WO2006077082A1

WO2006077082A1 - Method for sealing rotating shafts

Info

Publication number: WO2006077082A1
Application number: PCT/EP2006/000390
Authority: WO
Inventors: Martin Fiene; Oliver Huttenloch; Steffen OEHLENSCHLÄGER; Karel Klikos; Uwe Vagt
Original assignee: Basf Aktiengesellschaft
Priority date: 2005-01-21
Filing date: 2006-01-18
Publication date: 2006-07-27
Also published as: DE102005003115A1

Abstract

The invention relates to a method for sealing rotating shafts while using slide ring seals, during which a sealing liquid is used that contains an ionic liquid. The invention also relates to the use of ionic liquids as a component of the sealing liquid for slide ring seals in order to seal rotating shafts.

Description

Method for sealing rotating shafts

description

The present invention relates to a method for sealing rotating shafts using mechanical seals and the use of ionic liquids as part of the sealing liquid for mechanical seals for sealing rotating shafts.

Rotating shafts have a very wide range of applications and can be found in many drives for the transmission of rotary motion, for example in vehicles, household appliances, power generation equipment, pumps, process engineering equipment, and aerospace applications. To seal the rotating shafts, in addition to stuffing boxes, which are used in the area of low quality requirements, mechanical seals are used above all with high quality and in particular high tightness requirements. A general overview of mechanical seals can be found for example in the book E. Mayer, "Axial mechanical seals", 7th edition, VDI-Verlag Dusseldorf, 1982, ISBN 3-18- 400500-3, page 1 to 19.

When using machines with higher tightness requirements usually mechanical seals are used with so-called barrier fluids. These serve primarily as additional sealing of the rotating shaft, for example when passing through a housing part, but also for lubricating the mechanical seal and for removing the frictional heat generated there. As barrier liquids usually water or oils are used. Thus, in the "Burgmann Lexicon of mechanical seals" (www.burgmann.de/lexikon/de/lex-art-1940.htm, as of 07.12.2004) and in B. Thier, "Handbook seals" 1st edition, Verlag W.H. Faragallah, Sulzbach / Taunus 1990, page 85 Described water and hydraulic oil as barrier liquid. In the information magazine "face to face", July 2003 issue of the company flowserve are as suitable barrier fluids water, water / glycol mixtures, diesel, light lubricating oil and synthetic high-temperature oil called.

A disadvantage of the use of water or aqueous barrier fluids is, inter alia, their high vapor pressure and associated low boiling point in

Range of 100 ⁰ C + x fle after antifreeze), which limits especially the operating temperature and generally requires a correspondingly strong cooling. Despite cooling, there is a danger of the formation of gas bubbles by a local overheating of the slip rings with the result of dry running between the sliding surfaces and thus a thermal destruction of the mechanical seal. Furthermore, due to the slight leakage of the barrier liquid, which is customary for mechanical seals, small amounts of water are emitted both to the atmosphere side and to the product side. which can cause undesirable side reactions, especially in chemical-engineering applications (eg pumps, stirrers, mixers, compressors, compressors, etc.), depending on the present product system. Furthermore, many gases show a very good solubility in water. This can have a negative effect on the function of the mechanical seal: In order to ensure optimum lubrication of the sliding surfaces within the mechanical seal, barrier fluids are subjected to a barrier pressure which is higher than the pressure to be sealed. This is usually done with air or nitrogen superposition within the barrier pressure vessel. If these dissolved gases pass through circulation with the barrier fluid to the sliding surfaces, even at low local overheating gas bubbles can form with the consequences already described above.

Furthermore, very many gases show a very good solubility in water, which means that, for example, in chemical-process engineering applications in which the mechanical seal seals against gases that are soluble in water in a gas phase (eg in compressors, compressors, etc.). ), the gas dissolves over time in the barrier liquid and then even at low local overheating gas bubbles can form with the consequences already described above.

A disadvantage of the use of oils is, inter alia, their tendency to coke under temperature load. In order to minimize coking various complex measures are required, such as the use of a correspondingly strong cooling, the use of particularly complex to produce and expensive synthetic high temperature oils and / or the frequent change of oil. If a coking is not recognized in good time, it may lead to serious damage due to deposits in the sealing system, resulting in interruption of operation with subsequent repairs or cleaning work. Even with the use of oils, their customary slight escape along the rotating shaft, in particular in chemical-process applications, may also lead to undesired side reactions, depending on the present product system. In addition, many gases have a very good solubility in oils, so that here also the problems described in the previous paragraph can occur.

Object of the present invention was to find a method for sealing rotating shafts, which does not have the disadvantages of the prior art, even at high temperatures still works well and reliably, in chemical-engineering applications no or only a minor and thus tolerable Interaction with a variety of different product systems with it and yet has only a slight leakage. Accordingly, a method has been found for sealing rotating shafts using mechanical seals, which is characterized in that one uses a barrier liquid containing an ionic liquid.

Furthermore, the use of ionic liquids has been found as part of the sealing fluid for mechanical seals for sealing rotating waves.

Ionic liquids in the sense of the present invention

(A) Salts of the general formula (I)

[A] _n ⁺ [Y] "^" (I) ₁

in which n is 1, 2, 3 or 4, [A] ^{+ is} a quaternary ammonium cation, an oxonium cation, a sulfonium cation or a phosphonium cation, and [Y] "^'is a one, two or more -, tri- or tetravalent anion stands;

(B) mixed salts of the general formulas (II)

[A ¹ ] ⁺ [A ² ] ⁺ [Y] ^{2 "} (Ha);

[A ¹ ] ⁺ [A ² ] ⁺ [A ³ ] ⁺ [Y] ³ - (IIb); or [A ¹ ] ⁺ [A ² ] ⁺ [A ³ ] ⁺ [A ⁴ ] ⁺ [Y] ⁴ - (IIc),

where [A ^1] ⁺ [A ² J ^+, [A ³ J ⁺ and [A are ^4] ⁺ are independently selected from the for [A] ^+-called groups and [Y] ^"" under (A) has meaning or

(C) mixed salts of the general formulas (III)

[A ¹ J ⁺ [A ² J ⁺ [A ³ J ⁺ [MT [Y] ^{4 "} (HIa);

[A ¹ J ⁺ [A ² J ⁺ [M ¹ J ⁺ [M ² J ⁺ [Y] ⁴ - (HIb);

[A ¹ J ⁺ [M ¹ J ⁺ [M ² J ⁺ [M ³ J ⁺ [Y] ⁴ - (Never);

[A ¹ J ⁺ [A ² J ⁺ [M ¹ J ⁺ [Y] ³ - (HId);

[A ¹ J ⁺ [M ¹ J ⁺ [M ² J ⁺ [Y] ³ - (Never);

[A ¹ ] ⁺ [M ¹ ] ⁺ [Y] ² - (Ulf);

[A ¹ J ⁺ [A ² J ⁺ [M ⁴ J ²⁺ [Y] ^{4 "} (mg);

[A ¹ J ⁺ [M ¹ J ⁺ [M ⁴ J ²⁺ [YJ ⁴ - (HIh);

[A ¹ J ⁺ [M ⁵ J ³⁺ [Y] ⁴ - (Uli); or

[A ¹ J ⁺ [M ⁴ J ²⁺ [Y Y ^{3 "} (IHj)

where [A ¹ J ⁺ . [A ² J ⁺ and [A ³ J ^{+ are} independently selected from the groups specified for [A] ⁺ , [Y] "^'has the meaning given under (A), and [M ¹ ] ⁺ _> [M ² ] ⁺ , [M ³ ] ⁺ monovalent metal cations, [M ⁴ ] ^{z +} divalent metal cations and [M ⁵ J ³⁺ trivalent metal cations,

which have a melting point of <15O ⁰ C.

Are as used in the novel method of ionic liquids, preferably a melting point of -50 ⁰ C (223 K) to <150 ⁰ C (423 K) and most preferably from -20 ° C (253 K) to 12O ⁰ C (393 K).

The cation [A] ⁺ is preferably a quaternary ammonium cation, which generally contains 1 to 5, preferably 1 to 3 and particularly preferably 1 to 2 nitrogen atoms. Suitable cations are, for example, the cations of the general formulas (IVa) to (IVw)

(IVd) (IVe) (IVf)

(IVg) (IVg ¹ ) (IVh)

(IVi) (IVj) (IVj ')

(IVk) (IVk ¹ ) (IVI)

(IVm) (IVm ¹ ) (IVn)

(IVn ¹ )

(IVo ')

(IVp) (IVq) (IVq ¹ )

(IVq ") (IVr) (IVr ')

(IVr ") (IVs) (IVt)

(IVu) (IVv) (IVw)

and oligomers containing these structures. Another suitable cation is also a phosphonium cation of the general formula (Iz)

(IVx)

and oligomers containing this structure.

