CN103420883A - Method for using crude hydrocyanic acid gas for preparing 2-hydroxy-4-methylmercapto-butyronitrile - Google Patents
Method for using crude hydrocyanic acid gas for preparing 2-hydroxy-4-methylmercapto-butyronitrile Download PDFInfo
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D233/00—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings
- C07D233/54—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings having two double bonds between ring members or between ring members and non-ring members
- C07D233/66—Heterocyclic compounds containing 1,3-diazole or hydrogenated 1,3-diazole rings, not condensed with other rings having two double bonds between ring members or between ring members and non-ring members with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
- C07D233/72—Two oxygen atoms, e.g. hydantoin
- C07D233/76—Two oxygen atoms, e.g. hydantoin with substituted hydrocarbon radicals attached to the third ring carbon atom
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C319/00—Preparation of thiols, sulfides, hydropolysulfides or polysulfides
- C07C319/14—Preparation of thiols, sulfides, hydropolysulfides or polysulfides of sulfides
- C07C319/20—Preparation of thiols, sulfides, hydropolysulfides or polysulfides of sulfides by reactions not involving the formation of sulfide groups
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C323/00—Thiols, sulfides, hydropolysulfides or polysulfides substituted by halogen, oxygen or nitrogen atoms, or by sulfur atoms not being part of thio groups
- C07C323/50—Thiols, sulfides, hydropolysulfides or polysulfides substituted by halogen, oxygen or nitrogen atoms, or by sulfur atoms not being part of thio groups containing thio groups and carboxyl groups bound to the same carbon skeleton
- C07C323/51—Thiols, sulfides, hydropolysulfides or polysulfides substituted by halogen, oxygen or nitrogen atoms, or by sulfur atoms not being part of thio groups containing thio groups and carboxyl groups bound to the same carbon skeleton having the sulfur atoms of the thio groups bound to acyclic carbon atoms of the carbon skeleton
- C07C323/60—Thiols, sulfides, hydropolysulfides or polysulfides substituted by halogen, oxygen or nitrogen atoms, or by sulfur atoms not being part of thio groups containing thio groups and carboxyl groups bound to the same carbon skeleton having the sulfur atoms of the thio groups bound to acyclic carbon atoms of the carbon skeleton with the carbon atom of at least one of the carboxyl groups bound to nitrogen atoms
Abstract
The invention aims at the chemical engineering field, and relates to a method for using crude hydrocyanic acid gas for preparing 2-hydroxy-4-methylmercapto-butyronitrile. Based on the Andrussow method composition principle, the method takes methane, ammonia gas and oxygen gas as raw material to obtain hydrocyanic acid mixed gas I through preparation; the hydrocyanic acid mixed gas I is subjected to deamination treatment to obtain hydrocyanic acid mixed gas II; under the alkaline catalytic action, the hydrocyanic acid mixed gas II is fully reacted with methylmercapto-propionaldehyde to obtain the 2-hydroxy-4-methylmercapto-butyronitrile. The raw material without rectification and purification is adopted for the method and is low in price and easy to get, and the prepared 2-hydroxy-4-methylmercapto-butyronitrile is high in yield and purity. Moreover, an obtained 2-hydroxy-4-methylmercapto-butyronitrilereaction system not purified and separated is stable in property, capable of being stored for a long time and convenient to use in production of down-stream products.
Description
Technical field
The present invention is directed to chemical field, relate to the method for utilizing thick hydrocyanic acid gas to prepare 2-2-hydroxy-4-methylthio butyronitrile.
Background technology
2-2-hydroxy-4-methylthio butyronitrile is to produce D, the important intermediate of L-Methionine or MHA.The yield size of 2-2-hydroxy-4-methylthio butyronitrile and cost drop into, and to the D of final production, quality and the cost of L-Methionine or MHA have material impact.
In theory, the preparation of 2-2-hydroxy-4-methylthio butyronitrile is known, mainly comprises following two kinds of modes:
(1) methylthiopropionaldehyde reacts and makes with prussic acid under the catalysis of alkali;
(2) methylthiopropionaldehyde reacts and makes with alkali metal cyanide under the sodium bisulfite effect.
The disclosed method of US5756803 is a kind of concrete grammar that mode (1) prepares 2-2-hydroxy-4-methylthio butyronitrile.The damping fluid that the method is used citric acid and sodium hydroxide to form is as catalyzer, and the pH of solution is controlled at 4 left and right, and the catalysis methylthiopropionaldehyde reacts with prussic acid, obtains 2-2-hydroxy-4-methylthio butyronitrile.Wherein, prussic acid excessive 2%～5%.The use of buffered soln and excessive prussic acid are conducive to the prolonged preservation of product 2-2-hydroxy-4-methylthio butyronitrile.The 2-2-hydroxy-4-methylthio butyronitrile obtained obtains MHA by mineral acid hydrolysis, or reacts with bicarbonate of ammonia, generates the 5-(2-methylmercaptoethyl)-glycolylurea, the salt of wormwood hydrolysis, the carbonic acid gas neutralization obtains D, L-Methionine.
