JPS5810538A - Manufacture of carboxylic acid ester from acylium anion produced by carbonylation - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Sils, especially carbon monoxide, anhydrous hydrogen fluoride, anhydrous hydrogen chloride and orenes having 7 or more double bonds. The present invention relates to the production of carbic acid esters by esterifying acyl fluorides and/or acyl chlorides produced from esters or esters.

Prior art such as British Patent No. 9112.31.7
Compounds with 7 or more double bonds are called esters? Emphasis is placed on an aqueous acid catalytic system for the production of carbic acid by further hydrolyzing the reaction product with excess water to produce carbic acid (and subsequently esterifying the carbic acid). are doing. In these methods, the aqueous acid medium is corrosive and expensive equipment is required. These prior art problems are solved with the carbic acid ester production method described herein.

Calanoic acid ester (e.g. methyl isobutyrate) with an acylium anion product (e.g. isobutyryl fluoride);
The alcohol theesterification in an amount less than the total amount required to react with all of the acylium anion product produces the carboxylic acid ester and anhydrous acid (e.g., hydrogen fluoride or hydrogen chloride). Generated by playing. The acyllium anion product is produced in any reaction, but preferably with carbon monoxide and an anhydrous acid (e.g., hydrogen fluoride) as described herein, which is capable of reacting with carbon monoxide and an acid anhydride. It is produced by reaction with an organic compound (eg, propylene) under conditions that produce an acylium anion product (eg, isobutyryl fluoride).

In another embodiment of the invention, a portion or all of the carbic acid ester (e.g., methyl isobutyrate) is separated from the esterification mixture, and a portion or all of the carbic acid ester is separated. The remainder of the subsequent esterification mixture (e.g., hydrogen fluoride, unreacted isobutyryl fluoride, unseparated methyl isobutyrate) is reacted with an organic compound (e.g., propylene) to further produce an acylium anion product (e.g., isobutyryl fluoride). recirculated to produce . In another embodiment of the invention, separation and esterification are performed simultaneously so that side reactions are substantially minimized. The acylium anion product is esterified while the acid anhydride is separated and recovered. A lower alkyl deropionate or isobutyrate (eg, methyl isobutyrate) can be oxydehydrogenated to form a lower alkyl acrylate to a methacrylate (eg, methyl methacrylate).

Produce calcaric acid ester from the acylium anion product. Newly discovered production blades for the production of acylium anions (m<fluoride"df*t:i chloride), such as isobutyryl fluoride, especially with carbon monoxide and the acids described herein. The acyllium anion product produced by the reaction with an organic compound is less than the total amount required to esterify all of the acylium anion product in the mixture to a carbic acid ester (e.g., methyl isobutyrate). esterification with an amount of alcohol, this reaction being carried out under conditions to produce the caldic acid ester and regenerate the acid as described herein.

In another embodiment of the present invention, the method of the present invention includes the step of separating /~10ocs' of acid from the esterification mixture, and further comprising ~100 oocs' of the separated acid; It also includes the step or steps of recycling to react with the organic compounds described herein to form a mixture comprising an acylium anion product and an acid anhydride.

In another embodiment of the present invention, the method of the present invention comprises the step of preparing a carboxylic acid ester from an esterification mixture.
In the step of separating the acylium anion product, the esterification product mixture l~/θθ4f remaining after separation of the caldic acid ester is further reacted with -carbon oxide and an organic compound as described herein to form the acylium anion product. recirculating to produce a mixture comprising:

In another embodiment, the CalIy'fII esters produced by the process of the invention, particularly lower alkyl propionic acids such as methyl propionate and methyl isobutyrate, and (7?#-j) isobutyric acids. The esters are suitable for direct oxydehydrogenation to lower alkyl unsaturated esters such as methyl acrylate and methyl methacrylate by known methods.

An acylium anion product (e.g., isobutyryl fluoride) as described herein, such as imbutyryl chloride or imbutyryl bromide, is reacted with hydrogen fluoride to produce isobutyryl fluoride in any manner, and hydrogen chloride or ? It can be produced by regenerating hydrogen habromide.

