EP4355482A1

EP4355482A1 - Epoxydation catalyst systems and process for preparing epoxides

Info

Publication number: EP4355482A1
Application number: EP22733410.9A
Authority: EP
Inventors: Matthias LEVEN; Jens Langanke
Original assignee: Covestro Deutschland AG
Current assignee: Covestro Deutschland AG
Priority date: 2021-06-18
Filing date: 2022-06-13
Publication date: 2024-04-24
Also published as: WO2022263343A1

Abstract

The invention relates to a first epoxydation catalyst system comprising a mixture of a metal salt of the metals chromium, manganese, molybdenum, lead and/or bismuth and a hydroxide as well as of a redox-active compound. The invention also relates to an additional second epoxydation catalyst system comprising a mixture of an additional metal salt, iodine and a hydroxide. Furthermore, the invention relates to a process for preparing epoxides comprising the oxidative reaction of an alkene in a reactor in the presence of the first epoxydation catalyst system or the second epoxydation catalyst system.

Description

Epoxidation catalyst systems and processes for preparing epoxides

The invention relates to a first epoxidation catalyst system comprising a mixture of a metal salt of the metals chromium, manganese, molybdenum, lead and/or bismuth and a hydroxide and a redox-active compound. A further object of the invention is a further, second epoxidation catalyst system comprising a mixture of a further metal salt, iodine and a hydroxide. Additionally, a process for preparing epoxides is comprised of oxidatively reacting an alkene in a reactor in the presence of the first epoxidation catalyst system or the second epoxidation catalyst system.

Numerous processes for the production of alkylene oxides, especially propylene oxide, have been described in the prior art, with the chlorohydrin process being of particular importance industrially, in which propene is treated with hypochlorous acid or chlorine and water to form an isomer mixture of 1-chloro-2-propanol and 2 -Chlorine-1-propanol is reacted, which is then reacted with milk of lime to form propylene oxide and calcium chloride. However, as a result of the formation of CaC12 salt load, there is a high level of waste water pollution or an additional recycling step and the integration into a chlor-alkali plant. This technology is assessed as detrimental in terms of carbon footprint and greenhouse gas emissions (Reduction of GHG Emissions in Propylene Oxide Production, Approved VCS Methodology VM0023 Version 1.0, 9 September 2013 Sectoral Scope 5, South Pole Carbon Asset Management Ltd.).

In addition, the production of propylene oxide by means of co-product-based processes (e.g. oxirane process) is relevant, in which ethylbenzene or isobutane is reacted in a 1st stage in the presence of oxygen to form the respective hydroperoxides, which are then reacted with propene to form propylene oxide and 1-Phenylethanol or tert-butanol can be implemented as further by-products. These by-products can then be further converted into styrene and isobutene or isobutane. However, in addition to the propylene oxide, a by-product is also formed, which has to be separated off and further processed in other plants. The co-product-based processes always require a sales market for the co-product and make the economics of such processes complex and prone to adverse effects. Thus, in addition to the technically demanding processes, there are also market risks, so that a techno-economic view of these processes paints a less than favorable overall picture. Especially since the demand and sales situation of both products, PO and the by-product, usually differ from region to region. This means that long-distance logistics are necessary, which have direct costs and other disadvantages, such as CO2/GHG emissions brings. The industrial MTBE process requires integration into a refinery operation in order to generate a maximum economic contribution.

The so-called HPPO process is also of industrial relevance, in which propylene is reacted with hydrogen peroxide to form propylene oxide and water. Compared to the large-scale production processes mentioned above, it is advantageous that there are no by-products or salt loads in the product. However, hydrogen peroxide has to be produced in an upstream, technically complex catalytic process. The process is considered technically demanding and is usually only operated at network sites with other H2O2 consumers.

The direct oxidation of propene to propylene oxide is still considered to be technically immature and according to the current state of the art there is no direct oxidation process that can be carried out economically on an industrial scale. In particular, the conduct of the reaction and especially the temperature control in gas-phase and molten salt processes are an unsolved challenge, but a high propene conversion in connection with a high PO selectivity is decisive for an efficient technical process. A number of by-products and by-products, such as methanol, acetaldehyde, carbon dioxide, ethylene and formaldehyde, occur in substantial amounts during direct oxidation (cf. D. Kahlich et al., Dow Germany in Ullmann's Encyclopedia of Industrial Chemistry, Chapter " Propylene Oxides”, Wiley VCH, 2012). For example, as current prior art documents for the aerobic oxidation of alkenes such as propene, US2018208569A1 and US2020346193A1 can be referred to. Only 54.5% or 60% epoxide selectivity is achieved at 8.6% or 5% conversion.

It was therefore an object of the present invention to provide a catalyst system for the direct production of epoxides, preferably propylene oxide, which, in the oxidative reaction of alkenes, preferably with oxygen or an oxygen-containing gas mixture, has an improved epoxide compared to systems known from the prior art - Turnover and improved product selectivity by reducing the formation of unwanted by-products and avoiding the formation of any by-products. This improved catalyst activity and selectivity should be reflected by the lowest possible activation energy E _A for the reaction sequence or the reaction mechanism of the hydroxylation of propene, ie the addition of propene to the catalyst system, and the reductive elimination of the propylene oxide formed from the catalyst system.

Surprisingly, it was found that the object of the invention is achieved by an epoxidation catalyst system (1), an epoxidation catalyst system (2) and a process for preparing epoxides comprising the oxidative reaction of an alkene in a reactor in the presence of the epoxidation catalyst system (1) or the epoxidation catalyst system (2) . The epoxidation catalyst system (1) comprises a) a mixture (1) or a reaction product (1) a-1) of a metal salt (A) of the metals chromium (Cr), manganese (Mn), molybdenum (Mo), lead (Pb) and/or bismuth (Bi) and a-2) a hydroxide (B) b) a redox-active compound (C).

According to the invention, one or more metal salts (A) of the metals chromium (Cr), manganese (Mn), molybdenum (Mo), lead (Pb) and/or bismuth (Bi) are used.

The following embodiments can be combined in any way, provided that the opposite does not result from the technical context and general specialist knowledge.

In one embodiment of the invention, the metal salt (A) is a nitrate, halide, tetrafluoroborate, sulfate, paratoluenesulfonate, methanesulfonate and/or triflate, preferably a chloride.

In a preferred embodiment of the invention, the metal salt (A) is one or more compounds and is selected from the group consisting of MoCE, MoOCE. MnCE, K ₂ MnCE, CrOCE, PbCU and BiCE.

In one embodiment of the invention, the hydroxide (B) is an organic hydroxide (B-1) and/or inorganic hydroxide (B-2).

In a preferred embodiment of the invention, the hydroxide (B) is an organic hydroxide (B-I) and the organic hydroxide (B-I) is one or more compound(s) and is selected from the group consisting of 3-(trifluoromethyl)phenyltrimethylammonium hydroxide, tetra- n-butylphosphonium hydroxide, choline hydroxide, benzyltrimethylammonium hydroxide,

tetraethylammonium hydroxide, tetra-n-propylammonium hydroxide, tetrabutylammonium hydroxide and tetramethylammonium hydroxide.

In a less preferred alternative embodiment of the invention, the hydroxide (B) is an inorganic hydroxide (B-2) and the inorganic hydroxide (B-2) is one or more compounds and is selected from the group consisting of Lithium hydroxide, sodium hydroxide, potassium hydroxide and their crown ether complexes, cesium hydroxide, calcium hydroxide, barium hydroxide, potassium aluminate, sodium aluminate, potassium aluminate and sodium zincate, preferably lithium hydroxide, sodium hydroxide and potassium hydroxide. In one embodiment of the invention, the redox-active compound (C) is one or more compound(s) and is selected from the group consisting of CuCF. Cu(BF )2. CuCl, VCE, VOCI3, NH4VO3, 1,4-Benzoquinone, 1,4-Naphtoquinone, SC2O5. Te02, Te02, SÜ203, SbiOs. CeCfi, Co(salen), Co(OAc)2, SnS0 ₄ , Fe(acac)3, Mo(acac)3, K ₂ Cr2O7, Mn(OAc)3, Ni(CF3C0 ₂ H) ₂ and Bi CI,.

In one embodiment of the invention, the calculated molar ratio of metal salt (A) to hydroxide groups of hydroxide (B) for epoxidation catalyst system (1) is from 1.000 moles to 1.000 moles to 6.000 moles to 1.000 moles.

In one embodiment of the invention, the calculated molar ratio of the metal salt (A) to the redox-active compound (C) for the epoxidation catalyst system (1) is from 0.100 mole to 1.000 mole to 10.000 mole to 1.000 mole.

In one embodiment of the invention, the calculated molar ratio of the hydroxide groups of the hydroxide (B) to that of the redox-active compound (C) for the epoxidation catalyst system (1) is from 0.100 mole to 1.000 mole to 50.000 mole to 1.000 mole.

In a less preferred embodiment of the invention, the epoxidation catalyst system (1) comprises the mixture (1) of the metal salt (A) and the hydroxide (B) in the calculated molar ratios described above.

In a preferred embodiment of the invention, the epoxidation catalyst system (1) comprises the reaction product (1) of the metal salt (A) and the hydroxide (B), the metal salt (A) and the hydroxide (B) being prepared using a preparation process known to those skilled in the art, such as, for example Solid state syntheses, precipitation or co-precipitation methods or as in situ salt metathesis is produced. For example, the reaction product (1) can be prepared by adding the organic hydroxide (B-1) and/or inorganic hydroxide (B-2) to a solution of the nitrate, halide, tetrafluoroborate, sulfate, paratoluenesulfonate, methanesulfonate and/or triflate, preferably a chloride of Metal salt (A) are synthesized in the above-described, calculated molar ratios, subsequent removal of the precipitate, drying and appropriate thermal treatment.