In the above formulas (IVa) to (IVy)

• the radical R is a carbon-containing organic, saturated or unsaturated, acyclic or cyclic, aliphatic, aromatic or araliphatic, unsubstituted or interrupted by 1 to 5 heteroatoms or functional groups radical having 1 to 20 carbon atoms; and

• the radicals R ¹ to R ⁹ independently of one another are hydrogen, a sulfo group or a carbon-containing organic, saturated or unsaturated, acyclic or cyclic, aliphatic, aromatic or araliphatic, unsubstituted or interrupted by 1 to 5 heteroatoms or functional groups Radical having 1 to 20 carbon atoms, where the radicals R ¹ to R ⁹ , which in the above-mentioned formulas (IV) to a

Carbon atom (and not bound to a heteroatom), in addition, may also be halogen or a functional group; or

two adjacent radicals from the series R ¹ to R ⁹ together also for a divalent, carbon-containing organic, saturated or unsaturated, acyclic or cyclic, aliphatic, aromatic or araliphatic, unsubstituted or interrupted by 1 to 5 heteroatoms or functional groups radical or substituted 1 to 30 carbon atoms.

Suitable hetero atoms in the definition of the radicals R and R ¹ to R ^{9 are in} principle all heteroatoms in question which are capable of formally a -CH ₂ -, a -CH =, a -C≡ or a = C = group to replace. When the carbon-containing group contains heteroatoms, oxygen, nitrogen, sulfur, phosphorus and silicon are preferable. Particular preferred groups are -O-, -S-, -SO-, -SO ₂ -, -NR'-, -N =, -PR'-, -PR ' ₂ and -SiR' ₂ - called, where the radicals R ¹ are the remainder of the carbon-containing radical. The radicals R ¹ to R ⁹ are, in the cases in which these are attached in the abovementioned formulas (IV) to a carbon atom (and not to a heteroatom), also be bound directly via the heteroatom. Suitable functional groups are in principle all functional groups which may be bonded to a carbon atom or a heteroatom. Suitable examples are -OH (hydroxy), = 0 (especially as carbonyl group), -NH ₂ (amino), = NH (imino), -COOH (carboxy), -CONH ₂ (carboxamide), -SO ₃ H (sulfo ) and -CN (cyano). Fractional groups and heteroatoms can also be directly adjacent, so that combinations of several adjacent atoms, such as -O- (ether), -S- (thioether), -COO- (ester), -CONH- (secondary amide) or -CONR ¹ - (tertiary amide) are encompassed, for example di (CrC ₄ alkyl) amino, C ₁ -C ₄ - alkyloxycarbonyl or C _r C ₄ alkyloxy.

Halogens are fluorine, chlorine, bromine and iodine.

The radical R preferably stands for

• straight-chain or branched, unsubstituted or monosubstituted to hydroxyl, halogen, phenyl, cyano, C ₁ - to C ₆ -alkoxycarbonyl and / or sulfonic acid substituted C ₁ - to C ₁₈ -alkyl having a total of 1 to 20 carbon atoms, such as for example, methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl-1-propyl (isobutyl), 2-methyl-2-propyl (tert-butyl), 1-pentyl, 2-pentyl, 3-pentyl,

2-methyl-butyl, 3-methyl-1-butyl, 2-methyl-2-butyl, 3-methyl-2-butyl, 2,2-dimethyl-propyl, 1-hexyl, 2-hexyl, 3 Hexyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl-2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2-methyl-3-pentyl, 3-methyl-3-pentyl, 2,2-dimethyl-1-butyl, 2,3-dimethyl-1-butyl, 3,3-dimethyl-1-butyl, 2-ethyl 1-butyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl,

1-heptyl, 1-octyl, 1-nonyl, 1-decyl, 1-undecyl, 1-dodecyl, 1-tetradecyl, 1-hexadecyl, 1-octadecyl, 2-hydroxyethyl, benzyl, 3-phenylpropyl, 2- Cyanoethyl, 2- (methoxycarbonyl) ethyl, 2- (ethoxycarbonyl) ethyl, 2- (n-butoxycarbonyl) ethyl, trifluoromethyl, difluoromethyl, fluoromethyl, pentafluoroethyl, heptafluoropropyl, heptafluoroisopropyl, nonafluorobutyl, nonafluoroisobutyl, undecylfluoropentyl, nonyl decylfluoroisopentyl, 6-hydroxyhexyl and propylsulfonic acid;

• Glycols, butylene glycols and their oligomers having 1 to 100 units and a hydrogen or a C ₁ - to C ₈ alkyl as an end group, such as R ^A O- (CHR ^B -CH ₂ -O) _n -CHR ^B -CH ₂ - or R ^) - (CH ₂ CH ₂ CH ₂ CH ₂ O) _n -CH ₂ CH ₂ CH ₂ CH ₂ O- where R ^A and R ^{B are} preferably hydrogen, methyl or ethyl and n is preferably 0 to 3, in particular 3 Oxabutyl, 3-oxapentyl, 3,6-dioxaheptyl, 3,6-dioxaoctyl, 3,6,9-trioxadecyl, 3,6,9-trioxa-undecyl, 3,6,9, 12-tetraoxatridecyl and 3,6 , 9,12-tetraoxatetradecyl;

• vinyl; and • N ₁ N-di-C ₁ - to C ₆ -alkyl-amino, such as N, N-dimethylamino and N ₁ N-diethylamino. Particularly preferably, the radical R is unbranched and unsubstituted C ₁ -C -alkyl, for example methyl, ethyl, 1-propyl, 1-butyl, 1-pentyI, 1-hexyl, 1-heptyl, 1-octyl, 1 Decyl, 1-dodecyl, 1-tetradecyl, 1-hexadecyl, 1-octadecyl, especially for methyl, ethyl, 1-ButyI and 1-octyl and CH ₃ O- (CH ₂ CH ₂ O) _n -CH ₂ CH ₂ - and CH ₃ CH ₂ O- (CH ₂ CH ₂ O) _n -CH ₂ CH ₂ - where n is equal to 0 to 3.

The radicals R ¹ to R ⁹ are preferably each independently

• hydrogen; • halogen;

• a functional group;

Optionally C ₁ interrupted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and / or heterocycles and / or interrupted by one or more oxygen and / or sulfur atoms and / or one or more substituted or unsubstituted imino groups - to cis-alkyl;

Optionally substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and / or heterocycles substituted and / or interrupted by one or more oxygen and / or sulfur atoms and / or one or more substituted or unsubstituted imino C ₂ bis Ci ₈ alkenyl; Optionally C ₆ - to C ₁₂ -aryl substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and / or heterocycles;

Optionally substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and / or heterocycles substituted C ₅ - to C- | ₂ -cycloalkyl;

C ₅ - to C ₁₂ -cycloalkenyl optionally substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halo, heteroatoms and / or heterocycles; or

• an optionally substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and / or heterocycles substituted five to six-membered, oxygen, nitrogen and / or sulfur atoms having heterocycle; or

two adjacent radicals together for

• an unsaturated, saturated or aromatic, optionally substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and / or heterocycles and optionally substituted by one or more oxygen and / or sulfur atoms and / or one or more substituted or unsubstituted Imino groups broken ring.