However, a more preferred method b is a method by carbonylation reaction of -carbon oxide, an acid anhydride as described herein, and an organic compound as described herein. A preferred cal/nylation reaction to produce the acylium anion product is described below.

a reactant for producing an acyllium anion product;
The reactants may be from any source, but must be free of harmful substances that would interfere with the process of the present invention. It is preferred that the reaction system be anhydrous, which must be less than 0.001% by weight, to prevent side reactions that would produce undesirable ethers.

- The carbon oxide may be from any carbon monoxide source, but is preferably substantially anhydrous to maintain substantially anhydrous reaction conditions. - The carbon oxide may be diluted with other substances that do not interfere with the reaction. For example, dry synthesis gas deposited fCI/'i coal combustion gas can be used. Preferably, dry carbon oxide itself is used.

Organic compounds are those capable of reacting with carbon oxides and acid anhydrides, i.e. capable of being carbonylated to produce acylium anions, such as organic esters or carbonylated compounds as described herein. An olefin having at least seven double bonds capable of producing the acylium anion products described herein.

Cal is represented by the general formula of Queen's organic ester for the nylation reaction, 1 R-C-0-R' In the above general formula, R, such as methyl, ethyl, propyl, dodecyl, eicosanyl, 20 alkyl having up to 5 carbon atoms. Alkyl is preferably methyl or ethyl; fr is propyl or isozorobyl, with ethyl and isozorobyl being preferred. R' is alkyl having 2 to 20 carbon atoms, such as ethyl, propyl, t-butyl, dodecyl, eicosanyl. R/t, x, preferably ethylene, and isopropyl is most preferred.

When using organic esters in the carbonylation methods described herein, any of the esters listed in Kanmei A calyx may be used. However, isopropyl isobutyrate (2-propanol-co-methylpropionate) and ethyl isobutyrate (ethanol-ni-methylzoropionate)
It is preferable to use isopropyl imbutyrate (2-pronognol propionate) or ethyl propionate (ethanol zolopionate), and it is particularly preferable to use isopropyl imbutyrate or ethyl propionate.

ζ having at least a double bond capable of forming an acyllium anion product (carbnylated to become an acyllium anion product) and used in the method V of the present invention
Examples of organic compounds that can be
It is an olefin with carbon atoms at 0 m't. The olefin Fi, alkyl or fr may be substituted with aryl or cycloalkyl or other substituents that do not interfere with the process of the invention. Furthermore, the olefin is /, 3
- Like butadiene, it is possible to have multiple bivalent bonds in the entire molecule that do not interfere with the method of the invention.

Preferred olefins are ethylene, 7'opyrene, isobutyne, 1-butene, 2-butene, 1,3-butadiene, with ethylene and propylene highly preferred.

Although all of the organic compounds described herein may be used in the method of the present invention, propylene is particularly preferred6. Must be water-free, i.e. anhydrous. As used herein, the term "anhydrous" means substantially free of water, e.g.
An acid that is less than ppm or, if water is present, means an acid that does not interfere with the production reaction of asyllium anion or caldenate ester from asyllium anion.

The anhydrous acid that can be used in the method of the present invention is hydrogen fluoride (
hydrofluoric acid) (HF) and hydrogen chloride (hydrochloric acid) (HC
t). The most preferred acid anhydride for the process of the invention is hydrogen fluoride (hydrofluoric acid).

The alcohol used in the esterification method of the present invention can be a primary alcohol or a secondary alcohol that does not decompose under the esterification and separation conditions and does not react with the regenerated acid to form anhydrous #. Examples of alcohols #-j are alkanols having up to 2θ carbon atoms. Preferred alkanols are those having up to 5 carbon atoms. Alcohols suitable for Ogome are mep/-k, ethanol, and 10-nonol.
The most preferred alcohol is methanol.

