DE1568415C3

DE1568415C3 - Process for the purification of synthetically produced primary monoalcohols

Info

Publication number: DE1568415C3
Application number: DE19661568415
Authority: DE
Inventors: Friedrich Dr. 2000 Hamburg; Erhard Karl Dr. 2101 Dibbersen; Fuchs Gundolf Dr. 2111 Steinbeck Engelhardt
Original assignee: Deutsche Texaco AG
Current assignee: Wintershall Dea Deutschland AG
Priority date: 1966-09-24
Filing date: 1966-09-24
Publication date: 1976-04-15

Description

in Berührung bringt. Die Berührungszeit des Alkohols mit dem Katalysator kann unterschiedlich gestaltet werden und richtet sich im wesentlichen nach der gewählten Katalysatorart, der Temperatur und dem Diolgehalt des eingesetzten Alkohols.brings in touch. The contact time of the alcohol with the catalyst can be designed differently and depends essentially on the selected Type of catalyst, the temperature and the diol content of the alcohol used.

Ähnliches gilt für die Wahl der Temperatur. Diese richtet sich gleichfalls nach der Art des Katalysators. So ist es vorteilhaft, bei Titan- und Zirkon-Katalysatoren höhere Temperaturen, beispielsweise 230 bis 250⁰C anzuwenden und bei Alumini umoxyd-Katalysatoren im Bereich von 170 bis 22O⁰C zu arbeiten. Was den Druck betrifft, so arbeitet man vorteilhaft unter Normaldruck. Man kann jedoch auch unter erhöhtem Druck arbeiten, insbesondere, wenn man die Entfernung der Diole bei kurzkettigen Alkoholen durchführen will. Schließlich kann man die Diolentfernung auch unter vermindertem Druck durchführen, insbesondere dann, wenn man sehr langkettige Alkohole reinigen will.The same applies to the choice of temperature. This also depends on the type of catalyst. Thus, it is advantageous at higher titanium and zirconium catalysts, temperatures, for example 230 applied to 250 ⁰ C and work umoxyd catalysts in the range of 170 to 22O ⁰ C for Alumini. As far as the pressure is concerned, it is advantageous to work under normal pressure. However, you can also work under increased pressure, especially if you want to remove the diols from short-chain alcohols. Finally, the diol can also be removed under reduced pressure, especially if you want to purify very long-chain alcohols.

Das vorliegende Verfahren sei an Hand nachfolgender Beispiele näher erläutert:The present process is explained in more detail using the following examples:

Examples

1) Ein nach dem Ziegler-Verfahren gewonnener Alkoholschnitt mit einer Kohlenstoffzahl C₁₂-Cj₄ hat eine OH-Zahl von 283 und einen Gehalt an Diolen von 1,0 Gewichtsprozent. Bei den Diolen handelt es sich um ein Isomerengemisch mit OH-Gruppen, vorwiegend in 1,2- und 1,3-Stellung. Dieses Alkoholgemisch wird in einem Rührwerkskessel mit 1 % Zirkontetrahydroxyd bei einer Temperatur von 230°C 3 Std. gerührt. Danach wird durch Filtration der Katalysator abgetrennt. Nach dieser Behandlung hat der Alkohol eine OH-Zahl von 276 und einen Diolgehalt von <0,05%.1) An alcohol cut obtained by the Ziegler process with a carbon number C ₁₂ -Cj ₄ has an OH number of 283 and a diol content of 1.0 percent by weight. The diols are a mixture of isomers with OH groups, predominantly in the 1,2- and 1,3-positions. This alcohol mixture is stirred in a stirred tank with 1% zirconium tetrahydroxide at a temperature of 230 ° C. for 3 hours. The catalyst is then separated off by filtration. After this treatment, the alcohol has an OH number of 276 and a diol content of <0.05%.

2) Nach dem gleichen Verfahren, wie im Beispiel 1 beschrieben, wird ein Alkoholschnitt C₁₆/₁₈ mit einer OH-Zahl von 222 und einem Diolgehalt von 1,2% bei 230⁰C 6 Std. unter Verwendung von 1% Titantetrahydroxyd behandelt. Der abfilr trierte Alkohol hat eine OH-Zahl von 216 bei einem Diolgehalt von <0,05%.2) according to the same method as in Example 1, an alcohol-section C _{_16/18} having an OH number of 222 and a diol content of 1.2% at 230 ⁰ C for 6 h. Treated using 1% Titantetrahydroxyd. The alcohol filtered off has an OH number of 216 with a diol content of <0.05%.