The disclosed method of US2745745 is a kind of concrete grammar that mode (2) prepares 2-2-hydroxy-4-methylthio butyronitrile.The 2-2-hydroxy-4-methylthio butyronitrile obtained, reaction needs after finishing, with the organic solvent-benzene extraction, to obtain containing 2-2-hydroxy-4-methylthio butyronitrile benzole soln, dry, steaming removes organic solvent-benzene, obtain 2-2-hydroxy-4-methylthio butyronitrile, then with inorganic acid reaction, obtain MHA.
Obviously, in these bibliographical informations, no matter take which kind of mode to synthesize 2-2-hydroxy-4-methylthio butyronitrile, in order to obtain high yield, all need purer prussic acid, and prussic acid is excessive often, the rectifying purifying that prussic acid is extra and excessive use all can cause the increase of cost, the increase of this cost, particularly in technical scale, will cause huge financial loss.Moreover method as disclosed as US2745745, under unsuitable catalyzer is used, may cause the formation of cyaniding byproduct in process thing, and then be that subsequent purification and downstream production make troubles.
For these reasons and prior art, still need further the preparation method of 2-2-hydroxy-4-methylthio butyronitrile is improved.
Summary of the invention
In view of this, the object of the present invention is to provide the method for utilizing thick hydrocyanic acid gas to prepare 2-2-hydroxy-4-methylthio butyronitrile, the raw material that the method is used is cheap and easy to get, the 2-2-hydroxy-4-methylthio butyronitrile yield of preparation is high, purity is high, but its reaction system long-term storage, be convenient to the production for derived product.
For achieving the above object, the technical solution used in the present invention is as follows:
Utilize thick hydrocyanic acid gas to prepare the method for 2-2-hydroxy-4-methylthio butyronitrile, comprise the following steps:
A, take methane, ammonia and oxygen as raw material, adopt iS-One method composition principle, be prepared into prussic acid gas mixture I;
B, prussic acid gas mixture I deamination are processed to obtain prussic acid gas mixture II;
C, prussic acid gas mixture II and methylthiopropionaldehyde, under the katalysis of alkali, fully react to obtain 2-2-hydroxy-4-methylthio butyronitrile.
Wherein, described thick hydrocyanic acid gas just refers to the prussic acid gas mixture standby by iS-One legal system.IS-One method (Andrussow method) is the industrial process completed the 1950's, is the main method of producing prussic acid.The main raw material that it adopts has methane, ammonia and oxygen, therefore be again the methane oxidation proceses of ammonia.This method is under the condition more than normal pressure, l000 ℃, the silk screen that the logical people of material mixed gas is made by platinum, rhodium alloy catalyst platinum and rhodium, or the wire-mesh catalyst bed of being made by platinum iridium alloy, and the oxidative ammonolysis carried out, its reaction formula is 2CH
4+ 2NH
3+ 30
2→ 2HCN+6H
20.At present, this technology is very ripe, and the preparation of special prussic acid synthetic tower for hydrocyanic acid gas arranged.
Described deamination is processed and is referred to that the prussic acid gas mixture I that iS-One legal system is standby passes in acid, sloughs the operation of ammonia.The Main Function that acid rises is absorbing ammonia G&W steam, so preferably sulfuric acid, the sulfuric acid that further preferred concentration is 75%～90%.The prussic acid gas mixture of the present invention before and after deamination is processed all can be used for the preparation of 2-2-hydroxy-4-methylthio butyronitrile, and just the prussic acid gas mixture II character after deamination is processed is more excellent.Industrial, special acid tower can be set and process for deamination.
Further, described prussic acid gas mixture I preferably is comprised of the component of following mass percent: hydrocyanic acid gas 8.8% ± 2%, water vapour 3.9% ± 2%, ammonia 1.6% ± 2%, hydrogen 1.1% ± 2%, nitrogen 76.0% ± 2%, oxygen 1.5% ± 2%, carbon monoxide 5.6% ± 2%, carbonic acid gas 1.1% ± 2%, methane 0.4% ± 2%.Described prussic acid gas mixture II preferably is comprised of the component of following mass percent: hydrocyanic acid gas 9.4% ± 2%, hydrogen 1.6% ± 2%, nitrogen 79.4% ± 2%, oxygen 1.7% ± 2%, carbon monoxide 5.8% ± 2%, carbonic acid gas 1.5% ± 2%, methane 0.6% ± 2%.
