JPS58225038A - Manufacture of acetic acid - 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 The present invention relates to a process for producing acetic acid from methanol by calzenylation.

Acetic acid has long been known as an industrial chemical and is used in large quantities in the manufacture of a variety of products. −
A method for producing carboxylic acids by the reaction of carbon oxide and alcohol (calzenylation) is described in Example λ, published in U.S. Patent No. 2
, No. 729, 651.

No. 4,133,963 and No. 4,218,340. However, such prior art techniques involving cal-7p-nylation reactions require the use of very high pressures. Cal 71 effective with smaller pressure? Nilation methods have also been proposed. For example, French patent no.
No. 573,130, in the presence of compounds of Group I noble metals such as iridium, platinum, nozeradium, osmium and ruthenium, and in the presence of bromine or iodine, smaller than those described in the said U.S. patent. The calzenylation of methanol and mixtures of methanol and methyl acetate under pressure is described. U.S. Pat. No. 3,769,329' and U.S. Pat. No. 3,772,380 disclose a method for producing acetic acid from the same reaction using an iridium or rhodium component together with bromine or ethyl chloride. states. U.S. Patent Nos. 3,689,533 and 3,717,67
No. 0 discloses a gas phase process for producing acetic acid using various catalysts containing a carrier-Fvc dispersed rhodium component. However, the low pressure carbonylation method of et al. requires the use of expensive noble metals. More recently, Belgian Patent No. 860,557 describes a method for producing carboxylic acids by carbonylating alcohols using trivalent phosphorus compounds as promoters in the presence of tannickel catalysts and in the presence of iodides. is disclosed. This method allows low-pressure carbonylation without using noble metals. Although this method is effective, there is room for improvement in terms of yield of the desired acid.

One improved method is described in pending US patent application Ser. No. 219,786, filed December 24, 1980. Please write the specification of the application, molybdenum.
in the presence of a catalyst containing a nickel or tungsten-nickel cocatalyst component, in the presence of an iodide, and in the presence of a promoter containing an organophonic compound for organophosphorus compound extraction.
A method for producing acetic acid membranes by total carsenylation of methanol is disclosed.

It is an object of the present invention to provide another improved method for carrying out the carbonylation of methanol in the presence of a catalyst having the above-mentioned properties.

An important discovery in the present invention is that calcium 7j? is converted to methanolkaacetic acid. The rate of the nylation reaction is such that the ratio of the hydrogen partial pressure to the carbon monoxide partial pressure in the reaction zone is 005-04, preferably 015-0.30, more preferably 02-0.
A mixture of carbon monoxide and hydrogen maintained at 0.25 -
This means that the carbonylation can be significantly increased by carrying out the entire carbonylation using a compound. Therefore, in the method of the present invention, molybdenum-nickel i'
methanol with a mixture of carbon monoxide and hydrogen in an amount such that said ratio of hydrogen partial pressure to carbon monoxide partial pressure in the presence of a catalyst comprising a pygesten-nickel cocatalyst component is within said value range VC. Make it react.

The reaction is carried out subhypercaronally and generally at least 1.1
1 (15psi) and 141%・(2,0
It is preferred to use carbon monoxide partial pressures lower than 00 psi), most preferably Vi, 1.1 to 70 psi (
-carbon oxide partial pressure of 15 to 1.000 psi),
It is also possible to use carbon oxide partial pressures of 1 to 5,000 psl or even 10,000 psl. Of course, the total pressure is such as to give the desired ratio of 82 partial pressure to 00 partial pressure.

It is also preferably as required to maintain the Vi liquid phase. As is well known in carbonylation technology, as the 00 partial pressure increases, the reaction rate increases, and according to the findings here.

If, at any given 00 partial pressure, only a fraction of hydrogen is present such that the ratio of the hydrogen partial pressure to the 00 partial pressure has the above-mentioned value, the reaction rate increases by an unexpectedly large amount. Regarding the ratios mentioned above, the reaction rate is not significantly affected by either small or large ratios.

