DE2535471A1 - METHOD OF MANUFACTURING AETHERS - Google Patents

Description

Patent assessor Hamburg, July 15, 1975

Dr. Gerhard Schupfner 54-7 / ik

German Texaco AG

2000 Hamburg 13

Mittelweg 180 T 75 024- D (D 74-, 140-F)

TEXACO DEVELOPMENT CORPORATION

135 East 42nd Street
New York, JF.Y. 10017

UNITED STATES.

Process for the production of ethers

The invention relates to a method for producing ethers, in particular asymmetrical ethers.

Ethers, including asymmetrical ones, are known to be produced by reacting an alcohol with the same or a other alcohol prepared in the presence of a catalyst and / or a condensing agent. The reaction mixture is then separated and treated further to obtain the desired product. Such further processing concludes generally one or more distillation operations.

The invention is now based on the object of a method for the production of ethers, in particular asymmetrical ones To create ethers in which the ethers are obtained in high yields and in a high degree of purity, without one or more times must be distilled.

- 2 - 609811/1008

The object is achieved by a method for producing ethers, in particular asymmetrical ethers, which characterized in that a water-soluble alcohol is used as the first reactant and a second reactant an olefin or a water-insoluble alcohol in the presence of an ion exchange resin etherification catalyst converts the resulting reaction mixture, which unreacted water-soluble alcohol and the desired ether contains, brings into contact with water in the presence of one or a mixture of gasoline hydrocarbons, and thereafter the aqueous, water-soluble alcohol-containing phase from the gasoline hydrocarbon phase, that of the water-soluble Contains alcohol-free product ether, separates.

In the practical implementation of the process according to the invention for the production of ethers, the first reactant is a water-soluble alcohol is used. This can be a monohydroxy or a polyhydroxy alcohol. Examples for suitable monohydroxy alcohols are: methanol, ethanol, n-propanol, iso-propanol, n-butanol, isobutanol, sec-butanol, tert-butanol, benzyl alcohol. Examples of polyhydroxy alcohols are: ethylene glycol, propylene glycol, pentaerythritol, glycerine, Trimethylol propane, sorbitol.

The preferred water-soluble alcohol is an aliphatic alcohol with 1-6 carbon atoms, in particular a monohydroxy alcohol. Monohydric aliphatic alcohols with fewer than 4 carbon atoms, in particular methanol, are particularly preferred.

According to a preferred embodiment of the invention, an asymmetrical ether is produced, one of which is a hydrocarbon radical derived from a water-soluble and the second hydrocarbon from a water-insoluble alcohol. The advantages of the method according to the invention occur in the The production of asymmetrical ethers is particularly evident.

609811/1008

- 35 -

Preferably, an Ither is produced in which the from hydrocarbon residue from water-insoluble alcohol has at least 3 carbon atoms more than the hydrocarbon residue, which comes from the water-soluble alcohol.

The second reactant can be selected from the group consisting of olefins and water-insoluble alcohols. When the second reactant is an olefin, the olefin can have one, two, three or more double bonds. Monoolefins, i.e., olefins with a double bond, are preferred. Examples are: ethylene, propylene, n-butylene, iso-butylene, iso-amylenes, styrene, phenyl-propylene. Aliphatic monoolefins are particularly preferred, especially those which have a tertiary carbon atom, such as iso-butylene, iso-hexylene. Isobutylene is preferred.

The second reactant, like the other components of the system, need not be pure. As a second reactant suitable is e.g. the isobutylene of a stream which occurs in a refinery and is designated as a C ^ stream, which is approximately can have the following composition:

Table I.

component %

Isobutane 40.5

Isobutylene 10.0

1-butene 7.8

2-butenes (cis-trans) 12.1

Other 29.6

A total of 100

As can be seen from the table, such a current can be components that are reactants (e.g. iso-butylene) and components that are inert. (e.g. isobutane). In this Pail the inert materials from the final product

- 4 609811/1008

removed by stripping.

If the second reactant is a water-insoluble alcohol, an aliphatic monohydroxy alcohol with at least 5 carbon atoms, preferably 6-10 carbon atoms, is preferred. The melting point of the alcohol should be such that the alcohol at room temperatures of 20 -. 30 ⁰ C is liquid. Examples of such alcohols are n-hexanol, n-pentanol, octanol-1, decanol-1, dodecanol-1, 2-ethylhexanol.