When optionally substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and / or heterocycles C ₁ - to C ₁₈ -alkyl, it is preferably methyl, ethyl, 1-propyl, 2-propyl, 1-butyl , 2-butyl, 2-methyl-1-propyl (isobutyl), 2-methyl-2-propyl (tert-butyl), 1-pentyl, 2-pentyl, 3-pentyl, 2-methyl-1 butyl, 3-methyl-1-butyl, 2-methyl-2-butyl, 3-methyl-2-butyl, 2,2-dimethyl-1-propyl, 1-hexyl, 2-hexyl, 3-hexyl, 2-methyl 1-pentyI, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl-2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2-methyl-3 pentyl, 3-methyl-3-pentyl, 2,2-dimethyl-1-butyl, 2,3-dimethyl-i-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, 2, 3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl, heptyl, octyl, 2-ethylhexyl, 2,4,4-trimethylpentyl, 1,1,3,3-tetramethylbutyl, 1-nonyl, 1-decyl, 1-undecyl, 1-dodecyl, 1-tridecyl, 1-tetradecyl, 1-pentadecyl, 1-hexadecyl, 1-heptadecyl, 1-octadecyl, cyclopentylmethyl, 2-cyclopentylethyl, 3-cyclopentylpropyl, cyclohexylmethyl, 2-cyclohexylethyl, 3-cyclohexylpropyl, benzyl (phenylmethyl), diphenylmethyl (benzhydryl), triphenylmethyl, 1-phenylethyl, 2-phenylethyl, 3-phenylpropyl, α, α-dimethylbenzene, p-tolylmethyl, 1- (p Butylphenyl) -ethyl, p-chlorobenzyl, 2,4-dichlorobenzyl, p-methoxybenzyl, m-ethoxybenzyl, 2-cyanoethyl, 2-cyanopropyl, 2-Methoxycarbonylethy 1,2-ethoxycarbonylethyl, 2-butoxycarbonylpropyl, 1,2-di- (methoxycarbonyl) -ethyl, methoxy, ethoxy, formyl, 1,3-dioxolan-2-yl, 1,3-dioxan-2 yl, 2-methyl-1,3-dioxolan-2-yl, 4-methyl-1,3-dioxolan-2-yl, 2-hydroxyethyl, 2-hydroxypropyl, 3-hydroxypropyl, 4-hydroxybutyl, 6-hydroxyhexyl, 2-aminoethyl, 2-aminopropyl, 3-aminopropyl, 4-aminobutyl, 6-aminohexyl, 2-methylaminoethyl, 2-methylaminopropyl, 3-methylaminopropyl, 4-methylaminobutyl, 6-methylaminohexyl, 2-dimethylaminoethyl, 2- Dimethylaminopropyl, 3-dimethylaminopropyl, 4-dimethylaminobutyl, 6-dimethylaminohexyl, 2-hydroxy-2,2-dimethylethyl, 2-phenoxyethyl, 2-phenoxypropyl, 3-phenoxypropyl, 4-phenoxybutyl, 6-phenoxyhexyl, 2- Methoxyethyl, 2-methoxypropyl, 3-methoxypropyl, 4-methoxybutyl, 6-methoxyhexyl, 2-ethoxyethyl, 2-ethoxypropyl, 3-ethoxypropyl, 4-ethoxybutyl, 6-ethoxyhexyl, acetyl, C _n F 2 ( _n +) + (ib) H ₂ a + b with n equal to 1 to 30, 0 <a <n and b = 0 or 1 (for example CF ₃ , C ₂ F ₅ , CH ₂ CH ₂ -C _(n- 2) F ₂ (n.2 ) ₊ i, C ₆ F ₁₃ , C ₈ F ₁₇ , C ₁₀ F ₂₁ , C ₁₂ F ₂₅ ), chloromethyl, 2-chloroethyl, trichloromethyl, 1,1-dimethyl-2-chloroethyl, methoxymethyl, 2-butoxyethyl, diethoxymethyl , Diethoxyethyl, 2-isopropoxyethyl, 2-butoxypropyl, 2-octyloxyethyl, 2-methoxyisopropyl, 2- (methoxycarbonyl) -ethyl, 2- (ethoxycarbonyl) -ethyl, 2- (n-butoxycarbonyl) -ethyl, butylthiomethyl, 2-dodecylthioethyl , 2-phenylthioethyl, 5-hydroxy-3-oxa-pentyl, 8-hydroxy-3,6-dioxa-octyl, 11-hydroxy-3,6,9-trioxa undecyl, 7-hydroxy-4-oxa -heptyl, 11-hydroxy-4,8-dioxa-undecyl, 15-hydroxy-4,8,12-trioxa-pentadecyl, 9-hydroxy-5-oxa-nonyl, 14-hydroxy-5, 10-dioxa-tetradecyl , 5-Methoxy-3-oxa-pentyl, 8-methoxy-3,6-dioxa-octyl, 11-methoxy-3,6,9-trioxa-undecyl, 7-methoxy-4-oxa-heptyl, 11-methoxy 4,8-dioxa-undecyl, 15-methoxy-4,8,12-trioxapentadecyl, 9-methoxy-5-oxa-nonyl, 14-methoxy-5,10-dioxa-tetradecyl, 5-ethoxy-3 oxa-pentyl, 8-ethoxy-3,6-dioxa-octyl, 11-ethoxy-3,6,9-trioxa-undecyl, 7-ethoxy-4-oxa-heptyl, 11-ethoxy-4,8-dioxa -undecyl, 15 Ethoxy-4,8,12-trioxa-pentadecyl, 9-ethoxy-5-oxa-nonyl or 14-ethoxy-5,10-oxa-tetradecyl.

C ₂ optionally substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and / or heterocycles and / or interrupted by one or more oxygen and / or sulfur atoms and / or one or more substituted or unsubstituted imino groups - C ₁₈ -alkenyl is preferred to vinyl, 2-propenyl, 3-Bυtenyl, cis-2-butenyl, trans-2-butenyl or C _n F2 (n _-a ) - (ib) H2a-b with n <30, 0 ≤ a <n and b = 0 or 1.

When optionally substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and / or heterocycles C ₆ - to C ₁₂ -A17I is preferably phenyl, ToIyI, XyIyI, α-naphthyl, ß-naphthyl, 4th -Diphenylyl, chlorophenyl, dichlorophenyl, trichlorophenyl, difluorophenyl, methylphenyl, dimethylphenyl, trimethylphenyl, ethylphenyl, diethylphenyl, / so-propylphenyl, tert-butylphenyl, dodecylphenyl, methoxyphenyl, dimethoxyphenyl, ethoxyphenyl, hexyloxyphenyl, methyynaphthyl, isopropylnaphthyl, chloronaphthyl, ethoxynaphthyl , 2,6-dimethylphenyl, 2,4,6-trimethylphenyl, 2,6-dimethoxyphenyl, 2,6-dichlorophenyl, 4-bromophenyl, 2-nitrophenyl, 4-nitrophenyl, 2,4-dinitrophenyl, 2 , 6-Dinitrophenyl, 4-dimethylaminophenyl, 4-acetylphenyl, methoxyethylphenyl, ethoxymethylphenyl, methylthiophenyl, isopropylthiophenyl or tert-butylthiophenyl or C ₆ F _(S-3) H ₃ with 0 <a <5.

C ₅ -C ₁₂ -cycloalkyl optionally substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and / or heterocycles is preferably cyclopentyl, cyclohexyl, cyclooctyl, cyclododecyl, methylcyclopentyl, dimethylcyclopentyl, methylcyclohexyl , Dimethylcyclohexyl, diethylcyclohexyl, butylcyclohexyl, methoxycyclohexyl, dimethoxycyclohexyl, diethoxycyclohexyl, butylthio cyclohexyl, chlorocyclohexyl, dichlorocyclohexyl, dichlorocyclopentyl, C _n F ₂ (n..aHi-b) H 2a-b with n <30, 0 <a <n and b = 0 or 1 and a saturated or unsaturated bicyclic system such as norbornyl or norbomenyl.

When optionally substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and / or heterocycles C ₅ - to C ₁₂ cycloalkenyl is preferably 3-cyclopentenyl, 2-cyclohexenyl, 3-cyclohexenyl, 2.5 -Cyclohexa- dienyl or C _n F ₂ _(n-a) -3 (ib) H2a-3b where n <30, 0 <a <n and b = 0 or the first

An optionally substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and / or heterocycles substituted five- to six-membered, oxygen, nitrogen and / or sulfur atoms containing heterocycle is preferably furyl, thiophenyl, pyrryl, Pyridyl, indolyl, benzoxazolyl, dioxolyl, dioxo, benzimidazolyi, benzthiazolyl, dimethylpyridyl, methylquinolyl, dimethylpyrryl, methoxyfuryl, dimethoxypyridyl or difluoropyridyl.

Two adjacent radicals together form an unsaturated, saturated or aromatic, optionally substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and / or heterocycles and optionally substituted by one or more oxygen and / or sulfur atoms and / or one or more several substituted or unsubstituted imino groups interrupted ring, it is preferably 1,3-propylene, 1, 4-butylene, 1, 5-pentylene, 2-oxa-1, 3-propylene, 1-oxa-1,3- propylene, 2-oxa-1,3-propylene, 1-oxa-1, 3-propenylene, 3-oxa-1, 5-pentylene, 1-aza-1, 3-propenylene, 1 -C ₁ -C ₄ - AIKyM -aza-1, 3-propenylene, 1,4-buta-1,3-dienylene, 1-aza-1, 4-buta-1,3-dienylene or 2-aza-1, 4-buta-1, 3-dienylene.

If the abovementioned radicals contain oxygen and / or sulfur atoms and / or substituted or unsubstituted imino groups, the number of oxygen and / or sulfur atoms and / or imino groups is not restricted. As a rule, it is not more than 5 in the radical, preferably not more than 4, and very particularly preferably not more than 3.

If the abovementioned radicals contain heteroatoms, then between two heteroatoms there are generally at least one carbon atom, preferably at least two carbon atoms.

Particularly preferably, the radicals R ¹ to R ⁹ are each independently

• hydrogen;

• straight-chain or branched, unsubstituted or monosubstituted to hydroxyl, halogen, phenyl, cyano, C ₁ - to C ₆ -alkoxycarbonyl and / or sulfonic acid substituted C ₁ - to C ₁₈ -alkyl having a total of 1 to 20 carbon atoms, such as for example, methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl-1-propyl (isobutyl), 2-methyl-2-propyl (tert-butyl), 1-pentyl, 2-pentyl, 3-pentyl, 2-methyl-butyl, 3-methyl-butyl, 2-methyl-2-butyl, 3-methyl-2-butyl, 2,2-dimethyl-1-propyl, 1 Hexyl, 2-hexyl, 3-hexyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl-2-pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl,

2-methyl-3-pentyl, 3-methyl-3-pentyl, 2,2-dimethyl-1-butyl, 2,3-dimethyl-1-butyl, 3,3-dimethyl-1-butyl, 2-ethyl 1-butyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl, 1-HeptyI, 1-octyl, 1-nonyl, 1-decyl, 1-undecyl, 1-dodecyl, 1- Tetradecyl, 1-hexadecyl, 1-octadecyl, 2-hydroxyethyl, benzyl, 3-phenylpropyl, 2-cyanoethyl, 2- (methoxycarbonyl) -ethyl, 2- (ethoxycarbonyl) -ethyl, 2- (n-butoxycarbonyl ) -ethyl,

Trifluoromethyl, difluoromethyl, fluoromethyl, pentafluoroethyl, heptafluoropropyl, heptafluoroisopropyl, nonafluorobutyl, nonafluoroisobutyl, undecylfluoropentyl, undecylfluoroisopentyl, 6-hydroxyhexyl and propylsulfonic acid;

Glycols, butylene glycols and their oligomers having 1 to 100 units and a hydrogen or a C ₁ to C ₈ alkyl as an end group, such as

R ^A O- (CHR ^B -CH ₂ -O) _n -CHR ^B -CH ₂ - or

R 1 is - (CH ₂ CH ₂ CH ₂ CH ₂ O) _n -CH ₂ CH ₂ CH ₂ CH ₂ O- with R ^A and R ^{B is} preferably hydrogen, methyl or ethyl and n is preferably 0 to 3, in particular 3-oxabutyl, 3-oxapentyl, 3,6-dioxaheptyl, 3,6-dioxaoctyl, 3,6,9-trioxadecyl, 3,6,9-trioxa-undecyl, 3,6,9, 12-tetraoxatridecyl and 3,6,9, 12-tetraoxatetradecyl;

• vinyl; and • N ₁ N-di-Cr to _C6 alkyl-amino, such as N, N-dimethylamino and N ₁ N-diethylamino.

