Zeolite materials with framework structures containing Si, O, and Ti

Abstract

The present invention relates to a zeolitic material having a framework structure comprising Si, O, and Ti, obtained or obtainable from a Ti-containing compound, the Ti-containing compound having an APHA color number of 300 or less. In a second aspect, the present invention relates to a Ti-containing compound having an APHA color number of 300 or less. In a third aspect, the present invention relates to a method for using the Ti-containing compound having an APHA color number of 300 or less of the second aspect to produce a zeolitic material having a framework structure comprising Si, O, and Ti, and a method for producing the zeolitic material of the first aspect having a framework structure comprising Si, O, and Ti, wherein the zeolitic material having a framework structure comprising Si, O, and Ti is produced from the Ti-containing compound having an APHA color number of 300 or less of the second aspect. In a fourth aspect, the present invention relates to a shaped article comprising the zeolitic material having a framework structure comprising Si, O, and Ti of the first aspect, and a method for using the shaped article as an adsorbent, absorbent, catalyst, or catalyst component. A fifth aspect of the present invention is directed to a method for oxidizing an organic compound comprising contacting the organic compound with a catalyst comprising a shaped article according to the fourth aspect, and a sixth aspect relates to propylene oxide obtained or obtainable from the method according to the fifth aspect.

Description

[Technical Field]

[0001] The present invention relates to a zeolitic material having a framework structure comprising Si, O, and Ti, obtained or obtainable from a Ti-containing compound, the Ti-containing compound having an APHA color number of 300 or less. In a second aspect, the present invention relates to a Ti-containing compound having an APHA color number of 300 or less. In a third aspect, the present invention relates to a method for using the Ti-containing compound having an APHA color number of 300 or less of the second aspect to produce a zeolitic material having a framework structure comprising Si, O, and Ti, and a method for producing the zeolitic material of the first aspect having a framework structure comprising Si, O, and Ti, wherein the zeolitic material having a framework structure comprising Si, O, and Ti is produced from the Ti-containing compound having an APHA color number of 300 or less of the second aspect. In a fourth aspect, the present invention relates to a shaped article comprising the zeolitic material having a framework structure comprising Si, O, and Ti of the first aspect, and a method for using the shaped article as an adsorbent, absorbent, catalyst, or catalyst component. A fifth aspect of the present invention is directed to a method for oxidizing an organic compound comprising contacting the organic compound with a catalyst comprising a shaped article according to the fourth aspect, and a sixth aspect relates to propylene oxide obtained or obtainable from the method according to the fifth aspect. [Background technology]

[0002] Propylene oxide is an important intermediate in the chemical industry. A suitable process for its production starts with propylene and uses hydrogen peroxide (H2O2) as the oxidant, a solvent, and an epoxidation catalyst containing a titanium zeolite. Titanium zeolites useful for this purpose include titanium silicate-1 (TS-1), a titanosilicate zeolite with an MFI framework structure. TS-1 has attracted much attention because it enables clean oxidation reactions under relatively mild conditions. TS-1 is typically synthesized hydrothermally using a Ti-containing alcoholate (alkoxide) precursor to control the incorporation of Ti into the zeolite framework. Compounds such as tetraethyl orthotitanate (Ti(OEt)4), tetraisopropyl orthotitanate (Ti(OPr)4), or tetra-n-butyl orthotitanate (Ti(OBu)4) are often used as Ti precursors of choice. It is known that TS-1 obtained by the common preparation method does not contain all Ti as a framework element, but rather a portion of Ti exists as excess framework Ti, e.g., in the form of titanium dioxide (anatase type), due to its strong tendency to polymerize under aqueous conditions.

[0003] US 2013 / 296159 A1 describes a method for producing zeolitic materials, in which, inter alia, tetraethyl orthotitanate (TEOTi, Ti(OEt)4) is used as the titanium source, and EP 0 712 852 A1 is directed to a method for epoxidizing olefins using a TS-1 catalyst.

[0004] D.-G. Huang et al. (Deng-Gao Huang, Xian Zhang, Bao-Hui Chen, Zi-Sheng Chao, Catalysis Today, vol. 158 (2010), pp. 510-514) describe the synthesis of TS-1 by three different procedures using tetraethyl orthosilicate and tetrabutyl orthotitanate as Si and Ti sources and tetrapropylammonium hydroxide as the template. The positive effect of alcohols such as ethanol on the synthesis is described, demonstrating slower hydrolysis of Ti-containing species and reduced production of titanium dioxide (anatase form). Indian published patent application IN189381A discloses that ketones are used to stabilize Ti-containing species and are useful in preventing anatase formation. Thus, the state of the art appears to favor the presence of alcohols and ketones in the synthesis of TS-1. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] US2013 / 296159A1 [Patent Document 2] EP0712852A1 [Patent Document 3] Published Patent Application IN189381A [Non-patent literature]

[0006] [Non-Patent Document 1] D.-G. Huang et al. (Deng-Gao Huang, Xian Zhang, Bao-Hui Chen, Zi-Sheng Chao, Catalysis Today, 158 (2010), pp. 510-514) Summary of the Invention [Problem to be solved by the invention]

[0007] Due to the importance of products such as propylene oxide in industry, it is desirable to carry out the propylene epoxidation reaction as efficiently as possible, including optimizing the catalysts used as much as possible. It is therefore an object of the present invention to provide a zeolitic material having a framework structure comprising Si, O, and Ti that is economically advantageous as a catalyst in processes for the production of propylene oxide.

[0008] Although Ti-containing compounds, such as Ti(OEt)4, are commonly described as colorless liquids, these compounds tend to develop color over time. It has now been surprisingly discovered that the color of the Ti-containing compound is essential to the performance of the final zeolite material produced therefrom, having a framework structure containing Si, O, and Ti. [Means for solving the problem]

[0009] First Aspect—Zeolite Material Having a Framework Structure Comprising Si, O, and Ti Accordingly, in a first aspect, the present invention relates to a zeolitic material having a framework structure comprising Si, O, and Ti obtained or obtainable from a Ti-containing compound, wherein the Ti-containing compound has an APHA color number of 300 or less. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 shows the XRD spectrum of the solid obtained in Comparative Example 2. [Figure 2] FIG. 2 shows the Kubelka-Munk diagrams calculated based on the %R spectra for the titanium silicalite-1 (TS-1) powders of Examples 2 to 4 and Comparative Examples 1 and 2. [Figure 3] FIG. 3 shows the Kubelka-Munk diagram calculated based on the %R spectra for the TiMWW powders of Example 6 and Comparative Example 3. [Figure 4] FIG. 4 shows the results of the continuous epoxidation reaction of Example 7.2, with the cooling medium temperature on the y-axis and the runtime on the x-axis. [Figure 5]FIG. 5 shows the results of the continuous epoxidation reaction of Example 7.2, with the selectivity of propylene oxide over hydrogen peroxide (S(H2O2) vs. PO) on the y-axis and run time on the x-axis. [Figure 6] FIG. 6 shows a summary of the results of the sequential epoxidation reactions of Example 7.2. DETAILED DESCRIPTION OF THE INVENTION

[0011] The APHA color number in the context of the present invention is determined in accordance with DIN EN ISO 6271:2016-05. An APHA color number of a Ti-containing compound of 300 or less preferably means an APHA color number in the range of 0 (zero) to 300. More preferably, the APHA color number is 290 or less (range 0 to 290), more preferably 280 or less (range 0 to 280), more preferably 270 or less (range 0 to 270), more preferably 260 or less (range 0 to 260), more preferably 251 or less (range 0 to 251), more preferably 250 or less (range 0 to 250), more preferably 200 or less (range 0 to 200), more preferably 150 or less (range 0 to 150), and more preferably 105 or less (range 0 to 105).

[0012] Surprisingly, it has been found that when zeolitic materials having a framework structure containing Si, O, and Ti, obtained or obtainable from a Ti-containing compound, where the Ti-containing compound has an APHA color number of 300 or less, are used as catalysts in the preferably continuous epoxidation of C2-C5 alkylenes with hydrogen peroxide, the catalytic performance, particularly selectivity, decreases as the APHA number of the Ti-containing compound used in the synthesis of the zeolitic material increases. When the APHA number exceeds 300, much higher temperatures (and therefore higher cooling medium temperatures) are required in the epoxidation zone in order to maintain hydrogen peroxide conversion comparable to that achieved when Ti-containing compounds are used in the synthesis of zeolitic materials with APHA numbers of 300 or less. However, when these zeolitic materials based on Ti-containing compounds having such high APHA numbers are used as catalysts, the selectivity is low, e.g., less than 85%, even at higher temperatures. For example, in the epoxidation of propylene with hydrogen peroxide, the selectivity of propylene oxide to hydrogen peroxide (S(H2O2) vs. PO) can be significantly improved. Even though the results of different catalysts appear comparable during initial run times, at longer run times, e.g., greater than 150 hours, preferably greater than 200 hours, and more preferably greater than 250 hours, catalysts based on Ti-containing compounds having APHA color numbers of 300 or less provide significantly higher selectivities of 85% or greater (ranging from 85 to 95%). Catalysts based on Ti-containing compounds having APHA color numbers greater than 300 provide selectivities of less than 85% at longer run times.

[0013] The zeolitic material having a framework structure comprising Si, O, and Ti is obtained or obtainable from a Ti-containing compound as described above. Preferably, the Ti-containing compound comprises a Ti-containing alcoholate (alkoxide), preferably selected from the group of Ti(O-alkyl)4, where each alkyl group is a branched or unbranched C1-C6 alkyl, more preferably selected from the group consisting of tetraethyl orthotitanate (Ti(OEt)4), tetraisopropyl orthotitanate (Ti(OPr)4), tetra-n-butyl orthotitanate (Ti(OBu)4), and mixtures of two or more of these compounds, more preferably tetraethyl orthotitanate (Ti(OEt)4), tetraisopropyl orthotitanate (Ti(OPr)4), and mixtures of Ti(OEt)4 and Ti(OPr)4.

[0014] Preferably, the Ti-containing compound from which the zeolitic material having a framework structure containing Si, O, and Ti has been obtained or can be obtained comprises at least 90% by mass, preferably at least 95% by mass, more preferably at least 96% by mass, more preferably at least 97% by mass, more preferably at least 98% by mass, more preferably at least 99% by mass of Ti-containing alcoholate, based on the total mass of the Ti-containing compounds. "At least 90% by mass" means a value in the range of 90 to 100% by mass, and the same applies to the other values ​​mentioned above.

