WO2009124979A1

WO2009124979A1 - C17 alcohol mixture

Info

Publication number: WO2009124979A1
Application number: PCT/EP2009/054252
Authority: WO
Inventors: Jens Rudolph; Armin Ulonska; Rainer Papp; Rocco Paciello; Boris Breitscheidel; Klaus Faller
Original assignee: Basf Se
Priority date: 2008-04-10
Filing date: 2009-04-08
Publication date: 2009-10-15

Abstract

The invention relates to a C17 alcohol mixture, a method for the production thereof, and the use thereof.

Description

Ci7-alcohol mixture

description

The present invention relates to a Ci7 alcohol mixture, a process for its preparation and its use.

The best possible use of the raw material oil is desirable due to dwindling resources and high crude oil prices. In the process, it is becoming increasingly important to further avoid the occurrence of by-products within the existing value-added chains or to make unavoidable by-products economically viable. In particular, it should be avoided to introduce these by-products back to the beginning of the finishing chain.

Hydrocarbon mixtures containing short-chain olefins, eg. B. containing 2 to 6 carbon atoms are available on a large scale. So falls z. For example, in the work-up of petroleum by steam cracking or fluidized catalyst cracking (FCC), a hydrocarbon mixture having a high total olefin content, referred to as C4 cut, which is essentially four-carbon olefins. Such C4 cuts, d. H. Mixtures of isomeric butenes and butanes, are suitable, optionally after a previous separation of the isobutene and hydrogenation of the butadiene contained, very well for the preparation of oligomers, in particular of octenes and dodecenes. However, higher oligomers with a carbon atom number of 16 or more are always obtained which, at present, can not yet be used optimally economically and which are therefore recycled for further use, for example, into the steam cracker. Thus, there is a need for a process that opens up new uses for previously unexploited higher olefin mixtures.

Of great importance are the substantially linear oligomer mixtures obtainable from olefin mixtures with predominantly linear starting olefins. They are suitable for. B. as a diesel fuel component and as intermediates for the preparation of functionalized, predominantly linear hydrocarbons. Thus, by hydroformylation and subsequent hydrogenation of the olefin oligomers, the corresponding alcohols are used, inter alia, as starting materials for detergents and as plasticizers. Up to now olefins with a not too high degree of branching have been used for use as plasticizer alcohols. The degree of branching is described for example by the ISO index, which indicates the average number of branches of the respective olefin fraction. To wear z. For example, for a Cs fraction, the n-octenes with 0, methyl heptane with 1 and di methylhexene with 2 to the iso index of the fraction at. The lower the iso-index, the greater the linearity of the molecules in each fraction. US 5,306,848 describes a process for the preparation of oxo alcohols. As a suitable Olefinausgangsgemisch C2-Ci7 monoolefins are mentioned.

DE 197 40 672 describes the preparation of aldehydes by hydroformylation of olefins, 1-hexadecene being mentioned within the scope of an extensive list.

EP 0 987 241 A1 describes a process for the selective hydrogenation of reaction mixtures from the hydroformylation of Cs-C24 olefins by means of hydrogen over solid catalysts which contain copper, nickel and chromium as active components.

EP 0 987 242 A1 describes a process for preparing higher oxo alcohols from mixtures of isomeric olefins having 5 to 24 carbon atoms by hydroformylation in the presence of a catalyst at elevated temperature and under elevated pressure, wherein the hydroformylation is carried out in one stage, the conversion of Limiting olefins to 40 to 90% for one run, the reaction mixture is selectively hydrogenated, the hydrogenation mixture is separated by distillation and the olefin fraction is recycled to the hydroformylation.

EP 0 407 687 describes a hydroformylation process in which, inter alia, the dimers, trimers or tetramers of propene, n-butene or isobutene can be used as olefin feed. However, preferred olefin feeds are monounsaturated fatty acids and derivatives thereof. The reaction of an oligomerization product enriched by distillation in the form of C 16 -olefins is not described.

US 4,584,411 describes a process for the hydroformylation of an olefin oligomerization product. The oligomerization product is obtained by liquid-phase oligomerization of propene and / or butene on a nickel-alkylaluminum halide catalyst. Specifically, only C6-Ci2-olefins are used for hydroformylation. The hydroformylation catalyst is designed to rapidly convert an oligomerization product with olefin oligomers of different carbon atom number into alcohols.

DE 102 27 995 A1 describes a process for preparing aliphatic alcohols having 7 to 17 carbon atoms by one or more reaction stages, each comprising the steps

a) cobalt-catalyzed hydroformylation of olefins having 6 to 16 carbon atoms, b) treatment of the hydroformylation mixture with oxygen-containing gases in the presence of acidic, aqueous cobalt (II) salt solutions,

c) separation of the mixture from b) an aqueous phase containing cobalt salts and an organic phase containing the aliphatic aldehydes,

d) hydrogenation of the aldehyde-containing organic phase, wherein

e) extracting the organic phase from c) with a liquid containing water.

The Olefineinsatzgemische are extremely broadly defined, details of branching degrees are not found.

DE 102 41 266 A1 describes a process for the preparation of aliphatic alcohols having 7 to 17 carbon atoms by one or more reaction stages, each comprising the steps

a) cobalt-catalyzed hydroformylation of olefins having 6 to 16 carbon atoms,

b) oxidative decomposition of the active cobalt catalyst in the hydroformylation discharge by reaction with oxygen-containing gases,

c) separation of the mixture from b) into an aqueous phase containing cobalt salt and an organic phase containing the aliphatic aldehydes,

d) distillative separation of the organic phase into a low-boiling fraction comprising unreacted olefins and an aldehyde-containing bottoms fraction,

e) hydrogenation of the aldehyde-containing bottoms fraction,

wherein all process steps are carried out in the presence of water.