Most preferably, the radicals R ¹ to R ^{9 are} independently hydrogen or C ₁ - to C ₈ alkyl such as methyl, ethyl, 1-butyl, 1-pentyl, 1-hexyl, 1-heptyl, 1-octyl , for phenyl, for 2-hydroxyethyl, for 2-cyanoethyl, for 2- (methoxycarbonyl) ethyl, for 2- (ethoxycarbonyl) ethyl, for 2- (n-butoxycarbonyl) ethyl, for N, N-dimethylamino, for N, N-diethylamino, for chlorine and for CH ₃ O- (CH ₂ CH ₂ O) _n - CH ₂ CH ₂ - and CH ₃ CH ₂ O- (CH ₂ CH ₂ O) _n -CH ₂ CH ₂ - where n is the same O to 3.

With very particular preference in the process according to the invention, the pyridinium ions (IVa) used are those in which

• one of the radicals R ¹ to R ^{5 is} methyl, ethyl or chlorine and the remaining radicals R ¹ to R ^{5 are} hydrogen;

• R ^{3 is} dimethylamino and the remaining radicals R ¹ , R ² , R ⁴ and R ^{5 are} hydrogen;

• all radicals R ¹ to R ^{5 are} hydrogen;

• R ^{2 is} carboxy or carboxamide and the remaining radicals R ¹ , R ² , R ⁴ and R ^{5 are} hydrogen; or

• R ¹ and R ² or R ² and R ^{3 is} 1, 4-buta-1,3-dienylene and the remaining R ¹ , R ² , R ⁴ and R ^{5 are} hydrogen;

and in particular those in which

• R ¹ to R ^{5 are} hydrogen; or

• one of the radicals R ¹ to R ^{5 is} methyl or ethyl and the remaining radicals R ¹ to R ^{5 are} hydrogen.

Very particularly preferred pyridinium ions (IVa) include 1-methylpyridinium, 1-ethylpyridinium, 1- (1-butyl) pyridinium, 1- (1-hexyl) pyridinium, 1- (1-OCl) pyridinium, (1-Hexyl) -pyridinium, 1- (1-octyl) -pyridinium, 1- (1-dodecyl) -pyridinium, 1- (1-tetradecyl) -pyridinium, 1- (1-hexadecyl) -pyridinium, 1, 2-dimethylpyridinium, 1-ethyl-2-methylpyridinium, 1- (1-butyl) -2-methylpyridinium, 1- (1-hexyl) -2-methylpyridinium, 1- (1-octyl) -2-methylpyridinium, 1- (1-dodecyl) -2-methylpyridinium, 1- (1-tetradecyl) -2-methylpyridinium, 1- (1-hexadecyl) -2-methylpyridinium, 1-methyl-2-ethylpyridinium, 1, 2-diethylpyridinium, 1- (1-Butyl) -2-ethylpyridinium, 1- (1-Hexyl) -2-ethylpyridinium, 1- (1-octyl) -2-ethylpyridinium, 1- (1-Dodecyl) -2-ethylpyridinium, 1- (1-Tetradecyl) -2-ethylpyridinium, 1- (1-hexadecyl) -2-ethylpyridinium, 1, 2-dimethyl-5-ethyl-pyridinium, 1, 5-diethyl-2-methylpyridinium, 1- (1 Butyl) -2-methyl-3-ethylpyridinium, 1- (1-hexyl) -2-methyl-3-ethyl-pyridinium and 1- (1-octyl) -2-methyl-3 ethyl-pyridinium, 1- (1-dodecyl) -2-methyl-3-ethylpyridinium, 1- (1-tetradecyl) -2-methyl-3-ethylpyridinium and 1- (1-hexadecyI) -2-methyl-3- ethyl-pyridinium.

Very particular preference is given in the process according to the invention as Pyrida- ziniumionen (IVb) such, in which

• R ¹ to R ^{4 are} hydrogen; or

• one of the radicals R ¹ to R ^{4 is} methyl or ethyl and the remaining radicals R ¹ to R ^{4 are} hydrogen.

With very particular preference in the process according to the invention pyrimidinium ions (IVc) are those in which

• R ^{1 is} hydrogen, methyl or ethyl and R ² to R ^{4 are} independently hydrogen or methyl; or

• R ^{1 is} hydrogen, methyl or ethyl, R ² and R ^{4 are} methyl and R ^{3 is} hydrogen.

Very particular preference is given in the process according to the invention as Pyrazi- niumionen (IVd) those in which

• R ^{1 is} hydrogen, methyl or ethyl and R ² to R ^{4 are} independently hydrogen or methyl;

• R ^{1 is} hydrogen, methyl or ethyl, R ² and R ^{4 are} methyl and R ^{3 is} hydrogen;

• R ¹ to R ^{4 are} methyl; or

• R ¹ to R ^{4 are} methyl hydrogen.

With very particular preference in the process according to the invention, the imidazolium ions (IVe) used are those in which

• R ^{1 is} hydrogen, methyl, ethyl, 1-propyl, 1-butyl, 1-pentyl, 1-hexyl, 1-octyl, 2-hydroxyethyl or 2-cyanoethyl and R ² to R ^{4 are} independently hydrogen, methyl or ethyl ,

Very particularly preferred imidazolium ions (IVe) which may be mentioned are 1-methylimidazolium, 1-ethylimidazolium, 1- (1-butyl) -imidazolium, 1- (1-octyl) -imidazolium, 1- (1-dodecyl) -imidazolium, 1- (1-Tetradecyl) -imidazolium, 1- (1-hexadecyl) -imidazolium, 1,3-dimethylimidazolium, 1-ethyl-3-methylimidazolium, 1- (1-butyl) -3-methylimidazolium, 1- (1 Butyl) -3-ethylimidazolium, 1- (1-hexyl) -3-methylimidazolium, 1- (1-hexyl) -3-ethylimidazolium, 1- (1-hexyl) -3-butylimidazolium, 1- (1-octyl) -3-methylimidazolium, 1- (1-octyl) -3-ethylimidazolium, 1- (1-octyl) -3-butylimidazolium, 1- (1-dodecyl) -3-methyl imidazolium, 1- (1-dodecyl) -3-ethylimidazolium, 1- (1-dodecyl) -3-butylimidazolium, 1- (1-dodecyl) -3-octylimidazolium, 1- (1-tetradecyl) -3-methylimidazolium, 1- (1-tetradecyl) -3-ethylimidazolium, 1- (1-tetradecyl) -3-butylimidazolium, 1- (1-tetradecyl) -3-octylimidazolium, 1- (1-hexadecyl) -3-methylimidazolium, 1- (1-hexadecyl) -3-ethylimidazolium, 1- (1-hexadecyl) -3-butylimidazolium, 1- (1-hexadecyl) -3-octylimidazolium, 1,2-dimethylimidazolium, 1,2,3- Trimethylimidazolium, 1-ethyl-2,3-dimethylimidazolium, 1- (1-butyl) -2,3-dimethylimidazolium, HI-hexoxy-O,.-Dimethyl imidazolium, 1- (1-octyl) -2,3-di - Methylimidazolium, 1, 4-dimethylimidazolium, 1, 3,4-trimethylimidazolium, 1, 4-dimethyl-3-ethylimidazolium, 3-butylimidazolium, 1, 4-dimethyl-3-octylimidazolium, 1, 4,5-trimethylimidazolium , 1, 3,4,5-tetramethylimidazolium, 1, 4,5-trimethyl-3-ethylimidazolium, 1,4,5-trimethyl-3-butylimidazolium and 1,4,5-trimethyl-3-octylimidazolium ,

Very particular preference is given in the process according to the invention as Pyrazo- liumionen (IVf), (IVg) or (IVg ') such, in which

• R ^{1 is} hydrogen, methyl or ethyl and R ² to R ^{4 are} independently hydrogen or methyl.

In the process according to the invention, very particular preference is given to using pyrazolium ions (IVh) as those in which

• R ¹ to R ^{4 are} independently hydrogen or methyl.

Very particular preference is given in the process according to the invention as 1-pyrazolinium (IVi) such as those in which

• independently of one another R ¹ to R ^{6 are} hydrogen or methyl.

Very particular preference is given in the process according to the invention as 2-pyrazolinium (IVj) or (IVj ') such, in which

• R ^{1 is} hydrogen, methyl, ethyl or phenyl and R ² to R ^{6 are} independently hydrogen or methyl.