- The reaction of carbon oxide with the organic compound described herein and the acid anhydride described herein can occur at a temperature between θ°C and lOθ0C, with the upper temperature limit determined by the formation of by-products. For reactions between the preferred reactants described herein, the temperature can be from lIO<0>C to gO<0>C;
Preferably it is about 40°C. -Carbon oxide pressure pearl (/IA, 7 psia) about 90g pearl (
6θθθpsia) f 7? ? 164gθ pearl (/
Although it can range up to θt 000 psla), it is generally
O pearl (5,0OQpsta), preferably 1
02 Pearl (/, S 00 psia) ~201
A pearl (3*000 psla), and the pressure is
It is increased as necessary due to the solubility of carbon monoxide in the anhydrous acid and to increase reactor productivity.

The molar ratio of hot hydroxyl to the organic compound described herein is /:/-
Must be 100:/, but typically 10:/-2
0:/, preferably about is:/. - molar ratio of carbon oxide to organic compound described herein:
lmafa more than that, but preferably/, 5:/~l
:/ corresponds best to the saturation limit of carbon monoxide in the reaction mixture during and at the end of the reaction.

All of the carbon monoxide and anhydrous acid (e.g., anhydrous hydrogen fluoride) to be reacted with the organic compound must be thoroughly mixed before contacting with the organic compound (e.g., propylene) described herein.

Next, the organic compound is reacted while being mixed with the premixed carbon monoxide and acid. Generally, the reaction occurs within a few minutes, depending on pressure and temperature, to produce an acylium anion product (eg, imbutyryl fluoride). The organic compound itself can be diluted with carbon oxide or an inert diluent (eg methane, ethane, propane) before reacting with the acid anhydride.

Although the reaction can be carried out in a semi-batch reactor, a plug flow reactor, a reverse mixer reactor (C3TR) or other reactors known to those skilled in the art, the preferred reactor is a plug flow reactor. It is.

, the esterification reaction of an acylium anion product (e.g. isobutyryl fluoride) with an alcohol, especially methanol, is carried out at a temperature of 20° C. to /50”C and /Parr (
/4t,? psia) ~ 34'θ pearl (5e 00
(7 psla), but usually
Temperatures from 110°C to '70'C and 3,3 pearls (5
0 psia) ~A, 7 barj' (/00 p
occurs at a pressure of sia). Temperature and pressure are determined to avoid decomposition of the desired product and to facilitate product separation.

It is preferred to stir the reactants during esterification. In many cases, when rapid mixing is used, the esterification reaction can be completed within seconds to minutes with simultaneous regeneration of the acid anhydride (eg HF).

A critical feature of the esterification reaction is that the molar ratio of alcohol (e.g. methanol) to acylium ionic product is
:/ It is to have miscellaneous things in f#i.

That is, the total amount of alcohol that reacts with the mixture containing the asyllium anion product, and all of the asyllium anion product forming a sulfuric acid ester? 16 (
Must be less than the required amount of n7 alcohol.

Although it is possible to inject the entire amount of alcohol into the mixture containing the asyllium anion product, preferably the alcohol is added in partial amounts into the mixture containing the asyllium anion product. Since the esterification step is an exothermic step, cooling may be required. 1- for the mixture
It contains carbon oxide, unreacted organic compounds, acid anhydride, and carboxylic acid ester. Preferably, the mixture contains gaseous hydric acid, and the H% is preferred when the acylium anion product is isobutyryl fluoride. When esterifying acylium anion products such as isobutyryl fluoride,
The ratio of the amounts of anhydrous tR (for example, hydrogen fluoride) and isobutyryl fluoride is anhydrous fluoride [(AHF)O0θ/~? 5.3 parts by weight of external a and isobutyryl (l BF l 99.0q
-4.5 cars, but preferably rtAHFl
o, 0 to 90.0 parts by weight vs. IBF? θ~10 weight is in parts. The amount of anhydrous (e.g. hydrogen fluoride) in the mixture is determined by the effective operation of the process as well as between the acylium anion products (e.g. isobutyryl fluoride) and hydrogen fluoride and carbon monoxide and alkyl isobutyrates such as methyl isobutyrate. depending on the ease of separation of the acid anhydride (e.g. fluoride) from the product mixture containing the various components.