The definition of the olefin feed mixtures corresponds to that of DE 102 27 995 A1.

WO 95/14647 describes a process for the oligomerization of unbranched C 2 -C 6 -olefins over a fixed bed catalyst at elevated pressure and elevated temperature, using a catalyst which contains 10 to 70% by weight of nickel oxide as the essential active ingredient. 5 to 30 wt .-% titanium dioxide and / or zirconium dioxide, 0 to 20 wt .-% alumina and the balance contains silicon oxide. DE 199 15 357 A1 describes a process for the oligomerization of C 2 -C 8 -olefins on a nickel-containing heterogeneous catalyst, comprising:

a) a catalyst pretreatment phase in which the catalyst is contacted with a first hydrocarbon mixture having an olefin content of less than 50% by weight and a content of diolefins and alkynes of less than 0.1% by weight, and

b) an operating phase in which a stream of a second hydrocarbon mixture containing from 50 to 100% by weight of C2 to C5 olefins and a

Content of diolefins and alkynes of less than 10 ppm by weight, is brought into contact with the catalyst.

WO 01/37989 describes a process for preparing an oligomerization catalyst for olefins having 2 to 6 carbon atoms, in which aluminum oxide is charged with a nickel compound and a sulfur compound.

In the last three documents, it is generally stated in the introductory part of the description that octenes and dodecenes can be used after hydroformylation and hydrogenation to give alcohols for the preparation of plasticizers or surfactants.

US 2003/0225307 describes a process for the preparation of olefin dimers and oligomers and their further reaction, inter alia, by hydroformylation. The resulting olefin products should be branched as low as possible.

WO 2005/037752 describes a process for the preparation of aliphatic alcohols, in which a first hydrocarbon stream containing olefins and paraffins, for. From Fischer-Tropsch synthesis, dehydrogenation and isomerization to give a second hydrocarbon stream containing branched olefins and subjecting the second hydrocarbon stream to hydroformylation and hydrogenation to give a mixture of aliphatic alcohols which are at least partially branched. The olefins obtained by dehydrogenation and isomerization have a mean degree of branching of 0.7 to 2.5.

WO 98/23566 describes a composition of branched primary alcohols having 8 to 36 carbon atoms and a mean degree of branching per molecule of 0.7 to 3.0, which are methyl and ethyl branches. The preparation takes place via skeletal isomerization of an olefin starting mixture and subsequent hydroformylation. Example 1 of this document describes the preparation of a mixture of primary C 17 -alcohols by isomerization of a linear C 16 -olefin feed to a Pd-containing H-ferrierite as catalyst, hydroformylation a cobalt-phosphine catalyst and subsequent separation by distillation. The mean degree of branching of the obtained Ci7-alcohol is given as 1, 6.

It has now surprisingly been found that can be prepared from the product of the transition metal-catalyzed oligomerization of olefins having 2 to 6 carbon atoms, a Ci7 alcohol mixture with particularly advantageous performance properties. It is crucial that first a Ci6-olefin mixture is isolated by distillation from the product of the olefin oligomerization and only then this Ci6-olefin mixture is subjected to a hydroformylation. Thus, it is possible to provide a more highly branched C 17 -alcohol mixture having particularly advantageous performance properties. This is particularly suitable as a detergent surfactant or for the production of detergent surfactants, for the preparation of lubricants, for the production of plasticizer esters, for the preparation of esters of ethylenically unsaturated mono- and dicarboxylic acids, as a component of carrier oils for fuel additives, as reactive diluents for epoxy resins and as a solvent for Cosmetics.

A first object of the invention is therefore a process for the preparation of a Ci7-alcohol mixture in which

a) providing a hydrocarbon feedstock containing at least one olefin having 2 to 6 carbon atoms,

b) subjecting the hydrocarbon feedstock to oligomerization on a transition metal-containing catalyst,

c) subjecting the oligomerization product obtained in step b) to a distillative separation to give an olefin stream enriched in C 16 -olefins,

d) the Ciβ olefins enriched olefin stream obtained in step c)

Hydroformylation by reaction with carbon monoxide and hydrogen in the presence of a cobalt hydroformylation and then subjected to hydrogenation.

Step a)

Suitable olefin feedstocks for step a) are in principle all compounds which contain 2 to 6 carbon atoms and at least one ethylenically unsaturated double bond.

Preferably, in step a) a technically available, olefin-containing hydrocarbon mixture is used. Preferred industrially available olefin mixtures result from hydrocarbon cracking in petroleum processing, for example by cracking, such as fluid catalytic cracking (FCC), thermocracking or hydrocracking with subsequent dehydrogenation. A preferred technical olefin mixture is the C4 cut. C4 cuts are available, for example, by fluid catalytic cracking or steam cracking of gas oil or by steam cracking of naphtha. Depending on the composition of the C4 cut, a distinction is made between the total C4 cut (crude C4 cut), the so-called raffinate I obtained after the separation of 1,3-butadiene and the raffinate II obtained after the isobutene separation technical olefin mixture is the Cs cut available in naphtha cleavage. Suitable olefin-containing hydrocarbon mixtures having 4 to 6 carbon atoms for use in step a) can furthermore be obtained by catalytic dehydrogenation of suitable industrially available paraffin mixtures. For example, it is possible to produce C4-olefin mixtures from liquid gases (liquified petro- leum gas, LPG) and natural gas liquids (NGL). The latter, in addition to the LPG fraction, additionally comprise relatively large amounts of relatively high molecular weight hydrocarbons (light naphtha) and are thus also suitable for the preparation of Cs and Cβ-olefin mixtures. The preparation of olefin-containing hydrocarbon mixtures containing monoolefins having 4 to 6 carbon atoms from LPG or NGL streams is possible by customary methods known to the person skilled in the art, which as a rule also comprise one or more work-up steps in addition to the dehydrogenation. These include, for example, the separation of at least part of the saturated hydrocarbons contained in the aforementioned olefin feed mixtures. These can, for example, be used again for the production of olefin feedstocks by cracking and / or dehydrogenation. However, the olefins used in step a) may also contain a proportion of saturated hydrocarbons which are inert to the oligomerization conditions. The proportion of these saturated components is generally at most 60% by weight, preferably at most 40% by weight, particularly preferably at most 20% by weight, based on the total amount of olefins and saturated hydrocarbons contained in the hydrocarbon feedstock.