Very particular preference is given in the process according to the invention as 3-pyrazolinium (IVk) or (IVk ') such, in which

• R ¹ and R ^{2 are} independently hydrogen, methyl, ethyl or phenyl and R ³ to R ^{6 are} independently hydrogen or methyl. With very particular preference in the process according to the invention, imidazoline ions (IVI) are those in which

• R ¹ and R ^{2 are} independently hydrogen, methyl, ethyl, 1-butyl or phenyl, R ³ and R ^{4 are} independently hydrogen, methyl or ethyl, and R ⁵ and R ^{6 are} independently hydrogen or methyl.

In the process according to the invention, very particular preference is given to using imidazolium ions (IVm) or (IVm ') as those in which

• R ¹ and R ^{2 are} independently hydrogen, methyl or ethyl and R ³ to R ^{6 are} independently hydrogen or methyl.

With very particular preference in the process according to the invention, the imidazolium ions (IVn) or (IVn ') used are those in which

• R ¹ to R ^{3 are} independently hydrogen, methyl or ethyl and R ⁴ to R ^{6 are} independently hydrogen or methyl.

Very particular preference is given in the process according to the invention as Thiazo liumionen (IVo) or (IVo ') and as Oxazoliumionen (IVp) such, in which

• R ^{1 is} hydrogen, methyl, ethyl or phenyl and R ² and R ^{3 are} independently of one another hydrogen or methyl.

Very particular preference is given to the process according to the invention as 1, 2,4-triazolium (IVq), (IVq ¹ ) or (IVq ") such, in which

• R ¹ and R ^{2 are} independently hydrogen, methyl, ethyl or phenyl and R ^{3 is} hydrogen, methyl or phenyl.

Very particular preference is given to the process according to the invention as 1, 2,3-Triazoliumionen (IVr), (IVr ') or (IVr ") such, in which

• R ^{1 is} hydrogen, methyl or ethyl and R ² and R ^{3 are} independently hydrogen or methyl, or R ² and R ³ together are 1, 4-buta-1, 3-dienylene.

With very particular preference in the process according to the invention, the pyrrolinedinium ions (IVs) used are those in which • R ^{1 is} hydrogen, methyl, ethyl or phenyl and R ² to R ^{9 are} independently hydrogen or methyl.

Very particular preference is given in the process according to the invention as imidazolidinium ions (IVt) to those in which

• R ¹ and R ^{4 are} independently hydrogen, methyl, ethyl or phenyl and R ² and R ³ and R ⁵ to R ^{8 are} independently hydrogen or methyl.

With very particular preference in the process according to the invention, the ammonium ions (IVu) used are those in which

• R ¹ to R ^{3 are} independently of each other Cr to C ₁₈ alkyl; or R ¹ and R ² together are 1,5-pentylene or 3-oxa-1,5-pentylene and R ^{3 is} C ₁ -C ₁₈ -alkyl, 2-hydroxyethyl or 2-cyanoethyl.

As very particularly preferred ammonium ions (IVu) may be mentioned methyl tri (1-butyl) -ammonium, N, N-dimethylpiperidinium and N, N-dimethylmorpholinium.

Very particularly preferably, in the process according to the invention, guanidinium ions (IVv) are those in which

• R ¹ to R ^{5 are} methyl.

As a very particularly preferred guanidinium ion (IVv) may be mentioned N, N, N ', N', N ", N" - hexamethylguanidinium.

Very particular preference is given in the process according to the invention as cholinium ions (IVw) such as those in which

• R ¹ and R ^{2 are} independently methyl, ethyl, 1-butyl or 1-octyl and R ^{3 is} hydrogen, methyl, ethyl, acetyl, -SO ₂ OH or -PO (OH) ₂ ;

• R ^{1 is} methyl, ethyl, 1-butyl or 1-octyl, R ^{2 is} a -CH ₂ -CH ₂ -OR ⁴ group and R ³ and R ^{4 are} independently hydrogen, methyl, ethyl, acetyl, -SO ₂ OH or -PO (OH) ₂ ; or

• R ^{1 is} a -CH ₂ -CH ₂ -OR ⁴ group, R ^{2 is} a -CH ₂ -CH ₂ -OR ⁵ group and R ³ to R ^{5 are} independently hydrogen, methyl, ethyl, acetyl, -SO _{2 are} OH or - PO (OH) ₂ .

Very particularly preferably, in the process according to the invention, phosphonium ions (IVx) are used as those in which • R ¹ to R ^{3 are} independently C ₁ -C ₁₈ -AlkVl, especially butyl, isobutyl, 1-hexyl or 1-octyl.

Among the cations mentioned above, the pyridinium ions (IVa), imidazolium ions (IVe) and ammonium ions (IVu) are preferred, in particular 1-methylpyridinium, 1-ethylpyridinium, 1- (1-butyl) pyridinium, 1- (1-hexyl) pyridinium, 1- (1-octyl) pyridinium, 1- (1-hexyl) -pyridinium, 1- (1-octyl) -pyridinium, 1- (1-dodecyl) -pyridinium, 1- (1-tetra-decyl) -pyridinium, 1- (1-hexadecyl) -pyridinium, 1, 2-dimethylpyridinium, 1-ethyl-2-methylpyridinium, 1- (1-butyl) -2-methylpyridinium, 1- (1-hexyl) -2-methylpyridinium , 1- (1-Octyl) -2-methylpyridinium, 1- (1-dodecyl) -2-methylpyridinium, 1- (1-tetradecyl) -2-methylpyridinium, 1- (1-hexadecyl) -2-methylpyridinium, 1 -Methyl 2-ethylpyridinium, 1,2-diethylpyridinium, 1- (1-butyl) -2-ethylpyridinium, 1- (1-HexyI) -2-ethylpyridinium, 1- (1-Octyl) -2-ethylpyridinium, 1 - (1-dodecyl) -2-ethylpyridinium, 1- (1-tetradecyl) -2-ethylpyridinium, 1- (1-hexadecyl) -2-ethylpyridinium, 1, 2-dimethyl-5-ethyl-pyridinium, 1 , 5-diethyl-2-methyl-pyridinium, 1- (1-butyl) -2-methyl-3-ethyl-pyridine ium, 1- (1-hexyl) -2-methyl-3-ethylpyridinium, 1- (1-octyl) -2-methyl-3-ethylpyridinium, 1- (1-dodecyl) -2-methyl- 3-ethyl-pyridinium, 1- (1-tetradecyl) -2-methyl-3-ethylpyridinium, 1- (1-hexadecyl) -2-methyl-3-ethylpyridinium, 1-methylimidazolium, 1 Ethylimidazolium, 1- (1-butyl) -imidazolium, 1- (1-octyl) -imidazolium, 1- (1-dodecyl) -imidazolium, 1- (1-tetradecyl) -imidazolium, 1- (1-hexadecyl ) imidazolium, 1,3-dimethylimidazolium, 1-ethyl-3-methylimidazolium, 1- (1-butyl) -3-methylimidazolium, 1- (1-hexyl) -3-methylimidazolium, 1- (1-octyl ) -3-methylimidazolium, 1- (1-dodecyl) -3-methylimidazolium, 1- (1-tetradecyl) -3-methylimidazolium, 1- (1-hexadecyl) -3-methylimidazolium, 1,2-dimethylimidazolium, 1, 2,3-trimethylimidazolium, 1-ethyl-2,3-dimethylimidazolium, 1- (1-butyl) -2,3-dimethylimidazolium, 1- (1-HexyI) -2,3-dimethylimidazolium and 1- (1-butyl) -2,3-dimethylimidazolium; (1-Octyl) -2,3-dimethylimidazolium, 1,4-dimethylimidazolium, 1,3,4-trimethylimidazolium, 1,4-dimethyl-3-ethylimidazolium, 3-butylimidazolium, 1.4 -Dimethyl-3-octylimidazolium, 1, 4,5-trimethylimidazolium, 1, 3,4,5-tetramethylimidazolium, 1, 4,5-trimethyl-3-ethylimidazolium, 1,4,5-trimethyl-3-butylimidazolium and 1, 4,5-trimethyl-3-octyl-imidazolium.

The metal cations [M ¹ ] ⁺ , [M ² ] ⁺ , [M ³ J ⁺ , [M ⁴ ] ²⁺ and [M ⁵ ] ³⁺ mentioned in formulas (IIIa) to (MIj) are generally to metal cations of the 1st, 2nd, 6th, 7th, 8th, 9th, 10th, 11th, 12th and 13th group of the periodic table. Suitable metal cations are, for example, Li ⁺ , Na ⁺ , K ⁺ , Cs ⁺ , Mg ²⁺ , Ca ²⁺ , Ba ²⁺ , Cr ³⁺ , Fe ²⁺ , Fe ³⁺ , Co ²⁺ , Ni ²⁺ , Cu ^{2 +} , Ag ⁺ , Zn ²⁺ and Al ³⁺ .

As anions, in principle, all anions can be used which, in conjunction with the cation, lead to an ionic liquid.