After completion of the esterification reaction (J depends on the reaction product,
The produced carpeptate ester (7)/~70θ is separated from the product mixture of the esterification reaction.

Preferably, the carboxylic acid ester (DgO-100) is separated and the remaining esterified product mixture is recycled for further reaction with the reactant to form the acylium anion product. Cycle #' may include -carbon oxide and/or acid anhydride and (also ri) unreacted organic compound and (also ri) unesterified acylium anion product.

In another embodiment of this invention, the acid anhydride/
˜lθ0° (preferably gθ˜100°) is separated from the esterification product mixture and recycled for further reaction to produce the acylium anion product. This recycle may contain unseparated, unesterified asyllium anion products and unreacted organic compounds (also rtl calcium esters).

Separation can be carried out by any of the known separation methods such as distillation or solvent extraction. Preferably, < uses distillation.

A preferred embodiment for the production of the cal-7-acid esters described herein comprises the esterification of the Nl acylium anion products described herein under substantially anhydrous conditions with the alcohols described herein. The method of the present invention comprises separating the caldenate ester, unreacted alcohol, acid anhydride, and unreacted acylium anion product under conditions in which the esterification continues until substantial completion of the esterification. gO ~ 100 inches (preferably t
It can also be enriched by separating the aqo~100%) and esterifying the separated anhydride with recycling to further produce the acyl anion product.

The process μ of the invention, preferably from a Nistil feed mixture,
separating qO% to 100% of the carbonaceous ester and 30 to 700% of the acid anhydride and esterifying the separated acid anhydride with recycling to further produce an acylium anion product. I can do it.

Preferably, under conditions where the esterification of the asyllium anion product continues to substantial completion, i.e., the gO content of the asyllium anion product is ~100%.

Separation occurs during esterification by distilling the esterification reaction mixture under conditions where preferably rxqo ~100% is esterified to the carboxylic acid ester.

The distillation conditions are such that the formation of coal products is substantially reduced. The distillation conditions rt are also modified to substantially reduce the formation of halodanated by-products, especially H
It is also a condition that eliminates F. Preferably, the esterification yield is from 90% to 100% in actual terms.
100% is highly preferred.

A schematic diagram of a preferred esterification and separation apparatus is shown in the accompanying drawings. This apparatus, which is adaptable to the esterification method of the present invention, is useful in bamboo for esterifying imbutyryl fluoride with methanol to methyl isobutyrate. Asylium anion product (e.g. izuprityl fluoride source) 20
Metering in f32 via line 30, line 34, valve 36, line 38 to esterification reactor 40
where it is reacted with an alcohol (e.g. methanol). Alcohol is passed from the alcohol supply source 42 through a pump F44 to a line 46, a valve 48, and a line 50.
It is supplied to the esterification reactor 40 through the steps. Feeds of acyllium anion product (e.g., isobutyryl fluoride) and alcohol (e.g., methanol) are supplied to dispersion nozzles (disp) connected to lines 38 and 50, respectively.
(not shown) into the esterification reactor 40, which may be fitted with baffles or other means for ensuring rapid mixing of the reactor. can. The reaction mixture from esterification reaction #40 is passed through line 541 to distillation column 52 via a reflux entry.
It is entered at a point 56 (above point 60) which is between the yJ point 58 and the liquid phase removal point 60. ), unreacted alcohol (eg, methanol), and regenerated acid (eg, hydrogen fluoride), and to complete the esterification reaction initiated in the esterification reactor 40 in the distillation column 52.