Although larger ranges of temperature i, such as from 25 to 350°C, can be used, it is preferred to use temperatures from 1 to 250°C, with more preferred temperatures generally from 125 to 22°C.
It is in the range of 5°C. Lower temperatures can be used but tend to reduce the reaction rate & higher temperatures can also be used but have no particular effect. Reaction time is not an important A parameter of the method of the invention.

Although highly dependent on the temperature used, typical residence times generally range from 0.1 to 20 hours.

The final reaction mixture produced usually contains volatile components such as hydrocarbyl iodide, unreacted alcohol, and the corresponding ester and/or ether along with the product acid. These volatile components can be recycled to the reaction after separation from the acid. After the desired residence time has elapsed, the reaction mixture is separated into several components, for example by distillation. Preferably one reaction product, e.g. one distillation zone, is effective to separate the volatile components from the product acid and to separate the product acid from the less volatile catalyst and promoter components of the reaction mixture. Lead to a fractionation tube or series of fractions U. The boiling points of the volatile components are sufficiently far apart that separation by distillation, which is conventionally used, presents no special problems. Similarly,.

The high boiling organic components can be easily distilled off from the metal catalyst components and any organic promoters, which may be in the form of relatively non-volatile complexes. The cocatalyst and promoter (including iodide components) recovered in this way are
Mix and react with fresh alcohol and carbon monoxide to form an additional amount of Cal73? can produce phosphoric acid.

Although not necessary, the process can be carried out in the presence of an organic solvent or diluent. Since methanol has a relatively low boiling point, the presence of a high boiling bath or diluent, preferably acetic acid, and the corresponding ester, such as methyl acetate, allows the use of lower total pressures. . Alternatively, the solvent or diluent can be any organic solvent that is inert under the environment of the process, e.g.
(e.g. octane, benzene, toluene, xylene and tetralin), or halogenated hydrocarbons (e.g. trichlorobenzene), or carboxyl esters (e.g. cellosolve acetate), etc. be able to. Mixtures of solvents can also be used, for example mixtures of methyl acetate and acetic acid. If an acid/acid is used, it is preferably acetic acid since the preferred solvent is system specific such as acetic acid and/or methyl acetate.

Non-inherent solvents or diluents should be selected to have boiling points sufficiently different from the components of the reaction mixture to permit easy separation, as will be apparent to those skilled in the art.

This reaction requires a small amount of water, i.e. 2 to 8 parts of the reaction mixture.
It is most suitably carried out in the presence of water, preferably 4 to 6 times tX. 111 for US Patent in 111M
As disclosed in No. 383.081, the use of such water has very favorable effects in systems of the nature to which the present invention is concerned.

The carbon monoxide that is mixed with the hydrogen in the reaction zone is preferably in substantially pure form, as commercially available, but may optionally be supplemented with inert diluents such as carbon dioxide, nitrogen, methane and It can contain a rare gas. The presence of such an inert diluent allows calyt=
The reaction is unaffected, but the total pressure in the reaction zone must be increased to maintain the desired carbon monoxide partial pressure.

The cocatalyst component can be in any convenient form, i.e. in the zero-valent state f*
can be used in any high-valence form. For example, the cocatalyst components such as nickel and molybdenum or tungsten or gold in finely ground form can be organic or inorganic compounds convenient for introduction into the reaction system. For example, typical compounds include carbonate, oxide, hydroxide, bromide, iodide, chloride, oxyhalide, hydride, lower alkoxide (methoxide), phenoxide, or calxylate ion. Alkanoic acids derived from 1 to 2 carbon atoms include, for example, acetate, butyrate, decanoate, roughlate, benzoate, etc., 7Mo, W, and N4 carboxylates. Complexes of optional cocatalyst components can also be used in the same ai. for example,
Carbonyl and alkyl metals, as well as chelates, associative compounds and enol salts can be used. As an example of another complex, His-(triphenylphosphine)nickel cyalou? Similar complexes of nickel, tri7-clopentadienyl, trinickel, tetrakis(triphenylphosphite)nickel, and other components include molybdenum hexacarbomol and tungsten hexacarbonyl.