In a preferred embodiment of the invention, the reaction product (1) of the epoxidation catalyst system (1) has a structure of the formula (I), (II) and/or (III):

(Q RiR ₂ R3R4) ⁺ n ₊ om[M(A) ^m+ (Hal)n(OH) ₀ (S)p] im-no

(I) for the case m < n + o

[M(A) ^m+ (Hal)„(OH) ₀ (S)p] (P) for the case m = n + o

[M(A) ^m+ (Hal) _n (OH)o(S)p] ^(mno) [X] n+om (III) for the case m > n + o with

Q = nitrogen or phosphorus, preferably nitrogen

Ri, R ₂ , R ₃ , R ₄ independently selected from the group consisting of

(i) linear or branched alkyl groups containing 1 to 22 C atoms optionally substituted with heteroatoms and/or heteroatom containing substituents;

(ii) cycloaliphatic groups containing 3 to 22 C atoms with 1 to 3 bridging C atoms optionally substituted with heteroatoms and/or heteroatom containing substituents and/or

(iii) aryl groups containing 6 to 18 C atoms optionally substituted with 1 to 10 C atoms and/or optionally substituted with heteroatoms and/or heteroatom containing substituents; preferably R1, R2, R3 and R4 are independently selected from the group consisting of methyl, ethyl, isopropyl, n-propyl, isobutyl, t-Bu, n-butyl, phenyl, benzyl, (trifluoromethyl)phenyl

M(A) ^m+ = Mo ⁵⁺ , Mn ⁴⁺ , Cr ⁴⁺ , Pb ⁴⁺ , Bi ⁵⁺ preferably Mo ⁵⁺ ;

Hal=Cl, Br or G, preferably Cl or Br, particularly preferably Cl;

S = H2O, THF (tetrahydrofuran), or dioxane, bis(2-methoxyethyl)ether (diglyme), methoxyethanol, polyethylene glycols, pyridine, lutidine, 2,2'-bipyridine, acetonitrile, dimethyl sulfoxide, sulfolane, thiophene, preferably THF; n+o+p = 6n > 1; preferably n > 2; particularly preferably n = 2 o > 1; preferably o > 1; particularly preferably o=1; 2; 3 or 4 X = OTf,BF4 , Hai

In a particularly preferred embodiment of the invention, the reaction product (1) of the epoxidation catalyst system (1) is one or more compounds and is selected from the list consisting of [MO(Y)C1 ₂ (OH) ₂ (THF) ₂ ]C1, [Mn (IV)Cl(OH)3(THF) ₂ ], [Cr(VI)Cl ₂ (OH)2(THF) ₂ ]Cl2, [Pb(IV)Cl ₂ (OH) ₂ (THF) ₂ ] and [ Bi(V) _Cl2 (OH)3THF] . The mixture (1) or the reaction product (1) can be mixed with the redox-active compound (C) to form the epoxidation catalyst system (1) using the mixing methods known to those skilled in the art, such as stirring in solutions or suitable mixing of solids.

In one embodiment of the invention, the epoxidation catalyst system (1) further contains iodine (I ₂ ).

In a preferred embodiment of the invention, the iodine (U) is used in a calculated mole fraction of 1 mol % to 2000 mol %, based on the amount of the metal salt (A).

In one embodiment of the invention, the epoxidation catalyst system (1) is supported on a catalyst support (D) to form a supported epoxidation catalyst system (1).

In a preferred embodiment of the invention, the catalyst support (D) is one or more compound(s) and is selected from the group consisting of metal oxides, alkaline earth metal carbonates, silicates, silicon carbides, silicon oxy carbides, silicon nitrides, silicon oxynitrides and silicon dioxide, preferably aluminum oxide, aluminum dioxide, silica, Titanium dioxide, zirconia, calcium carbonate, phyllosilicates such as talc, kaolinites and pyrophyllites, and titanium dioxide.

According to the invention, the catalyst support can be in the form of a shaped body or a powder.

In one embodiment of the invention, the epoxidation catalyst system (1) is applied to the catalyst support (D) in a calculated mass fraction of 1.0% by weight to 30.0% by weight.

In one embodiment of the invention, the epoxidation catalyst system (1) is applied to the catalyst support (D) using the wet infiltration method (wet infiltration) or the incipient wetness method.

Another subject of the invention is an epoxidation catalyst system (2) comprising c) a mixture (2) or a reaction product (2) c-1) a metal salt (E), c-2) iodine (E) and c-3) a hydroxide (F) d) optionally a redox-active compound (G). In one embodiment of the invention, the metal salt (E) is a nitrate, halide, tetrafluoroborate, sulfate, paratoluenesulfonate, methanesulfonate and/or triflate, preferably a chloride.

In a preferred embodiment of the invention, the metal salt (E) is one or more compound(s) and is selected from the group consisting of NiCk, MnCk. PbCk. SnCk. CrCk, VC1 ₃ , MoCU, FeCk and RuCk.

In one embodiment of the invention, the hydroxide (F) is an organic hydroxide (F-1) and/or inorganic hydroxide (F-2).

In a preferred embodiment of the invention, the hydroxide (F) is an organic hydroxide (B-I) and the organic hydroxide (F-I) is one or more compound(s) and is selected from the group consisting of 3-(trifluoromethyl)phenyltrimethylammonium hydroxide, tetra- n-butylphosphonium hydroxide, choline hydroxide, benzyltrimethylammonium hydroxide,

In a less preferred alternative embodiment of the invention, the hydroxide (F) is an inorganic hydroxide (F-2) and the inorganic hydroxide (F-2) is one or more compound(s) and is selected from the group consisting of fithium hydroxide, Sodium hydroxide, potassium hydroxide and their crown ether complexes, cesium hydroxide, calcium hydroxide, barium hydroxide, potassium aluminate, sodium aluminate, potassium aluminate and sodium zincate, preferably fithium hydroxide, sodium hydroxide and potassium hydroxide.

In one embodiment of the invention, the redox-active compound (G) is one or more compound(s) and is selected from the group consisting of CuCk, Cu(BF4k, CuCl, VCk, VOCk, NH4VO3, 1,4-benzoquinones, 1,4 -Naphtoquinones, Se2Ck, TeCk, TeCk, Sb2C , Sb2Ck, CeCk, Co(salen), Co(OAc)2, SnSCk, Fe(acac)3, Mo(acac)3, K ₂ Cr2Ck, Mn(OAc)3, Ni(CF3CO2H ₎₂ _and BiCk.

In one embodiment of the invention, the calculated molar ratio of metal salt (E) to hydroxide groups of hydroxide (F) for epoxidation catalyst system (2) is from 1.000 moles to 1.000 moles to 6.000 moles to 1.000 moles.

In one embodiment of the invention, the calculated molar ratio of the metal salt (E) to the redox-active compound (G) for the epoxidation catalyst system (2) is from 0.100 mole to 1.000 mole to 10.000 mole to 1.000 mole.

In one embodiment of the invention, the calculated molar ratio of the hydroxide groups of the hydroxide (F) to that of the redox-active compound (G) for the epoxidation catalyst system (2) is from 0.100 mole to 1.000 mole to 50.000 mole to 1.000 mole. In a preferred embodiment of the invention, the iodine (E) is used in a calculated amount of from 1 mol % to 2000 mol %, based on the amount of the metal salt (E).

In a less preferred embodiment of the invention, the epoxidation catalyst system (2) comprises the mixture (2) of the metal salt (E), iodine and the hydroxide (F) in the calculated molar ratios described above.

In a preferred embodiment of the invention, the epoxidation catalyst system (2) comprises the reaction product (2) of the metal salt (E), iodine and the hydroxide (F), wherein the metal salt (E), the iodine and the hydroxide (F) with a for the Preparation methods known to those skilled in the art, such as solid-state syntheses, precipitation or co-precipitation methods, or as in situ salt metathesis. For example, by adding the organic hydroxide (F-1) and/or inorganic hydroxide (F-2) to a solution of the nitrate, halide, tetrafluoroborate, sulfate, paratoluenesulfonate, methanesulfonate and/or triflate, preferably a chloride of the metal salt (E ) are synthesized in the above-described, calculated molar ratios, subsequent separation of the precipitation product, drying and suitable thermal treatment.

In a preferred embodiment of the invention, the reaction product (2) of the epoxidation catalyst system (2) has a structure of the formula (IV), (V) and/or (VI):

(Q RiR ₂ R ₃ R ₄ ) ⁺ im-o-pi [M(E) ^m+ (Hal)n(OH)o(S)p] ^mn ° q T ₂ (IV) for the case m < n + O,

[M(E) ^m+ (Hal)n(OH) ₀ (S) _p ] qT ₂ (V) for the case m = n + o

[M(E) ^m+ (Hal)„(OH)o(S) _p ] ^mn ° q T ₂ [X] „ ₊₀ -m (VI) for the case m > n + o with

Q = nitrogen or phosphorus, preferably nitrogen

R 1 , R ₂ , R 1 . R ₄ independently selected from the group consisting of

(iii) aryl groups containing 6 to 18 C atoms optionally substituted with 1 to 10 C atoms and/or optionally substituted with heteroatoms and/or heteroatom containing substituents; preferably Ri, R ₂ , R and R ₄ independently selected from the group consisting of methyl, ethyl, isopropyl, n-propyl, isobutyl, t-Bu, n-butyl, phenyl, benzyl, (trifluoromethyl) phenyl particularly preferably methyl, benzyl and n-butyl; M(E) ^m+ = Ni ²⁺ , Mn ²⁺ , Pb ²⁺ , Sn ²⁺ , Cr' . V ³⁺ , Mo ⁴⁺ , Fe ²⁺ or Ru ³⁺ preferably Ni ²⁺ , Mn ²⁺ , Pb ²⁺ ,

Sn ²⁺ ;

Hal = CI , Br or G preferably CI or Br particularly preferably CI ,

S = H2O, THF (tetrahydrofuran), or dioxane, bis(2-methoxyethyl)ether (diglyme), methoxyethanol, polyethylene glycols, pyridine, futidine, 2,2'-bipyridine, acetonitrile, dimethyl sulfoxide, sulfolane, thiophene, preferably THF; n+o+p = 6; n > 1; preferably n > 2; particularly preferably n=2; o > 1; preferably o > 1; particularly preferably o=1; 2; 3 or 4;

X = OTf,BF4 , Hai ; q>1 preferably 1<q<2000 particularly preferably 1<q<10.