[0015] Preferably, the Ti-containing compound from which the zeolitic material having a framework structure containing Si, O, and Ti is obtained or can be obtained is present in an amount of 10% by mass or less, more preferably 5% by mass or less, more preferably 4% by mass or less, more preferably 3% by mass or less, more preferably 2% by mass or less, more preferably 1% by mass or less of the general formula (I), based on the total mass of the Ti-containing compound. [ka] (In the formula, R, R 1 and R 2 are independently selected from the group consisting of a hydrogen atom and a branched or unbranched C1-C6 alkyl, and R 3is selected from the group consisting of a hydrogen atom, a branched or unbranched C1-C6 alkyl, and a branched or unbranched C1-C6 alkenyl. "10% by mass or less" means a value in the range of 0 (zero) to 10% by mass, and the same applies to the other values ​​above.

[0016] The substance of formula (I) may be present in the form of a monomer as shown in formula (I) or in the form of an oligomer having 2 to 7 repeating units. These oligomers are present in an amount of less than 100 ppm, preferably less than 50 ppm, and more preferably less than 10 ppm, based on the total mass of the Ti-containing compound. The Ti-containing compound may contain, in addition to one or more substances of formula (I), a compound of formula (II): [ka] (In the formula, R 4 , R 5 and R 6 are independently selected from a hydrogen atom and a branched or unbranched C1-C6 alkyl). The material of formula (I) is preferably selected from the group consisting of CH3-CH=CH-C(=O)-CH=CH-CH3 (hepta-2,5-dien-4-one), (CH3)2C=CH-C(=O)-CH=C(CH3)2 (phorone, 2,6-dimethyl-hepta-2,5-dien-4-one), and a mixture of hepta-2,5-dien-4-one and 2,6-dimethyl-hepta-2,5-dien-4-one. In embodiments where the Ti-containing compound comprises Ti(OEt)4, the material of formula (I) comprises at least CH3-CH=CH-C(=O)-CH=CH-CH3 (hepta-2,5-dien-4-one). In embodiments in which the Ti-containing compound comprises Ti(OPr), the material of formula (I) comprises at least (CH)C=CH-C(=O)-CH=C(CH)(2,6-dimethyl-hepta-2,5-dien-4-one).

[0017] As described above, it has surprisingly been found that when zeolitic materials are used as catalysts in the preferably continuous epoxidation of C2-C5 alkylenes with hydrogen peroxide, catalytic performance, particularly selectivity, decreases as the APHA number of the Ti-containing compound used in the synthesis of the zeolitic material increases. Therefore, it can be concluded that coloration of Ti-containing compounds, including Ti-containing alcoholates (APHA color number of 300 or less, as determined according to DIN EN ISO 6271:2016-05), should be avoided in the synthesis of zeolitic materials. Without being bound by this theory, it is hypothesized that residual amounts of water in Ti-containing compounds, including Ti-containing alcoholates, destroy the alcoholates and produce TiO. The TiO, which can be determined in the final zeolitic material, appears to act as a photosensitizer and catalyze the oxidation of the remaining alcoholates, such as isopropanolate or ethanolate, to the respective carbonyl (C=O)-containing compounds (aldehydes or ketones). Carbonyl-containing compounds, such as acetaldehyde or acetone, undergo aldol condensation under strongly basic conditions, and the resulting aldol condensation products correspond to formula (I). These aldol condensation products contribute color and interfere with the synthesis of zeolitic materials with framework structures containing Si, O, and Ti.

[0018] The zeolitic material having a framework structure containing Si, O, and Ti, obtained or obtainable from the above Ti-containing compound, preferably has a titanium dioxide content of 1.5% by weight or less, preferably 1.2% by weight or less, more preferably 1% by weight or less, more preferably 0.5% by weight or less, based on the total weight of the zeolitic material, and preferably at least 98% by weight of the titanium dioxide is in the anatase form as determined according to Reference Example 7.

[0019] The zeolitic material having a framework structure containing Si, O, and Ti, obtained or obtainable from the Ti-containing compound, preferably has a crystallinity, determined according to Reference Example 7, of greater than 85% by mass, preferably in the range of 85 to 95% by mass, more preferably in the range of 87 to 93% by mass, based on the total mass of the zeolitic material. The zeolitic material having a framework structure containing Si, O, and Ti, obtained or obtainable from the Ti-containing compound, preferably exhibits a propylene oxide activity, determined as described in Reference Example 1, of at least 8.5% by mass, more preferably in the range of 8.5 to 9.5% by mass, more preferably in the range of 8.5 to 9.0% by mass. Preferably, the zeolitic material has a crystallinity, determined as described in Reference Example 4, of 440 to 580 m 2 / g, preferably 450 to 570 m 2 The BET specific surface area in the range of / g is shown.

[0020] Preferably, 95 to 100% by mass, preferably 98 to 100% by mass, more preferably 99 to 100% by mass, more preferably 99.5 to 100% by mass, more preferably 99.9 to 100% by mass of the zeolitic material obtained or obtainable from the Ti-containing compound described above, consists of Si, O, Ti, and optionally H. Preferably, the zeolitic material contains Ti in an amount in the range of 0.2 to 5% by mass, more preferably in the range of 0.5 to 4% by mass, more preferably in the range of 1.0 to 3% by mass, more preferably in the range of 1.2 to 2.5% by mass, more preferably in the range of 1.4 to 2.2% by mass, calculated as elemental Ti and based on the total mass of the zeolitic material.

[0021] Preferably, the zeolite material having a framework structure containing Si, O, and Ti obtained or obtainable from the above Ti-containing compound is selected from the group consisting of ABW, ACO, AEI, AEL, AEN, AET, AFG, AFI, AFN, AFO, AFR, AFS, AFT, AFX, AFY, AHT, ANA, APC, APD, AST, ASV, ATN, ATO, ATS, ATT, ATV, AWO, AWW, BCT, BEA, BEC, BIK, BOG, BPH, BRE, CAN, CAS, CDO, CFI, CGF, CGS, CHA, CHI, CLO, CON, CZP, DAC, DDR, DFO, DFT, DOH, DON, EAB, EDI, EMT, EPI, ERI, ESV, ETR, EUO, FAU, FER, FRA, GIS, GIU, GME, GON, GOO, HEU, IFR, ISV, ITE, ITH, ITQ,ITW, IWR, IWW, JBW, KFI, LAU, LEV, LIO, LOS, LOV, LTA, LTL, LTN, MAR, MAZ, MCM-22(S), MCM-36, MCM-56, MEI, MEL, MEP, MER, MIT-1, MMFI, MFS, MON, MOR, MSE, MSO, MTF, MTN, MTT, MTW, MWW, NAB, NAT, NEES, NON, NPO, OBW, OFF, OSI, OSO, PAR, PAU, PHI, PON, RHO, RON, RRO, RSN, RTE, RTH, RUT, RWR, RWY, SAO, SAS, SAT, SAV, SBE, SBS, SBT, SFE, SFF, SFG, SFH, SFN SFO, SGT, SOD, SSY, STF, STI, STT, TER, THO, TON, TSC, UEI, UFI, UOZ, USI, UTL, VET, VFI, VNI, VSV, WEI, WEN, YUG, ZON The zeolite material may be a titanium zeolite having an SVR or SVY framework structure or a mixed structure of two or more of these framework structures. More preferably, the zeolite material having a framework structure containing Si, O, and Ti is an MFI framework type, a MEL framework type, an MWW framework type, an MCM-22(S) framework type, an MCM-56 framework type, an IEZ-MWW framework type, an MCM-36 framework type, an ITQ framework type, a BEA framework type, an MOR framework type, or a mixed structure of two or more of these framework types. More preferably, the zeolite material has an MFI framework type or an MWW framework type. More preferably, the zeolite material having a framework structure containing Si, O, and Ti has a framework type MFI. More preferably, the zeolite material having a framework structure containing Si, O, and Ti is titanium silicalite-1 (TS-1). Framework types such as MCM-22(S), MCM-56, IEZ-MWW, ITQ (exfoliated MWW), MIT-1, and MCM-36 are titanium zeolites with framework structures related to the MWW framework structure and are or can be obtained therefrom or from their respective two-dimensional precursors, for example by layer expansion and / or post-modification.

[0022] There is no limitation on the method for preparing a zeolite material having a framework structure containing Si, O, and Ti from a Ti-containing compound, provided that the zeolite material is ultimately achieved. Suitable methods for such synthesis include the commonly known hydrothermal synthesis method and are known to those skilled in the art.

[0023] In one embodiment, a zeolitic material having a framework structure comprising Si, O, and Ti is prepared from one or more Si sources, one or more Ti-containing compound(s), and one or more structure-directing agent(s) by appropriately mixing these compounds in the presence of water to obtain an aqueous mixture, which is then crystallized at elevated temperature and pressure.

[0024] Si source The one or more sources of Si are one or more compounds selected from the group consisting of silica, silicates, and mixtures thereof, preferably from the group consisting of fumed silica, silica hydrosol, reactive amorphous solid silica, silica gel, silicic acid, water glass, sodium metasilicate hydrate, sesquisilicate, disilicate, colloidal silica, pyrogenic silica, silicate esters, tetraalkoxysilanes, and mixtures of two or more thereof, more preferably from the group consisting of silica hydrosol, silica gel, silicic acid, water glass, sodium metasilicate hydrate, colloidal silica, silicate esters, tetraalkoxysilanes, and mixtures of two or more thereof, more preferably from the group consisting of silica hydrosol, silicic acid, colloidal silica, silicate esters, tetraalkoxysilanes, and mixtures of two or more thereof. Preferably, the one or more sources of Si comprise a mixture of one or more tetraalkoxysilanes selected from the group consisting of (C1-C6) tetraalkoxysilanes and mixtures of two or more thereof, preferably (C1-C5) tetraalkoxysilanes and mixtures of two or more thereof, more preferably (C1-C4) tetraalkoxysilanes and mixtures of two or more thereof, more preferably (C1-C3) tetraalkoxysilanes and mixtures of two or more thereof, more preferably the one or more sources of Si comprise tetramethoxysilane and / or tetraethoxysilane, preferably tetraethoxysilane, and more preferably the one or more sources of Si are tetramethoxysilane and / or tetraethoxysilane, preferably tetraethoxysilane (tetraethyl orthosilicate).