Preferably, in step a) is provided a hydrocarbon mixture comprising 20 to 100% by weight of C ₄ olefins, 0 to 80% by weight of C ₅ olefins, 0 to 60% by weight of C ₆ olefins and 0 to 10 Wt .-% of the aforementioned olefins different olefins, each based on the Gesamtolefinehalt containing.

Preferably, in step a), a hydrocarbon mixture is provided which has a content of linear monoolefins of at least 80% by weight, particularly preferably at least 90% by weight and in particular at least 95% by weight, based on the total olefin content. The linear monoolefins are selected under 1-butene, 2-butene, 1-pentene, 2-pentene, 1-hexene, 2-hexene, 3-hexene, and mixtures thereof. To set the desired degree of branching of the isoalkane mixture, it may be advantageous if the hydrocarbon mixture used in step a) up to 20 wt .-%, preferably up to 5 wt .-%, in particular up to 3 wt .-% branched olefins , based on the Gesamtolefinehalt contains.

Particularly preferably, a C4-hydrocarbon mixture is provided in step a).

The butene content, based on 1-butene, 2-butene and isobutene, of the C 4 -hydrocarbon mixture provided in step a) is preferably 10 to 100% by weight, particularly preferably 50 to 99% by weight, and in particular 70 to 95% by weight, based on the total olefin content. Preferably, the ratio of 1-butene to 2-butene is in a range from 20: 1 to 1: 2, in particular from about 10: 1 to 1: 1. Preferably, the C4-hydrocarbon mixture used in step a) contains less than 5% by weight .-%, in particular less than 3 wt .-% isobutene.

The provision of the olefin-containing hydrocarbons in step a) may comprise a separation of branched olefins. Suitable are customary separation processes known from the prior art which are based on different physical properties of linear and branched olefins or on different reactivities which permit selective reactions. For example, isobutene can be separated from C4 olefin mixtures, such as raffinate I, by one of the following methods:

- molecular sieve separation,

fractional distillation,

reversible hydration to tert-butanol,

acid-catalyzed alcohol addition to a tertiary ether, e.g. B. methanol addition to methyl tert-butyl ether (MTBE),

irreversible catalyzed oligomerization to di- and tri-isobutene,

irreversible polymerization to polyisobutene,

Such methods are described in K. Weissermel, H.-J. Arpe, Industrial Organic Chemistry, 4th edition, pages 76-81, VCH Verlagsgesellschaft Weinheim, 1994, which is incorporated herein by reference.

Preferably, a raffinate II is provided in step a). A raffinate II suitable for use in the process according to the invention has, for example, the following composition:

0.5 to 5% by weight of isobutane, 5 to 20% by weight of n-butane, 20 to 40% by weight of trans-2-butene, 10 to 20% by weight of cis-2-butene, 25 to 55% by weight of 1-butene, 0.5 to 5% by weight of isobutene

as well as trace gases, such as 1, 3-butadiene, propene, propane, cyclopropane, propadiene, methylcyclopropane, vinyl acetylene, pentenes, pentanes, etc. in the range of not more than 1 wt .-%.

A suitable raffinate II has the following typical composition:

i-butane: 3% by weight of n-butane: 15% by weight of i-butene: 2% by weight

Butene-1: 30% by weight

Butene-2-trans: 32% by weight

Butene-2-cis: 18% by weight

If diolefins or alkynes are present in the olefin-rich hydrocarbon mixture, they may be removed from the same prior to oligomerization to preferably less than 100 ppm. They are preferably by selective hydrogenation, for. B. according to EP-81 041 and DE 15 68 542, more preferably by selective hydrogenation to a residual content of less than 50 ppm.

Furthermore, oxygen-containing compounds, such as alcohols, aldehydes, ketones or ethers, are expediently removed from the olefin-rich hydrocarbon mixture. For this purpose, the olefin-rich hydrocarbon mixture with advantage over an adsorbent such. As a molecular sieve, in particular one with a pore diameter of> 4 Ä to 5 Ä, are passed. The concentration of oxygen-containing, sulfur-containing, nitrogen-containing and halogen-containing compounds in the olefin-rich hydrocarbon mixture is preferably less than 1 ppm by weight, in particular less than 0.5 ppm by weight.

Step b) In the context of the present invention, the term "oligomers" includes dimers, trimers, tetramers, pentamers and higher products from the synthesis reaction of the olefins used. The oligomers are themselves olefinically unsaturated. By suitable choice of the hydrocarbon feedstock used for the oligomerization and of the oligomerization catalyst, as described below, an oligomerization product can be obtained which contains C 16 -olefins which can be advantageously further processed to form the C 17 -alcohol mixture according to the invention.

For the oligomerization in step b) it is possible to use a reaction system which comprises one or more identical or different reactors. In the simplest case, a single reactor is used for the oligomerization in step b). However, several reactors may be used, each having the same or different mixing characteristics. The individual reactors may, if desired, be subdivided one or more times by means of internals. Form two or more reactors, the reaction system, they can be interconnected with each other, for. B. parallel or in series. In a suitable embodiment z. B. a reaction system is used, which consists of two series-connected reactors.