In a particularly preferred embodiment of the invention, the reaction product (2) of the epoxidation catalyst system (2) is one or more compounds and is selected from the list consisting of (Q RiR ₂ R ₃ R4)[Ni(II)Cl2(OH)(THF) 3] I _2, (Q RiR ₂ R3R4)[Mn(II)Cl ₂ (OH)(THF)3] I _2, (Q RiR ₂ R3R ₄ )[Pb(II)Cl ₂ (OH)(THF) ₃ ] I ₂ and (Q RiR ₂ R3R ₄ )[Sn(II)Cl ₂ (OH)(THF) ₃ ] I ₂ with Q = nitrogen and Ri, R ₂ , R3 and R4 independently selected from the group consisting of methyl, benzyl and n-butyl.

In one embodiment of the invention, the epoxidation catalyst system (2) is supported on a catalyst support (H) to form a supported epoxidation catalyst system (2).

In a preferred embodiment of the invention, the catalyst support (H) is one or more compound(s) and is selected from the group consisting of metal oxides, alkaline earth metal carbonates, silicates, silicon carbides, silicon oxycarbides, silicon nitrides, silicon oxynitrides and silicon dioxide, preferably aluminum oxide, aluminum dioxide, silica, Titanium dioxide, zirconia, calcium carbonate, phyllosilicates such as talc, kaolinites and pyrophyllites, and titanium dioxide.

In one embodiment of the invention, the epoxidation catalyst system (2) is applied to the catalyst support (H) in a calculated proportion by weight of from 1.0% by weight to 30.0% by weight.

In one embodiment of the invention, the epoxidation catalyst system (H) is applied to the catalyst support (H) using the wet infiltration method (wet infiltration) or the incipient wetness method. Another subject of the present invention is a process for preparing epoxides comprising the oxidative reaction of an alkene in a reactor in the presence of the epoxidation catalyst system (1) according to the invention or the epoxidation catalyst system according to the invention.

In one embodiment of the process according to the invention, the oxidative reaction takes place in the reactor in the presence of oxygen or an oxygen-containing gas mixture.

In addition to oxygen, the oxygen-containing gas mixture also includes dilution, carrier or inert gases such as hydrocarbons, noble gases, CO, CO 2 , N 2 .

In one embodiment of the inventive method, the oxygen or an oxygen-containing gas mixture are further additives such as water, CO, N-containing compounds such as hydrazine, ammonia (NH3), methylamine (MeMU), NOx, PH ₃ , SO ₂ and / or SO ₃ is added in amounts from 10 ppm to 500 ppm, preferably from 30 ppm to 300 ppm and particularly preferably from 50 ppm to 200 ppm. In addition, CO 2 can be added in a proportion of 0.01% by volume to 50% by volume, preferably from 0.1% by volume to 20% by volume, and particularly preferably from 1% by volume to 10% by volume. In addition, organic halides such as ethylene dichloride, ethyl chloride, vinyl chloride, methyl chloride and/or methylene chloride can be added in amounts from 10 ppm to 500 ppm, preferably from 50 ppm to 400 ppm, and particularly preferably from 100 ppm to 300 ppm.

In a preferred embodiment of the process according to the invention, the oxidative reaction takes place in the reactor in the presence of oxygen.

In one embodiment of the process according to the invention, the alkene is one or more compound(s) and is selected from the group consisting of ethene, propene, butene, 1-octene, butadiene, 1,4-butanediol diallyl ether, allyl chloride, allyl alcohol, styrene, cyclopentene, Cyclohexene, phenyl allyl ether, diallyl ether, n-butyl allyl ether, tert-butyl allyl ether, bisphenol A diallyl ether, resorcinol diallyl ether, triphenylolmethane triallyl ether, cyclohexane-1,2-dicarboxylic acid bis-

(allyl ester), tris-(2,3-propene) isocyanurate and mixtures of these alkenes, preferably ethene, propene and allyl chloride and particularly preferably propene.

The epoxide (alkylene oxide) according to the invention can be an epoxide having 2-45 carbon atoms. In one embodiment of the process according to the invention, the epoxide is selected from at least one compound from the group consisting of ethylene oxide, propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, 2-methyl-1,2-propylene oxide (isobutene oxide), 1,2 -pentylene oxide, 2,3-pentylene oxide, 2-methyl-1,2-butylene oxide, 3-methyl-1,2-butylene oxide, epoxides of C6-C22 a-olefins such as 1,2-hexylene oxide, 2,3-hexylene oxide , 3,4-hexylene oxide, 2-methyl-1,2-pentylene oxide, 4- Methyl-1,2-pentylene oxide, 2-ethyl-l,2-butylene oxide, 1,2-heptylene oxide, 1,2-octylene oxide, 1,2-nonylene oxide, 1,2-decylene oxide, 1,2-undecylene oxide, 1, 2-dodecylene oxide, 4-methyl- 1,2-pentylene oxide, cyclopentylene oxide, cyclohexylene oxide, cycloheptylene oxide, cyclooctylene oxide, styrene oxide, methylstyrene oxide, pinene oxide, allyl glycedyl ether, vinylcyclohexylene oxide, cyclooctadiene monoepoxide, cyclododecatriene monoepoxide, butadiene monoepoxide,

Isoprene monoepoxide, limonene oxide, 1,4-divinylbenzene monoepoxide, 1,3-divinylbenzene monoepoxide, glycidyl acrylate and glycidyl methacrylate, one or more times epoxidized fats as mono-, di- and triglycerides, epoxidized fatty acids, Cl-C24 esters of epoxidized fatty acids, epichlorohydrin, glycidol, and Glycidol derivatives such as glycidyl ethers of C1-C22 alkanols, glycidyl esters of C1-C22 alkanecarboxylic acids. Examples of derivatives of glycidol are phenyl glycidyl ether, cresyl glycidyl ether, methyl glycidyl ether, ethyl glycidyl ether and 2-ethylhexyl glycidyl ether.

In a preferred embodiment of the process, the epoxide is ethylene oxide, propylene oxide, 1,2-butylene oxide, 1,2-pentylene oxide, 1,2-hexylene oxide, 1,2-heptylene oxide and/or 1,2-octylene oxide. In a particularly preferred embodiment of the process, the epoxide is ethylene oxide and/or propylene oxide. In a most preferred embodiment of the process, the epoxide is propylene oxide.

In one embodiment of the process according to the invention, epoxides are prepared in the presence of a solvent.

In one embodiment of the method according to the invention, the solvent is one or more compound(s) and is selected from the group consisting of CO 2 , water, perfluoromethyldecalin, perfluorodecalin, perfluoroperhydrophenanthrene,

Perfluoro(butyltetrahydrofuran), tetrahydrofuran, 2-methyl-THF, acetic acid, acetonitrile, dimethyl sulfoxide, sulfolane, acetone, ethyl methyl ketone, dimethylformamide, dichloromethane, chloroform, tetrachloromethane, N-methyl-2-pyrrolidinone, methyl t-butyl ether (MTBE), Dimethyl Sulfide (DMSO), Hexamethylphosphoramide, Dichlorobenzene, 1,2-Dichloroethylene, 1,1,1,3,3,3-Hexafluoroisopropanol, Perfluoro-tert-butyl Alcohol, 1,1,2,3,3-Pentafluoropropane, 1-Bromo -2-chloro-1,1,2-trifluoroethane, 1,2-dichloro-1,1,2,3,3,3-hexafluoropropane, ethylene glycol, glycerine, and phenol.

In one embodiment of the process according to the invention, epoxides are prepared in the presence of a solvent, with the preparation being carried out at a temperature of from 20° C. to 200° C., preferably from 50° C. to 160° C. and particularly preferably from 100° C. to 150 °C In one embodiment of the process according to the invention, epoxides are prepared in the presence of a solvent, with the preparation taking place at a pressure of from 1 bara to 200 bara, preferably from 1 bara to 35 bara and particularly preferably from 1 bara to 28 bara.

In one embodiment of the process according to the invention, epoxides are prepared in the presence of a solvent, the preparation taking place over a period of 6 minutes to 48 hours, preferably 6 minutes to 24 hours and particularly preferably 6 minutes to 3 hours.

In one embodiment of the process according to the invention, epoxides are prepared in the presence of a solvent, the molar ratio of the alkene to oxygen being from 1:100 to 100:1, preferably from 1:30 to 30:1.

In an alternative embodiment of the process according to the invention, epoxides are prepared in the absence of a solvent.

According to the invention, a solvent-free process means that solvent residues, for example as a result of the preparation of the starting materials, are present in an amount of up to 10% by volume, preferably up to 5% by volume and particularly preferably up to 2% by volume, based on the amount of propene used could be.

In one embodiment of the process according to the invention, epoxides are prepared in the absence of a solvent, the preparation being carried out using the supported epoxidation catalyst system (1) according to the invention or the supported epoxidation catalyst system (2) according to the invention.

