A kind of method that cumene oxidation prepares cumene hydroperoxide
Technical field
The present invention relates to a kind of by isopropylbenzene liquid phase oxidation into the method for cumene hydroperoxide, in particular to a kind of control
The method of by-product in preparing isopropylbenzene hydroperoxides production process
Background technique
Cumene hydroperoxide can be by being prepared with oxygen-containing gas such as air oxidation in liquid phase isopropylbenzene.Such oxygen
Change method is well known in the art.
In the reaction of such cumene oxidation, dimethyl benzyl alcohol (DMBA) and acetophenone (PMK) are formed as secondary
Product.The oxidation of subsequent propylene and the cumene hydroperoxide leads to propylene oxide (PO) and dimethyl benzyl alcohol (DMBA)
It generates.Dimethyl benzyl alcohol, which can be again converted to isopropylbenzene as the feedstock circulation of oxidation reaction with hydrogen generation hydrogenolysis, to be made
With.
In such method, the generation of propylene oxide co-production product is avoided, the biggish epoxy third of market value is only generated
Alkane product.
The method of the generation propylene oxide (PO) is commonly referred to as CHP/PO method.Usual CHP/PO method include with
Lower step: 1. isopropylbenzene and air catalytic oxidation generate cumene hydroperoxide (CHP);2. propylene is oxidized to epoxy by CHP
Propane, and itself is reduced to dimethyl benzyl alcohol;3. hydrogenolysis, which occurs, for the pure and mild hydrogen of dimethylbenzyl generates isopropylbenzene.
The step 1. in, due to cumene oxidation generate CHP while, CHP can further occurrence connect side reaction,
CHP is caused selectively to reduce, therefore, isopropylbenzene conversion per pass is generally below 30wt% in industrial process.
Therefore, to keep the concentration of cumene hydroperoxide in the reactive mixture relatively low.In those skilled in the art
In member, wish to realize higher oxidation rate when running under the above maximum cumene hydroperoxide concentration always.China
Patent CN201210429266.9 discloses a kind of method of high isopropylbenzene conversion ratio, uses non-metal solid C catalyst, ring
Border is friendly, cheap, but cumene hydroperoxide selectivity is not high.
While in existing technology and scheme, the method that specificity inhibits a certain by-product, e.g., suppression are not mentioned
Side-products methyl phenyl ketone (PMK) processed.Consider from Atom economy, dimethyl benzyl alcohol (DMBA) can be returned by dehydration hydrogenation
It is back to original isopropylbenzene, and acetophenone is then converted into the bad by-product of economy.
Summary of the invention
The present invention provides a kind of method that cumene oxidation prepares cumene hydroperoxide.α-first is added into isopropylbenzene
Base styrene dimer can realize specific isopropylbenzene conversion ratio in shorter time section.By-product inhibition can be added simultaneously
The selectivity of less economical acetophenone is effectively reduced in agent while can dramatically speeding up cumene oxidation reaction speed.
In order to solve the above technical problems, the present invention the following technical schemes are provided:
A kind of method that cumene oxidation prepares cumene hydroperoxide, comprising the following steps: in α-methylstyrene
In the presence of dimer, cumene oxidation prepares cumene hydroperoxide.
In the method for the invention, the α-methylstyrene dimer is including but not limited to 2,4- diphenyl -4- methyl -
1- amylene, 2,4- diphenyl -4- methyl -2- amylene, 1,1,2- trimethyl -3- phenyl indan, cis- 1,3- dimethyl -1,3- two
One of benzcyclobutane or trans- 1,3- dimethyl -1,3- diphenyl cyclobutane are a variety of.
In method of the present invention, the content of α-methylstyrene dimer should make α-first in reaction mixture
The amount of base styrene dimer is promoting amount.More specifically, the amount should preferably be such that be added without α-methylstyrene
The case where dimer, is compared to the specific isopropylbenzene conversion ratio of realization in shorter time section.