Included among the catalyst components listed above are metal cocatalyst components that include a mechanical promoter ligand derived from an organic promoter as described below.

Particularly preferred are the single elemental forms, halides, especially iodides, and organic salts, such as the corresponding monocarboxylic salts, such as the corresponding monocarboxylic salts. It is the land of acid.

It will be appreciated that the compounds and complexes described above are merely illustrative of some suitable forms of cocatalyst components and are not intended to be limiting.

The co-catalysts used above do not need to be purified beyond the impurities normally associated with commercially available gold pA or d metal compounds.

Preferably, the organophosphorus promoter is a phosphine, e.g.
has the formula P-)13f, where Bl, R2 and R3 are the same and may be different or have different R values; An amide group such as hexamethylphosphoric triamide, or a halogen atom, with VC preferably containing from 1 to 20 carbon atoms in the case of alkyl and cycloalkyl groups, and from 6 to 18 carbon atoms in the case of aryl groups. is preferred. Representative hydrocarbylphosphines include trimethylphosphine, trizolobylphosphine, tricyclohexylphosphine and triphenylphosphine. Preferably, the organic nitrogen promoter is
c is a polyfunctional nitrogen-containing compound such as an amide, a polyamine such as a hydroxyamine, a ketoamine, a diamine and a triamine, or a nine-containing compound containing two or more other functional groups. Typical organic 9-element accelerators include 2-hydroxybiridine, 8-quinolitool, 1
-Methylpyrrolidinone, 2-imidazolitone, N, N-
These include dimethylarecetamide, dicyclohexylacetamide, dicyclohexylmethylamine, 2,6-diamitubiridine, 2-quinolitool%N, N-diethyltoluamide, and imidazole.

Generally, organic promoters are added to the catalyst system independently, but in complexes with any of the cocatalyst metals, such as bis(triphenylphosphine)nickel dicarbonyl and tetrakis(
It is also possible to add it as nickel (triphenylphosphite). Free organic promoters and complex promoters can be used as well. If a complex of an organic promoter and a cocatalyst metal is used, a free organic promoter can also be added.

The amount of each cocatalyst component used is by no means critical and is not an important parameter of the process of the invention and can vary over a wide range. As will be appreciated by those skilled in the art, the rate of reaction is affected by the amount of catalyst, so the type of catalyst used will be such as to provide the appropriate and reasonable rate of reaction desired. However, since basically any amount of catalyst promotes the basic reaction, any amount can be considered a catalytically effective amount.

However, in general, each catalyst component contains 10 to io of alcohol.
, ooo mole afc 1 mole negative, preferably 100 to 5,000 moles of alcohol*D1 mole b Most preferably 1 mole is used per 300 to 1,000 moles of alcohol.

The ratio of nickel to second cocatalyst component can vary. Generally, the second cocatalyst component 0()1 to 100 moles6
ff 1 mole of nickel, preferably 1 mole of nickel per 01 to 20 moles of second cocatalyst component, most preferably 1 mole of nickel per 1 to 10 moles of second cocatalyst component.
Use moles.

The charge of the organic promoter can also vary widely, but typically amounts of 1 mole per 0.1 to 10 moles of cocatalyst component are used.

Although the amount of iodide component can also be varied greatly,
Generally, there should be an amount of at least 10 moles (calculated in ■) per 100 moles of alcohol. Generally 1
10 to 50 moles of lyodide per 100 moles of alcohol are used, preferably 17 to 35 moles per 100 moles. Usually 100 moles of alcohol 67'? ! No more than 200 moles of iodide is used. However, it is readily apparent that the iodide component need not be added to the system as hydrocarbyl iodide, but as another organic iodide, or as hydrogen iodide or other inorganic iodide such as tM (e.g. alkali metal salts). It can be added as iodine (eg, other metal salts) or even as iodine in elemental form.