3) Nach dem gleichen Verfahren, wie im Beispiel 1 beschrieben, wird ein Alkoholschnitt C_8/l8 mit einer OH-Zahl von 296 und einem Diolgehalt von 0,8% mit 2%y-Al₂O₃ in Pulverform bei 220⁰C 6 Std. gerührt. Dabei sinkt der Diolgehalt auf <0,05% bei einer OH-Zahl von 290.Described 3) By the same procedure as in Example 1, an alcohol cut C _{8 / l8} having an OH number of 296 and a diol content of 0.8% with 2% y-Al ₂ O ₃ in powder form at 220 ⁰ C Stirred for 6 hours. The diol content drops to <0.05% with an OH number of 290.

4) In einem senkrecht stehenden Reaktor läßt man einen Alkoholschnitt C₁₂/₁₄ mit gleichen Ausgangsdaten wie im Beispiel 1 bei 180⁰C über einen fest angeordneten y-Al₂O₃-Kontakt mit einer RG von 0,5 Vol./Vol. Katalysator/h rieseln. Die OH-Zahl des behandelten Produktes beträgt 275, der Diolgehalt sinkt auf <0,05%.4) In a vertical reactor section is allowed an alcohol C _{_12/14} with the same starting data as in Example 1 at 180 ⁰ C for a fixed y-Al ₂ O ₃ catalyst at SV 0.5 vol./vol. Catalyst / h trickle. The OH number of the treated product is 275, the diol content drops to <0.05%.

5) In einer gleichen Apparatur, wie im Beispiel 4 beschrieben, wird der Alkoholschnitt C₁₂/₁₄ — gleiche Ausgangsdaten wie im Beispiel 1 — bei 200°C und einer RG von 1 Vol./Vol. Katalysator/h von unten durch die Säule gepumpt (Sumpfphasenbehandlung). Die OH-Zahl des behandelten Produktes beträgt 275, der Diolgehalt sinkt auf<0,05%.5) In a similar apparatus as described in Example 4, the alcohol-section C is _{_12/14} - same data as in Example 1 - at 200 ° C and an RG of 1 vol./vol. Catalyst / h is pumped through the column from below (bottom phase treatment). The OH number of the treated product is 275, the diol content drops to <0.05%.

Die Beispiele zeigen, daß die Hydroylzahlen der behandelten Alkoholschnitte praktisch nicht weiter abnehmen als die Entfernung der sekundären OH-Gruppe der Diole erwarten läßt.The examples show that the hydroyl numbers of the treated alcohol cuts practically do not go any further decrease than the removal of the secondary OH group of the diols suggests.

6) Nach dem gleichen Verfahren, wie im Beispiel 1 beschrieben, wird ein Alkoholschnitt mit einer Kohlenstoffzahl C₁₂-C₁₄, einer OH-Zahl von 286 und einem Diolgehalt von 0,85 % mit 2 % y-Aluminiumoxyd in Pulverform bei 22O⁰C 6 Std. lang gerührt. Nach Abfiltratiön des Katalysators wird ein Produkt erhalten, dessen Diolgehalt auf <0,05 % gesunken ist bei einer OH-Zahl von 276, einer Br-Zahl von 0,79 mg Br/100 mg und einer CO-Zahl von 1100 ppm.6) Using the same method as described in Example 1, an alcohol cut with a carbon number of C ₁₂ -C ₁₄ , an OH number of 286 and a diol content of 0.85% with 2% γ-aluminum oxide in powder form at 220 ⁰ C stirred for 6 hours. After the catalyst has been filtered off, a product is obtained whose diol content has fallen to <0.05% with an OH number of 276, a Br number of 0.79 mg Br / 100 mg and a CO number of 1100 ppm.

Nach der Hydrierung mit einem handelsüblichen Nickelkontakt hat der Alkohol folgende Daten: Diolgehalt <0,05 %, OH-Zahl 276, Br-Zahl 0,1 mg Br/100 mg, CO-Zahl 127 ppm.After hydrogenation with a commercially available nickel contact, the alcohol has the following data: Diol content <0.05%, OH number 276, Br number 0.1 mg Br / 100 mg, CO number 127 ppm.