In one embodiment of the process according to the invention, epoxides are prepared in the absence of a solvent, with the preparation being carried out at a temperature of from 20.degree. C. to 500.degree. C., preferably from 50.degree. C. to 400.degree. C. and particularly preferably from 50.degree. C. to 250.degree he follows.

In one embodiment of the process according to the invention, epoxides are prepared in the absence of a solvent, with the preparation taking place at a pressure of from 1 bara to 200 bara, preferably from 2 bara to 100 bara and particularly preferably from 2 bara to 50 bara.

In one embodiment of the process according to the invention, epoxides are produced in the absence of a solvent, the production being carried out with a space velocity (English Gas Houmly Space Velocity GHSV) as the quotient of the volume flow of the reactant gases used to the catalyst volume of 100 h-1 to 10000 h-1, preferably from 200 h-1 to 5000 h-1 and particularly preferably from 500 h-1 to 2000 h-1. In the case of a supported catalyst and/or a catalyst diluted by means of an inert diluent (for example aluminum oxide, silica, silicon carbide), the catalyst volume corresponds to that of the supported catalyst epoxidation catalyst system (1) or (2) and/or the sum of the catalyst and diluent volume.

In one embodiment of the process according to the invention, epoxides are prepared in the absence of a solvent, the molar ratio of the alkene to oxygen being from 1.0:0.1 to 2:1, preferably from 1:0.5 to 2:1 and particularly preferably from is 1:0.8 to 2:1.

In one embodiment of the process according to the invention, the alkene is metered into the reactor continuously or in stages, preferably continuously.

In one embodiment of the process according to the invention, oxygen or the oxygen-containing gas mixture is metered into the reactor continuously or in stages, preferably continuously.

In one embodiment of the process according to the invention, the alkene and the oxygen or the oxygen-containing gas mixture are metered into the reactor continuously or in stages, preferably continuously.

In a preferred embodiment of the process according to the invention, the epoxide is removed from the reactor continuously or in stages, preferably continuously.

In a preferred embodiment of the process according to the invention, the epoxidation catalyst system (1) is metered continuously or stepwise, preferably continuously, into the reactor.

The process according to the invention can be carried out in a batch process, in a semi-batch process or in a continuous procedure, reactor types known to those skilled in the art being used for this purpose. Thus, epoxides can be prepared continuously by the oxidative reaction of alkenes in a continuous stirred tank reactor (CSTR) or a single- or double-column bubble reactor in the liquid phase in the presence of a solvent. The continuous production of epoxides in the gas phase in the absence of a solvent can be carried out by means of a continuous gas phase reactor, such as a fixed bed reactor, also using ceramic packing materials.

In a preferred embodiment of the process according to the invention, the epoxidation catalyst system (1) and/or epoxidation catalyst system (2) is used in a calculated amount of 10 ppm to 500,000 ppm, preferably 100 ppm to 200,000 ppm and particularly preferably 1000 ppm to 150,000 ppm by mass all reactants involved and optional solvents and possible other auxiliaries used. In a first embodiment, the invention relates to an epoxidation catalyst system (1) comprising a) a mixture, preferably a reaction product a-1) of a metal salt (A) of the metals chromium (Cr), manganese (Mn), molybdenum (Mo), lead (Pb) and/or bismuth (Bi) and a-2) a hydroxide (B) b) a redox-active compound (C).

In a second embodiment, the invention relates to an epoxidation catalyst system (1) according to the first embodiment, wherein the metal salt (A) is a nitrate, halide, tetrafluoroborate, sulfate, paratoluenesulfonate, methanesulfonate and/or triflate, preferably a chloride.

In a third embodiment, the invention relates to an epoxidation catalyst system (1) according to the first or second embodiment, wherein the metal salt (A) is one or more compounds and is selected from the group consisting of MoCE, MoOCE. MnCE, K ₂ MnCE, CrOCE, PbCU and BiCE.

In a fourth embodiment, the invention relates to an epoxidation catalyst system (1) according to any one of the first to third embodiments, wherein the hydroxide (B) is an organic hydroxide (B-1) and/or inorganic hydroxide (B-2).

In a fifth embodiment, the invention relates to an epoxidation catalyst system (1) according to the fourth embodiment, wherein the hydroxide (B) is an organic hydroxide (B-l) and the organic hydroxide (B-l) is one or more compound(s) and is selected from The group consisting of 3-(trifluoromethyl)phenyltrimethylammonium hydroxide, tetra-n-butylphosphonium hydroxide, choline hydroxide, benzyltrimethylammonium hydroxide, tetraethylammonium hydroxide, tetra-n-propylammonium hydroxide, tetrabutylammonium hydroxide and tetramethylammonium hydroxide.

In a sixth embodiment, the invention relates to an epoxidation catalyst system (1) according to the fourth embodiment, wherein the hydroxide (B) is an inorganic hydroxide (B-2) and the inorganic hydroxide (B-2) is one or more compound(s) and is selected from the group consisting of lithium hydroxide, sodium hydroxide, potassium hydroxide and their crown ether complexes, cesium hydroxide, calcium hydroxide, barium hydroxide, potassium aluminates, Sodium aluminate, potassium aluminate and sodium zincate, preferably lithium hydroxide, sodium hydroxide and potassium hydroxide.

In a seventh embodiment, the invention relates to an epoxidation catalyst system (1) according to one of the first to sixth embodiments, wherein the redox-active compound (C) is one or more compound(s) and is selected from the group consisting of copper dichloride, CuCl 2. Cu( BF4)2, CuCl, VCh. VOCE, NH4VO3, 1,4-Benzoquinone, 1,4-Naphtoquinone, Se20s, Te02, TeCh, Sb2Ü3, Sb20s, CeCL, Co(salen), Co(OAc)2, SnS04, Fe(acac)3, Mo(acac ) ₃ , K ₂ Cr 2 O ₇ , Mn(OAc) ₃ , Ni(CF ₃ CO 2 H) ₂ and BiCl ₃ .

In an eighth embodiment, the invention relates to an epoxidation catalyst system (1) according to one of the first to seventh embodiments, wherein the calculated molar ratio of the metal salt (A) to the hydroxide groups of the hydroxide (B) is from 1.000 mol to 1.000 mol to 6.000 mol to 1.000 mol .

In a ninth embodiment, the invention relates to an epoxidation catalyst system (1) according to one of the first to eighth embodiments, wherein the calculated molar ratio of the metal salt (A) to the redox-active compound (C) is from 0.100 mol to 1.000 mol to 10.000 mol to 1.000 mol.

In a tenth embodiment, the invention relates to an epoxidation catalyst system (1) according to one of the first to ninth embodiments, the calculated molar ratio of the hydroxide groups of the hydroxide (B) to that of the redox-active compound (C) of 0.100 mol to 1.000 mol to 50.000 mol to 1,000 moles.

In an eleventh embodiment, the invention relates to an epoxidation catalyst system (1) according to one of the first to tenth embodiments, the epoxidation catalyst system (1) further comprising iodine (I2).

In a twelfth embodiment, the invention relates to an epoxidation catalyst system (1) according to the eleventh embodiment, the iodine (I2) being used in a calculated mole fraction of 1 mol % to 2000 mol % based on the amount of the metal salt (A).

In a thirteenth embodiment, the invention relates to an epoxidation catalyst system (1) according to one of the first to twelfth embodiments, the epoxidation catalyst system (1) being applied to a catalyst support (D) to form a supported epoxidation catalyst system (1).

In a fourteenth embodiment, the invention relates to an epoxidation catalyst system (1) according to the thirteenth embodiment, wherein the catalyst support (D) is one or more compound(s) and is selected from the group consisting of metal oxides, alkaline earth metal carbonates, silicates, silicon carbides, silicon oxy carbides, silicon nitrides,

silicon oxynitrides and silica, preferably alumina alumina, silica, titania, zirconia, calcium carbonate, phyllosilicates such as talc, kaolinites and pyrophyllites and titania.

In a fifteenth embodiment, the invention relates to an epoxidation catalyst system (1) according to the thirteenth or fourteenth embodiment, the epoxidation catalyst system (1) being applied to the catalyst support in a calculated mass fraction of 1.0% by weight to 30.0% by weight (D) is applied.

In a sixteenth embodiment, the invention features an epoxidation catalyst system

(1) according to any one of the thirteenth to fifteenth embodiments, wherein the

The epoxidation catalyst system (1) is applied to the catalyst support (D) using the wet infiltration method (wet infiltration) or the incipient wetness method.

In a seventeenth embodiment, the invention relates to an epoxidation catalyst system (2) comprising c) a mixture, preferably a reaction product of c-1) a metal salt (E), c-2) iodine (E) and c-3) a hydroxide (F) d) optionally a redox active compound (G).

In an eighteenth embodiment, the invention relates to an epoxidation catalyst system (2) according to the seventeenth embodiment, wherein the metal salt (E) is a nitrate, halide, tetrafluoroborate, sulfate, paratoluenesulfonate, methanesulfonate and/or triflate, preferably a chloride.

In a nineteenth embodiment, the invention features an epoxidation catalyst system

(2) according to the seventeenth or eighteenth embodiment, wherein the metal salt (E) is one or more compounds and is selected from the group consisting of NiCk, MnCE. PbCE. SnCl ₂ , CrCk, VC1 ₃ , MoCU, FeCk and RuCk.

In a twentieth embodiment, the invention relates to an epoxidation catalyst system (2) according to one of the seventeenth to nineteenth embodiments, where the hydroxide (F) is an organic hydroxide (F1) and/or inorganic hydroxide (F-2). In a twenty-first embodiment, the invention relates to an epoxidation catalyst system (2) according to the twentieth embodiment, wherein the hydroxide (F) is an organic hydroxide (BI) and the organic hydroxide (FI) is one or more compound(s) and is selected from the group consisting of 3-(trifluoromethyl)phenyltrimethylammonium hydroxide, tetra-n-butylphosphonium hydroxide, choline hydroxide, benzyltrimethylammonium hydroxide, tetraethylammonium hydroxide, tetra-n-propylammonium hydroxide, tetrabutylammonium hydroxide and tetramethylammonium hydroxide.