Further, described methylthiopropionaldehyde is not purified methylthiopropionaldehyde, wherein containing methylthiopropionaldehyde 94.5%～96%, light constituent 3.5%～5.3% and heavy constituent 0.2%～0.5%; Described light constituent is thiomethyl alcohol, methyl alcohol, propenal and water; Described restructuring is divided into dipolymer and the trimer of methylthiopropionaldehyde.
Further, the preferred 1:1.0 of mol ratio of prussic acid and methylthiopropionaldehyde～1.05 in described step C; Described reaction pressure is 0.09～0.5MPa, and in negative pressure, the environment to malleation can be reacted, for considering of equipment requirements and reaction efficiency, and preferably 0.1～0.3MPa, more preferably 0.1～0.15MPa; Temperature of reaction is 30～80 ℃, preferably 35～60 ℃, and more preferably 40～45 ℃.
Step C is the nucleophilic addition under base catalysis.Further, the alkali of described katalysis is one or more in low-molecular-weight amine compound and mineral alkali; The consumption of the alkali of described katalysis is that the pH that maintains reaction system is 4.0～6.5, and preferably pH is 5.0～5.5.
Described low-molecular-weight amine compound is the aminated compounds of 3～20 carbon atoms preferably, and this compounds can, with methylthiopropionaldehyde arbitrarily than mixing, be conducive to fast reaction speed.The aminated compounds of described 3～20 carbon atoms comprises triethylamine, tri-isopropanolamine, DMA, imidazoles, picoline, pyridine etc., use wherein one or more can, particularly preferably triethylamine and/or pyridine.
Described mineral alkali is one or more in metal hydroxides, metal cyanides, metal carbonate and alkali metal bicarbonate salt.Described metallic hydrogen oxidation compound, as sodium hydroxide or potassium hydroxide; Metal cyanides, as sodium cyanide or potassium cyanide; Metal carbonate, as sodium carbonate or salt of wormwood; Alkali metal bicarbonate salt, as sodium bicarbonate or saleratus.Independent a kind of mineral alkali or mixed base can.
Further, also add acid in the alkali of described katalysis, form mixture or the damping fluid of bronsted lowry acids and bases bronsted lowry; Described acid comprises mineral acid and organic acid.Adding or the formation of damping fluid of acid, can make reaction system maintain in more stable pH value scope.Described organic acid is a kind of in acetic acid, formic acid, citric acid, Phenylsulfonic acid and trifluoromethanesulfonic acid; Described mineral acid is sulfuric acid or phosphoric acid.The damping fluid that forms is as Trisodium Citrate-sodium hydrate buffer solution, sodium succinate-sodium hydrate buffer solution, acetic acid-sodium hydrate buffer solution etc., optimization citric acid-sodium hydrate buffer solution.
Another object of the present invention is to provide the method for utilizing 2-2-hydroxy-4-methylthio butyronitrile production equipment to prepare 2-2-hydroxy-4-methylthio butyronitrile, the method equipment is simple, and controllability is strong, is applicable to the industrially scalable application.
Its technical scheme is as follows:
Utilize 2-2-hydroxy-4-methylthio butyronitrile production equipment to prepare the method for 2-2-hydroxy-4-methylthio butyronitrile, described 2-2-hydroxy-4-methylthio butyronitrile production equipment comprises prussic acid synthetic tower, acid tower and reactor, fill 75%～90% sulfuric acid in described acid tower, described reactor is provided with pressure and temperature regulation supplementary unit, the air outlet of prussic acid synthetic tower is communicated with the inlet mouth of acid tower by pipeline, and the air outlet of acid tower is communicated with reactor by the pipeline that is provided with throttling valve;
A, take methane, ammonia and oxygen as raw material, adopt iS-One method composition principle, by the prussic acid synthetic tower, prepare prussic acid gas mixture I;
B, prussic acid gas mixture I pass into acid tower and slough ammonia and water vapour, obtain prussic acid gas mixture II;
C, prussic acid gas mixture II, under throttle valve control, pass in the methylthiopropionaldehyde in reactor with the speed of 250～350L/min, under the katalysis of alkali, fully react to obtain 2-2-hydroxy-4-methylthio butyronitrile.
The present invention also has a purpose to be to provide the reaction system of 2-2-hydroxy-4-methylthio butyronitrile, and this reaction system stable in properties, can long-term storage.
The reaction system of this 2-2-hydroxy-4-methylthio butyronitrile is not carried out the system of separation and purification after being reaction, and the 2-2-hydroxy-4-methylthio butyronitrile obtained by following reactions steps forms together with its reaction solution:
A, take methane, ammonia and oxygen as raw material, adopt iS-One method composition principle, be prepared into prussic acid gas mixture I;
B, prussic acid gas mixture I deamination are processed to obtain prussic acid gas mixture II;
C, prussic acid gas mixture II and methylthiopropionaldehyde, under the katalysis of alkali, fully react to obtain 2-2-hydroxy-4-methylthio butyronitrile.