Suitable pressure-resistant reaction apparatuses for the oligomerization are known to the person skilled in the art. These include the commonly used reactors for gas-solid and gas-liquid reactions, such. B. tubular reactors, stirred tank, gas circulation reactors, bubble columns, etc., which may optionally be subdivided by internals. Preferably, tube bundle reactors or shaft furnaces are used. If a heterogeneous catalyst is used for the oligomerization, this can be arranged in a single or in a plurality of fixed catalyst beds. It is possible to use different catalysts in different reaction zones. However, preference is given to using the same catalyst in all reaction zones.

The temperature in the oligomerization reaction is generally in a range of about 20 to 280 ⁰ C, preferably from 25 to 200 ⁰ C, in particular from 30 to 140 ⁰ C. The pressure in the oligomerization is generally in a range of about 1 to 300 bar, preferably from 5 to 100 bar and in particular from 20 to 70 bar. If the reaction system comprises more than one reactor, these may have the same or different temperatures and the same or different pressures. Thus, for example, in the second reactor of a reactor cascade, a higher temperature and / or a higher pressure than in the first reactor can be set, for. B. to achieve the fullest possible sales.

In a specific embodiment, the temperature and pressure values used for the oligomerization are selected such that the olefin-containing feedstock is liquid or in the supercritical state. The reaction in step b) is preferably carried out adiabatically. This term is understood in the context of the present invention in the technical and not in the physicochemical sense. Thus, the oligomerization reaction is usually exothermic, so that the reaction mixture undergoes an increase in temperature when flowing through the reaction system, for example a catalyst bed. Adiabatic reaction is understood to mean a procedure in which the amount of heat liberated in an exothermic reaction is taken up by the reaction mixture in the reactor and no cooling by cooling devices is used. Thus, the heat of reaction with the reaction mixture is discharged from the reactor, except for a residual portion, which is released by natural heat conduction and heat radiation from the reactor to the environment.

For the oligomerization in step b), a transition metal-containing catalyst is used. These are preferably heterogeneous catalysts. Preferred catalysts, for the reaction in step a), which are known to bring about low oligomer branching, are generally known to the person skilled in the art. These include those described in Catalysis Today, 6, 329 (1990), in particular pages 336-338, as well as those described in DE-A-43 39 713 (= WO-A 95/14647) and DE-A-199 57 173 Catalysts, which are hereby incorporated by reference. A suitable oligomerization process in which the feed stream used for the oligomerization is divided and fed to at least two reaction zones operated at different temperatures is described in EP-A-1 457 475, to which reference is also made.

Preference is given to using an oligomerization catalyst which contains nickel. In this case, preference is given to heterogeneous catalysts which contain nickel oxide. The heterogeneous nickel-containing catalysts used can have different structures. In principle, unsupported catalysts and supported catalysts are suitable. The latter are preferred. The support materials may, for. Silicic acid, alumina, aluminosilicates, layered aluminosilicates and zeolites such as mordenite, faujasite, zeolite X, zeolite-Y and ZSM-5, zirconia treated with acids, or sulfated titania. Particularly suitable are precipitation catalysts obtained by mixing aqueous solutions of nickel salts and silicates, eg. Sodium silicate with nickel nitrate, and optionally aluminum salts such as aluminum nitrate, and calcination. Furthermore, catalysts can be used which are obtained by incorporation of Ni ²⁺ ions by ion exchange in natural or synthetic phyllosilicates, such as montmorillonites. Suitable catalysts may also be obtained by impregnating silica, alumina or aluminosilicates with aqueous solutions of soluble nickel salts, such as nickel nitrate, nickel sulfate or nickel chloride, followed by calcination. Nickel oxide-containing catalysts are preferred. Particular preference is given to catalysts which consist essentially of NiO, SiO 2, UO 2 and / or ZrO 2 and, if appropriate, Al 2 O 3. Most preferred is a catalyst containing as essential active ingredients 10 to 70% by weight of nickel oxide, 5 to 30% by weight of titanium dioxide and / or zirconium dioxide, 0 to 20% by weight of aluminum oxide and the balance silicon dioxide. Such a catalyst is comprises by precipitation of the catalyst composition at pH 5 to 9 by addition of a nickel nitrate aqueous solution to an alkali metal water glass solution containing titanium dioxide and / or zirconium dioxide, filtering, drying and annealing at 350 to 650 ⁰ C available. For the preparation of these catalysts, reference is made in detail to DE 43 39 713. The disclosure of this document and the cited prior art is incorporated herein by reference.

In a further embodiment, the catalyst used in step b) is a nickel catalyst according to DE-A-199 57 173. This is essentially alumina, which has been charged with a nickel compound and a sulfur compound. Preferably, in the final catalyst, a molar ratio of sulfur to nickel is in the range of 0.25: 1 to 0.38: 1.

The catalyst is preferably in particulate form, for. B. in the form of tablets, for. B. with a diameter of 2 to 6 mm and a height of 3 to 5 mm, rings with z. B. 5 to 7 mm outer diameter, 2 to 5 mm in height and 2 to 3 mm hole diameter, or strands of different lengths of a diameter of z. B. 1, 5 to 5 mm, before. Such forms are obtained in a manner known per se by tabletting or extrusion, usually using a tableting auxiliary such as graphite or stearic acid.

Preferably, in step b) a C4 hydrocarbon mixture is used for oligomerization and an oligomerization product obtained, the 1 to 25 wt .-%, preferably 2 to 20 wt .-%, especially 3 to 15 wt .-% Ciβ-olefins, based on contains the total weight of the oligomerization product.

Step c) Distillation

From the reaction effluent of the oligomerization reaction, a Ciβ-olefin fraction is isolated in one or more separation steps.

The distillative separation of the oligomerization product obtained in step b) to give an olefin stream enriched in C 16 -olefins can be carried out continuously or batchwise (discontinuously).