In a twenty-second embodiment, the invention relates to an epoxidation catalyst system (2) according to the twenty-first embodiment, wherein the hydroxide (F) is an inorganic hydroxide (F-2) and the inorganic hydroxide (F-2) is one or more compound(s) and is selected from the group consisting of lithium hydroxide, sodium hydroxide, potassium hydroxide and their crown ether complexes, cesium hydroxide, calcium hydroxide, barium hydroxide, potassium aluminate, sodium aluminate, potassium aluminate and sodium zincate, preferably lithium hydroxide, sodium hydroxide and potassium hydroxide.

In a twenty-third embodiment, the invention relates to a

The epoxidation catalyst system (2) according to any one of the seventeenth to twenty-second

Embodiment wherein the redox active compound (G) is present and the redox active compound (G) is one or more compounds and is selected from the group consisting of CuCE. CU(BF4)2, CuCl, VC'k ^VOCE , NH4VO3, 1,4-Benzoquinone, 1,4-Naphtoquinone, SC2O5. Te02, Te02, Sb203, Sb20s, CeCE, Co(salen), Co(OAc)2, SnS04, Fe(acac)3, Mo(acac)3, K2Cr207, Mn(OAc) ₃ , Ni(CF ₃ C02H) ₂ and BiCE.

In a twenty-fourth embodiment, the invention relates to a

The epoxidation catalyst system (2) according to any one of the seventeenth to twenty-third

Embodiment wherein the calculated molar ratio of the metal salt (E) to the hydroxide groups of the hydroxide (B) is from 1.000 moles to 1.000 moles to 6.000 moles to 1.000 moles.

In a twenty-fifth embodiment, the invention relates to a

The epoxidation catalyst system (2) according to any one of the seventeenth to twenty-fourth

Embodiment wherein the calculated molar ratio of the metal salt (E) to the redox-active compound (G) is from 0.100 mole to 1.000 mole to 10.000 mole to 1.000 mole.

In a twenty-sixth embodiment, the invention relates to a

The epoxidation catalyst system (2) according to any one of the seventeenth to twenty-fifth

Embodiment, wherein the calculated molar ratio of the hydroxide groups of hydroxide (F) to that of the redox-active compound (G) is from 0.100 mol to 1.000 mol to 50.000 mol to 1.000 mol.

In a twenty-seventh embodiment, the invention relates to a

The epoxidation catalyst system (2) according to any one of the seventeenth to twenty-sixth embodiments, wherein the iodine (12) is used in a calculated mole fraction of 1 mol% to 2000 mol% based on the amount of the metal salt (A).

In a twenty-eighth embodiment, the invention relates to a

The epoxidation catalyst system (2) according to any one of the seventeenth to twenty-seventh embodiments, wherein the epoxidation catalyst system (2) is supported on a catalyst support (H) to form a supported epoxidation catalyst system (2).

In a twenty-ninth embodiment, the invention relates to a

The epoxidation catalyst system (2) according to the twenty-eighth embodiment, wherein the catalyst support (H) is one or more compound(s) and is selected from the group consisting of metal oxides, alkaline earth carbonates, silicates, silicon carbides, silicon oxy carbides, silicon nitrides, silicon oxynitrides and silicon dioxide, preferably alumina aluminum dioxide , silica, titanium dioxide, zirconia, calcium carbonate, phyllosilicates such as talc, kaolinites and pyrophyllites, and titanium dioxide.

In a thirtieth embodiment, the invention relates to an epoxidation catalyst system (2) according to the twenty-eighth or twenty-ninth embodiment, wherein the epoxidation catalyst system (2) is applied to the catalyst support in a calculated mass fraction of from 1.0% to 30.0% by weight (H) is applied.

In a thirty-first embodiment, the invention relates to an epoxidation catalyst system (2) according to one of the twenty-eighth to thirtieth embodiment, wherein the epoxidation catalyst system (2) is applied to the catalyst support (H) using the wet infiltration method (wet infiltration) or the incipient wetness method.

In a thirty-second embodiment, the invention relates to a process for preparing epoxides comprising the oxidative reaction of an alkene in a reactor in the presence of the epoxidation catalyst system (1) according to one of the first to sixteenth embodiments or the epoxidation catalyst system (2) according to one of the seventeenth to thirty-first embodiments. In a thirty-third embodiment, the invention relates to a method according to the thirty-second embodiment, in which the oxidative reaction in the reactor takes place in the presence of oxygen or an oxygen-containing gas mixture.

In a thirty-fourth embodiment, the invention relates to a process according to the thirty-second or thirty-third embodiment, wherein the alkene is one or more compound(s) and is selected from the group consisting of ethene, propene, butene, 1-octene, butadiene, 1,4 -Butanediol diallyl ether, allyl chloride, allyl alcohol, styrene, cyclopentene, cyclohexene, phenyl allyl ether, diallyl ether, n-butyl allyl ether, tert-butyl allyl ether, bisphenol-A diallyl ether, resorcinol diallyl ether, triphenylolmethane triallyl ether, cyclohexane-1,2- dicarboxylic acid bis(allyl ester), isocyanuric acid tris(prop-2,3-ene) ester and mixtures of these alkenes, preferably ethene, propene and allyl chloride and particularly preferably propene.

In a thirty-fifth embodiment, the invention relates to a method according to one of the thirty-second to thirty-fourth embodiments, the production being carried out in the presence of a solvent.

In a thirty-sixth embodiment, the invention relates to a method according to one of the thirty-fifth embodiment, wherein the solvent is one or more compound(s) and is selected from the group consisting of CO 2 , water, perfluoromethyldecalin, perfluorodecalin, perfluoroperhydrophenanthrene,

In a thirty-seventh embodiment, the invention relates to a method according to the thirty-fifth or thirty-sixth embodiment, wherein the production takes place at a temperature of 20°C to 200°C, preferably of 50°C to 160°C and particularly preferably of 100°C to 150°C he follows.

In a thirty-eighth embodiment, the invention relates to a method according to one of the thirty-fifth to thirty-seventh embodiments, the production taking place at a pressure of 1 bara to 200 bara, preferably 1 bara to 35 bara and particularly preferably 1 bara to 28 bara. In a thirty-ninth embodiment, the invention relates to a method according to one of the thirty-fifth to thirty-eighth embodiments, the production taking place in a period of 6 minutes to 48 hours, preferably 6 minutes to 24 hours and particularly preferably 6 minutes to 3 hours.

In a fortieth embodiment, the invention relates to a process of one of the thirty-fifth to thirty-ninth embodiments, wherein the molar ratio of the alkene to the oxygen is from 1:100 to 100:1, preferably from 1:30 to 30:1.

In a forty-first embodiment, the invention relates to a method according to one of the thirty-second to thirty-fourth embodiments, wherein the preparation takes place in the absence of a solvent.

In a forty-second embodiment, the invention relates to a method according to the forty-first embodiment, wherein the preparation using the using the supported epoxidation catalyst system (1) according to one of the thirteenth to sixteenth embodiment or a supported epoxidation catalyst system (2) according to one of the twenty-eighth to thirty-first embodiment.

In a forty-third embodiment, the invention relates to a method according to the forty-first or forty-second embodiment, wherein the production takes place at a temperature of 20°C to 500°C, preferably of 50°C to 400°C and particularly preferably of 50°C to 250°C he follows.

In a forty-fourth embodiment, the invention relates to a method according to one of the forty-first to forty-third embodiments, the production taking place at a pressure of 1 bara to 200 bara, preferably 2 bara to 100 bara and particularly preferably 2 bara to 50 bara.

In a forty-fifth embodiment, the invention relates to a method according to one of the forty-first to forty-fourth embodiments, wherein the production takes place at a space velocity of 100 h-1 to 10000 h-1, preferably from 200 h-1 to 5000 h-1 and particularly preferably from 500 h-1 to 2000 h-1.

In a forty-sixth embodiment, the invention relates to a method according to one of the forty-first to forty-fifth embodiments, wherein the molar ratio of the alkene to the oxygen is from 1.0:0.1 to 2.0:1.0, preferably from 1.0:0.5 to is 2.0:1.0 and more preferably from 1.0:0.8 to 2.0:1.0. In a forty-seventh embodiment, the invention relates to a process according to one of the thirty-second to forty-sixth embodiment, wherein the alkene is metered into the reactor continuously or in stages, preferably continuously.

In a forty-eighth embodiment, the invention relates to a method according to one of the thirty-third to forty-seventh embodiment, wherein the oxygen or the oxygen-containing gas mixture is metered into the reactor continuously or in stages, preferably continuously.

In a forty-ninth embodiment, the invention relates to a process according to one of the thirty-third to forty-eighth embodiments, the alkene and the oxygen or the oxygen-containing gas mixture being metered continuously or in stages, preferably continuously, into the reactor.

In a fiftieth embodiment, the invention relates to a process according to one of the forty-seventh to forty-ninth embodiments, wherein the epoxide is removed from the reactor continuously or in stages, preferably continuously. In a fifty-first embodiment, the invention relates to a process of one of the forty-seventh to fiftieth embodiment, wherein the epoxidation catalyst system (1) and/or epoxidation catalyst system (2) is metered continuously or stepwise, preferably continuously, into the reactor.