A specific embodiment of the catalyst consisting of a tungsten-nickel cocatalyst component, an organic promoter component, and an iodide component can be represented by X:T:Z:Q. In this formula, X is molybdenum or tungsten, T or nickel; . Z is a source of iodide and is hydrogen iodide, iodine, alkyl iodide where the alkyl group contains 1 to 20 carbon atoms, or an alkali metal iodide. Q is an organic phosphorus compound or an organic nitrogen compound in which phosphorus and nitrogen are trivalent. Preferred forms of use include the nitrogen compounds and phosphorus compounds described above, and the most preferred form of Q is the phosphine having the formula R1P-H13 k.
It's in. The molar ratio of X and T is (01-10) = 1
, the molar ratio of X+T and Q is (005-20): the molar ratio of IZ and X0T is (1-1,000):1.

Obviously, the reaction described above is suitable for continuous operation.

In its continuous operation, the reactants, water, and catalyst are continuously fed to a suitable reaction zone, and the reaction mixture is continuously distilled to separate volatile organic components consisting essentially of calzenic acid. The final product is recovered, other organic components are recycled and, in the case of liquid phase reactions, the residual catalyst containing fractions is also recycled.

The present invention will be more fully understood by the following examples. However, these examples are intended to be illustrative only and should not be construed as limiting the invention.

Example 1 The apparatus used in this example was a 1 liter autoclave with an electric heating jacket, a magnetic stirrer, gas and liquid supply lines, and gas-to-gas at the vapor-liquid interface.
A liquid take-off line is attached. This device is heated to a temperature of 2
It was operated at 10 DEG C. with a partial pressure of carbon oxide of 58.0 psi (825 psi) and a partial pressure of hydrogen of 139 psi (198 psi), thus a ratio of hydrogen partial pressure to carbon monoxide partial pressure of 0.24.

- The partial pressures of carbon oxide and hydrogen are continuous, with the required t' of these two gases.

Maintained by each feed.

The feed stream was fed at a rate of 720 f/hr.

This feed stream consisted of 252 Chongkei Tanol, 37% by weight methyl iodide, 9.6% by weight methyl acetate, 12.2% by weight.
It is a mixture of acetic acid and 46% water by weight as well as 0.2% nickel (added as nickel iodide), 0.3% molybdenum (added as molybdenum carbonyl) and 5% by weight triphenylphosphine.

After reaching steady-state operating conditions, the reaction was run continuously for about 16 hours. The collected effluent was subjected to gas chromatography (G,
O, ) K was analyzed and found that acetic acid was produced from methanol at a rate of 12.1 gmol/hour/liter.
Comparative Example A The method and apparatus described in Example 1 were also used in this experiment, but the carbon oxide partial pressure was 35.9 (51° psi).
The difference is that the hydrogen partial pressure is 27.8 (395 psi), so the ratio of the hydrogen partial pressure to the carbon monoxide partial pressure is 0.77. The composition of the feed stream was substantially the same as in Example 1 and was fed at a rate of Q54 or/hour. Analysis of the effluent revealed that the rate of production of acetic acid from methanol had decreased to 11t6.8/rammol/hour/liter.

Comparative Example B This experiment also used the method and apparatus described in Example 1, but the -carbon oxide partial pressure was 844 yen (1200 psi).
), and no hydrogen is added to the system, so the hydrogen partial pressure is O
The difference is that it is ¥I (Ops+). The composition of the feed stream is substantially the same as in Example 1, and this feed stream is fed at a rate of 30,097 hours.
Masamitsu Sawa and 1 other person July 7, 1945 Senior official of the Patent Office 1, Tenant's table of works, Ganshota g - 1IL7Δri No. 2, name of INH 3.Relationship with the supplementary person case Yamasara X

Claims (2)

[Claims] (1) The reaction is carried out in the presence of hydrogen, in the presence of a catalyst containing a molybdenum-nickel or tungcuten-nickel cocatalyst component, in the presence of iodide, and in the presence of a promoter containing an organic phosphorus compound or an organic nitrogen compound. Ratio of hydrogen partial pressure to carbon monoxide partial pressure in the band t 0.05 to 0.
4. Methanol? - A method for producing acetic acid, characterized by reacting it with carbon oxide. (2) The method according to claim 1, wherein the ratio of hydrogen partial pressure to carbon monoxide partial pressure in the reaction zone is from 0.15 to 0.30.