In described system except containing the 2-2-hydroxy-4-methylthio butyronitrile made, the prussic acid that also to contain remaining massfraction be 0.05%～0.5% and 2%～5% water.Just because of the existence of residual hydrogen cyanic acid and water, but the 2-2-hydroxy-4-methylthio butyronitrile long-term storage in this reaction system and decomposing hardly.
Further, this reaction system is adjusted to pH with acid and 2～4 is deposited.Like this, even still keep at normal temperatures longer stability.The acid of described adjusting pH can be sulfuric acid, phosphoric acid etc., concentration preferably 85%.
Described 2-2-hydroxy-4-methylthio butyronitrile reaction system, without carrying out any separation and purification, can be directly used in the production of derived product, again due to its can be steady in a long-term preservation, be particularly suitable for D, the production of L-Methionine and 2-hydroxy-4-(methylthio) base butyric acid.
Useful technique effect of the present invention is:
(1) adopt standby thick hydrocyanic acid gas and the not purified methylthiopropionaldehyde of iS-One legal system, raw material, without the rectifying purifying, is saved the production time, has improved production efficiency, has also reduced production cost; Prepare 2-2-hydroxy-4-methylthio butyronitrile by the method, yield is more than 99%, and purity is more than 96%.
(2) utilize 2-2-hydroxy-4-methylthio butyronitrile production equipment to prepare the method for 2-2-hydroxy-4-methylthio butyronitrile, the equipment related to is simple, and controllability is strong, is applicable to the industrially scalable application.
(3) the 2-2-hydroxy-4-methylthio butyronitrile reaction system prepared, confirm through experiment, stable in properties, but long-term storage, and do not need to carry out separation and purification, can be directly used in the production of derived product.
The accompanying drawing explanation
The structural representation that Fig. 1 is 2-2-hydroxy-4-methylthio butyronitrile production equipment.
Embodiment
Hereinafter with reference to accompanying drawing, the preferred embodiments of the present invention are described in detail.The experimental technique of unreceipted actual conditions in preferred embodiment, carry out according to normal condition.
Embodiment 1
To from the prussic acid synthetic tower, prussic acid gas mixture I is out detected, the consisting of of prussic acid gas mixture I: hydrocyanic acid gas 8.87%, water vapour 3.88%, ammonia 1.64%, hydrogen 1.13%, nitrogen 76.01%, oxygen 1.48%, carbon monoxide 5.67%, carbonic acid gas 1.13%, methane 0.39%.
Prussic acid gas mixture I after 75% sulfuric acid tower absorbs the ammonia and water vapour thereof in gas mixture, the consisting of of the prussic acid gas mixture II obtained: hydrocyanic acid gas 9.35%, hydrogen 1.57%, nitrogen 79.44%, oxygen 1.71%, carbon monoxide 5.79%, carbonic acid gas 1.50%, methane 0.64%.
Embodiment 2
Prussic acid gas mixture II is passed in the methylthiopropionaldehyde of 223.3g94.5%, contain the 3.3g pyridine in methylthiopropionaldehyde.Under normal pressure, react, controlling temperature of reaction is 45 ℃, and draft speed is 300L/min, and tail gas absorbs with sodium hydroxide, with the residual volume of HPLC monitoring methylthiopropionaldehyde.When the methylthiopropionaldehyde residual volume is less than 0.5%, be reaction end, can stop passing into.Be total to obtain weak yellow liquid 270.64g, the content of 2-2-hydroxy-4-methylthio butyronitrile is 98%, prussic acid remnants 0.5%.The 2-2-hydroxy-4-methylthio butyronitrile obtained is divided into to two parts together with reaction solution (being 2-2-hydroxy-4-methylthio butyronitrile reaction system).Portion wherein adds 8.5g water, under 3 ℃ of conditions, preserves 120 days, has no decomposition; Another part adds 8.5g water wherein, with 85% sulfuric acid acidation, to pH, is then 3, and under 20 ℃ of conditions, preservation is 120 days, and 2-2-hydroxy-4-methylthio butyronitrile rate of decomposition is 0.1%.
Embodiment 3
Prussic acid gas mixture II is passed in the methylthiopropionaldehyde of 223.3g94.5%, contain the water of 2.2g pyridine and 10g in methylthiopropionaldehyde.Under 0.15MPa, controlling temperature of reaction is 42 ℃, and draft speed is 280L/min, and tail gas absorbs with sodium hydroxide, with the residual volume of HPLC monitoring methylthiopropionaldehyde.When the methylthiopropionaldehyde residual volume is less than 0.5%, be reaction end, can stop passing into.Be total to obtain weak yellow liquid 279.54g, the content of 2-2-hydroxy-4-methylthio butyronitrile is 98%, prussic acid remnants 0.07%.The 2-2-hydroxy-4-methylthio butyronitrile obtained is divided into to two parts together with reaction solution.Portion is wherein preserved 120 days under 3 ℃ of conditions, has no decomposition; The sulfuric acid acidation of another part of use 85% is 3 to pH, and under 20 ℃ of conditions, preservation is 130 days, and 2-2-hydroxy-4-methylthio butyronitrile rate of decomposition is 0.3%.