Suitable distillation apparatuses are the usual apparatus known to the person skilled in the art. These include z. B. distillation columns, such as tray columns, the if desired, may be equipped with internals, valves, side draws, etc., evaporators, such as thin film evaporators, falling film evaporators, wiper blade evaporators, Sambay evaporators, etc., and combinations thereof. The isolation of the C 16 -olefin fraction preferably takes place by fractional distillation.

The distillation itself can be carried out in one or more coupled distillation columns.

The distillation column used or the distillation columns can be realized in a per se known embodiment (see, for example, Sattler, Thermal Separation Process, 2nd edition 1995, Weinheim, page 135ff; Perry's Chemical Engineers Handbook, 7th Edition 1997, New York , Section 13). The distillation columns used may contain separating internals, such as separating trays, for. As perforated plates, bubble trays or valve trays, ordered packs, z. As sheet or tissue packs, or random beds of packing. In the case of using tray columns with downcomers, the well dwell time is preferably at least 5 seconds, more preferably at least 7 seconds. The concrete design and operating data, such as the number of stages required in the column (s) used and the reflux ratio, can be determined by the skilled worker according to known methods.

In a preferred embodiment, a combination of two columns is used for the distillation. In this case, the olefin oligomers having less than 16 carbon atoms (i.e., the Cs and C 12 oligomers when using a C4 hydrocarbon mixture) are taken overhead the first column. The olefin stream enriched in C 16 -olefins is obtained as the top product of the second column. Olefin oligomers having more than 16 carbon atoms (i.e., C20, C24, and higher oligomers when using a C4 hydrocarbon mixture) accumulate as the bottom product of the second column.

As evaporators and capacitors are also known per se types of apparatus. As evaporator, a conventional heatable vessel or an evaporator with forced circulation, for example a falling film evaporator, can be used. If two distillation columns are used for the distillation, they may be provided with identical or different evaporators and condensers.

Preferably at the bottom temperatures occurring during the distillation most 300 ⁰ C, particularly preferably at most 250 ⁰ C. In order to maintain these maximum temperatures, the distillation can be carried out, if desired, under a suitable vacuum.

Preferably, in step c), an olefin stream enriched in C 16 -olefins is isolated which has a content of 16-carbon olefins of at least 95% by weight, particularly preferably at least 98 wt .-%, in particular at least 99 wt .-%, based on the total weight of the Ciβ-olefins enriched olefin stream having. Specifically, in step c), an olefin stream enriched in Ciβ-olefins is isolated which consists essentially (ie, more than 99.5% by weight) of olefins having 16 carbon atoms.

Step d) Hydroformylation

To prepare the alcohol mixture according to the invention, the olefin stream enriched in C 16 -olefins is hydroformylated and then hydrogenated to give C 18 -alcohols. The preparation of the alcohol mixture can be carried out in one stage or in two separate reaction steps.

A review of hydroformylation processes and suitable catalysts can be found in Beller et al., Journal of Molecular Catalysis A 104 (1995), pages 17-85.

It is critical to the present invention that the hydroformylation be carried out in the presence of a cobalt hydroformylation catalyst.

The amount of the hydroformylation catalyst is generally 0.001 to

0.5% by weight, calculated as cobalt metal, based on the amount of olefins to be hydroformylated.

The reaction temperature is generally in the range of about 100 to 250 ^° C., preferably 150 to 210 ^° C.

The reaction can be carried out at an elevated pressure of about 10 to 650 bar, preferably 25 to 350 bar.

In a suitable embodiment, the hydroformylation is carried out in the presence of water; However, it can also be carried out in the absence of water.

Carbon monoxide and hydrogen are usually used in the form of a mixture, the so-called synthesis gas. The composition of the synthesis gas used can vary within a wide range. The molar ratio of carbon monoxide and hydrogen is usually about 2.5: 1 to 1: 2.5. A preferred ratio is about 1: 1.

The hydroformylation-active cobalt catalyst is HCo (CO) ₄ . The catalyst may be outside the hydroformylation reactor, e.g. B. from a cobalt (II) salt in the presence of synthesis gas, preformed and introduced together with the Ciβ-olefins and the synthesis gas in the hydroformylation reactor. Alternatively, the image tion of the catalytically active species from catalyst precursors only under the hydroformylation conditions, ie in the reaction zone. Suitable catalyst precursors are cobalt (II) salts, such as cobalt (II) carboxylates, e.g. Cobalt (II) formate, cobalt (II) acetate and cobalt (II) ethyl hexanoate; and cobalt (II) acetylacetonate or Co ₂ (CO) ₈ .

The cobalt catalyst homogeneously dissolved in the reaction medium can be suitably separated from the hydroformylation product by first treating the reaction effluent of the hydroformylation with oxygen or air in the presence of an acidic aqueous solution. The cobalt catalyst is oxidatively destroyed to form cobalt (II) salts. The cobalt (II) salts are water-soluble and can be separated by extraction with water from the reaction. They can typically be reused to produce a hydroformylation catalyst and recycled to the hydroformylation process.

For continuous implementation of the hydroformylation can be z. For example, (i) intimately contact an aqueous cobalt (II) salt solution with hydrogen and carbon monoxide to form a hydroformylation-active cobalt catalyst; (ii) intimately contacting the cobalt catalyst-containing aqueous phase in a reaction zone with the olefins and hydrogen and carbon monoxide, extracting the cobalt catalyst into the organic phase and hydroformylating the olefins; and (iii) treating the effluent from the reaction zone with oxygen, decomposing the cobalt catalyst to form cobalt (II) salts, extracting the cobalt (II) salts back into the aqueous phase, and separating the phases. The aqueous cobalt (II) salt solution is then recycled to the process. Suitable cobalt (II) salts are, in particular, cobalt (II) acetate, cobalt (II) formate and cobalt (II) ethylhexanoate. Advantageously, the formation of the cobalt catalyst, the extraction of the cobalt catalyst into the organic phase and the hydroformylation of the olefins can be carried out in one step by adding the aqueous cobalt (II) salt solution, the olefins and optionally the organic solvent and hydrogen and carbon monoxide in the reaction zone under hydroformylation conditions, eg. B. by means of a mixing nozzle, intimately brought into contact.