In a fifty-second embodiment, the invention relates to a method according to one of the thirty-second to fifty-first embodiment, wherein the

Epoxidation catalyst system (1) and/or epoxidation catalyst system (2) in a calculated amount of 10 ppm to 500,000 ppm, preferably 100 ppm to 200,000 ppm and particularly preferably 1000 ppm to 150,000 ppm, based on the mass of all reactants involved and optionally solvents and possible others Auxiliaries is used.

examples

Raw materials used:

Metal chlorides and metal oxides: All metal salts used are obtained directly from commercial sources and used without further processing as precursors for the active catalysts in the corresponding reactions:

Molybdenum (V) chloride from the manufacturer Sigma Aldrich Corporation in a purity of 95%. Manganese (II) chloride from the manufacturer Sigma Aldrich Corporation in a purity of 99%. Chromium (VI) oxychloride from the manufacturer Sigma Aldrich Corporation in a purity of 99%. Lead (II) chloride from the manufacturer Sigma Aldrich Corporation with a purity of 98%. Bismuth (III) chloride from the manufacturer Sigma Aldrich Corporation in a purity of 98%. Copper (II) chloride from the manufacturer Sigma Aldrich Corporation in a purity of 97%. Nickel(II) chloride from the manufacturer Sigma Aldrich Corporation with a purity of 98%. Tin(II) chloride from the manufacturer Sigma Aldrich Corporation with a purity of 98%. Molybdenum(VI) oxychloride was based on Vitzthumecker et al. in month Chem. 148, 629-633 (2017).

Elemental iodine, Triton B and all solvents used were also used in the reaction without further processing:

Iodine from the manufacturer Sigma Aldrich Corporation in a purity of 99.8%.

Tetrahydrofuran (THF) from the manufacturer Sigma Aldrich Corporation with a purity of 99.9% (inhibitor-free).

Benzyltrimethylammonium hydroxide (Triton B) from Sigma Aldrich Corporation as a 40% solution in methanol.

Propylene was obtained from Sigma Aldrich Corporation at 99.9% purity and used as received.

The chemicals are used for the synthesis without further purification.

Gas chromatography analysis

The gas chromatographic analysis (GC for short) of liquid and gas samples was based on "Determine Impurities in High-Purity Propylene Oxide with Agilent J&W PoraBOND U" by Dianli Ma, Ningbo ZRCC Lyondell Chemical Co., Ltd Zhejiang, China, and Yun Zou , Hua Wu, Agilent Technologies, Ine. carried out. Conversions of propenes, yields of propylene oxides and selectivities were determined on the basis of GC.

simulation method

All quantum mechanical calculations were carried out with the program package TURBOMOLE Version 7.4.1 from Cosmologic GmbH & Co. KG. The density functional theory method used was the TPSS density functional, executed as an unrestricted-DFT for spin contamination of open-shell systems, with a def2-SVP basis set, as implemented by default in the Turbomole program package. The energies obtained were refined using the described DFT method and a basis set of quality def2-TZVP.

Transition states were calculated using gradient based Monte Carlo as described in application WO 2020/079094A2.

Preparation of the epoxidation catalyst system (1).

The epoxidation catalyst systems listed in Tables 1 and 2 were prepared and used as described in the general experimental specifications.

General working instructions for the in situ synthesis of the epoxidation catalyst system (1)

200 mL of tetrahydrofuran were placed under inert conditions in a reaction vessel with a stirrer and protective gas aeration. In each experiment, 0.020 mol of the metal (oxy)chloride of the corresponding oxidation state (see Table 1, 1-5) and 0.020 mol of CuCh as the redox-active compound (C) were added to the solvent under protective gas countercurrent. With vigorous stirring, N-benzyltrimethylammonium hydroxide (trade name Triton B) was stirred in until a liquid sample taken in contact with a pH test strip moistened with water showed a pH value of 10-11.

The suspension produced in this way was used for the oxidation of propene without further purification. Table 1: Overview of the epoxidation catalyst systems (1) used for the oxidative conversion of propene

(Ref.) Comparative Example Preparation of Epoxidation Catalyst System (2).

General Procedure for the In Situ Synthesis of the Epoxidation Catalyst System (2)

A mixture of 180 mL of tetrahydrofuran and 20 mL of water was placed under inert conditions in a reaction vessel with a stirrer and inert gas aeration. 0.020 mol of the metal (oxy)chloride of the corresponding oxidation state (see Table 2, 9-12) and 0.040 mol (5.1 g) of elementary iodine were added to the solvent mixture under protective gas countercurrent. With vigorous stirring, N-benzyltrimethylammonium hydroxide (trade name Triton B) was stirred in until a liquid sample taken in contact with a pH test strip moistened with water showed a pH value of 10-11. The suspension produced in this way was used for the oxidation of propene without further purification. Table 2: Overview of the epoxidation catalyst systems (2) used for the oxidative conversion of propene

_R2 = _R3 = _R4 =methyl

Simulation results for the process of producing propylene oxide by oxidation of propene in the presence of the epoxidation catalyst system (1).

In the following, the activation energies for the catalytic reactions were calculated using quantum chemical simulations. For this purpose, a structure according to the transition states A TI - B T2 was drawn (Figure 1). The bonds in bold were set to an atomic distance of 1.90 Å (190 pm) each, in the case of A T2 to 1.30 Å, and the resulting structures were translated into Cartesian coordinates. The atomic indices in the Cartesian coordinate set of the bonds drawn in bold in Figure 3 were set as a function space in the gradient-based Monte Carlo program and the Monte Carlo procedure was carried out until the corresponding transition states A TI - B T2 were obtained. The Cartesian coordinates of the structures A TI - B T2 obtained in this way were then manipulated in order to obtain the associated educt-catalyst complexes or the associated catalyst-product complexes. For this purpose, one of the bonds drawn in bold (Figure 3) was i) lengthened and ii) shortened by DC=0.20 Å (20 pm). The structures i) and ii) obtained in this way were brought into the form of Cartesian coordinates, subjected to geometry optimization using the DFT method described, and the geometries obtained were used to calculate the activation energies. The bonds selected in each case are compiled in Table 3. Table 3: Selection of the bonds for manipulation to obtain the equilibrium structures.

Fig. 1: Three-step reaction mechanism for the oxidative hydroxylation of propene with hydroxide under metal catalysis.

The three-step mechanism described in Figure 1 was calculated by quantum chemical simulation for different catalysts and the activation energies were determined from the respective reaction sequence. The obtained activation energy estimate was used to evaluate different metal compounds as potential catalysts for the oxidative hydroxylation. The results of the simulations are summarized in Table 4. Tab. 4: Comparison of the quantum chemically simulated activation energies for the oxidative conversion of propene with different epoxidation catalyst systems (1).

(Comp.) Comparative Example; Q(l) = benzyltrimethylammonium with Q = N; R 1 =benzyl, R ₂ =R ₃ =R ₄ =methyl ^a) Assumption that the THF ligand is at least partially displaced by propene from the complex epoxidation catalyst system (1) before the oxidative conversion.

The results summarized in Table 4 show that in particular the activation energies of the hydroxylation of the propene and the reductive elimination of the propylene oxide formed depend strongly on the particular metal functioning as a catalyst. As a result, the possible selection of the investigated metal compounds as catalysts for the oxidative hydroxylation is limited to certain metals. Suitable metals are, above all, Mo(V), Mn(IV), Cr(VI), Bi(V) and Pb(IV). Simulation results for the process of producing propylene oxide by oxidation of propene in the presence of the epoxidation catalyst system (2).

In a further embodiment B of the process, the epoxidation catalyst system (2) consisting of the metal salt (E), elemental iodine and the hydroxide (F) is used. This mixture (2) is loaded with propene, with the hydroxide first being added to the double bond of the propene. In a second step, iodine is then inserted into the metal-carbon bond, releasing an iodohydrin. This decomposes in a slightly basic environment to form propylene oxide and iodide, which is oxidized back to elemental iodine by supplying oxygen. The metal catalyst ensures controlled addition of hydroxide and iodine to form intermediate iodohydrin without the formation of predominantly useless 1,2-diiodoalkanes. Compared to the known chlorohydroxylation, the iodine can be used here in catalytic or substoichiometric amounts. The oxidation can thus take place directly with oxygen.

For this purpose, quantum chemical simulations were carried out to identify suitable metal catalysts.

Tab. 5: Comparison of the quantum chemically simulated activation energies for the iodohydroxylation of propene with different metal catalysts.

(Comp.) Comparative Example; Q(l) = benzyltrimethylammonium with Q = N; Ri=benzyl, R2=R3=R4=methyl; ^a) Assumption that the THF ligand is at least partially displaced by propene and iodine before the oxidative conversion from the complex epoxidation catalyst system (1).

The simulation results summarized in Table 5 show that the activation energy of the iodine insertion essentially depends on the metal catalysts used. Mn(II), Sn(II) and Pb(II) in particular, but also Ni(II) are thereby identified as suitable catalysts for the reaction.

Fig. 2: Two-step reaction mechanism for the metal-catalyzed iodohydroxylation of propene.

Fig. 3: Input geometries for the quantum chemical calculations of the transition states of the catalyzed oxidative hydroxylation A and iodohydroxylation B.

B T1 B T2

General experimental procedure for the process for preparing propylene oxide by oxidizing propene in the presence of the epoxidation catalyst system (1) in a discontinuous stirred tank.