In method of the present invention, the concentration of α-methylstyrene dimer is 0.001-1.0wt%, preferably 0.002-
0.5wt%, more preferable 0.003-0.3wt%, the total weight based on reaction liquid phase mixture.
As a preferred scheme, method of the present invention can also carry out in the presence of by-product suppressor,
The composition of the by-product suppressor include active component and carrier, the active component be VIIB or VIII group element, preferably
One of cobalt, manganese, iron are a variety of.The carrier is selected from the oxide or carbon of the element of the periodic table of elements IIA, IIIA, IVA race
One of hydrochlorate is a variety of, preferably one of aluminium oxide, silica, magnesia or a variety of.
The content of activity component metal element is by-product suppressor total weight in by-product suppressor of the present invention
0.01~50%, carrier amount is 50%~99.99%.
A kind of preparation method of by-product suppressor of the present invention, comprising the following steps: (1) carrier is added to work
Property component metals element concentration be 1-40wt% aqueous metal salt in, stir 0.5-24h at 25-100 DEG C;(2) will
Concentration is the precipitant solution of 1-40wt%, is added in the mixture that step (1) obtains, stirs 0.5- at 25-100 DEG C
50h;(3) mixture for obtaining step (2) filters, and filter cake is dried under the conditions of 25-180 DEG C, then in 300-700 DEG C of hydrogen
1-20h is restored under gas atmosphere to get by-product suppressor is arrived.
The metal salt of the active component of by-product suppressor of the present invention is selected from nitrate, sulfate, chlorate or vinegar
One of hydrochlorate is a variety of.
Precipitating reagent in the preparation method of by-product suppressor of the present invention is selected from sodium hydroxide, potassium hydroxide, carbonic acid
Sodium, ammonium carbonate, ammonium hydroxide and urea are any one or more of;The molar ratio 0.5-5:1 of the precipitating reagent and metal salt.
By-product suppressor of the present invention is 0.0001~0.05:1 with the weight ratio for reacting liquid phase mixture, preferably
0.006~0.012:1.
In method of the present invention, the oxidant that oxidation reaction uses is oxygen-containing gas.
In method of the present invention, by cumene oxidation be cumene hydroperoxide 20-200 DEG C at a temperature of into
Row, suitably 50-150 DEG C at a temperature of carry out, more appropriately 60-120 DEG C at a temperature of carry out.
In method of the present invention, the pressure of oxidation reaction is not important, and can be chosen so as to best fit
Answer particular situation.In general, reaction pressure is from normal pressure to 1MPaG, preferably 0.05-0.5MPaG.
In method of the present invention, via the gas of one or more of gas vents removal of the oxidation reactor
Body may contain a certain amount of isopropyl benzene vapour.If desired, the isopropyl benzene vapour can be condensed into liquid and recycled.
The oxidation is carried out by being fed in reaction mixture using oxygen-containing gas as gas access material.Gas into
Oxygen concentration in material can be 5-100vol%, suitably 10-60vol%, be more appropriately 20-50vol%, wherein remaining
Excess is preferably inert gas, such as nitrogen.The average air containing 21vol% oxygen is preferred oxygen-containing gas charging.In
The temperature of the gas can be environment temperature to 200 DEG C at gas access.
The separate mode of by-product suppressor and reaction solution can choose the separation of solid and liquid of the routine such as filtering, centrifugation, absorption
Mode, the mode particularly preferably filtered are separated.
α-methylstyrene dimer can be separated with reaction solution by the common technique such as rectifying, extraction, preferably
It is separated using the technique of rectifying.
The effect of α-methylstyrene dimer of the present invention on the one hand can with radical reaction, then to isopropylbenzene
Transfer, and then improve the yield of isopropyl benzene hydroperoxide;Another aspect isopropyl benzene hydroperoxide, which decomposes, generates α-methylstyrene
For balanced reaction, dimer reversible reaction, which is decomposed, generates α-methylstyrene, inhibits balanced reaction to a certain extent to the right
It is mobile.