Embodiment 4
Prussic acid gas mixture II is passed in the methylthiopropionaldehyde of 247.2g94.5%, contain the water of 2.2g pyridine and 15g in methylthiopropionaldehyde.Under 0.5MPa, controlling temperature of reaction is 45 ℃, and draft speed is 280L/min, and tail gas absorbs with sodium hydroxide, with the residual volume of HPLC monitoring methylthiopropionaldehyde.When the methylthiopropionaldehyde residual volume is less than 0.5%, be reaction end, can stop passing into.Be total to obtain weak yellow liquid 294.54g, the content of 2-2-hydroxy-4-methylthio butyronitrile is 98%, prussic acid remnants 0.07%.The 2-2-hydroxy-4-methylthio butyronitrile obtained is divided into to two parts together with reaction solution.Portion is wherein preserved 120 days under 3 ℃ of conditions, has no decomposition; It is 3 that the phosphoric acid of another part of use 85% is acidified to pH, under 20 ℃ of conditions, preserves 128 days, and 2-2-hydroxy-4-methylthio butyronitrile rate of decomposition is 0.2%.
Embodiment 5
Prussic acid gas mixture II is passed in the methylthiopropionaldehyde of 227.3g94.5%, contain the water of 3.3g pyridine and 4g in methylthiopropionaldehyde.Under 0.09MPa, controlling temperature of reaction is 80 ℃, and draft speed is 350L/min, and tail gas carries out burning disposal, and incineration temperature is higher than 1000 ℃.With the residual volume of HPLC monitoring methylthiopropionaldehyde, when the methylthiopropionaldehyde residual volume is less than 0.5%, be reaction end, can stop passing into.Be total to obtain weak yellow liquid 277.4g, the content of 2-2-hydroxy-4-methylthio butyronitrile is 97%, prussic acid remnants 0.06%, moisture content 2%.The 2-2-hydroxy-4-methylthio butyronitrile obtained is divided into to two parts together with reaction solution.Portion is wherein preserved 120 days under 3 ℃ of conditions, has no decomposition; Another part of use 85% sulfuric acid acidation is 2 to pH, and under 23 ℃ of conditions, preservation is 120 days, and 2-2-hydroxy-4-methylthio butyronitrile rate of decomposition is 0.1%.
Embodiment 6
Prussic acid gas mixture II is passed in the methylthiopropionaldehyde of 237.3g94.5%, contain 8.5g water in methylthiopropionaldehyde, in mixed system, add a certain amount of catalyzer carbonic acid sodium, keeping the pH of system in passing into prussic acid gas mixture process is 5.5.Under 0.5MPa, controlling temperature of reaction is 30 ℃, and draft speed is 350L/min, and tail gas carries out burning disposal, and incineration temperature is higher than 1000 ℃.With the residual volume of HPLC monitoring methylthiopropionaldehyde, when the methylthiopropionaldehyde residual volume is less than 0.5%, be reaction end, can stop passing into.Be total to obtain weak yellow liquid 287.4g, the content of 2-2-hydroxy-4-methylthio butyronitrile is 96%, prussic acid remnants 0.06%, moisture content 3%.The 2-2-hydroxy-4-methylthio butyronitrile obtained is divided into to two parts together with reaction solution.Portion is wherein preserved 120 days under 3 ℃ of conditions, has no decomposition; Another part of use 85% sulfuric acid acidation is 2 to pH, and under 23 ℃ of conditions, preservation is 120 days, and 2-2-hydroxy-4-methylthio butyronitrile rate of decomposition is 0.1%.
Embodiment 7
Prussic acid gas mixture II is passed in the methylthiopropionaldehyde of 233.3g94.5%, contain 8.5g water in methylthiopropionaldehyde, in mixed system, add a certain amount of catalyst of triethylamine, keeping the pH of system in passing into prussic acid gas mixture process is 5.5.Under normal pressure, react, controlling temperature of reaction is 40 ℃, and draft speed is 350L/min, and tail gas carries out burning disposal, and incineration temperature is higher than 1000 ℃.With the residual volume of HPLC monitoring methylthiopropionaldehyde, when the methylthiopropionaldehyde residual volume is less than 0.5%, be reaction end, can stop passing into.Be total to obtain weak yellow liquid 287.4g, the content of 2-2-hydroxy-4-methylthio butyronitrile is 96%, prussic acid remnants 0.06%, moisture content 3%.The 2-2-hydroxy-4-methylthio butyronitrile obtained is divided into to two parts together with reaction solution.Portion is wherein preserved 120 days under 3 ℃ of conditions, has no decomposition; Another part of use 75% sulfuric acid acidation is 2 to pH, and under 23 ℃ of conditions, preservation is 120 days, and 2-2-hydroxy-4-methylthio butyronitrile rate of decomposition is 0.1%.