[0025] Structure Directing Agents Preferably, the one or more structure directing agent(s) comprise one or more compound(s) selected from the group consisting of amines, quaternary ammonium compounds, alcohols, and mixtures of two or more of these agents. Preferably, the one or more structure directing agent(s) comprise a tetraalkylammonium cation R 1 R 2 R 3 R 4 N + wherein R is selected from the group consisting of1 , R 2 , R 3 and R 4 each independently represents a C1 to C10 alkyl group. 1 , R 2 , R 3 , and R 4 represents an optionally branched C1-C6 alkyl group, preferably a C1-C5 alkyl group, more preferably a C2-C4 alkyl group, and more preferably an optionally branched C2-C3 alkyl group, and more preferably, each of R 1 , R 2 , R 3 , and R 4 represents ethyl or propyl, more preferably R 1 , R 2 , R 3 , and R 4 All of these represent propyl, preferably n-propyl.

[0026] one or more tetraalkylammonium cations R 1 R 2 R 3 R 4 N + The containing compounds are, independently of one another, salts, more preferably halides, preferably chlorides and / or bromides, more preferably one or more salts selected from the group consisting of chlorides, hydroxides, sulfates, nitrates, phosphates, acetates, and mixtures of two or more thereof, more preferably one or more salts selected from the group consisting of chlorides, hydroxides, sulfates, and mixtures of two or more thereof, more preferably one or more tetraalkylammonium cations R 1 R 2 R 3 R 4 N + The containing compound is a tetraalkylammonium hydroxide and / or chloride, and more preferably a tetraalkylammonium hydroxide.The one or more structure directing agent(s) are preferably used in the form of an aqueous solution.

[0027] For details of the one or more Ti-containing compound(s), see the second aspect described below. As described in more detail below, the one or more Ti-containing compound(s) are Ti-containing compound(s) having an APHA color number of 300 or less.

[0028] In one embodiment, a zeolitic material having a framework structure comprising Si, O, and Ti can be prepared by the following steps: a) preparing a mixture comprising one or more Si sources, one or more Ti-containing compound(s) and one or more structure directing agent(s), and water; b) feeding the mixture prepared in step (a) into a reactor; and c) crystallizing a zeolitic material having a framework structure comprising Si, O, and Ti from the mixture in a reactor, the mixture being heated to a temperature in the range of 70 to 300°C; It is prepared by a method comprising:

[0029] There are no limitations on the method and order of mixing one or more Si sources, one or more Ti-containing compounds, one or more structure-directing agents, and water. In some embodiments, one or more Ti-containing compounds and one or more structure-directing agents are premixed, preferably in an aqueous solution, in a sealed container before step a), followed by removing the formed alcohol by distillation to obtain an aqueous solution containing the reaction product of one or more Ti-containing compounds and one or more structure-directing agents. For example, when tetraethyl orthotitanate (Ti(OEt)4) is used as the Ti-containing compound and aqueous tetrapropylammonium hydroxide solution is used as the structure-directing agent, the reaction product is an aqueous Ti-tetrapropylammonium hydroxide solution.

[0030] When premixing is performed, the zeolite material having a framework structure containing Si, O, and Ti can be prepared by the following steps: a') preparing a mixture comprising one or more Si sources, a reaction product from premixing one or more Ti-containing compound(s) with one or more structure directing agent(s), and water; b) feeding the mixture prepared in step (a') into a reactor; and c) crystallizing a zeolitic material having a framework structure comprising Si, O, and Ti from the mixture in a reactor, the mixture being heated to a temperature in the range of 70 to 300°C; It is prepared by a method comprising:

[0031] Preferably, the reactors of steps b) and c) are pressure-resistant, for example autoclaves.

[0032] The process can be carried out batchwise (batch mode) or continuously (continuous mode). Preferably, for the continuous mode, at least one of steps a), b) and c), and at least one of steps a'), b and c), respectively, are carried out continuously. More preferably, for the continuous mode, all of steps a), b) and c), and a'), b) and c), respectively, are carried out continuously. For the continuous process, it is preferred to use continuous flow reactors as reactors for b) and c).

[0033] The molar ratio of water to one or more Si sources, calculated as SiO, HO:Si is preferably in the range of 100:1 to 10:1 in the mixtures prepared in (a) and (a'), respectively. The molar ratio of one or more Si sources, calculated as SiO, to one or more Ti-containing compound(s), calculated as TiO, Si:Ti, is preferably in the range of 1:100 to 100:1, more preferably in the range of 1:50 to 50:1, more preferably in the range of 10:1 to 50:1 in the mixtures prepared in (a) and (a'), respectively. The molar ratio of one or more structure directing agent(s):one or more Ti-containing compounds, calculated as TiO, is preferably in the range of 5:1 to 100:1, more preferably in the range of 10:1 to 50:1, more preferably in the range of 20:1 to 40:1 in the mixtures prepared in (a) and (a'), respectively.

[0034] Step c) is preferably carried out at a temperature in the range of 90 to 280°C, more preferably 110 to 250°C, more preferably 130 to 220°C, more preferably 150 to 200°C, more preferably 160 to 190°C, and more preferably 170 to 180°C. c) is more preferably carried out under autogenous pressure, and preferably the pressure is in the range of 0.5 to 15 MPa, more preferably 1 to 12 MPa, more preferably 1.5 to 11 MPa, and more preferably 2 to 10 MPa. Here, and below, the unit bar means bar (abs), and 10 5 Pa (1 bar = 10 5 It refers to absolute pressure (Pa).

[0035] Prior to b), the mixture prepared in a) is preferably aged at a temperature in the range of 15 to 120°C, more preferably 20 to 115°C, more preferably 22 to 100°C. The aging is preferably carried out for a time in the range of 0.05 to 48 hours, more preferably 0.15 to 24 hours, more preferably 0.25 to 12 hours, more preferably 0.5 to 6 hours, more preferably 0.75 to 3 hours, more preferably 1 to 2 hours. The alcohol formed during the aging is preferably at least partially removed by distillation.

[0036] The method may include further process steps, such as: d) treating the reaction product effluent leaving the reactor in step c) with a liquid comprising one or more solvents and / or by expansion of the reaction product effluent; and / or, preferably, and e) separating the zeolitic material obtained in step c) or d); f) optionally washing the zeolitic material obtained in step c), d) or f), g) drying the zeolitic material obtained in step c), d), e), or f); and / or, preferably, and h) calcining the zeolitic material obtained in step c), d), e), f) or g); It is preferred that the composition further comprises:

[0037] When the method includes g), the drying in g) is preferably carried out at a temperature in the range of 50 to 220°C, preferably 70 to 190°C, more preferably 80 to 170°C, more preferably 90 to 150°C, more preferably 100 to 140°C, and more preferably 110 to 130°C, for a time in the range of preferably 1 to 10 hours, more preferably 2 to 8 hours, and more preferably 3 to 6 hours.

[0038] When the method includes h), the calcination in step h) is preferably carried out at a temperature in the range of 300 to 700°C, more preferably 375 to 625°C, more preferably 425 to 575°C, more preferably 470 to 550°C. There is no limitation regarding the duration of the calcination, as long as the final calcined product obtained from h) has a suitable three-dimensional zeolite structure, which can be easily determined by a person skilled in the art, for example, by measuring and analyzing X-ray diffraction (XRD) data. For example, in the case of a batch process, the calcination is preferably carried out for a time in the range of 1 to 10 hours, more preferably 2 to 8 hours, more preferably 3 to 6 hours.

[0039] Second embodiment—Ti-containing compound having an APHA color number of 300 or less In a second aspect, the present invention relates to a Ti-containing compound having an APHA color number of not more than 300. Preferably, the Ti-containing compound comprises a Ti-containing alcoholate, preferably selected from the group of Ti(O-alkyl)s, wherein each alkyl group is independently selected from branched or unbranched C1-C6 alkyls, more preferably from the group consisting of tetraethyl orthotitanate (Ti(OEt)), tetraisopropyl orthotitanate (Ti(OPr)), tetra-n-butyl orthotitanate (Ti(OBu)) and mixtures of two or more of these compounds, more preferably from the group of tetraethyl orthotitanate (Ti(OEt)), tetraisopropyl orthotitanate (Ti(OPr)) and mixtures of Ti(OEt) and Ti(OPr).

[0040] Preferably, the Ti-containing compound having an APHA color number of 300 or less contains at least 90% by mass, preferably at least 95% by mass, more preferably at least 96% by mass, more preferably at least 97% by mass, more preferably at least 98% by mass, and more preferably at least 99% by mass of a Ti-containing alcoholate, based on the total mass of the Ti-containing compound. The Ti-containing compound preferably contains at most 10% by mass, more preferably at most 5% by mass, more preferably at most 4% by mass, more preferably at most 3% by mass, more preferably at most 2% by mass, and more preferably at most 1% by mass of a compound represented by formula (I) [ka] (In the formula, R, R 1 and R 2 are independently selected from the group consisting of a hydrogen atom and a branched or unbranched C1-C6 alkyl, and R 3 is selected from the group consisting of a hydrogen atom, branched or unbranched C1-C6 alkyl, and branched or unbranched C1-C6 alkenyl. The substance of formula (I) is preferably selected from the group consisting of CH3-CH=CH-C(=O)-CH=CH-CH3 (hepta-2,5-dien-4-one), (CH3)2C=CH-C(=O)-CH=C(CH3)2 (phorone = 2,6-dimethyl-hepta-2,5-dien-4-one), and a mixture of hepta-2,5-dien-4-one and 2,6-dimethyl-hepta-2,5-dien-4-one.

[0041] Third Aspect—Method of Use of Ti-Containing Compounds In a third aspect, the present invention relates to a method for using the Ti-containing compound having an APHA color number of 300 or less as described above in relation to the second aspect to produce a zeolitic material having a framework structure comprising Si, O, and Ti according to the first aspect above. Thus, the present invention also relates to a method for producing a zeolitic material having a framework structure comprising Si, O, and Ti, wherein the zeolitic material having a framework structure comprising Si, O, and Ti is produced from a Ti-containing compound having an APHA color number of 300 or less, the Ti-containing compound being as described above in relation to the second aspect.