The attached drawing shows the supply and discharge points.
This distillation column 52μ, which is shown with oint), is applicable to the esterification of isobutyryl fluoride with substantially anhydrous methanol. However, as known to those skilled in the art, the feed and discharge points can be easily modified to accommodate anhydrous esterification with other alcohols. For example, if the boiling point of the ester is lower than the boiling point of the acid anhydride, the ester will be discharged at the top and the anhydride will be discharged at the bottom.

Unreacted alcohol (methanol) and/or acylium anion addition products (e.g. imbutyryl fluoride)
and (hydrogen fluoride and/or) Nisdel (e.g. methyl isobutyrate) is discharged from a discharge point 60 and passed through line 62 into a heat exchanger 64;
It is then cooled if necessary and passed via line 66 1...' into the metering port/producer 8 and via line 70 2 into the esterification reactor 40. The acylium anion product (e.g., isobutyryl fluoride) reacts and combines with the alcohol (e.g., methanol) during the stripping operation that occurs between the feed point 56 and the liquid stream outlet point 60, resulting in the formation of an ester. (e.g. methyl isobutyrate), the ester descends through the stripping section and is discharged from the output nozzle 2 of the distillation column 52 and sent through the lie/74 into the storage 76. A slip of the crude product (5 lip l) passing through the lye/74 can be reintroduced into the distillation column 52 from 84 through the heat exchanger 80t- and line 82 from the two-ear 78. The acid (e.g., hydrogen fluoride) rises through the distillation column 52, exits at an overhead outlet 86, and passes through line 88 into a heat exchanger 90 where it is partially and completely condensed. ,
It is sent through line 92 into separation column 94 . Shun Muzu (
Hydrogen fluoride, for example, is passed through LY/96 into a storage unit 98 or 102 for reuse to produce further acyllium anion product.

Separated column bottoms (5eparator boticrns)
) rt from the bottom of the separation column through line 96, all or a portion of which is sent back through line 98 from point 58 to the distillation column to the reflux. Condenser and separation column operations may be specified by those skilled in the art to facilitate the removal of impurities and/or byproducts that are either more or less volatile than hydrogen fluoride (HF). can do.

In another embodiment of the invention, line 104
A second solvent is added as a stripping agent to enhance the removal of acylium anion addition products (e.g., isobutyryl fluoride) from esters (e.g., methyl isobutyrate), thereby removing heat exchanger 64 and removing heat from the heat exchanger 64. Exchanger 90
The entire energy load can be applied to

In another embodiment of the invention, heat exchange @%6
In another embodiment of the present invention, the level at point 60 can be chosen to remove the alcohol (e.g. 1vIs is added co-currently with the alcohol into the reactor 40 to aid dilution and mixing of the ester (methanol) and enhance the stripping of the regenerated anhydride (e.g. HF). -ji10
Remove through 2. The solvent used should be inert towards the reactants under the reaction and separation conditions and should be compatible with the ester (
does not azeotrope with anhydrous acids (e.g. methyl inbutyrate) or anhydrides (hydrogen fluoride) and has a boiling point intermediate between acid anhydrides (e.g. HF) and esters (e.g. methyl isobutyrate), enhancing separation. The solvent preferably has a low heat of vaporization. Solvents useful for the esterification and separation of imbutyryl nonafluoride esterified with methanol are hydrofluoroalkanes having up to -0 carbon atoms, but preferably carbon atoms ft in the ris box.
is a hydrofluoroalkalka/.

The present invention will be explained below with reference to Examples.

Under adiabatic conditions, the esterification of isobutyryl fluoride based on an amount of methanol less than that required to esterify all of the isobutyryl fluoride to methyl isobutyrate was studied using the method described below.

Methanol introduction device C311 Pearl (500 psla)
a thermocouple connected to a continuous temperature recorder, an air motor, and a 1.00 Orpm VC-regulated stirrer.
oy CParr) 1 metered amount of tidal reactor in the reactor,
Anhydrous hydrogen fluoride (if used) and isobutyryl fluoride were charged (maintained at dry ice-acetone temperature). After charging, the reactants and reaction vessel were brought to a predetermined temperature of 1 jVc, and the temperature recording needle was started.