Embodiment 8
Prussic acid gas mixture II is passed in the methylthiopropionaldehyde of 223.3g94.5%, and to the damping fluid that adds in mixed system a certain amount of sodium hydroxide and citric acid to form, keeping the pH of system in logical prussic acid gas mixture process is 5.0.Under normal pressure, react, controlling temperature of reaction is 45 ℃, and draft speed is 350L/min, and tail gas carries out burning disposal, and incineration temperature is higher than 1000 ℃.With the residual volume of HPLC monitoring methylthiopropionaldehyde, when the methylthiopropionaldehyde residual volume is less than 0.5%, be reaction end, can stop passing into.Be total to obtain weak yellow liquid 287.4g, the content of 2-2-hydroxy-4-methylthio butyronitrile is 97%, prussic acid remnants 0.06%, moisture content 2%.The 2-2-hydroxy-4-methylthio butyronitrile obtained is divided into to two parts together with reaction solution.Portion is wherein preserved 120 days under 3 ℃ of conditions, has no decomposition; Another part of use 90% sulfuric acid acidation is 3 to pH, and under 23 ℃ of conditions, preservation is 120 days, and 2-2-hydroxy-4-methylthio butyronitrile rate of decomposition is 0.1%.
Embodiment 9
Take the bicarbonate of ammonia of 4mol, add the 1500g water dissolution, under room temperature, the 2-2-hydroxy-4-methylthio butyronitrile reaction system of embodiment 2 preparations is all added in ammonium bicarbonate aqueous solution and stirred.Mixed solution is poured in the four-hole round-bottomed flask of 2000 milliliters, be warming up to immediately 80 ℃, normal pressure heat-insulating stirs 2 hours.After stopped reaction, add the 1.74g gac to be decoloured, the filter activity charcoal, filtrate is poured in the beaker of 2000 milliliters, static, be cooled to 3 ℃, separate out a large amount of white solids, suction filtration, oven dry, obtain the 5-(2-methylmercaptoethyl)-glycolylurea 348g, purity 99%, yield 99%.Obtain filtrate 1585g, wherein the 5-(2-methylmercaptoethyl)-content of glycolylurea is 0.2%.The 5-(2-methylmercaptoethyl obtained)-glycolylurea can be further used for D, the preparation of L-Methionine.
Embodiment 10
As shown in Figure 1, the production equipment of 2-2-hydroxy-4-methylthio butyronitrile, comprise prussic acid synthetic tower 1, acid tower 2 and reactor 3, fill 75%～90% sulfuric acid in described acid tower 2, described reactor 3 is provided with pressure and temperature regulation supplementary unit, the air outlet of prussic acid synthetic tower 1 is communicated with the inlet mouth of acid tower 2 by pipeline, and the air outlet of acid tower 2 is communicated with reactor 3 by the pipeline that is provided with throttling valve.
According to the synthetic prussic acid requirement of iS-One method, send into raw material to prussic acid synthetic tower 1, react to obtain prussic acid gas mixture I; Prussic acid gas mixture I passes into acid tower 2 and sloughs ammonia and water vapour, obtains prussic acid gas mixture II; Prussic acid gas mixture II, under throttle valve control, passes in the methylthiopropionaldehyde of 225kg94.5% in reactor 3 with the speed of 300L/min, contains the 3.3kg pyridine in methylthiopropionaldehyde.Under normal pressure, react, controlling temperature of reaction is 45 ℃, and tail gas absorbs with sodium hydroxide, with the residual volume of HPLC monitoring methylthiopropionaldehyde.When the methylthiopropionaldehyde residual volume is less than 0.5%, be reaction end, can stop passing into.Be total to obtain weak yellow liquid 271.3kg, the content of 2-2-hydroxy-4-methylthio butyronitrile is 98%, prussic acid remnants 0.5%.The 2-2-hydroxy-4-methylthio butyronitrile obtained is divided into to two parts together with reaction solution (being 2-2-hydroxy-4-methylthio butyronitrile reaction system).Portion wherein adds 8.5kg water, under 3 ℃ of conditions, preserves 120 days, has no decomposition; Another part adds 8.5kg water wherein, with 85% sulfuric acid acidation, to pH, is then 3, and under 20 ℃ of conditions, preservation is 120 days, and 2-2-hydroxy-4-methylthio butyronitrile rate of decomposition is 0.1%.