[0042] Fourth aspect - Molded articles In a fourth aspect, the present invention further relates to a molded article comprising a zeolite material having a framework structure comprising Si, O, and Ti according to the first aspect above.

[0043] Preferably, the molded article exhibits a tortuosity parameter for water of less than 4, more preferably in the range of 1.0 to 2.5, more preferably in the range of 1.3 to 2.0, more preferably in the range of 1.40 to 1.80, more preferably in the range of 1.50 to 1.75, more preferably in the range of 1.55 to 1.70, determined as described in Reference Example 5. The pore volume of the molded article, determined according to DIN 66133:1993-06, is preferably in the range of 0.1 to 1.5 ml / g.

[0044] Furthermore, according to a fourth aspect, the present invention relates to the use of the shaped article as an adsorbent, absorbent, catalyst or catalyst component, preferably as a catalyst or catalyst component, more preferably as a Lewis acid catalyst or Lewis acid catalyst component, as an isomerization catalyst or isomerization catalyst component, as an oxidation catalyst or oxidation catalyst component, as an aldol condensation catalyst or aldol condensation catalyst component, or as a Prins reaction catalyst or Prins reaction catalyst component.

[0045] With regard to the above-mentioned use as an oxidation catalyst or an oxidation catalyst component, the molded article is preferably used as an epoxidation catalyst or an epoxidation catalyst component, more preferably as an epoxidation catalyst. Preferably, the molded article is used in the epoxidation reaction of an organic compound having at least one C-C double bond, preferably a C2-C10 alkene, more preferably a C2-C5 alkene, more preferably a C2-C4 alkene, more preferably a C2 or C3 alkene, more preferably propene, more preferably for the epoxidation of propene using hydrogen peroxide as an oxidant, more preferably for the epoxidation of propene using hydrogen peroxide as an oxidant in a solvent containing an alcohol, preferably methanol.

[0046] Fifth Aspect - Method for Oxidizing Organic Compounds In a fifth aspect, the present invention relates to a process for oxidizing an organic compound, preferably for epoxidizing an organic compound, more preferably for epoxidizing an organic compound having at least one C-C double bond, preferably a C2-C10 alkene, more preferably a C2-C5 alkene, more preferably a C2-C4 alkene, more preferably a C2 or C3 alkene, more preferably propene, comprising contacting the organic compound, preferably in a continuous mode, with a catalyst comprising a molded article according to the fourth aspect. Hydrogen peroxide is preferably used as the oxidizing agent, and the oxidation (epoxidation) reaction is preferably carried out in a solvent, more preferably a solvent comprising an alcohol, preferably methanol. More preferably, the oxidation (epoxidation) reaction is carried out in a solvent mixture comprising a solvent and water, more preferably a solvent mixture comprising an alcohol, preferably methanol, and water.

[0047] Also, according to a fifth aspect, the present invention relates to a process for producing propylene oxide, which comprises reacting propene, preferably in a continuous mode, with hydrogen peroxide in a solvent in the presence of a catalyst comprising the molded article according to the fourth aspect to obtain propylene oxide. The reaction of propene with hydrogen peroxide in a solvent in the presence of a catalyst is preferably carried out in the epoxidation zone at an absolute pressure in the range of 0.5 to 5.0 MPa, preferably in the range of 1.5 to 3.0 MPa, more preferably in the range of 1.8 to 2.8 MPa.

[0048] Preferably, the reaction of propene with hydrogen peroxide in a solvent in the presence of a catalyst is carried out in the epoxidation zone at a temperature in the range of 33 to 73 °C, preferably 38 to 63 °C, more preferably 53 to 63 °C. The temperature in the epoxidation zone is measured using ten thermocouples, i.e., ten thermoelements. The epoxidation zone is defined as the region in which the reaction of hydrogen peroxide with propylene to form propylene oxide still occurs in detectable amounts (10 ppm or more propylene oxide). Preferably, the epoxidation zone extends over the entire length of the catalyst bed, i.e., the region in the reactor where the epoxidation catalyst is present (epoxidation zone = catalyst bed). The hot spot, i.e., the region where maximum reaction occurs, is typically located in the first half of the catalyst bed, preferably with at least six of the ten thermoelements located in the first half of the catalyst bed.

[0049] The temperature in the epoxidation zone is the average temperature determined from the temperature values ​​measured by all the thermoelectric elements located in the first half of the catalyst bed. Typically, the temperature values ​​measured by these thermoelectric elements differ from each other and range from 6 to 10 °C.

[0050] Preferably, a cooling medium is used to adjust the temperature of the epoxidation zone, and the temperature of the cooling medium is preferably in the range of 25 to 65°C, preferably in the range of 30 to 55°C, and more preferably in the range of 345 to 55°C. The cooling medium temperature is preferably the temperature of the cooling medium at the inlet to the reactor. A cooling medium temperature of 45 to 55°C is the optimal temperature range. Temperatures below 45°C are associated with the initial stage of the epoxidation reaction and are too low for efficient tempering during the epoxidation reaction. Above 55°C, the decomposition of hydrogen peroxide and the formation of oxygen increase exponentially. With the cooling medium in the range of 45 to 55°C, the temperature of the epoxidation zone is in the optimal range of 53 to 63°C, thereby achieving maximum selectivity and optimal activity.

[0051] In the method for producing propylene oxide, the mass ratio (w / w) of propylene to hydrogen peroxide is preferably in the range of 1:1 to 6:1, more preferably in the range of 1:1 to 2:1 or in the range of 4:1 to 5:1. The mass ratio (w / w) of solvent to hydrogen peroxide is preferably in the range of 15:1 to 5:1, more preferably in the range of 12:1 to 6:1, or more preferably in the range of 11:1 to 8:1. The mass ratio (w / w) of solvent to propylene in the reaction mixture is in the range of 10:1 to 1:0.1, preferably in the range of 9:1 to 1:1, more preferably in the range of 9:1 to 7:1 or in the range of 1.5:1 to 1:1.

[0052] The solvent is preferably an organic solvent, more preferably an organic epoxidation solvent. More preferably, the organic solvent is selected from the group consisting of alcohol, acetonitrile, tert-butanol, propionitrile, and a mixture of two or more thereof. More preferably, the organic solvent is selected from the group consisting of alcohol, acetonitrile, and a mixture of alcohol and acetonitrile. More preferably, the organic solvent contains at least an alcohol. "The organic solvent contains at least an alcohol" means that at least 90% by mass, preferably at least 95% by mass, more preferably at least 98% by mass, and more preferably at least 99% by mass of the organic solvent is alcohol, based on the total mass of the organic solvent. The alcohol is preferably a C1-C5 monoalcohol or a mixture of two or more C1-C5 alcohols. More preferably, the alcohol contains at least methanol, and more preferably, the alcohol is methanol. According to a preferred embodiment, the organic solvent is methanol.

[0053] There are no limitations regarding the water used in the solvent mixture. For example, water treated with NH3 can be used, but water not treated with NH3 can also be used. It is preferable to use deionized water in the reaction mixture. Deionized water can be obtained using an ion exchanger using condensate. Typical grades of deionized water are defined in ISO 3696 of 1987, and any grade described therein can be used within the scope of the present invention. The water may further contain trace amounts of corrosion inhibitors such as ammonia, hydrazine, or hydroxylamine; in that case, the pH value should be in the range of 7 to 9 (measured using a calibrated glass electrode). Preferably, the water used does not contain corrosion inhibitors.

[0054] Generally, the so-called "reaction mixture" comprises propylene, water, an organic solvent, and hydrogen peroxide and can be provided in any conceivable manner. Preferably, the reaction mixture comprising propylene, water, an organic solvent, and hydrogen peroxide or a hydrogen peroxide source is prepared from two or more streams. More preferably, the reaction mixture is provided by combining at least three individual streams, wherein a first stream comprises hydrogen peroxide or a hydrogen peroxide source, optionally as an aqueous solution, a second stream comprises propylene and optionally propane, and a third stream comprises an organic solvent and optionally water.

[0055] Generally, pure or essentially pure propylene is contemplated as the starting material and as part of the reaction mixture. Preferably, a mixture of propylene and propane is used. Most preferably, industrial-grade propylene according to international standards such as ASTM D5273 or DIN 51622 is used. When a mixture of propylene and propane is used, the propylene:propane mass ratio is preferably at least 7:3. For example, commercially available propylene that can be used can be either polymer-grade propylene or chemical-grade propylene. Typically, polymer-grade propylene has a propylene content in the range of 99 to 99.8% by mass and a propane content in the range of 0.2 to 1% by mass. Chemical-grade propylene typically has a propylene content in the range of 92 to 98% by mass and a propane content in the range of 2 to 8% by mass. According to a preferred embodiment of the present invention, a mixture of propylene and propane is used having a propylene content in the range of 99 to 99.8% by mass and a propane content in the range of 0.2 to 1% by mass.

[0056] Preferably, hydrogen peroxide is used in the form of an aqueous hydrogen peroxide solution, which has a total organic carbon content (TOC) measured in accordance with DIN EN 1484 of 100 to 800 mg per kg of hydrogen peroxide, more preferably 120 to 750 mg per kg of hydrogen peroxide, and even more preferably 150 to 700 mg per kg of hydrogen peroxide.

[0057] Generally, there are no particular limitations on the pH value of the aqueous hydrogen peroxide solution or the amount of hydrogen peroxide contained in the solution, so long as the epoxidation of propylene can be carried out efficiently. Preferably, the aqueous hydrogen peroxide solution has a pH in the range of 0 to 3.0, more preferably 0.1 to 2.5, and more preferably 0.5 to 2.3, as determined as described in Reference Example 4. Preferably, the aqueous hydrogen peroxide solution contains 20 to 80% by mass, preferably 30 to 70% by mass, and more preferably 40 to 60% by mass of hydrogen peroxide, based on the total mass of the aqueous hydrogen peroxide solution. Generally, there are no particular limitations on the source of the aqueous hydrogen peroxide solution, so long as the epoxidation of propylene can be carried out efficiently. Preferably, the aqueous hydrogen peroxide solution is obtained or can be obtained by the anthraquinone process.