Claims

1 2 the unsaturated compounds formed as a result of the patent claims: are then hydrogenated. The selective dehydration according to the invention takes place in the presence of

1. A process for the purification of synthetic oxidic compounds of the elements aluminum, primary monoalcohols produced with more 5 zirconium or titanium, as catalysts in Temperaturais 4 carbon atoms by catalytic hy- range 130-280 ⁰ C. This converts drierung, characterized in that from the diols unsaturated monoalcohols which, depending on the position that the secondary OH-elevated temperature had in the diol by means of oxidic compounds, partially in saturated genes of the elements zirconium, titanium or especially io rearrange aldehydes. Both of the unusual aluminum produced in this way are selectively freed from the saturated compounds they contain are freed in the subsequent diol impurities and then hydrogenation, which are catalytically hydrogenated using any of the known methods. can be carried out in saturated mono-

2. The method according to claim 1, characterized thereby converted alcohols.

draws that the selective dehydration of 15 The catalytic dehydration of alcohols

Raw alcohols by means of gamma-aluminum oxide are known. It is also known to use diols with a

is taken. secondary OH group in such a way as to dehydrate

3. The method according to claim 1 or 2, characterized in that only the secondary OH group is eliminated characterized in that the catalytic dehydration and the diol in an unsaturated monoalcohol at a temperature of 130 to 280, is converted into 20. But that it succeeds, little special 170 to 220 ° C takes place. Amounts of diol in the presence of monoalcohols like this

To dehydrate selectively so that there is no change in the monoalcohols is extremely

surprising and was in no way to be expected. It

25 is noteworthy in this context that for the dediolization according to the invention via the

The present invention is preferably concerned with the method of selective dehydration as well

production of synthetic monoalcohols. They found certain catalysts to be particularly useful

applies in particular to a method for cleaning such as have shown. So these are in particular catalytic

cher monoalcohols by removing secondary _{gates of} the elements aluminum, zirconium and titanium,

products which, during their synthesis, differ to a small extent both in the form of their oxides, hydroxides and

Form scope. Alkoxides can be applied. That too

Synthetic primary monoalcohols with more than aluminum oxide, which is known to be a particularly

4 carbon atoms have recently become a good dehydration catalyst for alcohols

Technology gained increased importance. They serve as ₃₅ 's, likewise such a selective dehydration too

Starting materials for the production of various er-

chemical industry products. The production is surprising. Rather, it was to be expected that the

of such primary monoalcohols, the mono-

realized in this way. In addition to the known alcohols are attacked.

drive, such as B. the oxo synthesis, has _{recently 40} Characterized that after the invention, for example, the process according to Ziegler diolization, the unsätan formed from the diols gained importance, which, starting from saturated compounds to straight-chain alcohols, ethylene using aluminum triethyl, are hydrogenated can, the invention offers moreover leads to straight-chain primary monoalcohols. in addition, the special advantage that from the original

These synthetically produced alcohols contain, 45 borrowed undesirable by-products which can ultimately be obtained in desired substances due to the mechanisms of the syntheses,
A small amount of by-products of various kinds. The deviolization according to the invention can influence the further processing in an undesirable manner, probably from synthetic monoalcohol mixtures. Primary monoalcohols produced in the synthetic series as well as from sections of uniform chains are short in length. In any case, it is found that practically from amounts, inter alia, carbonyl compounds and finally the diols are attacked and the olefinic components are present. Mono alcohols do not participate in the reaction.

For the elimination of the carbonyl compounds For the claimed removal of the diols you can and for the olefinic components, all processes known from the art for liquid-time have been around for a long time known procedures. So z. B. these ver 55 phase reactions can be used. So can the bindings by hydrogenation in the presence of suitable inventive diol removal, for example in one Hydrogenation catalysts easily removed discontinuous process carried out in the manner will. be that the Al-

It has now been found that among the alcohol in the presence of the catalyst in the form of a

cleaning that is treated in the synthetic monoalcohol 60 suspension over a certain period of time and

are included, the diols with secondary OH groups then the purified alcohol by FiI-

Disrupts the further processing of the monotra- tion from the contact,

cause alcohol. The invention therefore relates to a If you want to work continuously, you can

Process for the purification of synthetically produced particularly advantageous also proceed so that one the

Monoalcohols, in which the diols contained in them 65 are firmly arranged in a reactor and the catalyst

with secondary OH groups in monoalcohols over alcohol either in the trickle process over this

be performed, in which the diols leads in the liquid phase contact layer or else in a

subjected to catalytic dehydration and rising liquid column from below with contact