Finally explanation is, above embodiment is only unrestricted in order to technical scheme of the present invention to be described, those of ordinary skill in the art is to be understood that, can modify or be equal to replacement technical scheme, and not breaking away from aim and the scope of technical solution of the present invention, it all should be encompassed in the middle of claim scope of the present invention.
Claims (10)
1. utilize thick hydrocyanic acid gas to prepare the method for 2-2-hydroxy-4-methylthio butyronitrile, it is characterized in that: comprise the following steps:
A, take methane, ammonia and oxygen as raw material, adopt iS-One method composition principle, be prepared into prussic acid gas mixture I;
B, described prussic acid gas mixture I deamination are processed to obtain prussic acid gas mixture II;
C, described prussic acid gas mixture II and methylthiopropionaldehyde, under the katalysis of alkali, fully react to obtain 2-2-hydroxy-4-methylthio butyronitrile.
2. the method for preparing 2-2-hydroxy-4-methylthio butyronitrile according to claim 1, it is characterized in that: step B passes into by described prussic acid gas mixture I the sulfuric acid that concentration is 75%～90% to carry out the deamination processing.
3. the method for preparing 2-2-hydroxy-4-methylthio butyronitrile according to claim 1, it is characterized in that: described methylthiopropionaldehyde is not purified methylthiopropionaldehyde, wherein containing methylthiopropionaldehyde 94.5%～96%, light constituent 3.5%～5.3% and heavy constituent 0.2%～0.5%; Described light constituent is thiomethyl alcohol, methyl alcohol, propenal and water; Described restructuring is divided into dipolymer and the trimer of methylthiopropionaldehyde.
4. the method for preparing 2-2-hydroxy-4-methylthio butyronitrile according to claim 1, it is characterized in that: the mol ratio of prussic acid described in step C and methylthiopropionaldehyde is 1:1.0～1.05, and reaction pressure is 0.09～0.5MPa, and temperature of reaction is 30～80 ℃.
5. the method for preparing 2-2-hydroxy-4-methylthio butyronitrile according to claim 1 is characterized in that: the aminated compounds that the alkali of described katalysis is 3～20 carbon atoms and one or more in mineral alkali; The consumption of the alkali of described katalysis is that the pH that maintains reaction system is 4.0～6.5.
6. the method for preparing 2-2-hydroxy-4-methylthio butyronitrile according to claim 5, it is characterized in that: the aminated compounds of described 3～20 carbon atoms is one or more in triethylamine, tri-isopropanolamine, DMA, imidazoles, picoline and pyridine.
7. the method for preparing 2-2-hydroxy-4-methylthio butyronitrile according to claim 5, it is characterized in that: described mineral alkali is one or more in metal hydroxides, metal cyanides, metal carbonate and alkali metal bicarbonate salt.
8. according to the described method for preparing 2-2-hydroxy-4-methylthio butyronitrile of claim 5 to 7 any one, it is characterized in that: also add acid in the alkali of described katalysis, form mixture or the damping fluid of bronsted lowry acids and bases bronsted lowry; Described acid comprises mineral acid and organic acid; Described organic acid is a kind of in acetic acid, formic acid, citric acid, Phenylsulfonic acid and trifluoromethanesulfonic acid; Described mineral acid is sulfuric acid or phosphoric acid.
9. utilize 2-2-hydroxy-4-methylthio butyronitrile production equipment to prepare the method for 2-2-hydroxy-4-methylthio butyronitrile, it is characterized in that: described 2-2-hydroxy-4-methylthio butyronitrile production equipment comprises prussic acid synthetic tower (1), acid tower (2) and reactor (3), described acid tower fills 75%～90% sulfuric acid in (2), described reactor (3) is provided with pressure and temperature regulation supplementary unit, the air outlet of prussic acid synthetic tower (1) is communicated with the inlet mouth of acid tower (2) by pipeline, and the air outlet of acid tower (2) is communicated with reactor (3) by the pipeline that is provided with throttling valve;
A, take methane, ammonia and oxygen as raw material, adopt iS-One method composition principle, by prussic acid synthetic tower (1), prepare prussic acid gas mixture I;
B, described prussic acid gas mixture I pass into acid tower (2) and slough ammonia and water vapour, obtain prussic acid gas mixture II;
C, described prussic acid gas mixture II, under throttle valve control, pass in the methylthiopropionaldehyde in reactor (3) with the speed of 250～350L/min, under the katalysis of alkali, fully react to obtain 2-2-hydroxy-4-methylthio butyronitrile.