[0058] According to one embodiment of the present invention, it is preferable to use an aqueous hydrogen peroxide solution obtained as a crude hydrogen peroxide solution by extraction of a mixture obtained from a process known as the anthraquinone process (see, for example, Ullmann's Encyclopedia of Industrial Chemistry, 5th Edition, Vol. A13 (1989), pp. 443-466). The anthraquinone solution preferably contains an alkyl group having 2 to 10 carbon atoms, more preferably 2 to 6 carbon atoms, and more preferably 2, 5, or 6 carbon atoms. The solvent used usually consists of a mixture of at least two different solvents. Preferably, a mixture of two solvents or a mixture of three solvents is used. Preferably, none of the solvents used in the anthraquinone process contain nitrogen-containing substances. This anthraquinone solution is usually referred to as a working solution. In this process, hydrogen peroxide formed during the anthraquinone process is generally separated by extraction from the respective working solutions after the hydrogenation / reoxidation cycle. The extraction can be preferably carried out with essentially pure water, and a crude aqueous hydrogen peroxide solution is obtained. The crude aqueous hydrogen peroxide solution thus obtained can generally be further purified and / or concentrated by distillation. It is also possible to use a crude aqueous hydrogen peroxide solution that has not been purified and / or concentrated by distillation, or to use an aqueous hydrogen peroxide solution that has been purified and / or concentrated by distillation. Furthermore, it is generally possible to subject the crude aqueous hydrogen peroxide solution to a further extraction step in which a suitable extractant, preferably an organic solvent, is used. More preferably, the organic solvent used in this further extraction step is the same solvent as used in the anthraquinone process. Preferably, extraction is carried out using only one of the solvents in the working solution, most preferably the most non-polar solvent in the working solution. When the crude aqueous hydrogen peroxide solution is subjected to such a further extraction step, a so-called crude wash hydrogen peroxide solution is obtained. According to a preferred embodiment of the present invention, the crude wash hydrogen peroxide solution is used as the aqueous hydrogen peroxide solution. The preparation of the crude solution is described, for example, in European Patent Application EP 1 122 249 A1.Regarding the term "essentially pure water," see EP1122249A1, page 3, paragraph 10, which is incorporated by reference. Hydrogen peroxide can also be treated before use to remove trace metals, for example, as described in WO2015 / 049327A1.

[0059] It is contemplated that hydrogen peroxide may be prepared in situ in the epoxidation zone from hydrogen and oxygen, preferably in the presence of a suitable noble metal catalyst contained in the epoxidation zone. Suitable noble metal catalysts preferably include one or more of palladium, platinum, silver, gold, rhodium, iridium, ruthenium, and osmium. Preferably, the noble metal catalyst includes palladium. The noble metal catalyst is preferably supported on a support, preferably including one or more of SiO2, Al2O3, BO3, GeO2, Ga2O3, ZrO2, TiO2, MgO, carbon, and one or more zeolites, preferably one or more titanium zeolites. More preferably, the support includes an epoxidation catalyst including a titanium zeolite. When hydrogen peroxide is prepared in situ in the epoxidation zone from hydrogen and oxygen, the reaction mixture includes propylene, hydrogen, oxygen, water, and an organic solvent.

[0060] Epoxidation reaction conditions For epoxidation, a reaction mixture comprising propylene, hydrogen, oxygen, water and an organic solvent is contacted in an epoxidation zone with an epoxidation catalyst comprising a zeolitic material having a framework structure comprising Si, O, and Ti as described with respect to the first aspect of the present invention, or a shaped article according to the fourth aspect, or a shaped article comprising a zeolitic material having a framework structure comprising Si, O, and Ti as described with respect to the first aspect above, and the reaction mixture is subjected to epoxidation reaction conditions in the epoxidation zone to obtain a mixture comprising propylene oxide, water and an organic solvent in the epoxidation zone.

[0061] Generally, there are no particular limitations on the conditions for contact with the epoxidation catalyst in the epoxidation zone, so long as efficient epoxidation of propylene is achieved. Preferably, the epoxidation reaction conditions include trickle-bed conditions or fixed-bed conditions, with fixed-bed conditions being more preferred. Preferably, these conditions are applied in a reactor in which the catalyst is present in a fixed bed. "Trickle-bed conditions" preferably means that the reaction is carried out at a temperature and pressure where the reaction mixture is partially in a liquid phase and partially in a gas phase, and the catalyst is present in a fixed bed. In embodiments involving fixed-bed conditions, the reaction is preferably carried out at a temperature and pressure where the reaction mixture is liquid and no gas phase is present in the epoxidation zone, where two or more liquid phases may be present and the catalyst is present in a fixed bed. Preferably, contact of the reaction mixture with the epoxidation catalyst in the epoxidation zone is carried out at an absolute pressure in the epoxidation zone in the range of 0.5 to 5.0 MPa, preferably 1.5 to 3.0 MPa, and more preferably 1.8 to 2.8 MPa.

[0062] Generally, contacting the reaction mixture with the epoxidation catalyst in the epoxidation zone can be carried out in any suitable manner. Thus, for example, it can be carried out in a batch reactor, or in at least one semi-continuously operated reactor, or in at least one continuously operated reactor. A continuous mode of operation is preferred.

[0063] Preferably, the contact of the reaction mixture with the epoxidation catalyst in the epoxidation zone is carried out in at least one, preferably continuously operating, reactor, such as a tube reactor or tube bundle reactor, which preferably contains at least one cooling jacket surrounding at least one tube. A cooling medium flows through the cooling jacket. The nature of the cooling medium is not particularly limited, provided it is sufficient to adjust the temperature of the epoxidation zone. For example, the cooling medium may contain water and may further contain additives such as aliphatic C2-C5 monoalcohols, aliphatic C2-C5 dialcohols, and mixtures of two or more thereof. Preferably, 90% by weight or more, more preferably 95% by weight or more of the cooling medium is water, based on the total weight of the cooling medium. The temperature of the cooling medium is the temperature of the cooling medium used to adjust the temperature of the reaction mixture in the epoxidation zone. The temperature is preferably adjusted by passing the cooling medium through the cooling jacket. The temperature of the cooling medium is preferably the temperature of the cooling medium before adjusting the temperature of the reaction mixture, preferably the temperature of the cooling medium at the inlet of the cooling jacket.

[0064] Preferably, the contact of the reaction mixture with the epoxidation catalyst in the epoxidation zone is carried out at a temperature in the epoxidation zone ranging from 33 to 73°C, preferably from 38 to 63°C, more preferably from 53 to 63°C. The temperature in the epoxidation zone is measured using ten thermocouples, i.e., ten thermoelectric elements. The epoxidation zone is defined as the region in which the reaction of hydrogen peroxide with propylene to form propylene oxide still occurs in detectable amounts (10 ppm or more propylene oxide). Preferably, the epoxidation zone extends over the entire length of the catalyst bed, i.e., the region in the reactor where the epoxidation catalyst is present (epoxidation zone = catalyst bed). The hot spot, i.e., the region where maximum reaction occurs, is typically located in the first half of the catalyst bed, and preferably at least six of the ten thermoelectric elements are located in the first half of the catalyst bed. The temperature in the epoxidation zone is the average temperature determined from the temperature values ​​measured by all thermoelectric elements located in the first half of the catalyst bed. Typically, the temperature values ​​measured by these thermoelectric elements are different from each other and range from 6 to 10°C. Preferably, the cooling medium temperature is the temperature of the cooling medium at the inlet to the reactor. Preferably, the cooling medium temperature is in the range of 25 to 65°C, more preferably in the range of 30 to 55°C, and even more preferably in the range of 345 to 55°C. A cooling medium temperature in the range of 45 to 55°C is the optimal temperature range. Temperatures below 45°C are associated with the initial stage of the epoxidation reaction and are too low for efficient tempering during the epoxidation reaction. Above 55°C, the decomposition of hydrogen peroxide and the formation of oxygen increase exponentially. With the cooling medium in the range of 45 to 55°C, the temperature of the epoxidation zone is in the optimal range of 53 to 63°C, thereby achieving maximum selectivity and optimal activity.

[0065] Epoxidation Region The reaction mixture is contacted in an epoxidation zone with an epoxidation catalyst comprising a zeolite material having a framework structure comprising Si, O, and Ti according to the first aspect of the present invention, or a shaped article according to the fourth aspect, a shaped article comprising a zeolite material having a framework structure comprising Si, O, and Ti according to the first aspect, and the reaction mixture is subjected to epoxidation reaction conditions in the epoxidation zone, to obtain a mixture comprising propylene oxide, water, and an organic solvent in the epoxidation zone.

[0066] In general, there are no particular restrictions on the design of the epoxidation zone, provided that it is preferably suitable for conducting continuous epoxidation reactions. Preferably, the epoxidation zone comprises one or more epoxidation subzones, and a given epoxidation subzone preferably consists of one or more epoxidation reactors, and there are no particular restrictions on the design of the one or more epoxidation reactors, provided that the reactors are preferably suitable for conducting continuous epoxidation reactions.

[0067] Preferably, the epoxidation zone comprises a first epoxidation subzone consisting of one or more epoxidation reactors A. The term "first epoxidation subzone" as used in this context of the present invention refers to the epoxidation subzone through which the reaction mixture passes, and the epoxidation zone may comprise additional epoxidation subzones disposed downstream of the first epoxidation subzone. When the first epoxidation subzone comprises two or more epoxidation reactors A, it is preferred to arrange the two or more epoxidation reactors A in parallel. In this case, it is preferred to pass the reaction mixture through at least one of the epoxidation reactors A. For example, while passing the reaction mixture through at least one of the epoxidation reactors A, it is possible to shut down at least one of the operating reactors A, for example, for maintenance purposes and / or to regenerate the catalyst contained in at least one of the reactors A. When the first epoxidation subzone comprises two or more epoxidation reactors A, the operating reactors are operated essentially identically, so that given epoxidation conditions are in the same range in all operating epoxidation reactors A. For example, the temperature in the epoxidation zone is in the same range in all reactors.

[0068] The cooling medium temperature is the temperature of the cooling medium used to adjust the temperature of the reaction mixture in the first epoxidation reaction sub-zone, which is preferably adjusted by passing the cooling medium through the cooling jacket of one or more epoxidation reactors A, and the cooling medium temperature is preferably the temperature of the cooling medium before adjusting the temperature of the reaction mixture, preferably the temperature of the cooling medium at the inlet of the cooling jacket of one or more epoxidation reactors A. When the first epoxidation sub-zone comprises two or more epoxidation reactors A, the cooling medium temperature relates to a given reactor A during operation of the first epoxidation sub-zone.

