL-amygdalic acid content 93%.DL-amygdalic acid reaction average yield is 88.4%.Mother liquor recycles by above-mentioned steps.
In the recrystallization mother liquor that above-mentioned DL-amygdalic acid crude product adding example 2 is obtained, add gac 12kg, 70 ℃ of decolouring filtrations in 1 hour down, filtrate is 10 ℃ of crystallizations, through centrifugal, dry white DL-amygdalic acid crystalline product 542kg, the content 99.2% of getting, fusing point: 117.5-118.2 ℃, the product average yield is 84.2%.Recycling Mother Solution is used for above-mentioned recrystallization process.
Embodiment 4:
In the 500L reactor, add phenyl aldehyde (99%) 200kg, water 200kg, liquid caustic soda (42%) 7kg stirs and is cooled to-15 ℃, and stream adds liquid hydrogen cyanic acid (content 99%) 51.5kg, finishes insulation reaction and finishes in 1 hour.Above-mentioned cyanogenation liquid is gone to the 1000L hydrolysis reactor, be heated to 70～80 ℃, add 31% concentrated hydrochloric acid 295kg, finish insulation reaction and finished in 2 hours.DL-amygdalic acid content in the analytical reaction liquid is 36% (HPLC), adds water 280L, is cooled to 10 ℃ of crystallizations, and is centrifugal, gets DL-amygdalic acid crude product 280kg, and water content 8% is 95% (acid base titration) in butt DL-amygdalic acid content.Mother liquor 690L contains DL-amygdalic acid 50g/L (HPLC) after measured in the mother liquor.Reacting a yield is 86.2%.
Above-mentioned DL-amygdalic acid crude product adds entry 560kg, gac 5kg, 70 ℃ down decolouring filtered in 1 hour, filtrate is 10 ℃ of crystallizations, through centrifugal, dry white DL-amygdalic acid crystalline product 227kg, content 99.4%, fusing point: 118.7～119.2 ℃.Yield 79.5% of product.
Embodiment 5:
In the 500L reactor, add phenyl aldehyde (99%) 200kg, water 200kg, aqueous sodium hydroxide solution (42%) 7kg stirs and is cooled to-15 ℃, and stream adds liquid hydrogen cyanic acid (weight percent content is 80%) 63.7kg, finishes insulation reaction and finishes in 1 hour.Above-mentioned cyanogenation liquid is gone to the 1000L hydrolysis reactor, be heated to 70～80 ℃, add 31% concentrated hydrochloric acid 295kg, finish insulation reaction and finished in 2 hours.DL-amygdalic acid content in the analytical reaction liquid is 36% (HPLC).
In the hydrolysising mother liquid of embodiment 3, add liquid ammonia 11kg, mother liquor behind concentrating under reduced pressure 10 ℃ of following crystallizations, centrifugation goes out side product sodium chloride, the heavy 100kg of dry back by product, content 95.3%, residual filtrate replaces adding in the hydrolyzing process clear water, through repeatedly recycling, the average DL-amygdalic acid crude product 304kg that gets, average moisture content 8% is in butt DL-amygdalic acid content 95%.DL-amygdalic acid reaction average yield is 93.6%.Mother liquor recycles by above-mentioned steps.
Above-mentioned DL-amygdalic acid crude product adds the recrystallization mother liquor that embodiment 3 is obtained, gac 5kg, 70 ℃ of decolouring filtrations in 1 hour down, filtrate is 10 ℃ of crystallizations, through centrifugal, and dry white DL-amygdalic acid crystalline product, get DL-amygdalic acid 258kg, content 99.5%, fusing point: 118.8～119.4 ℃, total yield of products reaches 90.4%.Recycling Mother Solution is used for above-mentioned recrystallization process.
Embodiment 6:
By embodiment 5 operation that feeds intake, different is that liquid ammonia is changed into 18% ammoniacal liquor 65kg, 10 ℃ of following crystallizations, centrifugation goes out side product sodium chloride to mother liquor behind concentrating under reduced pressure, the heavy 100kg of dry back side product sodium chloride, content 96%, residual filtrate replaces adding in the hydrolyzing process clear water, through repeatedly recycling, gets DL-amygdalic acid crude product 310kg, water content 8% is in butt DL-amygdalic acid content 92%.DL-amygdalic acid reaction average yield is 92.4%.Mother liquor recycles by above-mentioned steps.
Above-mentioned DL-amygdalic acid crude product adds the recrystallization mother liquor that example 5 is obtained, gac 5kg, 70 ℃ of decolouring filtrations in 1 hour down, filtrate is 10 ℃ of crystallizations, through centrifugal, and dry white DL-amygdalic acid crystalline product, get DL-amygdalic acid 255kg, content 99%, fusing point: 117.8～118.6 ℃, total yield of products reaches 88.9%.Recycling Mother Solution is used for above-mentioned recrystallization process.
The various embodiments described above are that content of the present invention is further described, but this should be interpreted as that the scope of the above-mentioned theme of the present invention only limits to the foregoing description.All technology that realizes based on foregoing all belong to scope of the present invention.