10.2-the reaction system of 2-hydroxy-4-methylthio butyronitrile is characterized in that: the 2-2-hydroxy-4-methylthio butyronitrile obtained by following reactions steps forms together with its reaction solution:
A, take methane, ammonia and oxygen as raw material, adopt iS-One method composition principle, be prepared into prussic acid gas mixture I;
B, described prussic acid gas mixture I deamination are processed to obtain prussic acid gas mixture II;
C, described prussic acid gas mixture II and methylthiopropionaldehyde, under the katalysis of alkali, fully react to obtain 2-2-hydroxy-4-methylthio butyronitrile.
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| CN2013103817151A CN103420883A (en) | 2013-08-28 | 2013-08-28 | Method for using crude hydrocyanic acid gas for preparing 2-hydroxy-4-methylmercapto-butyronitrile |
| CN201310721668.0A CN103694177B (en) | 2013-08-28 | 2013-12-24 | Hydrocyanic acid gaseous mixture is utilized to produce 5-(2-methylmercaptoethyl continuously) method of-hydantoin and device thereof |
| CN201310722404.7A CN103724242B (en) | 2013-08-28 | 2013-12-24 | Hydrocyanic acid gaseous mixture is utilized to produce D, the method for METHIONINE salt and device thereof continuously |
| CN201310722863.5A CN103664719B (en) | 2013-08-28 | 2013-12-24 | Thick hydrocyanic acid is utilized to produce D continuously, the method for METHIONINE and device |
| CN201310721634.1A CN103664718B (en) | 2013-08-28 | 2013-12-24 | Utilize thick prussic acid continuous seepage D, the method for L-2-hydroxy-4-methylthiobutyric acid microelement chelate and device thereof |
| CN201310722890.2A CN103755608B (en) | 2013-08-28 | 2013-12-24 | Thick hydrocyanic acid is utilized to produce method and the device thereof of D, L-2-2-hydroxy-4-methylthio calcium butyrate continuously |
| CN201310722698.3A CN103664720A (en) | 2013-08-28 | 2013-12-24 | Method for using hydrocyanic acid mixed gas to prepare 2-hydroxy-4-methylthio-butyronitrile and continuous production method for 2-hydroxy-4-methylthio-butyronitrile |
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| CN201310721668.0A Active CN103694177B (en) | 2013-08-28 | 2013-12-24 | Hydrocyanic acid gaseous mixture is utilized to produce 5-(2-methylmercaptoethyl continuously) method of-hydantoin and device thereof |
| CN201310722404.7A Active CN103724242B (en) | 2013-08-28 | 2013-12-24 | Hydrocyanic acid gaseous mixture is utilized to produce D, the method for METHIONINE salt and device thereof continuously |
| CN201310721634.1A Active CN103664718B (en) | 2013-08-28 | 2013-12-24 | Utilize thick prussic acid continuous seepage D, the method for L-2-hydroxy-4-methylthiobutyric acid microelement chelate and device thereof |
| CN201310722698.3A Pending CN103664720A (en) | 2013-08-28 | 2013-12-24 | Method for using hydrocyanic acid mixed gas to prepare 2-hydroxy-4-methylthio-butyronitrile and continuous production method for 2-hydroxy-4-methylthio-butyronitrile |
| CN201310722863.5A Active CN103664719B (en) | 2013-08-28 | 2013-12-24 | Thick hydrocyanic acid is utilized to produce D continuously, the method for METHIONINE and device |
| CN201310722890.2A Active CN103755608B (en) | 2013-08-28 | 2013-12-24 | Thick hydrocyanic acid is utilized to produce method and the device thereof of D, L-2-2-hydroxy-4-methylthio calcium butyrate continuously |
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| CN201310722404.7A Active CN103724242B (en) | 2013-08-28 | 2013-12-24 | Hydrocyanic acid gaseous mixture is utilized to produce D, the method for METHIONINE salt and device thereof continuously |
| CN201310721634.1A Active CN103664718B (en) | 2013-08-28 | 2013-12-24 | Utilize thick prussic acid continuous seepage D, the method for L-2-hydroxy-4-methylthiobutyric acid microelement chelate and device thereof |
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| CN201310722890.2A Active CN103755608B (en) | 2013-08-28 | 2013-12-24 | Thick hydrocyanic acid is utilized to produce method and the device thereof of D, L-2-2-hydroxy-4-methylthio calcium butyrate continuously |
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| CN103664720A (en) | 2014-03-26 |
| CN103664719B (en) | 2016-06-08 |
| CN103724242A (en) | 2014-04-16 |
| CN103694177A (en) | 2014-04-02 |
| CN103664719A (en) | 2014-03-26 |
| CN103755608B (en) | 2016-06-08 |
| CN103694177B (en) | 2017-01-04 |
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| CN103664718B (en) | 2016-03-30 |
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| CN103755608A (en) | 2014-04-30 |
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