200 mL of tetrahydrofuran were placed under inert conditions in a pressure-resistant IL reactor with stirrer, overpressure protection, pressure sensor, riser pipe for removing liquid and gassing and degassing lines. In each experiment, 0.020 mol of the metal chloride of the appropriate oxidation state (see Table 1, 1-5) and 0.020 mol of CuCl2 were added to the solvent under protective gas countercurrent. With vigorous stirring, N-benzyltrimethylammonium hydroxide (trade name Triton B) stirred until a liquid sample taken in contact with a water-moist pH test strip showed a pH value of 10-11. The reaction vessel was then charged with 0.400 mol of propene (about 11 bar). The internal temperature of the reactor was regulated to 120° C. and oxygen was slowly forced in until a substance amount of 0.200 mol of oxygen was reached. The oxygen was added in such a way that the additional pressure rise was never more than 2 bar. The progress of the reaction and the end point were determined based on the pressure profile and/or by taking liquid and gas samples and analyzing them by GC. After the reaction had ended, the reactor was cooled to 40° C. and then let down and the reaction product, propylene oxide, was distilled off via the degassing line into a cooled receiver.

The yield of propylene oxide was 23.2 g for all five runs.

General experimental procedure for the process for preparing propylene oxide by oxidizing propene in the presence of the epoxidation catalyst system (2) in a discontinuous stirred tank.

A mixture of 180 mL of tetrahydrofuran and 20 mL of water was placed under inert conditions in a pressure-resistant IL reactor with a stirrer, overpressure protection, pressure sensor, riser pipe for taking off liquid and gassing and degassing lines. 0.020 mol of the metal chloride of the corresponding oxidation state (see Table 2, 9-12) and 0.040 mol (5.1 g) of elementary iodine were added to the solvent mixture under protective gas countercurrent. With vigorous stirring, N-benzyltrimethylammonium hydroxide (trade name Triton B) was stirred in until a liquid sample taken in contact with a pH test strip moistened with water showed a pH value of 10-11. The reaction vessel was then charged with 0.400 mol of propene (about 11 bar). The internal temperature of the reactor was regulated to 120° C. and oxygen was slowly forced in until a substance amount of 0.200 mol of oxygen was reached. The oxygen was added in such a way that the additional pressure rise was never more than 2 bar. The progress of the reaction and the end point of the reaction were determined based on the pressure profile and/or by taking liquid and gas samples and analyzing them by GC. After the reaction had ended, the reactor was cooled to 40° C. and then let down and the reaction product, propylene oxide, was distilled off via the degassing line into a cooled receiver.

The yield of propylene oxide was 23.2 g for all four experiments. General experimental procedure for the process for the production of propylene oxide by the oxidation of propene in the presence of the epoxidation catalyst system (1) in a continuous single-bubble column reactor.

3500 mL tetrahydrofuran were placed under inert conditions in a pressure-resistant bubble column (15 cm diameter) with gassing frit, overpressure protection, pressure sensor, upper and lower liquid outlet, upper addition point for solids and inlet and outlet lines for gases. In each experiment, 0.350 mol of the metal chloride of the corresponding oxidation state (see Table 1, 1-5) and 0.350 mol of CuCl2 were added to the solvent under protective gas countercurrent. While gassing with N2 at 10 L/min, N-benzyltrimethylammonium hydroxide (trade name Triton B) was added until a liquid sample taken in contact with a water-moist pH test strip showed a pH value of 10-11. The bubble column was then brought to the reaction temperature of 120° C. and a gas mixture of propene, oxygen and nitrogen (molar ratio of propene to oxygen 2:1) flowed therethrough, with a total volume flow of less than 10 L/min being regulated. The progress of the reaction or the stationary point was determined by taking liquid and gas samples at the upper sampling points and analyzing them by GC. The product gas mixture produced continuously was freed from propylene oxide by cascaded cooling and the resulting gas stream was again slightly compressed and mixed with propene, oxygen and nitrogen and flowed onto the gassing frit of the bubble column.

The selectivities to propylene oxide were between 95 and 100% in all five experiments.

General experimental procedure for the process for the production of propylene oxide by the oxidation of propene in the presence of the epoxidation catalyst system (2) in a continuous single-bubble column reactor.

3150 mL tetrahydrofuran and 350 mL water were placed under inert conditions in a pressure-resistant bubble column (15 cm diameter) with gassing frit, overpressure protection, pressure sensor, upper and lower liquid outlet, upper addition point for solids and inlet and outlet lines for gases. In each experiment, 0.350 mol of the metal chloride were added to the solvent mixture corresponding oxidation state (see Table 2, 9-12) and 0.700 mol (89.3 g) of elemental iodine were added under protective gas countercurrent. While gassing with N2 at 10 L/min, N-benzyltrimethylammonium hydroxide (trade name Triton B) was added until a liquid sample taken in contact with a water-moist pH test strip showed a pH value of 10-11. The bubble column was then brought to the reaction temperature of 120° C. and a gas mixture of propene, oxygen and nitrogen (molar ratio of propene to oxygen 2:1) flowed therethrough, with a total volume flow of less than 10 L/min being regulated. The progress of the reaction or the stationary point was determined by taking liquid and gas samples at the upper sampling points and analyzing them by GC. The product gas mixture produced continuously was freed from propylene oxide by cascaded cooling and the resulting gas stream was again slightly compressed and mixed with propene, oxygen and nitrogen and flowed onto the gassing frit of the bubble column.

The selectivities to propylene oxide were between 95 and 100% in all four experiments.

General experimental procedure for the process for the production of propylene oxide by the oxidation of propene in the presence of the epoxidation catalyst system (1) in a continuous two-bubble column reactor.

Two pressure-resistant bubble columns (15 cm diameter), each equipped with gassing frit, overpressure protection, pressure sensor, upper and lower liquid withdrawal or addition, upper addition point for solids and inlet and outlet lines for gases are connected via the upper and lower liquid withdrawal via a pump. 3500 mL tetrahydrofuran were placed under inert conditions in one bubble column. In each experiment, 0.350 mol of the metal chloride of the corresponding oxidation state (see Table 1, 1-5) and 0.350 mol of CuCl2 were added to the solvent under protective gas countercurrent. While gassing with nitrogen at 10 L/min, N-benzyltrimethylammonium hydroxide (trade name Triton B) was added until a liquid sample taken in contact with a pH test strip moistened with water showed a pH value of 10-11. The second bubble column was prepared analogously. The bubble columns were then brought to the reaction temperature of 120.degree. A gas mixture of nitrogen and propene flowed against the first bubble column and a gas mixture of nitrogen and oxygen flowed against the second bubble column in both cases a total flow rate of less than 10 L/min was regulated. The molar ratio of propene to oxygen was 2:1. At the same time, the liquid phase was continuously taken out from the first bubble column at the top point and added to the second bubble column at the bottom point, and from the second bubble column at the top point and added to the first bubble column at the bottom point. The volume flows were regulated in such a way that the levels in the two bubble columns did not change over the course of the test. The progress of the reaction or the stationary point was determined by taking liquid and gas samples from the upper sampling points of the two bubble columns and analyzing them by GC. The continuously generated product gas mixture from the first bubble column was freed from propylene oxide by cascaded cooling and the resulting gas stream was slightly compressed again and mixed with nitrogen and propene and flowed onto the gassing frit of the bubble column. The gas stream from the second bubble column was freed from propene by cascaded, cryogenic cooling and disposed of via the exhaust air. The propene recovered was reused by adding it at the lower gassing point of the first bubble column.

General experimental procedure for the process for the production of propylene oxide by the oxidation of propene in the presence of the epoxidation catalyst system (2) in a continuous two-bubble column reactor.

Two pressure-resistant bubble columns (15 cm diameter), each equipped with gassing frit, overpressure protection, pressure sensor, upper and lower liquid withdrawal or addition, upper addition point for solids and inlet and outlet lines for gases are connected via the upper and lower liquid withdrawal via a pump. 3500 mL tetrahydrofuran were placed under inert conditions in one bubble column. In each experiment, 0.350 mol of the metal chloride of the corresponding oxidation state (see Table 2, 9-12) and 0.700 mol (89.3 g) of elemental iodine were added to the solvent under protective gas countercurrent. While gassing with nitrogen at 10 L/min, N-benzyltrimethylammonium hydroxide (trade name Triton B) was added until a liquid sample taken in contact with a pH test strip moistened with water showed a pH value of 10-11. The second bubble column was prepared analogously. the Bubble columns were then brought to the reaction temperature of 120°C. A gas mixture of nitrogen and propene flowed against the first bubble column and a gas mixture of nitrogen and oxygen flowed against the second bubble column, with a total volume flow of less than 10 L/min being regulated in both cases. The molar ratio of propene to oxygen was 2:1. At the same time, the liquid phase was continuously taken out from the first bubble column at the top point and added to the second bubble column at the bottom point, and from the second bubble column at the top point and added to the first bubble column at the bottom point. The volume flows were regulated in such a way that the levels in the two bubble columns did not change over the course of the test. The progress of the reaction or the stationary point was determined by taking liquid and gas samples from the upper sampling points of the two bubble columns and analyzing them by GC. The continuously generated product gas mixture from the first bubble column was freed from propylene oxide by cascaded cooling and the resulting gas stream was slightly compressed again and mixed with nitrogen and propene and flowed onto the gassing frit of the bubble column. The gas stream from the second bubble column was freed from propene by cascaded, cryogenic cooling and disposed of via the exhaust air. The propene recovered was reused by adding it at the lower gassing point of the first bubble column.