If desired, the crude aldehydes or aldehyde / alcohol mixtures obtained in the hydroformylation can be isolated by conventional methods known to the person skilled in the art and, if appropriate, purified. In general, the product mixture obtained after removal of the hydroformylation catalyst can be used without further workup in the hydrogenation.

hydrogenation For hydrogenation, the reaction mixtures obtained in the hydroformylation are reacted with hydrogen in the presence of a hydrogenation catalyst.

Suitable hydrogenation catalysts are generally transition metals, such as. As Cr, Mo, W, Fe, Rh, Co, Ni, Pd, Pt, Cu, Ru, etc., or mixtures thereof, to increase the activity and stability on carriers such. As activated carbon, alumina, diatomaceous earth, etc. can be applied. To increase the catalytic activity Fe, Co and preferably Ni, also in the form of the Raney catalysts can be used as metal sponge with a very large surface area. Preferably, a Co / Mo catalyst is used for the preparation of the surfactant alcohols according to the invention. The hydrogenation of the oxo-aldehydes takes place, depending on the activity of the catalyst, preferably at elevated temperatures and elevated pressure. Preferably, the hydrogenation temperature is about 80 to 250 ⁰ C. Preferably, the pressure is about 50 to 350 bar.

From the reaction mixture obtained after the hydrogenation, the Ci7 alcohol mixture according to the invention can be obtained in pure form by customary purification processes known to the person skilled in the art, in particular by fractional distillation.

Another object of the invention is a Ci7-alcohol mixture, which can be obtained by

d) subjected to the Ciβ olefins enriched olefin stream obtained in step c) of a hydroformylation by reaction with carbon monoxide and hydrogen in the presence of a cobalt hydroformylation catalyst and then subjected to hydrogenation.

With regard to suitable and preferred embodiments of method steps a) to d), the previous information on these steps is referred to in its entirety.

Another object of the invention is a Ci7-alcohol mixture having a mean degree of branching (iso-index) of 2.8 to 3.7, particularly preferably from 2.9 to 3.6, especially from 3.01 to 3.5, especially from 3.05 to 3.4. A particularly preferred average degree of branching is in the range of about 3.1. The degree of branching is defined as the number of methyl groups in a molecule of the alcohol minus 1. The mean degree of branching is the statistical mean of the branching degrees of the molecules of a sample. The average degree of branching can be determined as follows by 1 H NMR spectroscopy: For this purpose, a sample of the alcohol is first subjected to a derivatization with trichloroacetyl isocyanate (TAI). The alcohols are converted into the carbamic acid esters. The signals of the esterified primary alcohols are at δ = 4.7 to 4.0 ppm, those of the (if present) esterified secondary alcohols at about 5 ppm and water present in the sample reacts with TAI to carbamic acid. All methyl, methylene and methine protons are in the range of 2.4 to 0.4 ppm. The signals <1 ppm are assigned to the methyl groups. From the spectrum thus obtained, the mean degree of branching (iso-index) can be calculated as follows:

Iso Index = ((F (CH ₃ ) / 3) / (F (CH ₂ -OH) / 2)) - 1

where F (CH ₃ ) represents the signal surface corresponding to the methyl protons and F (CH ₂ -OH) represents the signal surface of the methylene protons in the CH ₂ -OH group.

The Ci7 alcohol mixture preferably has a content of alcohols having 17 carbon atoms of at least 95 wt .-%, more preferably at least 98 wt .-%, in particular at least 99 wt .-%, based on the total weight of the Ci7 alcohol mixture on. Specifically, it is a Ci7 alcohol mixture consisting essentially (i.e., greater than 99.5 wt%, especially greater than 99.9 wt%) of alcohols having 17 carbon atoms.

C 17 -alcohol mixtures according to the invention are preferably obtainable by the process defined above.

Another object of the invention is the use of a Ci7 alcohol mixture, as defined above, as a detergent surfactant or for the production of detergent surfactants, for the production of lubricants, for the production of plasticizer esters, for the preparation of esters of ethylenically unsaturated mono- and dicarboxylic acids, as a constituent of carrier oils for fuel additives, as reactive diluents for epoxy resins and as a solvent for cosmetics.

In principle, surfactants of the general formula R ¹ -X are suitable for use as detergent surfactants, where R ¹ is an aliphatic alkyl radical derived from a C 17 -alcohol mixture according to the invention

X is a hydrophilic group which is preferably selected from the group of sulfonate groups, polyoxyalkylene groups, anionically modified polyoxyalkylene groups and pen, glucoside groups, amine oxide groups, etc. Such surfactants per se are not the subject of this application.

Lubricants based on the C 17 -alcohol mixtures according to the invention are suitable, for example, as motor oils and gear oils. As lubricants preferably esters of the general formula (RO-C (= O)) _y -X- (C (= O) OR) are used, wherein X is a straight-chain or branched alkylene radical or arylene radical and the radicals R are aliphatic alkyl radicals of the formula C17H35-, which are derived from the Ci7 alcohol mixture according to the invention by formal cleavage of the OH groups.

Preferably, the radical X is an arylene radical of the formulas

Further preferably, the radical X is a radical of the formula (CR ¹ R ² ^ _n in which

R ¹ and R ² independently of one another represent hydrogen or C ¹ -C 5 -alkyl radicals and n has the meanings 2 to 12, eg. For example, for a - (CHb) _n -ReSt.