The anion [Y] ^{π "of} the ionic liquid is for example selected from:

The group of halides and halogen-containing compounds of the formulas: F, Cr, Br, r, BF ₄ ^" , PF ₆ -, AlCl ₄ -, Al ₂ Cl ₇ -, Al ₃ Cl ₁₀ , AIBr ₄ -, FeCl ₄ -, BCI ₄ ^" , SbF ₆ ^" , AsF ₆ , ^" ZnCl ₃ -, SnCl ₃ ^" , CuCl ₂ -, CF ₃ SO ₃ ^" , (CF ₃ SO ₃ ) ₂ N-, CF ₃ CO ₂ -, CCI ₃ CO ₂ -, CN ^" , SCN ^" , OCN-, NO ^{2 '} , NO ^{3 "} , N (CN) -;

The group of sulfates, sulfites and sulfonates of the general formulas: SO ₄ ^{2 "} , HSO ₄ -, SO ₃ ^2" , HSO ₃ -, R ³ OSO ₃ ^" , R ³ SO ₃ ^' ;

The group of phosphates of the general formulas: PO ₄ ^{3 "} , HPO ₄ ^2" , H ₂ PO ₄ -, R ³ PO ₄ ^{2 "} , HR ³ PO ₄ ^" , R ³ R ^b PO ₄ ^" ;

The group of phosphonates and phosphinates of the general formula: R ³ HPO ₃ -, R ³ R ¹³ PO ₂ ^' , R ³ R ¹³ PO ₃ -; The group of phosphites of the general formulas: PO ₃ ^{3 "} , HPO ₃ ^2" , H ₂ PO ₃ ^" , R ³ PO ₃ ^2" , R ³ HPO ₃ ^" , R ³ R ¹³ PO ₃ ^" ;

The group of phosphonites and phosphinites of the general formula: R ³ R ^b PO ₂ ^" , R ³ HPO ₂ ^" , R ^a R ^b PO ^" , R ³ HPO ^" ;

• the group of carboxylates of the general formulas: R ³ COO ^" ;

The group of borates of the general formulas:

BO ₃ ^{3 "} , HBO ₃ ^2" , H ₂ BO ₃ ^" , R ³ R ¹³ BO ₃ ^" , R ³ HBO ₃ ^" , R ³ BO ₃ ^2" , B (OR ^a ) (OR ^b ) (OR °) (OR ^d) -, B (HSO ₄₎ ^', B (R ³ SO 4) ^";

• the group of boronates of the general formulas: R ³ BO ₂ ^{2 "} , R ³ R ^b B0 ^" ;

The group of carbonates and carbonic esters of the general formulas: HCO ₃ ^" , CO ₃ ^2" , R ³ CO ₃ -;

The group of silicates and silicic acid esters of the general formulas: SiO ₄ ^{4 "} , HSiO ₄ ^3" , H ₂ SiO ₄ ^{2 "} , H ₃ SiO ₄ ^" , R ³ SiO ₄ ^{3 "} , R ³ R ¹³ SiO ₄ ^2" , R ³ R ¹³ R ⁰ SiO ₄ ^" , HR ³ SiO ₄ ^2" , H ₂ R ³ SiO ₄ ^" , HR ³ R ¹³ SiO ₄ ^" ;

The group of the alkyl or aryl silane salts of the general formulas: R ³ SiO ₃ ^{3 "} , R ³ R ¹³ SiO ₂ ^2" , R ³ R ¹³ R ⁰ SiO ^" , R ³ R ¹³ R ⁰ SiO ₃ ^" , R ³ R ¹³ R ⁰ SiO ₂ ^" , R ^a R ^b Si0 ₃ ^2" ;

The group of the carboxylic imides, bis (sulfonyl) imides and sulfonyl imides of the general formulas:

The group of methides of the general formula: SO ₂ -R ³

R ^b -O ₂ S SO ₂ -R =

• the group of alkoxides and aryloxides of the general formulas: R ³ O ^' • the group of the halometallates of the general formula [M _q Hal _r f, where M is a metal and Hal is fluorine, chlorine, bromine or iodine, q and r are all positive numbers and indicate the stoichiometry of the complex and s is a whole positive number indicating the charge of the complex • the group of sulfides, hydrogen sulfides, polysulfides, hydrogen polysulfides and thiolates of the general formula: S ² -, HS ^" , [ S _v ] ² -, [HS _V ] -, [R ³ S] -, where v is a whole positive number from 2 to 10;

• the group of complex metal ions such as Fe (CN) ₆ ^{3 "} , Fe (CN) ₆ ^{4 '} , MnO ₄ ^" , Fe (CO) ₄ ^" .

In this R ^a , R ^b , R ° and R ^d are each independently

• hydrogen; C ₁ - to C ₃₀ -alkyl and their aryl, heteroaryl, cycloalkyl, halogen, hydroxy, amino, carboxy, formyl, -O-, -CO-, -CO-O- or - CO-N <substituted components such as methyl, ethyl, 1-propyl, 2-propyl, 1-butyl, 2-butyl, 2-methyl-1-propyl (isobutyl), 2-methyl-2-propyl (tert. Butyl), 1-pentyl, 2-pentyl, 3-pentyl, 2-methyl-1-butyl, 3-methyl-1-butyl, 2-methyl-2-butyl, 3-methyl-2-butyl, 2, 2-dimethyl-1-propyl, 1-hexyl, 2-hexyl, 3-hexyl, 2-methyl-1-pentyl, 3-methyl-1-pentyl, 4-methyl-1-pentyl, 2-methyl-2- pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 2-methyl-3-pentyl, 3-methyl-3-pentyl, 2,2-dimethyl-1-butyl, 2,3-dimethyl 1-butyl, 3,3-dimethyl-1-butyl, 2-ethyl-1-butyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl, heptyl, octyl, nonyl, decyl, Undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, icosyl, henicosyl, docosyl, tricosyl, tetracosyl, pentacosyl, hexacosyl, heptacosyl, octacosyl, nonacosyl, triacontyl, phenyl methyl (benzyl), diphenylmethyl, triphenylmethyl, 2-phenylethyl, 3-phenylpropyl, cyclopentylmethyl, 2-cyclopentylethyl, 3-cyclopentylpropyl, cyclohexylmethyl, 2-cyclohexylethyl, 3-cyclohexylpropyl, methoxy, ethoxy, formyl, acetyl or C _π F ₂ (na) + (ib) H ₂ a + b with n ≤ 30, O <a <n and b = O or

1 (e.g. CF ₃ , C ₂ F ₅ , CH ₂ CH ₂ -C _(n- 2) F ₂ (n-2) ₊ i, C ₆ F ₁₃ , C ₈ F ₁₇ , C ₁₀ F ₂ - _I , C ₁₂ F ₂₅ );

• C ₃ - to Ci ₂ cycloalkyl, and whose aryl, heteroaryl, cycloalkyl, halo, hydroxy, amino, carboxy, formyl, -O-, -CO- or -CO-0-substituted compo - nenten, such as cyclopentyl, 2-methyl-1-cyclopentyl, 3-methyl-1-cyclopentyl, cyclohexyl, 2-methyl-1-cyclohexyl, 3-methyl-1-cyclohexyl, 4-methyl-1-cyclohexyl or C _n F ₂ (n-αMi-b ₎ H ₂ ab with n <30, 0 ≤ a <n and b = 0 or 1;

C ₂ to C ₃₀ alkenyl and their aryl, heteroaryl, cycloalkyl, halogen, hydroxy, amino, carboxy, formyl, -O-, -CO- or -CO-O-substituted components , such as 2-propenyl, 3-butenyl, cis-2-butenyl, trans-2-butenyl or CnF ₂ (na) - (ib) H2a-b with n <30, 0 <a <n and b = 0 or 1 ;

• C ₃ - to C ₁₂ cycloalkenyl and their aryl, heteroaryl, cycloalkyl, halogen, hydroxy, amino, carboxy, formyl, -O-, -CO- or -CO-O-substituted Kompo - Nenten, such as 3-cyclopentenyl, 2-cyclohexenyl, 3-cyclohexenyl,

2,5-cyclohexadienyl or C _n F ₂ (na) -3 (ib) H _{2 a 3 b} with n <30, 0 <a <n and b = 0 or

1;

Aryl or heteroaryl having 2 to 30 carbon atoms and their alkyl, aryl, heteroaryl, cycloalkyl, halogen, hydroxy, amino, carboxy, formyl, -O-, -CO- or -CO-O -substituted components such as phenyl, 2-methylphenyl

(2-ToIyI) ₁ 3-Methyl-phenyl (3-tolyl), 4-methylphenyl, 2-ethylphenyl, 3-ethylphenyl, 4-ethylphenyl, 2,3-dimethylphenyl, 2 , 4-dimethyl-phenyl, 2,5-dimethyl-phenyl, 2,6-dimethyl-phenyl, 3,4-dimethyl-phenyl, 3,5-dimethyl-phenyl, 4-phenyl-phenyl, 1-naphthyl, 2 -Naphthyl, 1-pyrrolyl, 2-pyrrolyl, 3-pyrrolyl, 2-pyridinyl, 3-pyridinyl, 4-pyridinyl or C ₆ F ₍₅ .a ₎ H _a with 0 <a <5; or

• two radicals an unsaturated, saturated or aromatic, optionally substituted by functional groups, aryl, alkyl, aryloxy, alkyloxy, halogen, heteroatoms and / or heterocycles and optionally substituted by one or more oxygen and / or sulfur atoms and / or one or more substituted or unsubstituted imino groups interrupted ring.