The implementation can take place under the following table II

Tabel ^ * F ~ J ^ H "HH h ^ hhhhhi» w »» - ^ ir ^^ H ^^^ - ^ r ^ B ^^ ^
II More preferred
value Reaction
bedinPf'TiFrai Further
area Preferred
area 93 Temperature ⁰ C 38-150 65 - 121 21.1 Pressure, atü 3.52-52.7 3.52-35.2 17th First reactant -
Parts -5-50 5-20 33 Second reactant
Parts 20-90 20-50 50 Petrol hydrocarbon
fabrics - Parts 5-100 40-90

A special feature of the process according to the invention is that the molar ratio of first reactants to second reactant is at least 0.8. It has been found, however, that the method works with greater advantage when the ratio is above 1 and preferably 1.2-4.0, especially 2.3. The presence of an excess on the first reactant, e.g. methanol, facilitates the agreement of the desired asymmetrical Ither and increases the Lifetime and selectivity of the catalysts used.

The etherification is preferably carried out in the presence of a solid ion exchange resin etherification catalyst.

- 5 -609811/1008

These catalysts are preferably carbon-containing materials of relatively high molecular weight which have at least one - SO ^ H group as a functional group. Examples of these catalysts are sulfonated coals ( ^w Zeo-Karb H, ⁿ "Nalcite X" and "Nalcite AX"), which are produced by treating bituminous coals with sulfuric acid. These materials are usually available in neutralized form and must then be converted into the Η form before use by treatment with a strong mineral acid, such as hydrochloric acid and subsequent washing with water to remove the sodium and chlorine ions.

Sulfonated ion exchange resins are particularly preferred catalysts for the process according to the invention. Such Catalysts are e.g. the reaction products of phenol-formaldehyde resins and sulfuric acid ("Amberlite IR-I", "Amberlite IR-100" and "Nalcite MZ"). They are also suitable arulfonated resinous polymers of coumarone-indene and Cyclopentadiene; sulfonated polymers of coumarone-indene and furfural; sulfonated polymers of coumarone indene with cyclopentadiene and furfural; and sulfonated polymers of cyclopentadiene with furfural.

The most preferred cation exchange resins are strongly acidic ion exchangers, which essentially consist of sulfonated polystyrene resins, for example a polystyrene matrix crosslinked with divinylbenzene in which 0.5-20%, preferably 4-16% divinylbenzene are polymerized, and which carries ionizable or functional nuclear sulfonic acid groups. These resins are commercially available under various trademark names such as "Dowex 50", Nalcite HCS "and" Amberlyst 15. "The commercial products have a solvent content of about 50 % and can be used as is or after the solvent has been removed of the resins is, for example, between 1.980 and 0.928 mm (10-50 mesh United States Sieve Series).

- 6 609811/1008

- ο -

The reaction can either be carried out in a stirrer Sump reactor or in a plague bed reactor with continuous flow. The catalyst concentration must be high enough so that the desired catalytic ^ Effect occurs. In general, the catalyst concentration (based on the dry weight of the catalyst) between 0.5 and 50, preferably 1 - 25% by weight of the reactor content

The gasoline hydrocarbon can already be present during the etherification reaction, but it can also be added before or during the contacting with water. As used herein, the term "gasoline hydrocarbon" or "gasoline hydrocarbon blend" means a component which is substantially miscible with the product ether and gasoline and substantially immiscible with water and, when mixed with a gasoline, is not an undesirable component. In a preferred embodiment of the invention, the gasoline hydrocarbon consists of more than 30%, preferably more than 50 %, of aromatic components. It can be largely pure benzene, toluene, xylenes and the like.

The gasoline hydrocarbon can also be a fuel component (i.e., a hydrocarbon including an alkylate or naphtha), from which a fuel can be made after mixing with other components. It can be an alkylate, a reformate, a fluid-cracked light or heavy naphtha, a naphtha that isomerized by hydrocracking and the like. has been obtained. In a preferred embodiment, the gasoline hydrocarbon is itself a Fuel, leaded or unleaded.