After α-methylstyrene dimer and by-product suppressor is added simultaneously, thus it is speculated that may be in by-product suppressor
Active component form similar complex pattern with α-methylstyrene dimer and isopropyl benzene hydroperoxide, enhance isopropyl
The stability of benzene hydrogen peroxide plays the role of that isopropyl benzene hydroperoxide is inhibited to decompose, and final realize turns in increase isopropylbenzene
The selectivity of acetophenone is effectively reduced while rate.
By this technique, during the use of cumene oxidation being cumene hydroperoxide, by controlling Alpha-Methyl benzene
The content of ethylene dimerization body, while the inhibitor containing metallic element is added, cumene oxidation reaction speed can be dramatically speeded up
While less economical acetophenone composition is effectively reduced, technique Atom economy is good, and by-product is few.
Specific embodiment
Analysis method:
For dimethyl benzyl alcohol (DMBA) and acetophenone (PMK), measured by gas chromatography.
Analytical conditions for gas chromatography are as follows:
Analysis instrument: GC1690 gas chromatograph;
Data record and processing: FL9500 chromatographic work station;
Chromatographic column: polarity capillary column in SE-54,30m;
Internal standard compound: mesitylene;Sample solvent: methanol
Column temperature: 120 DEG C;Gasification temperature: 220 DEG C
Detector: hydrogen flame ionization detector (FID), 220 DEG C
Sample volume: 0.2 μ L;Carrier gas: high pure nitrogen, 80ml/min
Split ratio: 60:1;Analyze duration: 8min
It for cumene hydroperoxide (CHP), is measured by indirect iodometric processes, accurately weighs certain sample in conical flask
In, isometric glacial acetic acid and saturated solution of potassium iodide is added, heating stirring 5min at 60 DEG C is then molten with sodium thiosulfate standard
Liquid be titrated to it is faint yellow, be added starch indicator 2 drip, continue to be titrated to blue disappearance, as terminal.By same steps, to not
The solution of sample-adding product does blank assay.
Method of the invention is described in more detail by following nonlimiting examples.
By-product suppressor 1 synthesizes:
The preparation of Co-MgO by-product suppressor: 20g cobalt acetate is dissolved in 180mL distilled water, is configured to 10wt%'s
Cobalt acetate aqueous solution.Then 27g magnesium oxide powder is added in above-mentioned cobalt acetate aqueous solution under 25 DEG C of stirring conditions, stirring
18h.The sodium hydroxide solution that mass concentration is 20wt% is prepared, 25mL is taken to be added in said mixture, and is aged at 85 DEG C
20h is filtered, washed, dries at 110 DEG C.8h is restored in 500 DEG C of hydrogen, the inhibition of cobalt supported magnesium oxide by-product can be obtained
Agent.
By-product suppressor 2 synthesizes:
The preparation of Ni- alumina byproduct inhibitor: 20g nickel acetate is dissolved in 180mL deionized water, is configured to
The nickel acetate aqueous solution of 10wt%.Then above-mentioned nickel acetate aqueous solution is added in 27g silicon oxide powder under 25 DEG C of stirring conditions
In, stir 18h.The ammonia spirit that mass concentration is 20wt% is prepared, 27mL is added in said mixture, and old at 85 DEG C
Change 20h, is filtered, washed, is dried at 110 DEG C.8h is restored in 500 DEG C of hydrogen, the suppression of nickel load alumina byproduct can be obtained
Preparation.
By-product suppressor 3 synthesizes:
The preparation of Fe-Mn- silica by-product suppressor: 14.8g ferric nitrate and 10.2g manganese nitrate are dissolved in 225mL
In ionized water, it is configured to the saline solution of 10wt%.Then above-mentioned water is added in 27g silicon oxide powder under 25 DEG C of stirring conditions
In solution, 18h is stirred.The ammonia spirit that mass concentration is 20wt% is prepared, 30mL is added in said mixture, and 85
DEG C ageing 20h, be filtered, washed, dried at 110 DEG C.8h is restored in 500 DEG C of hydrogen, ferrimanganic composite oxygen SiClx pair can be obtained
Product inhibitors.
