A kind of isobutyric manufacture method
The present invention relates to a kind of isobutyric manufacture method, particularly relating to a kind of is that raw material is produced isobutyric processing method with the isobutyric aldehyde.
Isopropylformic acid has widespread use as flavouring agent, medicine and fine chemical material, and its preparation method can be divided into Isobutyraldehyde process and isopropylcarbinol oxidation style, oxygenant available air or oxygen by raw material sources.Alcohol oxidation style product yield is low, and productive rate only is 73%~76%, and the production cost height, by product is more, three wastes treatment capacity is big, and applying of its technology is restricted.Isobutyraldehyde oxidation method product selectivity height, technological process is simple, is the isopropylformic acid manufacture method that generally adopts at present.
It is less to prepare isobutyric method report about the isobutyric aldehyde oxidation step, Japanese Patent JP 4-108758 discloses a kind of manufacture method of carboxylic acid: under the katalysis of nickel compound, contain the aldehyde cpd and the oxygen-containing gas reaction of straight or branched alkyl, aromatic base, generate corresponding carboxylic acid.The catalyzer that is adopted is the polyoxy heterogeneous ring compound of a class complexity, the nickeliferous heterogeneous ring compound complex structure of this class, and synthetic difficulty, and cost an arm and a leg, use as commercial catalysts, will cause production cost to increase.U.S. Pat 5,068,366 have introduced coproduction oxidation iso-butylene and isobutyric synthetic method.This reaction adopts the straight-chain carboxylic acid's salt such as the Cobaltous diacetate of variable valency metals such as cobalt, manganese, iron, copper to make catalyzer, under the dichlorobenzene solvent action, 20~180 ℃ of temperature of reaction, reaction times 4h makes isobutylene oxidation thing and isopropylformic acid by iso-butylene and the common oxidation of isobutyric aldehyde.As the coproduction product, isobutyric yield is very low, and the highest have only 12.5%.
The objective of the invention is, provide a kind of that be suitable for that industrial production is used and catalytic effect is good, adopt isobutyric aldehyde to make isobutyric novel method as the raw material oxidation.Another object of the present invention is a catalyzer cheap and easy to get by adopting, that toxicity is little, can under the reaction conditions of gentleness, react, and the product selectivity height, production cost is low, thereby improves competitiveness of product.
In order to achieve the above object, the present invention proposes following isobutyric manufacture method:
In the plastics bubble tower or reactor of stainless steel, lass lining or organic solvent-resistant, add isobutyric aldehyde and mixture of catalysts, in the presence of oxygen-containing gas and/or solvent, reaction generates isopropylformic acid.Reaction can be carried out in the presence of solvent, also can tap into capable oxidizing reaction.The solvent that is adopted is generally isopropylformic acid, acetic acid, propionic acid, butanic acid etc.These solvents both may be used alone, can also be used in combination.Especially isopropylformic acid helps obtaining high product yield, does not have separation problem simultaneously.The quality compositing range of isobutyric aldehyde is 5%~99.5% in the general reaction raw materials, and the quality compositing range of solvent is 95%~0.5%.
The catalyzer that reaction is used can be the straight or branched carboxylate salt of manganese metal, cobalt, copper etc., as isobutyrate, acetate or butanic acid salt, good catalytic activity be the isobutyrate of this metalloid, preferred isopropylformic acid manganese.Also two kinds of materials wherein can be made composite catalyzer, the representative isopropylformic acid enumerated manganese and isopropylformic acid copper, isopropylformic acid manganese and neutralized verdigris, manganese acetate and Cobaltous diacetate, isopropylformic acid manganese and butanic acid cobalt etc. with any than the mixture of forming.These catalyzer can be obtained with any method, do not have special restriction, and are also passable with what sell on the market.
In the present invention, suitable catalyzer add-on is 0.005%~5.0% (wt) of material total amount, improves catalyst consumption, helps the carrying out of oxidizing reaction.But catalyst levels is too many, and production cost improves first, second easily causes deep oxidation and causes product selectivity to descend.Be preferably 0.05%~3.0% (wt), preferred 0.05%~1.0% (wt).
In bubble tower or tank reactor, temperature of reaction is controlled in 0~50 ℃ of scope, and temperature of reaction is 20~40 ℃ preferably; React (20~30 ℃) under the room temperature, speed of response is fast at this moment, reaction yield is high, reaches reaction effect preferably.
The system pressure of reaction is 0~2.0MPa (absolute pressure), and reaction pressure improves, and dissolved oxygen speeds up, and the isobutyric aldehyde transformation efficiency raises.Pressure does not have influence substantially to the selectivity of reaction.
Being used for oxygen-containing gas of the present invention can be oxygen, air or oxygen and the mixture that reaction is inert gasses.In 30~600 minutes, feed the oxygen oxygen-containing gas of equivalent oxygen (or contain) of 0.5~2.0 times of theoretical amount, can keep speed of response and reaction yield preferably.
In the present invention, oxygen or oxygen-containing gas are fed by bubble tower or reactor bottom, are divided into bubble in small, broken bits through gas distributor, can increase the gas-to-liquid contact area like this, improve gas effciency.Reaction mass, is injected by bubble tower or reactor top after the outer water cooler cooling of process by bubble tower or the extraction of reactor bottom through pump again in reaction process, thereby forms the outer circulation of reaction mass.Outer circulation rises stirs and condensation, the selectivity of control reaction temperature and product effectively.The total overall reaction material at 1~10 minute internal recycle once.
Reaction of the present invention both can be carried out in liquid phase continuously, also can carry out in the gap.Adopt isobutyric manufacture method disclosed in this invention, the transformation efficiency of isobutyric aldehyde is greater than 99.5%, and isobutyric selectivity reaches more than 90%.