Claims (10)
1, the preparation method of DL-amygdalic acid is characterized in that comprising the steps:
1), cyaniding: with phenyl aldehyde and acidity or basic catalyst mixing, add water by 0.1～5 times of phenyl aldehyde weight, phenyl aldehyde in molar ratio: prussic acid=1: 0.8～1.5, add weight percent content and be 3～20% prussic acid gas or weight percent content and be 30～100% hydrocyanic acid aqueous solution, the synthetic mandelonitrile of reaction;
2), hydrolysis: above-mentioned mandelonitrile and reaction solution directly add mineral acid without separating, and 30～100 ℃ of hydrolysis, the consumption of mineral acid is 0.5～3 times of mandelonitrile mole number, are formed with the hydrolyzed solution of DL-amygdalic acid and inorganic acid ammonium salt after the hydrolysis fully;
3), crystallization: replenishment cycles mother liquor and/or water in said hydrolyzed liquid, mother liquor that replenishes and/or water yield summation are 0.1～3 times of hydrolyzed solution weight, and then 0～30 ℃ of crystallization, centrifugation obtains DL-amygdalic acid crude product and contains the mother liquor of DL-amygdalic acid crude product inorganic acid ammonium salt;
4), mother liquor is handled: in the above-mentioned mother liquor that contains DL-amygdalic acid crude product and inorganic acid ammonium salt, add inorganic base substance, add-on be in the mother liquor total acid mole number 50～150%, normal pressure or be decompressed to absolute pressure 0～0.09MPa and concentrate the back at 0～30 ℃ of scope intercrystalline, the centrifugal inorganic acid ammonium salt of removing, residue Recycling Mother Solution to hydrolyzing process uses;
5), the DL-amygdalic acid is refining: DL-amygdalic acid crude product is dissolved in water, and amount of water is 1～10 times of DL-amygdalic acid crude product weight, add activated carbon decolorizing by 0.5～8% of crude product weight, filtrate is at 0～30 ℃ of scope intercrystalline, and centrifugal drying gets finished product, and recrystallization mother liquor recycles.
2, the preparation method of DL-amygdalic acid as claimed in claim 1, when it is characterized in that using basic catalyst, temperature of reaction is-20～30 ℃.
3, the preparation method of DL-amygdalic acid as claimed in claim 1 or 2, it is characterized in that basic catalyst is at least a kind of in sodium hydroxide, potassium hydroxide, ammonia, the organic amine, consumption is 0.01～10% of a phenyl aldehyde mole number, and organic amine is Trimethylamine 99 or triethylamine or Diisopropylamine.
4, the preparation method of DL-amygdalic acid as claimed in claim 1, when it is characterized in that using an acidic catalyst, the cyanogenation temperature is 50～100 ℃.
5, as the preparation method of claim 1 or 4 described DL-amygdalic acids, it is characterized in that an acidic catalyst is a kind of in sulfuric acid, hydrochloric acid, phosphoric acid, the oxalic acid, consumption is 0.01～10% of a phenyl aldehyde mole number.
6,, it is characterized in that inorganic base substance is sodium hydroxide or potassium hydroxide or ammonia as the preparation method of claim 1 or 2 or 4 described DL-amygdalic acids.
7, the preparation method of DL-amygdalic acid as claimed in claim 3 is characterized in that inorganic base substance is sodium hydroxide or potassium hydroxide or ammonia.
8, the preparation method of DL-amygdalic acid as claimed in claim 5 is characterized in that inorganic base substance is sodium hydroxide or potassium hydroxide or ammonia.
9,, it is characterized in that mineral acid is at least a kind of in sulfuric acid, hydrochloric acid, the phosphoric acid as the preparation method of claim 1 or 2 or 4 described DL-amygdalic acids.
The preparation method of 10 DL-amygdalic acids as claimed in claim 3 is characterized in that mineral acid is at least a kind of in sulfuric acid, hydrochloric acid, the phosphoric acid.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103102260A (en) * | 2011-11-11 | 2013-05-15 | 山东鲁北药业有限公司 | Novel technology for synthesizing S-mandelic acid |
| CN103880625A (en) * | 2014-04-03 | 2014-06-25 | 重庆紫光国际化工有限责任公司 | Method for preparing D, L-mandelic acid and derivative of D, L-mandelic acid |
| CN103965650A (en) * | 2013-01-31 | 2014-08-06 | 江苏道博化工有限公司 | Disperse red 356 preparation method |
| CN112341361A (en) * | 2020-09-27 | 2021-02-09 | 安徽泰格生物科技有限公司 | Preparation method of mandelonitrile |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61129147A (en) * | 1984-11-27 | 1986-06-17 | Nippon Petrochem Co Ltd | Production of mandelic acid and derivative thereof |
| DE10131810A1 (en) * | 2001-06-30 | 2003-02-27 | Clariant Gmbh | Process for the production of optically active cyanohydrins and their corresponding acids |
-
2005
- 2005-06-21 CN CNB2005100211357A patent/CN100398507C/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103102260A (en) * | 2011-11-11 | 2013-05-15 | 山东鲁北药业有限公司 | Novel technology for synthesizing S-mandelic acid |
| CN103102260B (en) * | 2011-11-11 | 2015-01-21 | 山东鲁北药业有限公司 | Novel technology for synthesizing S-mandelic acid |
| CN103965650A (en) * | 2013-01-31 | 2014-08-06 | 江苏道博化工有限公司 | Disperse red 356 preparation method |
| CN103880625A (en) * | 2014-04-03 | 2014-06-25 | 重庆紫光国际化工有限责任公司 | Method for preparing D, L-mandelic acid and derivative of D, L-mandelic acid |
| CN112341361A (en) * | 2020-09-27 | 2021-02-09 | 安徽泰格生物科技有限公司 | Preparation method of mandelonitrile |
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| CN100398507C (en) | 2008-07-02 |
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