One metered amount of methanol (less than the amount required for reaction with all of the isobutyryl fluoride) is then injected into the reactor. The initial temperature of methanol was room temperature. After completion of esterification, the mixture was subjected to gas chromatography (G, C,
) and analyze it with friends. From the temperature-time records, an increase in temperature was observed. Generally, the first temperature increase is due to the heat of mixing, and the first temperature increase is due to the esterification reaction.

Implementation f'lJ/2ruC's inbutyryl fluoride, IBF (Q/'?, 321
da, 66 mol), iai, 2t methanol (co/℃
) was esterified by injection. Reaction mixture temperature [rt
,, after initially falling, A4 for the next 3.2g minutes.
', ACK has been raised The reaction is complete, G, C, analysis results show that it is anhydrous hydrogen fluoride (/zakof%Q, /%k) and I/l! i#me? Only 8(4(/za, λ1S, 1 mole) is produced, Sθ, 3f[),! It was found that the inbutyryl fluoride (rA mol) was unreacted.

Example 9.3C anhydrous hydrogen fluoride 6. Af (10 weight) and isobutyryl fluoride '122.1. The mixture with f (deOM quantity 2) was esterified with -/C methanol 133f (methanol was added once). After an increase in temperature of 20.7'C was observed, the following , 3K, warm iris for 4 seconds
The temperature rose to /Koz℃. The reaction was complete, and G, C, analysis results showed that methyl isobutyrate (Da/A, Of>, anhydrous HF (
/311.3f), unreacted isobutyryl fluoride (5/,
gf).

Example 3 A mixture of anhydrous Japanese aqueduct S Da O, Da 2 and isobutyryl fluoride &9.9F at 30°C was mixed with 1 g of methanol (<22°C)
, Aft 1 time VC addition and esterification ratio. Under these conditions, /,! After i seconds, the temperature continuously increases to 3
The temperature rose from 0°C to daq, sc. The reaction was complete, and analysis revealed that 2f methyl imbutyrate had been produced. The amount of anhydrous HF was SS, 7 g, and the amount of unreacted isotutyryl fluoride rjg.

Example: To produce methyl isobutyrate by the method of Hakumei Damoto,
below)! ! You can use the following method.

A plug-flow reactor is used for the production of isobutyric acid from f-ronobutylene. Plug flow reaction I! F has a pre-mixing section of about 3 m (S ft), and comes with an inner diameter of about 1/2 m, 7 inches (about 1 - m (da O feet)) pipe.
Approximately 1. It is equipped with injection points and heaters spaced tFFI (!f feet) apart.

Cal-nylation reaction is carried out at 50℃ and approximately 190 par(J*
g () () psla), i, o:iu”, i,
The process is carried out at a molar ratio of propane, anhydrous hydrogen fluoride, -saponified carbon of 3, and a flow rate of about 1, s ~/h (3, 7 h).

injecting anhydrous hydrogen fluoride and carbon monoxide into the premixing section;
Then, the two were thoroughly mixed, and about 90% of fronon was added to the mixture of anhydrous hydrogen fluoride and carbon monoxide. , 2! ;
m (!f ft) intervals, with the final addition of pro/ben approximately q, ism<30 ft) from the beginning of the reactor).
It will be held at After the reaction is completed, about lθ, 6ri! ;m C3S
ft) At the injection point, methanol is injected into the reactor, preferably as quickly as esterification occurs and methyl isobutyrate is formed, allowing esterification to occur. The amount is smaller than that of isobutyryl fluoride produced in the methanol-injected leaves. This part of the reactor where the esterification occurs is exposed to about 100°C, 4000 psla, and 7000 psla. Methyl isobutyrate is separated from the final product mixture by simple distillation, and the remaining imbutyryl fluoride, carbon monoxide, and anhydrous hydrogen fluoride are injected into the premix section of the reactor. Recirculated with hydrogen fluoride.