[0069] According to a first preferred embodiment, the epoxidation zone consists of a first epoxidation subzone.

[0070] According to a second preferred embodiment, the epoxidation zone further comprises a second epoxidation subzone consisting of one or more epoxidation reactors B. When the second epoxidation subzone comprises two or more epoxidation reactors B, the two or more epoxidation reactors B are arranged in parallel, with the second epoxidation subzone being arranged downstream of the first epoxidation subzone. In this case, it is preferred that the effluent stream obtained from the first epoxidation subzone, optionally after suitable intermediate treatment, is passed to at least one of the epoxidation reactors B. For example, the effluent stream obtained from the first epoxidation subzone, optionally after suitable intermediate treatment, is passed to at least one of the epoxidation reactors B, while at least one of the reactors B can be shut down, for example, for maintenance purposes and / or to regenerate the catalyst contained in at least one of the reactors B. When the second epoxidation subzone comprises two or more epoxidation reactors B, the reactors in operation are operated essentially identically, so that given epoxidation conditions in all of the epoxidation reactors B in operation are in the same range. In general, it is contemplated that the epoxidation zone will comprise, in addition to the first and second epoxidation subzones, at least one further epoxidation subzone located downstream of the second epoxidation subzone. Preferably, according to a second embodiment, the epoxidation zone consists of the first and second epoxidation subzones.

[0071] Preferably, the temperature of the reaction mixture in the second epoxidation reaction sub-zone is not controlled by passing a cooling medium through the cooling jacket of one or more epoxidation reactors B. More preferably, the second epoxidation sub-zone is an essentially adiabatic epoxidation sub-zone. More preferably, the second epoxidation sub-zone is an adiabatic epoxidation sub-zone.

[0072] In a sixth aspect, the present invention relates to propylene oxide obtained or obtainable from a process according to the fifth aspect.

[0073] The present invention is further illustrated by the following embodiments and combinations of embodiments, as indicated by dependencies and backward references. In particular, it should be noted that in each instance where a range of embodiments is mentioned, the context of a term such as "described in any one of embodiments 1 to 4..." intends to explicitly disclose all embodiments within this range to those skilled in the art, i.e., the wording of this term would be understood by those skilled in the art to be equivalent to "described in any one of embodiments 1, 2, 3, and 4...". Furthermore, it should be clearly noted that the following set of embodiments is not a set of claims that determines the scope of protection, but represents a suitably structured part of the description directed to general and preferred aspects of the present invention.

[0074] 1. A zeolite material having a framework structure comprising Si, O, and Ti, obtained or obtainable from a Ti-containing compound, wherein the Ti-containing compound has an APHA color number of 300 or less.

[0075] 2. A zeolitic material having a framework structure comprising Si, O, and Ti, obtained or obtainable from a Ti-containing compound according to embodiment 1, wherein the Ti-containing compound preferably comprises a Ti-containing alcoholate (alkoxide) selected from the group of Ti(O-alkyl)s, each alkyl group being a branched or unbranched C1-C6 alkyl, more preferably independently selected from the group consisting of tetraethyl orthotitanate (Ti(OEt)), tetraisopropyl orthotitanate (Ti(OPr)), tetra-n-butyl orthotitanate (Ti(OBu)), and mixtures of two or more of these compounds, more preferably tetraethyl orthotitanate (Ti(OEt)), tetraisopropyl orthotitanate (Ti(OPr)), and mixtures of Ti(OEt) and Ti(OPr).

[0076] 3. A zeolitic material having a framework structure comprising Si, O, and Ti, obtained or obtainable from a Ti-containing compound according to embodiment 1 or 2, wherein the Ti-containing compound comprises at least 90% by weight, preferably at least 95% by weight, more preferably at least 96% by weight, more preferably at least 97% by weight, more preferably at least 98% by weight, more preferably at least 99% by weight of Ti-containing alcoholate, based on the total weight of the Ti-containing compound.

[0077] 4. The Ti-containing compound is represented by the general formula (I) in an amount of 10 mass % or less, preferably 5 mass % or less, more preferably 4 mass % or less, more preferably 3 mass % or less, more preferably 2 mass % or less, and more preferably 1 mass % or less, based on the total mass of the Ti-containing compound. [ka] (In the formula, R, R 1 and R 2 are independently selected from the group consisting of a hydrogen atom and a branched or unbranched C1-C6 alkyl, and R 3 is selected from the group consisting of a hydrogen atom, a branched or unbranched C1-C6 alkyl, and a branched or unbranched C1-C6 alkenyl).

[0078] 5. A zeolitic material having a framework structure comprising Si, O, and Ti, obtained or obtainable from a Ti-containing compound according to embodiment 4, wherein the substance of formula (I) is selected from the group consisting of CH3-CH=CH-C(=O)-CH=CH-CH3 (hepta-2,5-dien-4-one), (CH3)2C=CH-C(=O)-CH=C(CH3)2 (phorone, 2,6-dimethyl-hepta-2,5-dien-4-one) and mixtures of hepta-2,5-dien-4-one and 2,6-dimethyl-hepta-2,5-dien-4-one.

[0079] 6. A zeolitic material having a framework structure comprising Si, O, and Ti, obtained or obtainable from a Ti-containing compound according to any one of embodiments 1 to 5, wherein the titanium dioxide content of the zeolitic material is 1.5% by weight or less, preferably 1.2% by weight or less, more preferably 1% by weight or less, more preferably 0.5% by weight or less, based on the total weight of the zeolitic material, and preferably at least 98% by weight of the titanium dioxide is in the anatase form as determined according to Reference Example 7.

[0080] 7. A zeolitic material having a framework structure comprising Si, O, and Ti, obtained or obtainable from the Ti-containing compound according to any one of embodiments 1 to 6, wherein the crystallinity of the zeolitic material, determined according to Reference Example 7, is greater than 85% by weight, preferably in the range of 85 to 95% by weight, more preferably in the range of 87 to 93% by weight, based on the total weight of the zeolitic material.

[0081] 8. A zeolitic material having a framework structure comprising Si, O, and Ti, obtained or obtainable from a Ti-containing compound according to any one of embodiments 1 to 7, wherein the zeolitic material exhibits a propylene oxide activity, determined as described in Reference Example 1, of at least 8.5 wt.%, preferably in the range of 8.5 to 9.5 wt.%, more preferably in the range of 8.5 to 9.0 wt.%.

[0082] 9. The zeolite material has a viscosity of 440-580 mPa s, as determined as described in Reference Example 4. 2 / g, preferably 450 to 570 m 2 9. A zeolitic material having a framework structure comprising Si, O, and Ti, obtained or obtainable from a Ti-containing compound according to any one of embodiments 1 to 8, exhibiting a BET specific surface area in the range of 0.1 μm / g.

[0083] 10. A zeolitic material having a framework structure comprising Si, O, and Ti, obtained or obtainable from the Ti-containing compound according to any one of embodiments 1 to 9, wherein 95 to 100% by weight, preferably 98 to 100% by weight, more preferably 99 to 100% by weight, more preferably 99.5 to 100% by weight, more preferably 99.9 to 100% by weight of the zeolitic material consists of Si, O, Ti, and optionally H.

[0084] 11. A zeolitic material having a framework structure comprising Si, O, and Ti, obtained or obtainable from the Ti-containing compound according to any one of embodiments 1 to 10, wherein the zeolitic material comprises Ti in an amount in the range of 0.2 to 5% by weight, preferably in the range of 0.5 to 4% by weight, more preferably in the range of 1.0 to 3% by weight, more preferably in the range of 1.2 to 2.5% by weight, more preferably in the range of 1.4 to 2.2% by weight, calculated as elemental Ti and based on the total weight of the zeolitic material.

[0085] 12. ABW, ACO, AEI, AEL, AEN, AET, AFG, AFI, AFN, AFO, AFR, AFS, AFT, AFX, AAN, AAN APC, APD, AST, ASV, ATN, ATO, ATS, ATT, ATV, AWO, AWW, BCT, BEA, BEC, BIK, BOG, BPH, BRE, CAN CAS, CDO, CFI, CGF, CGS, CHA, CHI, CLO, CON, CZP, DAC, DDR, DFO, DFT, DOH, DON, EAB, EDI, EMT EPI、ERI、ESV、ETR、EUO、FAU、FER、FRA、GIS、GIU、GME、GON、GOO、HEU、IFR、ISV、ITE、ITH、ITQITW, IWR, IWW, JBW, KFI, LAU, LEV, LIO, LOS, LOV, LTA, LTL, LTN, MAR, MAZ, MCM-22(S), MCM-36, MCM-56, MEI, MEL, MEP, MER, MIT-1, MMFI, MFS, MON, MOR, MSE, MSO, MTF, MTN, MTT, MTW, MWW, NAB, NAT, NEES, NON, NPO, OBW, OFF, OSI, OSO, PAR, PAU, PHI, PON, RHO, RON, RRO, RSN, RTE, RTH, RUT, RWR, RWY, SAO, SAS, SAT, SAV, SBE, SBS, SBT, SFE, SFF, SFG, SFH, SFN SFO, SGT, SOD, SSY, STF, STI, STT, TER, THO, TON, TSC, UEI, UFI, UOZ, USI, UTL, VET, VFI, VNI, VSV, WEI, WEN, YUG, ZON 12. A zeolitic material having a framework structure comprising Si, O, and Ti obtained or obtainable from the Ti-containing compound according to any one of embodiments 1 to 11, wherein the zeolitic material is a titanium zeolite having an SVR framework, an SVY framework, or a mixed structure of two or more of these framework types; more preferably, the zeolitic material having a framework structure comprising Si, O, and Ti is an MFI framework type, an MEL framework type, an MWW framework type, an MCM-22(S) framework type, an MCM-56 framework type, an IEZ-MWW framework type, an MCM-36 framework type, an ITQ framework type, a BEA framework type, an MOR framework type, or a mixed structure of two or more of these framework types; more preferably, the titanium zeolitic material having an MFI framework type or an MWW framework type; more preferably, the zeolitic material having a framework structure comprising Si, O, and Ti has framework type MFI; more preferably, the zeolitic material having a framework structure comprising Si, O, and Ti is titanium silicalite-1 (TS-1).