The petrol hydrocarbon can, for example, be one of the fuels listed below:

609811/1008

characteristics

Tabel III

Carburetor fuel

Motor alkylate

78 0.68

90.8 89.5

⁰ C

28.5

45.0 55.5 67.8 81.7 92.2

98.5 105.9 110.0 118.9 147.8 183.9 195.5 96.5

2.5

So you can use the first reactant for the etherification, the add the second reactants and the gasoline hydrocarbon. During the Heaktion the desired aether is passed through Conversion of e.g. methanol with isobutene to methyl tert-butyl ether educated.

The raw product stream contains about 10-50%, preferably 15-50%, for example about 50 % of the desired ether, 1-4%, preferably 2-3% of the second reactant and 1-40%, preferably 2-20%, for example 2, 3% of the water soluble

Specific weight according to APJ 60.8 Eeid steam pressure 0.77 (kg / cm2) Eesearch octane number EOZ 91.0 Engine octane number MOZ 85.0 ASTM DISTILLATION Weight at ° c Start of boiling 52.2 5 45.6 10 55.9 20th 72.2 50 90.0 40 104.4 50 114.4 60 125.6 70 138.3 80 151.1 90 167.8 95 185.6 End point 188.9 recovered 96.0 loss 2.9

609811/1008

Alcohol and additionally the petrol hydrocarbon

When the etherification reaction in the absence of the gasoline hydrocarbon has been carried out, the gasoline hydrocarbon is added to the reaction mixture at this point.

Water in quantities of 10-100, preferably 30-75 parts, say 50 parts of, for example, added to the reaction mixture at a temperature between about 15 and 38 ° C, preferably 26-32 ° C at 29.5 ⁰ C and the The whole thing is intensely mixed. It is a feature of the process of the present invention that the contacting of the reaction mixture with the water is effected rapidly. A small number of contact levels can be used, but a single contact level is preferred.

During the contacting, an aqueous extract is used in an amount of 30-130 parts, preferably 50-95 parts, for example 70 parts, of 1-20 parts, preferably 3-10 parts, for example 5 parts, of the water-soluble alcohol, e.g. methanol. The raffinate contains practically no water soluble alcohol (no first reactant; 0-10 parts, preferably 0-5 parts, e.g. 2-7 parts of the second reactants, 5-50 parts, preferably 10-30 parts, e.g. 15 parts of the product ether and 5-100 parts, preferably 40-90 parts, e.g. 50 parts of the gasoline hydrocarbon.

The presence of the gasoline hydrocarbon during the Bringing the organic phase, to which the gasoline hydrocarbon belongs, into contact with water holds the product ether dissolved in the organic phase. If there were no gasoline hydrocarbon present, a significant proportion of the ither would be extracted into the aqueous phase and would be lost to the system (or it would have to be specially worked up and distilled to win the ether).

The raffinate is best made by separating it from the

60981 1/1008

heavier aqueous phase isolated. It is a feature of the process of the invention that the product ether in yields of over 80%, often even in stochiometrisoher Yield is obtained. Another feature of the invention Method is that the product ether is practical completely free of undesirable compounds, including the first reactants (e.g. methanol) and Vasser is.

A particular advantage to which the process according to the invention leads is that high yields of pure product ether (in a gasoline hydrocarbon) can be obtained in a simple manner without, as was previously inevitable, must be distilled. Although it is possible to separate the ether from the gasoline hydrocarbon, it should in most Cases will be redundant. The solution of the ether, e.g. methyl tert-butyl ether in a gasoline hydrocarbon can be added directly to a fuel in order to improve the To contribute octane number (BOZ and MOZ) of the fuel. If a C ^ -stream has been assumed as the second reactant, which also contains undesirable lighter components, the ether in the gasoline hydrocarbon can stabilize it to remove such components (e.g. isobutane).

To further illustrate the invention, the following examples are given, in which all parts are parts by weight mean unless otherwise stated.