In another embodiment of the continuous reaction, the acylium anion product (isobutyryl fluoride) is added to the esterification spindle.
The product mixture containing is sent to a separator where excess carbon monoxide and 10 to 90% of excess anhydrous hydrogen fluoride are removed and recycled, while preferably rsio parts by weight of anhydrous hydrogen fluoride and 90 parts by weight of imbutyryl fluoride! After the product mixture is esterified as described above, the remaining product mixture is recycled by separating the methyl inbutyryl fluoride and separating the unreacted isobutyryl fluoride and anhydrous hydrogen fluoride.

Made of methyl acrylate or methyl methacrylate! Acylium anion products (e.g. propionyl fluoride or isobutyryl fluoride) as described in Specification 11
After esterification, the methyl esters of carbine #t, such as /lopimanic acid or inobutyric acid, prepared from U.S. Pat. ; gj5', Koge No. 3, same t1N, 3
．． ! ;g! ;, 1lI No. 9, same W, 3. ! ;g3.2!
; No. 0, No. 3. b31I, No. 179, No. 3.6S
Ko, Ajq No. 3. b6o, siu, same number 3. q
bb, i'yi issue, same number 3.7g/, 336, round bacteria 3
．． 7g da, hiroza 3, same tiK3. g3;! ;, core 9
Month, same No. J*? /7mA? No. 3, No. 3.94Jr, No. 939, No. 3.74g, IQ9
No. 3.9'! ! ,”30/issue, 4th part, 02
9. l, No. 93, same No. DA, obi, bri No. 3, same No. 'J
-, OK'/, lIA! No. i, No. u, Qzag, 60-
Oxydehydrogenation can be carried out by the method described in J.D. and British Patent No. 1, Daqri, s9?4iF specification.

Preferably, the catalyst has the empirical formula % [In the above empirical formula, for Fa/atom, X is phosphorus O, Co!
f ~ 3.3 atoms, and 2 indicates the number of oxygen atoms (fr) required to satisfy the valence requirements of the catalyst] A catalyst containing iron, phosphorus, and oxygen that is electrically layered by K. be. A more preferred catalyst is U.S. Pat. No. 3.9, 9! ;q
Aya, Me, (Here Me
d, accelerator Ll, Na, Rb%Ce, Mg
%Ca%Sr%Br, and mixtures thereof, y
Indicates the number of promoter atoms for ri wheat atoms, 0.01
~2.0). The produced methyl acrylate or methacrylate is then
It is separated by methods known in the art, such as distillation or extraction in the presence of polymerization inhibitors.

Although the present invention has been described with specific details of several illustrative embodiments, the invention is not limited by such details except insofar as these details appear in the claims. There's no light because it's a book.

[Brief explanation of the drawing]

The accompanying drawings illustrate one embodiment of the esterification-separation method of the present invention. Explanation of drawing numbers 20... Acylium anion product (isobutyryl fluoride source), 40... Esterification reactor, 42... Alcohol supply source, 62... Distillation column, 64.90... Heat exchanger, 76... Storage device, 94... Separation column, 98.
109...Storage device.

Claims (1)