[0086] 13. A Ti-containing compound having an APHA color number of 300 or less, comprising a Ti-containing alcoholate preferably selected from the group of Ti(O-alkyl)4, wherein each alkyl group is independently selected from branched or unbranched C1-C6 alkyl, more preferably from the group consisting of tetraethyl orthotitanate (Ti(OEt)4), tetraisopropyl orthotitanate (Ti(OPr)4), tetra-n-butyl orthotitanate Ti(OBu)4 and mixtures of two or more of these compounds, more preferably from the group of tetraethyl orthotitanate (Ti(OEt)4), tetraisopropyl orthotitanate (Ti(OPr)4) and mixtures of Ti(OEt)4 and Ti(OPr)4.

[0087] 14. The Ti-containing compound having an APHA color number of 300 or less according to embodiment 13, wherein the Ti-containing compound comprises at least 90% by weight, preferably at least 95% by weight, more preferably at least 96% by weight, more preferably at least 97% by weight, more preferably at least 98% by weight, and more preferably at least 99% by weight of Ti-containing alcoholate, based on the total weight of the Ti-containing compound.

[0088] 15. The Ti-containing compound is a compound represented by formula (I) in an amount of 10% by mass or less, preferably 5% by mass or less, more preferably 4% by mass or less, more preferably 3% by mass or less, more preferably 2% by mass or less, and more preferably 1% by mass or less, based on the total mass of the Ti-containing compound. [ka] (In the formula, R, R 1 and R 2 are independently selected from the group consisting of a hydrogen atom and a branched or unbranched C1-C6 alkyl, and R 3 is selected from the group consisting of a hydrogen atom, a branched or unbranched C1-C6 alkyl, and a branched or unbranched C1-C6 alkenyl.

[0089] 16. The Ti-containing compound having an APHA color number of 300 or less according to any one of embodiments 13 to 15, wherein the substance of formula (I) is selected from the group consisting of CH3-CH=CH-C(=O)-CH=CH-CH3 (hepta-2,5-dien-4-one), (CH3)2C=CH-C(=O)-CH=C(CH3)2 (phorone=2,6-dimethyl-hepta-2,5-dien-4-one), and mixtures of hepta-2,5-dien-4-one and 2,6-dimethyl-hepta-2,5-dien-4-one.

[0090] 17. Use of a Ti-containing compound having an APHA color number of 300 or less as defined in any one of embodiments 13 to 16 for the preparation of a zeolitic material having a framework structure comprising Si, O, and Ti as defined in any one of embodiments 1 to 12.

[0091] 18. A method for producing a zeolitic material having a framework structure comprising Si, O, and Ti, wherein the zeolitic material having a framework structure comprising Si, O, and Ti is produced from a Ti-containing compound having an APHA color number of 300 or less, the Ti-containing compound being as defined in any one of embodiments 13 to 16.

[0092] 19. A molded article comprising a zeolitic material having a framework structure comprising Si, O, and Ti according to any one of embodiments 1 to 12.

[0093] 20. The molded article of embodiment 19, which exhibits a tortuosity parameter for water, determined as described in Reference Example 5, of less than 4, preferably in the range of 1.0 to 2.5, more preferably in the range of 1.3 to 2.0, more preferably in the range of 1.40 to 1.80, more preferably in the range of 1.50 to 1.75, more preferably in the range of 1.55 to 1.70.

[0094] 21. The molded article of embodiment 19 or 20, wherein the pore volume of the molded article, determined according to DIN 66133:1993-06, is in the range of 0.1 to 1.5 ml / g.

[0095] 22. Use of the shaped article according to any one of embodiments 19 to 21 as an adsorbent, absorbent, catalyst or catalyst component, preferably as a catalyst or catalyst component, more preferably as a Lewis acid catalyst or Lewis acid catalyst component, as an isomerization catalyst or isomerization catalyst component, as an oxidation catalyst or oxidation catalyst component, as an aldol condensation catalyst or aldol condensation catalyst component, or as a Prins reaction catalyst or Prins reaction catalyst component.

[0096] 23. The use according to embodiment 22 as an oxidation catalyst or as an oxidation catalyst component, preferably as an epoxidation catalyst or as an epoxidation catalyst component, more preferably as an epoxidation catalyst.

[0097] 24. The use according to embodiment 23 for the epoxidation reaction of an organic compound having at least one C-C double bond, preferably a C2-C10 alkene, more preferably a C2-C5 alkene, more preferably a C2-C4 alkene, more preferably a C2 or C3 alkene, more preferably propene, more preferably for the epoxidation of propene using hydrogen peroxide as the oxidant, more preferably for the epoxidation of propene using hydrogen peroxide as the oxidant in a solvent comprising an alcohol, preferably methanol.

[0098] 25. A process for the oxidation of an organic compound, preferably for the epoxidation of an organic compound, more preferably for the epoxidation of an organic compound having at least one C-C double bond, preferably a C2-C10 alkene, more preferably a C2-C5 alkene, more preferably a C2-C4 alkene, more preferably a C2 or C3 alkene, more preferably propene, comprising contacting the organic compound, preferably in a continuous mode, with a catalyst comprising the shaped article of any one of embodiments 19 to 21.

[0099] 26. The method of embodiment 25, wherein hydrogen peroxide is used as the oxidizing agent and the oxidation reaction is preferably carried out in a solvent, more preferably in a solvent comprising an alcohol, preferably methanol.

[0100] 27. A method for producing propylene oxide, comprising reacting propene, preferably in a continuous mode, with hydrogen peroxide in a solvent in the presence of a catalyst comprising the shaped article of any one of embodiments 19 to 21 to obtain propylene oxide.

[0101] 28. The method for producing propylene oxide according to embodiment 27, wherein the reaction of propene with hydrogen peroxide in a solvent in the presence of a catalyst is carried out in the epoxidation zone at an absolute pressure in the epoxidation zone in the range of 0.5 to 5.0 MPa, preferably in the range of 1.5 to 3.0 MPa, more preferably in the range of 1.8 to 2.8 MPa.

[0102] 29. The method for producing propylene oxide according to embodiment 27 or 28, wherein the reaction of propene with hydrogen peroxide in a solvent in the presence of a catalyst is carried out in an epoxidation zone at a temperature in the epoxidation zone ranging from 33 to 73°C, preferably from 38 to 63°C, more preferably from 53 to 63°C.

[0103] 30. The method for producing propylene oxide according to any one of embodiments 27 to 29, wherein a cooling medium is used to adjust the temperature of the epoxidation zone, and the temperature of the cooling medium is preferably in the range of 25 to 65°C, preferably in the range of 30 to 55°C, more preferably in the range of 345 to 55°C.

[0104] 31. The method for producing propylene oxide according to any one of embodiments 27 to 30, wherein the mass ratio (w / w) of propylene to hydrogen peroxide is in the range of 1:1 to 6:1, preferably in the range of 1:1 to 2:1 or in the range of 4:1 to 5:1.

[0105] 32. The method for producing propylene oxide according to any one of embodiments 27 to 31, wherein the mass ratio (w / w) of solvent:hydrogen peroxide is in the range of 15:1 to 5:1, preferably in the range of 12:1 to 6:1, and more preferably in the range of 11:1 to 8:1.

[0106] 33. The method for producing propylene oxide according to any one of embodiments 27 to 32, wherein the mass ratio (w / w) of solvent:propylene in the reaction mixture is in the range of 10:1 to 1:0.1, preferably in the range of 9:1 to 1:1, more preferably in the range of 9:1 to 7:1 or in the range of 1.5:1 to 1:1.

[0107] 34. The method for producing propylene oxide according to any one of embodiments 27 to 33, wherein the epoxidation reaction conditions comprise trickle-bed conditions.

[0108] 35. The method for producing propylene oxide according to any one of embodiments 27 to 33, wherein the epoxidation reaction conditions comprise fixed bed conditions.

[0109] 36. The method of any one of embodiments 27 to 35, wherein the solvent is an organic solvent, preferably an organic epoxidation solvent, more preferably selected from the group consisting of alcohol, acetonitrile, tert-butanol, propionitrile, and mixtures of two or more thereof, more preferably selected from the group consisting of alcohol, acetonitrile, and mixtures of alcohol and acetonitrile, more preferably the solvent comprises at least an alcohol, more preferably the solvent comprises at least methanol.

[0110] 37. Propylene oxide obtained or obtainable by the method of any one of embodiments 27 to 36.

[0111] It should be clearly noted that the set of embodiments described above represents a suitably structured part of the description directed to general and preferred aspects of the present invention, rather than a set of claims that determines the scope of protection.

[0112] The present invention is further illustrated by the following Reference Examples, Comparative Examples and Examples. [Example]

[0113] Reference Example 1: Determination of Propylene Oxide Activity and Pressure Drop Rate (PO Test) To evaluate the potential suitability of the powders described in detail below as catalysts for the epoxidation of propene in a PO test, the powders were tested in a glass autoclave by reacting propene with aqueous hydrogen peroxide (30% by weight) to produce propylene oxide in a preliminary test procedure. Specifically, 0.5 g of each powder was placed in a glass autoclave together with 45 ml of methanol or 45 ml of acetonitrile, which was cooled to -25°C. 20 ml of liquid propene was pressurized into the glass autoclave, which was heated to 0°C. At this temperature, 18 g of aqueous hydrogen peroxide (30% by weight in water) was placed in the glass autoclave. After a reaction time of 5 hours at 0°C, the mixture was heated to room temperature (25°C), and the propylene oxide content of the liquid phase was analyzed by gas chromatography. The propylene oxide content (in mass%) of the liquid phase was the result of the PO test, i.e., the propylene oxide activity of the powder.

[0114] Reference Example 2: Determination of propylene epoxidation catalyst performance In a continuous epoxidation reactor, a vertically arranged tubular reactor (length: 1.4 m, outer diameter: 10 mm, inner diameter: 4 mm, material: stainless austenitic steel, type 1.4571) equipped with a cooling jacket for thermal stabilization was loaded with 15 g of strand-form TS-1 catalyst extrusions, as described in each of the following Examples and Comparative Examples. The area in the reactor covered by the extrusions is referred to as the catalyst bed. The remaining reactor volume was filled with an inert material (steatite spheres, 2 mm diameter) to a height of approximately 5 cm at the bottom of the reactor, and the remainder at the top of the reactor. The temperature in the epoxidation zone (= catalyst bed) was measured using 10 thermocouples (10 thermoelements, each made of stainless austenitic steel, type 1.4571). Six of the 10 thermoelements were located in the first half of the catalyst bed.