Example 1 (a preferred embodiment of the invention) 17 parts (0.53 moles) of methano] | absolute, 33 parts (0.59 moles) of isobutylene and 50 parts of a gasoline hydrocarbon of the composition shown in Table III were continuously passed through for 18 hours bed of 14.5 parts of an ion exchanger, namely Amberlyst 15 from Rohm and Haas Inc. at 93 ⁰ C and 21.1 kg / cm ² conducted. Amberlyst 15 is a strongly acidic cation exchange resin, a sulfonated,

- 10-Ö U '} :.! M J 1 0 Ü y

Polystyrene resin crosslinked with divinylbenzene. The barely speed the total feed (volume feed per volume x catalyst per hour) was 6.9 VolAol / h. That The molar ratio of methanol to isobutylene was 0.9

The crude product was 104 parts of a mixture which contained 2.3 parts of methanol, 2.7 parts of diisobutylene, 49.3 parts of methyl tert-butyl ether and 50 parts of a gasoline hydrocarbon. This product was ^{brought into contact in batches at 32 0} O with 50 parts of water in a washing stage. The aqueous extract contained 50 parts of water and 2.3 parts of methanol. The raffinate contained 50 parts of gasoline hydrocarbon, 49.3 parts of methyl tert-butyl ether, 2.7 parts of diisobutylene and 0 part of methanol. The ether yield, based on the amount of methanol used, was practically stoichiometric. The actually determined yield was 106%.

The washed and debutanized product gasoline had the following values (the numbers in brackets indicate the values of the gasoline hydrocarbon used): RON 103.2 (91.0); MOZ 89.8 (83.0); Reid vapor pressure, kg / cm ² , 0.74 (0.81).

Example 2 (comparative example)

Example 1 was repeated except that the 50 parts gasoline hydrocarbon in the feed stream was replaced by 50 parts Replaced n-pentane.

The crude product contained 94.6 parts of a mixture of one part of methanol, 22.7 parts of diisobutylene and 20.9 parts of methyl tert-butyl ether and 50 parts of n-pentane. After washing with water, the raffinate contained 50 parts of n-pentane, 21 parts Methyl ether, 22.7 parts diisobutylene and no methanol. The yield of Ither was 43.5% of the yield in Example 1.

A comparison of Examples 1 and 2 shows that the inventive Process allows a stoichiometric yield (i.e. 100% yield), while in the comparative example

~ -11-

- 11 not even a 50 # yield is achieved

Example 3 (according to the invention)

Example 1 was repeated except that the feed stream (the one having a space flow rate of 4.7 Vol / Vol / h was passed through the catalyst bed) in 100 Ropes 8.2 parts of methanol, 61.2 parts of the C ^ stream, the composition of which is given in Table I and the approx 18.3 parts of olefin corresponds, and 30.6 parts of the fuel, the composition of which can be found in Table III is contained.

The crude product contained 3.5 parts of methanol, 10.6 parts of methyl tert-butyl ether, 0.3 parts of diisobutylene, 55 parts of carbon stream and 30.6 parts of fuel.

After a single wash with water, the raffinate contained 55 parts of C ^ stream, 0 parts of methanol, and 10.5 parts of methyl tert-butyl ether and 0.3 part of diisobutylene. The yield of ether was 91, ^% -

The washed and debutanized product fuel had the following analysis values: RON 97.5, MON 86.0, Reid vapor pressure, kg / cm ² 0.88.

Results approximately the same as in Example 1 were obtained with receive the input materials listed below:

example Water soluble Second Hydrocarbon alcohol Reactant material IV n-propanol Isobutylene fuel 7th Methanol Isobutylene toluene VI Methanol n-pentanol Xylenes VII Methanol n-hexanol benzene VIII Methanol 2-ethylhexano 1 fuel IX n-propanol Isoamylene fuel X Ethanol Propylene fuel XI Methanol Isoamylene fuel

- 12-609811 / 1008

Example XII-XVI

In these examples, water-soluble alcohols were used Formation of ethers used. In Examples 12, 13 and 14 the catalyst was Amberlyst 15 »a sulfonated polystyrene resin. In Examples 15 and 16, the catalyst Dowex 50 »was also a sulfonated polystyrene resin, used.