The isobutyric synthesis technique that the present invention proposes adopts isobutyrate catalyzer cheap and easy to get, catalytic efficiency height not only, thus improved isobutyric selectivity; And do not introduce other impurity, easily separate with product.On the other hand, reaction is at room temperature carried out, and reaction heat can shift out by outer circulation and water coolant, needn't adopt low temperature control system, and facility investment is less, and energy consumption reduces.Whole process flow is simple, and the product yield height is easy to industry and promotes.
In order more specifically to describe technical scheme of the present invention, be described further below in conjunction with embodiment, but the present invention is not limited to these embodiment.
Embodiment 1
At internal diameter is to add 150 gram isobutyric aldehydes, 0.2 gram isopropylformic acid manganese in the stainless steel bubbling tower of 20mm, high 750mm.To 0.3MPa, in 180 minutes, at the uniform velocity feed 99.8 gram oxygen with the nitrogen punching press.Reaction mass carries out outer circulation with the speed of 82ml/min in reaction process, and keeping temperature of reaction is 20~30 ℃, and reaction heat can shift out by outer circulation and water coolant, and afterreaction finished in 180 minutes.Through gas chromatographic analysis, the isobutyric aldehyde transformation efficiency is 99.5%, and the isopropylformic acid selectivity is 91.9%.
Embodiment 2
Employing is with the same bubbling column reactor of embodiment 1.Add 100 gram isobutyric aldehydes, 0.2 gram manganese acetate.To 0.2MPa, in 200 minutes, at the uniform velocity feed 24.7 gram oxygen and 123.5 gram air with the nitrogen punching press.Reaction mass carries out outer circulation with the speed of 82ml/min in reaction process, and the maintenance temperature of reaction is 20~30 ℃.Afterreaction finished in 200 minutes.Analyze through vapor-phase chromatography, drawing the isobutyric aldehyde transformation efficiency is 99.4%, and the isopropylformic acid selectivity is 90.1%.
Embodiment 3
Employing is with the same bubbling column reactor of embodiment 1.Add 150 gram isobutyric aldehydes, 0.4 gram neutralized verdigris.To 0.2MPa, in 180 minutes, at the uniform velocity feed 99.8 gram oxygen and 86.6 gram nitrogen with the nitrogen punching press.Reaction mass carries out outer circulation with the speed of 82ml/min in reaction process, 30~40 ℃.Afterreaction finished in 180 minutes.Analyze through vapor-phase chromatography, drawing the isobutyric aldehyde transformation efficiency is 99.4%, and the isopropylformic acid selectivity is 90.3%.
Embodiment 4
Employing is with the same bubbling column reactor of embodiment 1.Add 150 gram isobutyric aldehydes, 0.1 gram isopropylformic acid manganese.Normal pressure at the uniform velocity fed 267 gram air in 400 minutes.Reaction mass carries out outer circulation with the speed of 82ml/min in reaction process.Temperature of reaction is 20~40 ℃, 400 minutes reaction times.Through sampling analysis, drawing the isobutyric aldehyde transformation efficiency is 98.6%, and the isopropylformic acid selectivity is 92.3%.
Embodiment 5
Employing is with the same bubbling column reactor of embodiment 1.Add 150 gram isobutyric aldehydes, 1.5 gram isopropylformic acid manganese.To 0.3MPa, in 180 minutes, at the uniform velocity feed 80 gram oxygen with the nitrogen punching press.Reaction mass carries out outer circulation with the speed of 82ml/min in reaction process, and temperature of reaction is 20~40 ℃, 180 minutes reaction times.Through sampling analysis, drawing the isobutyric aldehyde transformation efficiency is 99.1%, and the isopropylformic acid selectivity is 91.7%.
Embodiment 6
Employing is with the same bubbling column reactor of embodiment 1.Add 150 gram isobutyric aldehydes, 0.08 gram manganese acetate and 0.08 gram neutralized verdigris.To 0.3MPa, in 240 minutes, at the uniform velocity feed 88 gram oxygen with the nitrogen punching press.Reaction mass carries out outer circulation with the speed of 170ml/min in reaction process, and temperature of reaction is 20~30 ℃, 240 minutes reaction times.Through sampling analysis, drawing the isobutyric aldehyde transformation efficiency is 99.5%, and the isopropylformic acid selectivity is 93.3%.
Embodiment 7
Employing is with the same bubbling column reactor of embodiment 1.Add 100 gram isobutyric aldehydes, 0.013 gram isopropylformic acid manganese and 0.013 gram isopropylformic acid copper.With nitrogen punching press 0.3MPa, in 180 minutes, at the uniform velocity feed 44.6 gram oxygen.Reaction mass carries out outer circulation with the speed of 82ml/min in reaction process, and temperature of reaction is 20~30 ℃, 180 minutes reaction times.Through sampling analysis, drawing the isobutyric aldehyde transformation efficiency is 99.6%, and the isopropylformic acid selectivity is 94.5%.
The comparative example 8
Employing is with the same bubbling column reactor of embodiment 1.Add 150 gram isobutyric aldehydes, 0.15 gram isopropylformic acid manganese.To 0.3MPa, in 180 minutes, at the uniform velocity feed 68 gram oxygen with the nitrogen punching press.Reaction mass carries out outer circulation with the speed of 170ml/min in reaction process, and temperature of reaction is 60~70 ℃, 180 minutes reaction times.Through sampling analysis, drawing the isobutyric aldehyde transformation efficiency is 99.8%, and the isopropylformic acid selectivity is 78.3%.