[Scope of Claims] (1) A mixture containing an asyllium anion product is esterified into a carboxylic acid ester under anhydrous conditions with less alcohol than is required to esterify all of the asyllium anions in the mixture. a group consisting of primary alcohols having up to 20 carbon atoms and primary alcohols having up to 2 carbon atoms; the acyllium anion product is reacted with - a carbon oxide and an anhydride selected from the group consisting of hydrogen fluoride (HF) and hydrogen chloride (HC/); - a carbon oxide and an anhydride; and that the organic compound is produced from a reaction with an organic compound having the ability to an ester having at least one double bond capable of forming an acylium anion and having up to 20 carbon atoms; It is selected from the group consisting of olefins having atoms, and the esterification is carried out at a temperature of 2°C to 2°C.
carried out in the presence of the acid anhydride and at a temperature range of 150° C. and a pressure of 1 psia to 3170 par (5,000 psia), and the anhydride to acylium anion product. The initial amount of acid anhydride t, θ/~
95.5 times the world's asyllium anion product qq, o
A method for producing a carboxylic acid ester from an acyllium anion product, characterized in that it comprises a range of q to q, 5 parts by weight. 121 The organic compound is an ester from the group consisting of isopropyl acid, ethyl isobutyrate, isopropyl propionate, and ethyl propionate. The compound has at least one double bond capable of forming an acyllium anion product, and 1.
111. Process according to claim 111, characterized in that the olefin has up to 20 carbon atoms r. 14; The method according to claim 111, characterized in that the olefin is ethylene. +51 Process according to claim il+, characterized in that the olefin is propylene. 16+ The method according to any one of claims 11 to 51, characterized in that the alcohol or methanol is alcohol or methanol. and recycling the separated acid anhydride to react with carbon oxide and an organic compound to produce further acyllium anion product. The process according to claim 6. 16. The method of claim 16, further comprising the step of recycling 1% to 100% of the acylium anion product to further produce the acylium anion product. A method according to claim 16+, characterized in that Q(l anhydrous hydrogen fluoride to acylium anion product (
The initial amount of acyl anion product (acyl fluoride) is 70 to 90 parts by weight of anhydrous hydrogen fluoride to 90 to 90 parts by weight of anhydrous hydrogen fluoride.
Claim No. 91 (method according to claim 91) that the anhydrous acid is hydrogen fluoride -41!F
Claim No. # (method according to claim 71) +13 The acid anhydride is hydrogen fluoride 1r- Claim No. 18+ The method according to IJ. The mixture contains hydrogen hydride and imbutyryl fluoride, the alcohol is methanol, the amount of methanol initially added is 70 to 9996 of the amount of isobutyryl fluoride, and the amount of anhydrous hydrogen fluoride in the mixture is , substantially within the range of 6 to 20 moles of anhydrous hydrogen fluoride per mole of isobutyryl fluoride (method according to claim 11). 3.3 pearls (50
9sla) ~j, , '7 par 7' (/ 00
Claim VI characterized in that the process is carried out within the pressure range of IIO''C to 70°C.
The method described in section Jg aa. 2. A process according to claim 1, characterized in that it comprises a distillation step for separating the produced isobutyrous #σ) gos ~100% from the riS esterification product mixture. Oe Process according to claim 1, characterized in that the distillation step and the esterification step occur simultaneously. Process according to claim Q61, characterized in that from 90 to 100 tlr of methyl isobutyrate are separated from the esterification product mixture. Particularly, under anhydrous conditions, the mixture containing the acyllium anion product is esterified into the corresponding ester selected from the group consisting of methyl propionate and methyl isobutyrate. esterification with a small amount of methanol, thereby forming a carboxylic acid ester and regenerating the acid from the anion; and separating the ester and converting it in the gas phase with the corresponding unsaturated carboxylic acid ester. A certain methyl acrylate
r is oxydehydrogenated to methyl methacrylate, and the acyl anion product is -carbon oxide, an olefin selected from the group consisting of ethylene and propylene, and hydrogen fluoride (HF) and hydrogen chloride (HCJ!). with an anhydride selected from the group consisting of: acylium anion product under conditions that produce an acylium anion product; A method for producing an unsaturated carbic acid ester selected from the group consisting of methyl acrylate and methyl methacrylate. 6g The method according to claim 1, characterized in that the acid anhydride is hydrogen fluoride. The method according to claim Q9, wherein the olefin is propylene. 1211 The oxydehydrogenation process is based on the empirical formula FePxO2
(In the above experimental formula, for Fe/atom, X ke P atoms means 0.2S to 3.5, which is the number of oxygen atoms required to satisfy the valence requirement of a 2-digit catalyst. 69. A method according to claim 69, characterized in that a catalyst comprising iron, phosphorus and oxygen is used, as defined in the following claims.