Very particularly preferred anions are chloride; Bromide; iodide; thiocyanate; Hexafluorophosphate; trifluoromethanesulfonate; methane; formate; Acetate; mandelate; Nitrate; Nitrite; trifluoroacetate; Sulfate; Bisulfate; Methyl sulfate; ethyl sulfate; 1-propyl sulfate; 1-butyl sulfate; 1-hexyl sulfate; 1-octyl sulfate; Phosphate; dihydrogen phosphate; Hydrogen phosphate; C ₁ to C ₄ dialkyl phosphates; propionate; tetrachloroaluminate; AI ₂ CI ₇ ^' ; chlorozincate; Chloroferrat; Bis (trifluoromethylsulfonyl) imide; Bis (pentafluoroethylsulfonyl) imide; Bis (methylsulfonyl) imide; Bis (p-tolylsulfonyl) imide; Tris (trifluoromethylsulfonyl) methide; Bis (pentafluoroethylsulfonyl) methide; p-tolylsulfonate; Tetracarbonyl cobalada; Dimethylenglykolmonomethylethersulfat; oleate; stearate; acrylate; methacrylate; maleate; hydrogen citrate; vinylphosphonate; Bis (pentafluoroethyl) phosphinate; Borates such as bis [salicylato (2 -)] borate, bis [oxalato (2 -)] borate, bis [1,2-benzenediolato (2 -) - 0,0 '] borate, tetracyano borate, tetrafluoroborate; dicyanamide; Tris (pentafluoroethyl) trifluorophosphate; Tris (heptafluoropropyl) trifluorophosphate, cyclic aryl phosphates such as catechol phosphate (C ₆ H ₄ O ₂ ) P (O) O ^" and chlorocobaltate.

For the method according to the invention very particularly preferred are the Chlorides, bromides, hydrogen sulfates, tetrachloroaluminates, thiocyanates, methyl sulfates, ethyl sulfates, methanesulfonates, acetates, dimethyl phosphates, diethyl phosphates, p-toluenesulfonates, tetrafluoroborates and hexafluorophosphates

from

Methyl tri (1-butyl) ammonium, 1-methylimidazolium, 1-ethylimidazolium, 1- (1-butyl) imidazolium, 1- (1-octyl) -imidazolium, 1- (1-dodecyl) -imidazolium, 1- (1-tetradecyl) imidazolium, 1- (1-hexadecyl) -imidazolium, 1,3-dimethylimidazolium, 1-ethyl-3-methylimidazolium, 1- (1-butyl) -3-methylimidazolium, 1- (1-Butyl) -3-ethylimidazolium, 1- (1-hexyl) -3-methyl-imidazolium, 1- (1-hexyl) -3-ethyl-imidazolium, 1- (1-hexyl) -3-butyl imidazolium, 1- (1-octyl) -3-methylimidazolium, 1- (1-octyl) -3-ethylimidazolium, 1- (1-octyl) -3-butylimidazolium, 1- (1-dodecyl) -3-methylimidazolium, 1- (1-dodecyl) -3-ethylimidazolium, 1- (1-dodecyl) -3-butylimidazolium, 1- (1-dodecyl) -3-octylimidazolium, 1- (1-tetradecyl) -3-methylimidazolium, 1- (1-tetradecyl) -3-ethylimidazolium, 1- (1-tetra-decyl) -3-butylimidazolium, 1- (1-tetradecyl) -3-octylimidazolium, 1- (1-hexadecyl) -3-methylimidazolium, 1- (1-hexadecyl) -3-ethylimidazolium, 1- (1-hexadecyl) -3-butylimidazolium, 1- (1-hexadecyl) -3-octylimidazolium, 1,2-dimethylimidazolium, 1,2,3-trimethylimidazolium, 1-ethyl-2,3-dimethylimidazolium, 1- (1-butyl) -2,3-dimethylimidazolium, 1- (1-hexyl) -2,3-dimethyl- imidazolium, 1- (1-octyl) -2,3-dimethylimidazolium, 1,4-dimethylimidazolium, 1,3,4-trimethylimidazolium, 1,4-dimethyl-3-ethylimidazolium, 3-butylimidazolium, 1,4- Dimethyl-3-octylimidazolium, 1, 4,5-trimethylimidazolium, 1, 3,4,5-tetramethylimidazolium, 1, 4,5-trimethyl-3-ethylimidazolium, 1,4,5-trimethyl-3-butylimidazolium, and 1,4,5-trimethyl-3-octylimidazolium.

In particular, in the process according to the invention, 1,3-dimethylimidazolium methylsulfate, 1,3-dimethylimidazolium hydrogensulfate, 1,3-dimethylimidazolium dimethyl phosphate, 1-ethyl-3-methylimidazolium methylsulfate, 1-ethyl-3-methylimide azolium hydrogensulfate, 1-ethyl-3-methylimidazolium thiocyanate, 1-ethyl-3-methylimidazolium acetate, 1-ethyl-3-methylimidazolium methanesulfonate, 1-ethyl-3-methylimidazolium diethyl phosphate, 1- (1-butyl ) -3-methylimidazolium methylsulfate, 1- (1-butyl) -3-methylimidazolium hydrogensulfate, 1- (1-butyl) -3-methylimidazolium thiocyanate, 1- (1-butyl) -3-methylimidazolium acetate, 1- (1 Butyl) -3-methylimidazolium methanesulfonate, 1- (1-dodecyl) -3-methylimidazolium methylsulfate, 1- (1-dodecyl) -3-methylimidazolium hydrogensulfate, 1- (1-tetradecyl) -3-methylimidazolium methylsulfate, 1- (1-tetradecyl) -3-methylimidazolium hydrogen sulfate, 1- (1-hexadecyl) -3-methylimidazolium methylsulfate or 1- (1-hexadecyl) -3-methylimidazolium hydrogen sulfate.

According to the invention, it has been recognized that, in particular, the methyl sulfates have very good thermal stability and can therefore be used successfully even at a temperature of several hundred ^C. In the method according to the invention is generally a barrier liquid, which under operating conditions has a kinematic viscosity of 0.1 to 1000 mm ² / s and preferably 0.5 to 500 mm ² / s and more preferably 1 to 100 mm ² / s. Under operating conditions are to be understood all those conditions to which the barrier liquid is exposed in normal operation in the area of the mechanical seal and which have an influence on the viscosity. This does not explicitly include the area outside the housing of the rotating shaft, for example the area of a possibly existing expansion tank, a possibly existing cooler, a circulatory pump and any existing pipelines, since in these areas viscosities also quite well outside the range mentioned can be acceptable. Due to the strong dependence of the viscosity on the temperature, this is, in addition to the chemical nature and composition of the barrier liquid, the virtually decisive parameter for the resulting viscosity. With one and the same substance or mixture, an increase in the temperature leads to a reduction in the viscosity and vice versa. Thus, in applications at a low operating temperature (eg room temperature), barrier liquids are preferably used which have the desired viscosity at this low temperature. In contrast, barrier fluids which have a rather high viscosity at low temperature are generally used preferably at higher operating temperatures at which they then have the desired viscosity. Thus, the selection of suitable barrier fluid also depends on the existing operating temperature.

With a kinematic viscosity of <0.1 mm ² / s, the barrier liquid is usually so thin and at a kinematic viscosity of> 1000 mm ² / s, the barrier liquid usually so thick that in both extreme cases only under special conditions, such as a very slow rotating shaft or significant compromises in tightness and lubricity, still an acceptable result can be achieved.

In addition to the above-mentioned sealing and lubricating effect, the barrier liquid is generally also used to dissipate the heat generated by the friction in the region of the mechanical seal. Therefore, in the process according to the invention, a barrier liquid is generally used which, under operating conditions, has a heat capacity in the range from 0.5 to 20 J / gK, preferably 1 to 10 J / gK and particularly preferably 1 to 5 J / gK.

The barrier liquid to be used in the process according to the invention may additionally contain additional substances in addition to the ionic liquid. Suitable additional substances are in particular those known from the prior art and hitherto customary barrier fluids, such as water, hydraulic oils, glycols, diesel, light Lubricating oils, synthetic high-temperature oils, but also alcohols. If, in addition to the ionic liquid, further substances are used, these are preferably water, ethylene glycol and / or an oil. In particular, ionic liquids with hydrophobic radicals such as, for example, alkyl radicals having> 8 carbon atoms are partially or even completely miscible with oils.

The additional substances are generally used to improve certain properties of the barrier liquid. For example, by the presence of water, which has a kinematic viscosity of about mm 1.75 ² / s at 25 ° C and from about 0.36 mm ² / s at 80 ⁰ C and a heat capacity of about 4.19 J / gK at 80 ⁰ C, the viscosity is significantly reduced and increases the heat capacity. Also by the addition of ethylene glycol or a suitable oil, the viscosity is reduced and optionally the heat capacity is increased slightly.

In the process according to the invention, a barrier liquid is generally employed which contains from 1 to 100% by weight, preferably from 10 to 100% by weight, more preferably from 50 to 100% by weight, very preferably from 95 to 100% by weight .-%, in particular to 99 to 100 wt .-% and very specifically consists entirely of the ionic liquid except for the usual impurities.

The inventive method can be used in a variety of types and designs of mechanical seals for sealing rotating shafts. Thus, the method according to the invention can be used, for example, in single-acting and multiple-acting mechanical seals both in unpressurized and in pressurized form. Furthermore, the inventive method can also be used in systems with external circuit, internal or external cooling, external expansion tank, internal or external circulation device (in forced circulation) or even in a natural cycle (thermosiphon effect).