General experimental procedure for the process for the production of propylene oxide by oxidation of propene in the presence of the supported epoxidation catalyst system (1) in a continuous gas-phase reactor:

A mixture of 200 mL tetrahydrofuran was placed under inert conditions in a pressure-resistant IL reactor with stirrer, overpressure protection, pressure sensor, riser pipe for liquid removal and gas-injection and degassing lines. For each experiment, 0.350 mol of the metal salt (A) of the corresponding oxidation state (see Table 1, Examples 1-5) and 0.350 mol of CuCl 2 were added to the solvent mixture under protective gas countercurrent. With vigorous stirring, N-benzyltrimethylammonium hydroxide as hydroxide (F) (trade name Triton B) was stirred in until a liquid sample taken came into contact with a water-dampened pH test strip gave a pH of 10-11. The mixture obtained was then applied to silica as a carrier material. The solids were then introduced into an inerted, pressure-resistant and pressure-protected flow reactor. Nitrogen and oxygen were then passed through the flow reactor and the reaction temperature was brought to 180.degree. A quantity of propene was then added to the gas stream until a 2:1 molar ratio of propene to oxygen was achieved and continuously contacted with the solids. The flow conditions and contact time were chosen so that partial conversions were achieved. The continuously generated product gas mixture was in each case freed from propylene oxide by cascaded cooling, and the resulting gas stream was heated again, enriched with oxygen and propene, and the resulting mixture flowed back onto the solid. The gas analysis is carried out by taking gas samples and analyzing them by GC. The selectivities to propylene oxide were between 95 and 100% in all five experiments.

Claims

patent claims

1. epoxidation catalyst system (1) comprising a) a mixture (1) or a reaction product (1) a-1) of a metal salt (A) of the metals chromium (Cr), manganese (Mn), molybdenum (Mo), lead (Pb) and/or bismuth (Bi) and a-2) a hydroxide (B) b) a redox-active compound (C).

2. The epoxidation catalyst system (1) according to claim 1, wherein the metal salt (A) is one or more compounds and is selected from the group consisting of MOCI ₅ , MOOCI ₃ , MnCE, K ₂ MnCl ₆ , CrOCl ₂ , PbCE and BiCE.

3. The epoxidation catalyst system (1) according to claim 1 or 2, wherein the hydroxide (B) is an organic hydroxide (B-I) and the organic hydroxide (B-I) is one or more compound(s) and is selected from the group consisting of 3- (Trifluoromethyl)phenyltrimethylammonium hydroxide, tetra-n-butylphosphonium hydroxide, choline hydroxide, benzyltrimethylammonium hydroxide, tetraethylammonium hydroxide, tetra-n-propylammonium hydroxide, tetrabutylammonium hydroxide and tetramethylammonium hydroxide.

4. epoxidation catalyst system (1) according to any one of claims 1 to 3, wherein the redox-active compound (C) is one or more compound (s) and is selected from the group consisting of CuCl ₂ , Cu (BF4) ₂ , CuCl, VCE, VOCI3, NH4VO3, 1,4-Benzoquinone, 1,4-Naphtoquinone, Se20s, TeCh, TeC>2, Sb2Ü3, Sb20s, CeCE, Co(salen), Co(OAc) ₂ , SnSCE, Fe(acac)3, Mo (acacE, K ₂ Cr2O7, Mn(OAc)3, Ni(CF3CO ₂ H) ₂ and BiCE.

5. epoxidation catalyst system (1) according to any one of claims 1 to 4, wherein the epoxidation catalyst system (1) comprises the reaction product (1) and the reaction product (1) has a structure according to formula (I), (II) and / or (III). :

(Q RiR ₂ R ₃ R ₄ ) ⁺ „ _+om [M(A) ^m+ (Hal)„(OH) _o (S) _p ] ^mno (I) for the case m < n + o

[M(A) ^m+ (Hal) _n (OH) ₀ (S) _p ] (II) for the case m = n + o

[M(A) ^m+ (Hal)„(OH) ₀ (S) _p ] ^(mno) [X] „ _+0-m (III) for the case m > n + o with Q = nitrogen or phosphorus, preferably nitrogen

Ri, R2, R3, R4 independently selected from the group consisting of

(iv) linear or branched alkyl groups containing 1 to 22 C atoms optionally substituted with heteroatoms and/or heteroatom containing substituents;

(v) cycloaliphatic groups containing 3 to 22 C atoms with 1 to 3 bridging C atoms optionally substituted with heteroatoms and/or heteroatom containing substituents and/or

(vi) aryl groups containing 6 to 18 C atoms optionally substituted with 1 to 10 C atoms and/or optionally substituted with heteroatoms and/or heteroatom containing substituents; preferably R1, R2, R3 and R4 are independently selected from the group consisting of methyl, ethyl, isopropyl, n-propyl, isobutyl, t-Bu, n-butyl, phenyl, benzyl, (trifluoromethyl)phenyl

M(A) ^m+ = Mo ⁵⁺ , Mn ⁴⁺ , Cr ⁴⁺ , Pb ⁴⁺ , Bi ⁵⁺ preferably Mo ⁵⁺

Hal=CI, Br or G, preferably CI or Br, particularly preferably CI

S=H2O, THF (tetrahydrofuran), or dioxane, bis(2-methoxyethyl)ether (diglyme), methoxyethanol, polyethylene glycols, pyridine, lutidine, 2,2'-bipyridine, acetonitrile, dimethyl sulfoxide, sulfolane, thiophene, preferably THF; n+o+p = 6n > 1 ; preferably n > 2; particularly preferably n = 2 o > 1; preferably o > 1; particularly preferably o=1; 2; 3 or 4 X = OTf,BF4 , Hai .

6. epoxidation catalyst system (2) comprising c) a mixture (2) or a reaction product (2) c-1) a metal salt (E), c-2) iodine (I2) and c-3) a hydroxide (F) d) optionally a redox active compound (G).

7. The epoxidation catalyst system (2) according to claim 6, wherein the metal salt (E) is one or more compounds and is selected from the group consisting of NiCT. MnCE. PbCl ₂ , SnCl ₂ , CrCl ₃ , VC1 ₃ , MoCU, FeCl ₂ and RUC1 ₃ .

8. epoxidation catalyst system (2) according to claim 6 or 7, wherein the hydroxide (F) is an organic hydroxide (Bl) and the organic hydroxide (Fl) is one or more compound (s) and is selected from the group consisting of 3- (Trifluoromethyl)phenyltrimethylammonium hydroxide, tetra-n-butylphosphonium hydroxide, choline hydroxide, benzyltrimethylammonium hydroxide, tetraethylammonium hydroxide, tetra-n-propylammonium hydroxide, tetrabutylammonium hydroxide and

tetramethylammonium hydroxide.

9. epoxidation catalyst system (2) according to any one of claims 6 to 8, wherein the epoxidation catalyst system (2) comprises the reaction product (2) and the reaction product (2) has a structure according to formula (IV), (V) and / or (VI). :

(Q RiR ₂ R ₃ R ₄ ) ⁺ im- _o -pi [M(E) ^m+ (Hal) _n (OH) _o (S)p] ^mn ° q T ₂ (IV) for the case m < n + O,

[M(E) ^m+ (Hal) _n (OH) ₀ (S) _p ] qT ₂ (V) for the case m = n + o

[M(E) ^m+ (Hal)„(OH) _o (S) _p ] ^mn ° q T ₂ [X] „ _+0-m (VI) for the case m > n + o with

Q = nitrogen or phosphorus, preferably nitrogen

R 1 , R ₂ , R 1 . R ₄ independently selected from the group consisting of

(vi) aryl groups containing 6 to 18 C atoms, optionally substituted with 1 to 10 C atoms and/or optionally substituted with heteroatoms and/or heteroatom-containing substituents; preferably Ri, R ₂ , R and R ₄ independently selected from the group consisting of methyl, ethyl, isopropyl, n-propyl, isobutyl, t-Bu, n-butyl, phenyl, benzyl, (trifluoromethyl) phenyl particularly preferably methyl, benzyl and n-butyl;

M(E) ^m+ = Ni ²⁺ , Mn ²⁺ , Pb ²⁺ , Sn ²⁺ , Cr' . V ³⁺ , Mo ⁴⁺ , Fe ²⁺ or Ru ³⁺ preferably Ni ²⁺ , Mn ²⁺ , Pb ²⁺ ,

Sn ²⁺ ;

Hal = Cl , Br or T, preferably Cl or Br, particularly preferably Cl , n+o+p = 6;

S=H ₂ 0, THF (tetrahydrofuran), or dioxane, bis(2-methoxyethyl)ether (diglyme), methoxyethanol, polyethylene glycols, pyridine, futidine, 2,2'-bipyridine, acetonitrile, dimethyl sulfoxide, sulfolane, thiophene, preferably THF; n >1; preferably n >2; particularly preferably n=2; o >1; preferably o >1; particularly preferably o=1; 2; 3 or 4;

X = OTf,BF4 , Hai ; q>1 preferably 1<q<2000 particularly preferably 1<q<10.

10. A process for preparing epoxides comprising the oxidative reaction of an alkene in a reactor in the presence of the epoxidation catalyst system (1) according to any one of claims 1 to 5 or the epoxidation catalyst system (2) according to any one of claims 6 to 9.

11. The method according to claim 10, wherein the oxidative reaction in the reactor takes place in the presence of oxygen or an oxygen-containing gas mixture.

12. The method according to claim 10 or 11, wherein the alkene is one or more compound (s) and is selected from the group consisting of ethene, propene, butene, 1-octene, butadiene, 1,4-butanediol diallyl ether, allyl chloride, allyl alcohol, Styrene, cyclopentene, cyclohexene, phenyl allyl ether, diallyl ether, n-butyl allyl ether, tert-butyl allyl ether, bisphenol A diallyl ether, resorcinol diallyl ether, triphenylolmethane triallyl ether, cyclohexane-1,2-dicarboxylic acid bis(allyl ester). ), isocyanuric acid tris-(2,3-propene) ester and mixtures of these alkenes, preferably ethene, propene and allyl chloride and particularly preferably propene.

13. The method according to any one of claims 10 to 12, wherein the preparation takes place in the presence of a solvent.

14. The method according to any one of claims 10 to 13, wherein the preparation takes place in the absence of a solvent.

15. The method according to any one of claims 10 to 14, wherein the gas mixture containing the alkene and the oxygen is metered continuously or in stages, preferably continuously, into the reactor.