Comparative example 1
1kg isopropylbenzene is placed in 2L titanium reaction kettle, which enters equipped with blender, the gas in bottom
Reaction kettle is boosted to 4barg in conjunction with reflux condenser, with nitrogen by mouth and the gas vent at top, the gas vent,
And reaction solution is heated to 105 DEG C.Air is passed through in reaction kettle once reaching the temperature, while being stirred strongly, and
Keep fluid temperature in reaction kettle constant at 105 DEG C.Wherein air is continuous feed, and isopropylbenzene is disposably to be previously added reaction
In kettle.
Reflux temperature in reflux condenser is maintained at 25 DEG C, to be condensed back the organic matter of entrainment.Adjust air feed
Amount, so that the oxygen concentration that oxygen concentration analyzer measures is maintained at 5vol%.
Different time points during the reaction take out the sample of reaction mixture.Measure each component in reaction mixture
Concentration (is indicated) by the wt% based on total reaction mixture.Wherein 0min indicates that reaction starts timing, and takes first sample.
Comparative example 2
9g by-product suppressor 3 and 1kg isopropylbenzene are added in reaction kettle, remaining condition is the same as comparative example 1.
Embodiment 1
1g 2,4- diphenyl -4- methyl -2- amylene, 7g by-product suppressor 1 and 1kg isopropylbenzene are added to reaction kettle
In, remaining condition is the same as comparative example 1.
Embodiment 2
5g 1,1,2- trimethyl -3- phenyl indan, 8g by-product suppressor 2 and 1kg isopropylbenzene are added to reaction kettle
In, remaining condition is the same as comparative example 1.
Embodiment 3
The cis- 1,3- dimethyl -1,3- diphenyl cyclobutane of 0.02g, 9g by-product suppressor 3 and 1kg isopropylbenzene are added
Into reaction kettle, remaining condition is the same as comparative example 1.
Embodiment 4
By 0.2g 2,4- diphenyl -4-methyl-1-pentene and 1kg isopropylbenzene are added in reaction kettle, remaining condition is the same as right
Ratio 1.
Experimental result
The corresponding selective calculated result of the experiment sampling analysis result and each component of the above comparative example and embodiment is converged
Always in table 1.
In comparative example 2, by-product suppressor is only added without adding reaction result when α-methylstyrene dimer
There is no significant change with the result of comparative example 1, when showing only to add by-product suppressor, does not have to generate shadow substantially to oxidation reaction
It rings.
It, can when adding a small amount of α-methylstyrene dimer and by-product suppressor simultaneously in Examples 1 to 3
To lead to CHP yield in the significant higher same time while effectively inhibit the production quantity of PMK.
In example 4, when only adding a small amount of α-methylstyrene dimer without adding inhibitor, can cause to show
The CHP yield in the higher same time is write, the production quantity of PMK also increases.
The above experiment shows to shorten by the α-methylstyrene dimer for only feeding relatively small amount and reach specific CHP
The time of concentration, the shortening (i.e. higher reaction rate) in this reaction time are very advantageously, because this will advantageously lead
Cause isopropylbenzene meter higher yield of the CHP relative to charging after certain period of time.
In addition, the experimental result is shown, by feeding α-methylstyrene dimer and by-product suppressor simultaneously, with
Dramatically increasing for CHP production quantity, the production quantity of PMK but increase seldom, meanwhile, DMBA can be advantageously converted into isopropyl
Benzene can effectively realize recycling.Such production procedure can occur for producing propylene oxide such as CHP/PO
In method.
1 comparative example of table and embodiment reaction result comparative situation