Such lubricants and their formulation are described in EP 0 264 842, to which reference is made.

Suitable plasticizer esters are obtainable by reacting a dicarboxylic acid with a Ci7 alcohol mixture according to the invention by customary methods known to the person skilled in the art. Suitable dicarboxylic acids are aromatic and aliphatic organic dicarboxylic acids having preferably 3 to 12 carbon atoms. Particularly preferred are such dicarboxylic acids having 6 to 8 carbon atoms as adipic acid and phthalic acid. In place of the dicarboxylic acids, their derivatives, which are generally more reactive in esterification reactions, such as anhydrides, in the case of phthalic acid, for example, phthalic anhydride, or the acid dichlorides may also be used. The preparation of such plasticizer is z. As described in DE-A-102 36 279, which is incorporated herein by reference. The C 17 -alcohol mixtures according to the invention are suitable for the preparation of plasticizers for various plastics, in particular PVC and polyolefins.

The Ci7-alcohol mixtures according to the invention are also suitable for the preparation of esters of ethylenically unsaturated mono- and dicarboxylic acids, the z. B. in the production of polymers by free radical polymerization are used. Suitable ethylenically unsaturated carboxylic acids are, for. For example, acrylic acid, methacrylic acid, ethacrylic acid, maleic acid, itaconic acid, citraconic acid, mesaconic acid, glutaconic acid. re, aconitic acid and fumaric acid. In particular, they are esters of acrylic acid, methacrylic acid and the esters and half esters of maleic acid.

Fuel additives, especially for diesel and gasoline engines, are usually used in the form of so-called additive packages. These usually contain a carrier oil. The carrier oil acts as a carrier for further, usually detergent active, additives. The Ci7-alcohol mixtures according to the invention are advantageously suitable as a carrier oil or as a component of a carrier oil mixture.

Suitable mineral carrier oils for combination with the C 17 -alcohol mixture according to the invention are fractions obtained in petroleum processing, such as bright stock or base oils having viscosities such as, for example, from class SN 500 to 2000; but also aromatic hydrocarbons, paraffinic hydrocarbons and alkoxyalkanols. It is also useful as a "hydrocrack oil" known and obtained in the refining of mineral oil fraction (Vakuumdestillatschnitt with a boiling range of about 360 to 500 ⁰ C, available from high pressure catalytically hydrogenated and isomerized and dewaxed natural mineral oil). Also suitable are mixtures of the abovementioned mineral carrier oils.

Examples of synthetic carrier oils which can be used with the C 17 -alcohol mixture according to the invention are selected from: polyolefins (polyalphaolefins or poly-internalolefins), (poly) esters, (poly) alkoxylates, polyethers, aliphatic polyether amines, alkylphenol-initiated polyethers, alkylphenol-initiated polyetheramines and carboxylic esters of long-chain alkanols ,

Examples of suitable polyolefins are olefin polymers having M _n = 400 to 1800, especially based on polybutene or polyisobutene (hydrogenated or non-hydrogenated).

Examples of suitable polyethers or polyetheramines are preferably compounds containing polyoxy-C 2 -C 4 -alkylene groups, which are prepared by reacting C 2 -C 6 -alkanols, C 6 -C 50 -alkanediols, mono- or di-C 2 -C 30 -alkylamines, C 1 -C 30 -alkylcyclohexanols or Ci-C3o-alkylphenols with 1 to 30 mol of ethylene oxide and / or propylene oxide and / or butylene oxide per hydroxyl group or amino group and, in the case of polyether amines, by subsequent reductive amination with ammonia, monoamines or polyamines are available. Such products are described in particular in EP-A-310 875, EP-A-356 725, EP-A-700 985 and US-A-4,877,416.

Examples of carboxylic acid esters of long-chain alkanols are in particular esters of mono-, di- or tricarboxylic acids with long-chain alkanols or polyols, as described in particular in DE-A-38 38 918. As mono-, di- or tricarboxylic acids, aliphatic or aromatic acids can be used, as ester alcohols or polyols are especially long-chain representatives with, for example, 6 to 24 carbon atoms. Typical representatives of the esters are adipates, phthalates, isophthalates, terephthalates and trimellitates of isooctanol, isononanol, isodecanol and Isotridecanols, such as. For example, di (n- or iso-tridecyl) phthalate.

Further suitable carrier oil systems are described, for example, in DE-A-38 26 608, DE-A-41 42 241, DE-A-43 09 074, EP-A-0 452 328 and EP-A-0 548 617, to which reference is hereby expressly made. Further suitable synthetic carrier oils are also alkoxylated alkylphenols, as described in DE-A-10 102 913.6.

The Ci7-alcohol mixtures according to the invention are suitable in cosmetics especially as a solvent for fragrances. They are characterized by their low odor and the good solubility of a variety of different fragrances in them.

The invention will be further illustrated by the following non-limiting examples:

olefin oligomerization:

In an isothermally operated reactor having a length of about 1.5 m and a diameter of 30 mm, at 20 bar and 80 ^° C., raffinate II of the following compositions was reacted on a heterogeneous catalyst.

i-butane: 3% by weight of n-butane: 15% by weight of i-butene: 2% by weight

Butene-1: 30% by weight

Butene-2-trans: 32% by weight butene-2-cis: 18% by weight

The catalyst used was a material which had been prepared in accordance with DE-A-43 39 713 in the form of tablets (5 mm × 5 mm). The composition in wt .-% of the active components was: 50 wt .-% NiO, 12.5 wt .-% TiO ₂ , 33.5 wt .-% SiO ₂ , 4 wt .-% Al ₂ O ₃ . The throughput was 0.75 kg raffinate ll / (l (Kat) xh). Man worked without recycling of C4 hydrocarbons. The C 4 conversion, based on the butenes contained in the raffinate II, was 52.0% by weight.