Also in the choice of the sliding ring materials known and technically customary can be used. Thus, the conventional and widely used Gleitringmaterialien of silicon carbide, tungsten carbide, graphite, Kalrez ^®, Viton ^® and PTFE (as a representative of fluorinated polymers) can be used.

The rotating shafts sealed by the method according to the invention can be, for example, part of agitators, mixers, pumps, turbines, generators, compressors or compressors.

The implementation of the method according to the invention is explained in more detail below with reference to FIGS. 1 and 2. The following legend must be observed: A: product page

B: outside

C: rotating shaft

D: spring

E: Secondary sealing ring of the sliding ring

F: sliding ring

G: counter ring

H: Secondary sealing ring of the counter ring

I: barrier fluid

Fig. 1 shows the scheme of a single-acting mechanical seal. The barrier fluid is in the area marked "I". The counter ring "G" is connected to the rigid housing and sealed with the secondary sealing ring "H" to the product side "A" out. The rotating sliding ring "F" is connected to the rotating shaft via the secondary sealing ring "E".

Fig. 2 shows the scheme of a double-acting mechanical seal (back-to-back arrangement). In this embodiment, the rotary seal ring "F" is to be sealed to both the product side counter ring "G" and the outside counter ring "G". The barrier fluid is in the area marked "I". This has a, marked with an arrow inlet and outlet for externally connected components. The externally connected components may be, for example, coolers, equalizing tanks or circulating pumps.

The inventive method allows the sealing of rotating shafts using mechanical seals, which works well and reliably even at high temperatures, no or only a subordinate and thus tolerable interaction with a variety of different product systems shows in chemical-engineering applications and yet only one low leakage. Ionic liquids are very temperature-stable and chemically inert, so that they are prone to decomposition, coking or chemical reaction with many other substances. Thus, applications in the high temperature range, for example in the production and processing of polymers, are possible. They also have virtually no (or very low) vapor pressure, and the solubility of most of the gases present in chemical engineering applications in these ionic liquids is very low, so there is virtually no risk of uncontrolled formation of gas bubbles in locally overheated areas corresponding negative consequences. Furthermore, depending on the particular ion pair and the working temperature, ionic liquids have a low to medium viscosity, which ultimately results in the system-adapted choice of the ionic liquid according to the working temperature, the surface velocity of the rotating "

26 permitting shaft (corresponding to the shaft diameter and speed) and the desired tightness allows.

The method according to the invention can easily be used for the operation of the usual mechanical seals on the market, so that no structural changes are required and existing systems can be converted without any problems.

Examples

example 1

To prove the suitability of ionic liquids as sealing fluid for mechanical seals, the kinematic viscosity at 25 ° C and 80 ⁰ C and the heat capacity were determined for a number of different ionic liquids. An overview of these data can be found in Table 1.

The measured viscosities show that the ionic liquids can be used at different temperatures depending on their physical properties. For example, EMIM AICI ₄ , EMIM SCN, EMIM EtOSO ₃ , EMIM CH ₃ SO ₃ , EMIM Acetate, BMIM AICI ₄ and BMIM SCN are perfectly suited as barrier fluids even at 25 ° C operating temperature. MeNBu ₃ MeOSO ₃ , HMIM Cl, HMIM HSO ₄ , EMIM Cl, EMIM HSO ₄ , EMIM AICI ₄ , EMIM SCN, EMIM EtOSO ₃ , EMIM CH ₃ SO ₃ , EMIM acetate, BMIM Cl, BMIM HSO ₄ , BMIM AICI ₄ , BMIM SCN, BMIM MeO- SO _3, CH ₃ SO ₃ BMIM, BMIM acetate and EMMIM EtOSO ₃ are eminently suitable for an operating temperature of 80 ⁰ C as a barrier fluid.

The table can be finally seen that particular EMIM AICI _4, EMIM SCN, EMIM EtOSO _3, EMIM CH ₃ SO _3, EMIM acetate, BMIM AICI ₄ and BMIM SCN both at 25 ⁰ C and at 80 ⁰ C and about a wide temperature range can be used very well as a barrier liquid.

Table 1: Physical data of various ionic liquids

nb: not determined.

Claims

oo 28Patent claims

1. A method for sealing rotating shafts using mechanical seals, characterized in that one uses a barrier liquid containing an ionic liquid.

2. The method according to claim 1, characterized in that one uses as ionic liquid, an ionic liquid having a melting point of -50 ⁰ C (223 K) to 150 ⁰ C (423 K).

3. Process according to claims 1 to 2, characterized in that the ionic liquid as the

Chlorides, bromides, hydrogen sulfates, tetrachloroaluminates, thiocyanates, methyl sulfates, ethyl sulfates, methanesulfonates, acetates, dimethyl phosphates,

Diethyl phosphates, p-tolylsulfonates, tetrafluoroborates and hexafluorophosphates

from

Methyl tri (1-butyl) ammonium, 1-methyl imidazolium, 1-ethyl imidazolium, 1- (1

Butyl) -imidazolium, 1- (1-octyl) -imidazolium, 1- (1-dodecyl) -imidazolium, 1- (1-tetradecyl) -imidazolium, 1- (1-hexadecyl) -imidazolium, 1,3-dimethylimidazolium , 1-ethyl-3-methylimidazolium, 1- (1-butyl) -3-methylimidazolium, 1- (1-butyl) -3-ethylimidazolium, 1- (1-hexyl) -3-methyl-imidazolium, 1- ( 1-hexyl) -3-ethylimidazolium, 1- (1-hexyl) -3-butylimidazolium, 1- (1-octyl) -3-methylimidazolium,

1- (1-octyl) -3-ethylimidazolium, 1- (1-octyl) -3-butylimidazolium, 1- (1-dodecyl) -3-methylimidazolium, 1- (1-dodecyl) -3-ethylimidazolium, 1- (1-dodecyl) -3-butylimidazolium, 1- (1-dodecyl) -3-octylimidazolium, 1- (1-tetradecyl) -3-methylimidazolium, 1- (1-tetradecyl) -3-ethylimidazolium, 1- (1-tetradecyl) -3-butylimidazolium, 1- (1-tetradecyl) -3-octylimidazolium, 1- (1-hexadecyl) -3-methylimidazolium, 1- (1-hexadecyl) -3- ethylimidazolium, 1- (1-hexadecyl) -3-butylimidazolium, 1- (1-hexadecyl) -3-octylimidazolium, 1,2-dimethylimidazolium, 1,2,3-trimethylimidazolium, 1-ethyl-2,3- dimethylimidazolium, 1- (1-butyl) -2,3-dimethylimidazolium, 1- (1-hexyl) -2,3-dimethylimidazolium, 1- (1-octyl) -2,3-dimethylimidazolium, 1, 4- Dimethylimidazolium, 1,3,4-trimethylimidazolium,

1, 4-dimethyl-3-ethylimidazolium, 3-butylimidazolium, 1,4-dimethyl-3-octylimidazolium, 1,4,5-trimethylimidazolium, 1,3,4,5-tetramethylimidazolium, 1, 4,5- Trimethyl 3-ethyl imidazolium, 1, 4,5-trimethyl-3-butyl imidazolium and 1, 4,5-trimethyl-3-octyl imidazolium

starts.

4. The method according to claim 3, characterized in that as ionic liquid 1, 3-dimethylimidazolium methylsulfate, 1, 3-dimethylimidazolium hydrogen sulfate, 1, 3-dimethylimidazolium dimethyl phosphate, 1-ethyl-3-methyl-imidazolium-methyl sulfate , i-ethyl-3-methylimidazolium hydrogensulfate, 1-ethyl-3-methylimidazolium thiocyanate, 1-ethyl-3-methylimidazolium acetate, 1-ethyl-3-methylimidazolium methanesulfonate, 1-ethyl-3-methylimidazolium diethyl phosphate, 1- (1-butyl) -3-methylimidazolium methylsulfate, 1- (1-butyl) -3-methylimidazolium hydrogensulfate, 1- (1-butyl) -3-methylimidazolium thiocyanate, 1- ( 1-butyl) -3-methylimidazolium acetate, 1- (1-butyl) -3-methylimidazolium methanesulfonate, 1- (1-dodecyl) -3-methylimidazolium methylsulfate, 1- (1-dodecyl) -3- methylimidazolium hydrogensulfate, 1- (1-tetradecyl) -3-methylimidazolium methylsulfate, 1- (1-tetradecyl) -3-methylimidazolium hydrogensulfate, 1- (1-hexadecyl) -3-methylimidazolium methylsulfate or 1- (1-hexadecyl) -3-methylimidazole ium-hydrogen sulfate used.

5. Process according to claims 1 to 4, characterized in that one uses a barrier liquid, which has a kinematic viscosity of 0.1 to 1000 mm ² / s under operating conditions.

6. Process according to claims 1 to 5, characterized in that one uses a barrier liquid, which in addition to the ionic liquid still water, ethylene glycol! and / or an oil.

7. Process according to claims 1 to 6, characterized in that one uses a barrier liquid, which to 50 to 100 wt .-% of the ionic

Liquid exists.

8. The method according to claim 7, characterized in that one uses a barrier liquid, which consists of 95 to 100 wt .-% of the ionic liquid.

9. Use of ionic liquids as part of the sealing liquid for mechanical seals for sealing rotating shafts.