Examples

In these examples, a G ₁ stream according to Table I, methanol and the motor alkylate of the composition according to Table III were used as starting materials. The product was methyl tert-butyl ether in motor alkylate. The reaction conditions, the composition of the feed stream, crude product and product after washing with an equivalent amount of water is summarized in Table 17 below.

example

In this example, the C ^ stream and methanol were used. The fuel according to Table III was added in an amount of 2 volumes per volume of the reaction mixture. The overall mix was then washed with an equivalent amount of water to obtain the product ether in fuel.

example

In this example, the starting _{mixture consisted of the C 2} stream according to Table I, ethanol and fuel according to Table III. After the completion of the reaction, the mixture was washed with the equivalent amount of water to obtain the product ether in the fuel.

example

In this example, a starting mixture of isoamylene, methanol and xylenes was used. After the reaction has ended the mixture was washed with the equivalent amount of water to obtain the product ether in xylenes.

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609811/1008

Examples
Temp. ⁰ O
Pressure (atü)

- 13 (Table IV

XII

Room speed d. Feed vol / vol / h 4.7

Test duration in hours 27

Charge (wt%)

Methanol 8.2

Ethanol

Isobutylene

Isoamylene

Cv current

fuel

Alkylate

Xylenes

Molar ratio (alcohol to isoolefin)

Crude product (wt .-%)

Methanol

Ethanol

tert -butyl methyl ether tert-butyl ethyl ether tert. -Amyl methyl ether

After the water wash

Methanol

Ethanol

tert -butyl methyl ether tert-butyl ethyl ether tert -amyl methyl ether ether yield 95 RON 99.6

MON 92.0

61.2

30.6

2.3

5.0 15.9

XIII XIV XV XVI

93 93 121 93 21 21 21 21

42

6.0 5.0 5.0 42 20 20

9.8 10.0

83.95 90.0 70 100 20

6.25

30 2.0 1.8 1.7 1.75

13.2 15.0 - 12.5

4.0 30.2 27.5

13.0

57.0

1.1

15.7 27.9 27.7, 13.0

57.0

95 100 100 80 102.0 96.6
92.0 85.8

- 14 -

609811/1008

Claims (11)

" ¹⁴ ~ O? 75 024 D Claims M) / Process for the production of ethers, in particular ^ - ^ symmetrical ethers, characterized in that a water-soluble reactant is used as the first reactant Alcohol and, as the second reactant, an olefin or a water-insoluble alcohol in the presence of one ion exchange resin etherification catalyst converts, the reaction mixture obtained, which unreacted water-soluble alcohol and the desired Ither contains, with water in the presence of gasoline hydrocarbon "brings in contact" and then the aqueous, the water-soluble alcohol containing Phase from the gasoline hydrocarbon phase, which contains the product ether free of water-soluble alcohol, separates. 2) Method according to claim 1, characterized in that one is the first Eeaktanten uses a monohydroxy alcohol with 1-6, in particular 1-3, carbon atoms. 3) Method according to claim 2, characterized in that one is the first Eeactanten Methanol uses. 4) Method according to one of the preceding claims, characterized in that that the second reactant is an olefin with a double bond and in particular a tertiary carbon atom begins. - 15- 6 & 9 8 1 1/1008 5) Process according to claim 4, characterized in that isobutene is used as the second reactant. 6) Method according to one of claims 1-3 »characterized in that that a water-insoluble monohydric alcohol with at least 5 carbon atoms is used as the second reactant " 7) Method according to claim 6, characterized in that one is the second Reactants a hexanol uses 8) Method according to one of the preceding claims, characterized in that the gasoline hydrocarbon is a carburetor fuel, hydrocarbons with a proportion of aromatics with 6-11 carbon atoms of at least 30 % or a proportion of benzene and / or toluene and / or xylene is used. 9) Method according to one of the preceding claims, characterized in that that one carries out the etherification in the presence of gasoline hydrocarbons. 10) Method according to one of claims 1-8, characterized in that that one or the gasoline hydrocarbons the reaction mixture after completion of the etherification and added before contact with water. 11) Method according to claim 1, characterized in that methanol and isobutylene are used in the presence of a carburetor fuel and 6098 11/1008 - 16-253R471 a cation exchange resin etherification catalyst undertakes the reaction mixture obtained from unreacted methanol, the desired Brings methyl tert-butyl ether and carburetor fuel into contact with water and the carburetor fuel-ether-raffinate phase separated from the methanol-containing aqueous extract phase. 609811/1008