The selectivity in wt% was as follows: C ₈ : 76.9; Ci ₂ : 18.4 and Ci ₆₊ : 4.7.

Distillation of the Ci6 + mixture: The crude Ci6 + mixture was distilled in a technical distillation plant consisting of two columns, each with about 15 m packing height (250 m ² / m ³ ). In this case, in the first column (forerunner) still contained low boilers (especially Ci2-olefins) taken over the head. In the second column (main run column), the Ci6 olefin was removed overhead with a purity of> 99%, while the C2o + olefins were separated in the bottom. The two columns were operated with the following parameters:

Feed column main run column

Head temperature 135 ⁰ C 165 ⁰ C

Bottom temperature 180 - 182 ⁰ C 225 - 230 ⁰ C

Pressure (head) 85 mbar 60 mbar

Pressure loss over pack approx. 5 mbar approx. 50 mbar

Infeed 2700 kg / h 2500 kg / h

Head discharge 200 kg / h 1700 kg / h

Return 850 kg / h 3000 kg / h

Sump deduction 2500 kg / h 800 kg / h

hydroformylation:

The hydroformylation unit described in EP 1 204 624 was continuously charged with 2.2 t / h of C 16 -olefin and 0.2 t / h of an aqueous cobalt salt solution. The following conditions were set in the reactor:

Cobalt concentration 0.10 wt%

Temperature 185 ^° C

Pressure (CO / H ₂ approx. 1: 1) 280 bar

The discharge of the hydroformylation was oxidatively entcobaltet as described in EP 1,204,624, and then hydrogenated in the hydrogenation plant described in DE 10 036 172 on the Co / Cu / Mo catalyst described there to the alcohol. The following parameters were set:

Temperature 160 ^° C

Pressure (H ₂₎ 280 bar

The crude alcohol thus obtained was purified in the distillation apparatus described above under the following conditions to pure alcohol.

Feed column main run column

Head temperature 155 ⁰ C 214 ⁰ C

Bottom temperature 222 ⁰ C 235 ⁰ C Pressure (head) 60 mbar 60 mbar

Pressure loss over pack 20 mbar 20 mbar

Infeed 2450 kg / h 2000 kg / h

Head outlet 450 kg / h 1800 kg / h

Return 850 kg / h 900 kg / h

Bottom outlet 2000 kg / h 200 kg / h

Method for determining the iso index of the Ci7 alcohol mixture via ¹ H-NMR:

Approximately 20 mg of Ci7-alcohol mixture are dissolved in 0.4 ml of CDCb and a small amount of TMS is added for frequency referencing. Thereafter, the solution is mixed with 0.2 ml TAI, filled into a 5 mm NMR tube and measured in the NMR spectrometer.

Measurement conditions:

Spectrometer frequency: 400 MHz

Relaxation delay: 10 s

Pulse angle: 30 °

Recorded data points: 64 K

Number of Scans: 64 Transformed Data Points 64 K

Exponential multiplication: 0.2 Hz

After Fourier transformation, automatic phase and baseline correction, a manual integration of the ranges 4.7 to 3.7 ppm (all TAI esterified primary alcohols) and 2.4 to - 0.4 ppm (all methyl, methylene and methine). The zeroth-order integral phases are chosen so that the beginning and end of the Integra I curves are substantially horizontal. The signals <1 ppm are assigned to the methyl groups.

Iso Index: 3.1

Claims

claims

1. A process for the preparation of a Ci7-alcohol mixture in which

2. The method of claim 1, wherein in step a) a C4 hydrocarbon mixture is provided.

3. The method of claim 2, wherein in step a) as a C4 hydrocarbon mixture, a raffinate II is provided.

4. The method according to any one of the preceding claims, wherein the used in step b) oligomerization catalyst contains nickel oxide.

5. The method of claim 4, wherein the catalyst consists essentially of NiO, SiÜ2, TΪO2 and / or ZrÜ2 and optionally Al2O3.

6. The method according to any one of the preceding claims, wherein used in step b) a C4 hydrocarbon mixture for oligomerization and an oligomerization product is obtained, the 1 to 25 wt .-%, preferably 2 to 20 wt .-%, especially 3 to 15 wt .-% Ciβ-olefins, based on the total weight of the oligomerization product.

7. The method according to any one of the preceding claims, wherein in step c) is separated from a Ciβ olefins enriched olefin stream having a content of olefins having 16 carbon atoms of at least 95 wt .-%, particularly preferably at least 98 wt .-%, in particular at least 99 wt .-%, based to the total weight of the Ci6 olefins enriched olefin stream.

8. Ci7-alcohol mixture, obtainable by reacting

9. Ci7-alcohol mixture according to claim 8, having a mean degree of branching (iso-index) of 2.8 to 3.7, preferably from 2.9 to 3.6, in particular from 3.01 to 3.5, especially from 3 , 05 to 3,4.

10. Ci7 alcohol mixture according to any one of claims 8 or 9, having a content of alcohols having 17 carbon atoms of at least 95 wt .-%, more preferably at least 98 wt .-%, in particular at least 99 wt .-%, based on the total weight of the Ci7 alcohol mixture having.

1 1. Ci7 alcohol mixture according to one of claims 8 to 10, which is obtainable by a method as defined in any one of claims 1 to 7, is available.

12. Use of a Ci7 alcohol mixture as defined in any one of claims 8 to 11, as detergent surfactant or for the production of detergent surfactants, for the production of lubricants, for the preparation of plasticizer esters, for the preparation of esters of ethylenically unsaturated mono- and dicarboxylic acids, as Component of carrier oils for fuel additives, as a reactive diluent for epoxy resins and as a solvent for cosmetics.