[0115] Feed streams were provided for all starting materials, methanol, propylene, and hydrogen peroxide. The starting materials were passed through the reactor at the following flow rates: methanol (49 g / h), hydrogen peroxide (9 g / h, used as an aqueous hydrogen peroxide solution with a hydrogen peroxide content of 40% by weight), and propylene (7 g / h, polymer grade).

[0116] The average temperature in the epoxidation zone was adjusted to a range of 60-70°C via a cooling medium passed through a cooling jacket, so that the hydrogen peroxide conversion, determined based on the reaction mixture leaving the reactor, was essentially constant at 90%. The pressure in the reactor was kept constant at 21 bar (abs), and the reaction mixture, excluding the fixed-bed catalyst, consisted of a single liquid phase.

[0117] The reactor effluent downstream of the pressure control valve was collected, metered, and analyzed. The organic components were analyzed by two separate gas chromatographs. The hydrogen peroxide content was determined colorimetrically using the titanyl sulfate method. The selectivity of propylene oxide to hydrogen peroxide (S(H2O2) vs. PO) was determined according to equation (1):

number

[0118] Reference Example 3: Determination of N2 adsorption / desorption isotherms Nitrogen adsorption / desorption isotherms (N adsorption isotherms) were determined at 77 K according to the method disclosed in DIN 66131:1993-07. N adsorption isotherms were measured at liquid nitrogen temperature using a Micrometrics ASAP2020M and Tristar system.

[0119] Reference Example 4: Determination of BET specific surface area The BET specific surface area was determined by nitrogen physical adsorption at 77 K according to the method disclosed in DIN 66131:1993-07. To determine the BET specific surface area, N adsorption isotherms were measured at liquid nitrogen temperature using a Micrometrics ASAP2020M and Tristar system, as in Reference Example 3.

[0120] Reference Example 5: Determination of tortuosity parameters for water PFG NMR allows for the non-destructive study of thermal molecular motion in free gases and liquids, in macro- and supramolecular solutions, and of adsorbed molecules in porous systems. The principles and applications are described in US2007 / 0099299A1. The tortuosity factor was calculated from the diffusion coefficient obtained by NMR as follows: The tortuosity factor of a porous material is calculated by multiplying the self-diffusion coefficient (D eff ) and the self-diffusion coefficient of the free liquid (D0) according to equation (2) (see S. Kolitcheff, E. Jolimaitre, A. Hugon, J. Verstraete, M. Rivallan, P. L. Carrette, F. Couenne and M. Tayakout-Fayolle, Catal. Sci. Technol., 2018, 8, 4537; and F. Elwinger, P. Pourmand, and I. Furo, J. Phys. Chem. C. 2017, 121, 13757-13764).

[0121]

number

[0122] The free diffusion coefficient of water is 2.02 x 10 at 20°C. -9 m 2 s -1 (See M. Holz, SR Heil and A. Sacco. Phys. Chem. Chem. Phys., 2000, 2, 4740-4742).

[0123] Determination of diffusion coefficients by NMR For NMR analysis, samples were prepared by drying a small amount (0.05–0.2 g) of the shaped catalyst overnight in an NMR tube under vacuum at T > 350 °C. The sample was then loaded with nanopure water (Millipore Advantage A10) via a vacuum line to 90% of the catalyst support's pore volume (determined by Hg-porosimetry). The loaded sample was then flame-sealed in the tube and allowed to sit overnight before measurement.

[0124] D for water in the catalyst material eff NMR analysis to determine β was performed using a Bruker Avance III NMR spectrometer at 20 °C and 1 bar, with a 400 MHz 1H resonance frequency. A Bruker Diff50 probehead was used with a Bruker Great 60A gradient amplifier. A temperature of 20 °C was maintained with a water-cooled gradient coil. The pulse program used for PFG NMR self-diffusion analysis was stimulated spin echo with a pulsed magnetic field gradient according to Figure 1b of US2007 / 0099299A1. For each sample, spin echo decay curves were measured at different diffusion times (between 20 and 100 ms) with stepwise increases in magnetic field gradient strength (up to a maximum gmax = 3 T / m). The gradient pulse length was 1 ms. The spin echo decay curves were fitted to Equation 6 of US2007 / 0099299A. The slope of each line corresponded to the diffusion coefficient. The average diffusion coefficient over all diffusion times was used to calculate the tortuosity of each catalyst support according to Equation (2) above. The slope of each line corresponded to the diffusion coefficient.

[0125] Reference Example 6: Preparation of molded articles using colloidal silica binder precursor Shaping: Particles of the zeolite materials of Examples 3 and 4 and Comparative Examples 1 and 2 below (105.3 g) were mixed with carboxymethylcellulose (4.0 g; Walocel™, Mw=15,000 g) in a kneader for 5 minutes. Polystyrene aqueous dispersion (100.7 g; 33.7 g polystyrene) was then added successively. After 10 minutes, polyethylene oxide (1.33 g) was added. After 10 minutes, 70 g of Ludox® AS40 (40% by weight silica in water) was added. After another 10 minutes, 10 ml of water was added, and after another 5 minutes, another 10 ml of water was added. The total kneading time was 40 minutes. The moldable mass obtained from the kneading was extruded at a pressure of 130 bar through a matrix with circular holes 1.9 mm in diameter. The resulting strands were dried in an oven at a temperature of 120°C in air for 4 hours and calcined at a temperature of 490°C in air for 5 hours.

[0126] Water treatment: 36 g of these strands were mixed with 180 g of deionized water in four portions of 9 g each. The resulting mixture was heated in an autoclave at 145°C for 8 hours. The resulting water-treated strands were then separated and sieved through a 0.8 mm sieve. The resulting strands were washed with deionized water and exposed to a nitrogen stream at ambient temperature. Subsequently, each washed strand was dried in air at 120°C for 4 hours and then calcined in air at 450°C for 2 hours.

[0127] Reference Example 7: Powder X-ray diffraction and determination of crystallinity Powder X-ray diffraction (PXRD) data were collected using a diffractometer (D8 Advance Series II, Bruker AXS GmbH) equipped with a LYNXEYE detector operated with a copper anode X-ray tube at 40 kV and 40 mA, Bragg-Brentano geometry, and an air scattering shield was used to reduce air scattering.

[0128] Crystallinity calculation: The crystallinity of the samples was measured using the software DIFFRAC.EVA provided by Bruker AXS GmbH, Karlsruhe. The method is described in the user manual, page 121. Default parameters were used for the calculation.

[0129] Calculation of phase composition: The phase composition was calculated on the raw data using the modeling software DIFFRAC.TOPAS provided by Bruker AXS GmbH, Karlsruhe. Diffraction patterns were simulated using the identified crystal structures of the phases, the instrumental parameters, and the crystallite sizes of the individual phases. This was then fitted to the data in addition to a function that models the background intensity.

[0130] Data collection: Samples were homogenized in a mortar and then pressed into a standard flat sample holder provided by Bruker AXS GmbH for Bragg-Brentano geometry data collection. A glass plate was used to compress and flatten the sample powder to achieve a flat surface. Data were collected from an angular range of 2 to 70° 2θ with a step size of 0.02° 2θ, and the variable divergence slit was set at an angle of 0.1°. The crystalline content represents the intensity of the crystalline signal relative to the total scattered intensity (DIFFRAC.EVA User Manual, Bruker AXS GmbH, Karlsruhe).

[0131] Example 1: Determination of APHA color and organic impurities A) Determination of organic substances in tetraethyl orthotitanate (Ti(OEt)4) of different APHA colors and tetraisopropyl orthotitanate (Ti(OPr)4) of different APHA colors The organic matter content of Ti(OEt)4) samples with different APHA color values ​​was analyzed. The APHA color was determined according to DIN EN ISO 6271:2016-05 (Hazen color value) using a Lico® 620 colorimeter.

[0132] Before quantifying the organic impurities, the precipitate (TiO) formed over time was filtered. Quantification was performed by HPLC / CE using DNPH (2,4-dinitrophenylhydrazine) derivatization. Column: Symmetry Shield RP18, 5 μm, 2.1 × 150 mm, water; 45 °C; 0.4 ml / min; runtime: 45 min; UV detector. The identity of the material in the organic phase was double-checked by GC / MS (Column: Restek #13623; RXI-5sil MS, 30 m × 0.25 mm × 0.25 μm; inlet temperature: 200 °C; temperature program: 1) 35 °C for 7 min, 2) ramp to 220 °C at 8 °C / min). The results are shown in Table 1 below.

[0133] [Table 1]

[0134] Acetaldehyde and crotonaldehyde were clearly identified by comparison with database spectra; quantification of the sample with an APHA color number of 68 was performed by HPLC / CE using DNPH (2,4-dinitrophenylhydrazine) derivatization; column: Symmetry Shield RP18, 5 μm, 2.1 × 150 mm, water; 45°C; 0.4 ml / min; runtime: 45 min; UV detector. The respective amounts were as follows: Acetaldehyde: 55 mg / kg (55 ppm by mass) Crotonaldehyde: 12 mg / kg (12 ppm by mass).

[0135] The organic matter content of tetraisopropyl orthotitanate (Ti(OPr)4) samples with different APHA color values ​​was analyzed. The APHA color was determined according to DIN EN ISO 6271:2016-05 (Hazen color value) using a Lico® 620 colorimeter.

[0136] The precipitate (TiO2) formed over time was filtered before quantifying the organic impurities. The organic phase was then analyzed by GC / MS (column: Restek #13623; RXI-5silMS, 30 m x 0.25 mm x 0.25 μm; inlet temperature: 200 °C; temperature program: 1) 35 °C for 7 min, 2) to 220 °C at 8 °C / min), and the results are shown in Table 2 below.

[0137] [Table 2]

[0138] Acetone and 4-methyl-3-penten-2-one were clearly identified by comparison with database spectra. Quantitation of a sample with an APHA color number of 75 was performed by HPLC / CE using DNPH (2,4-dinitrophenylhydrazine) derivatization; column: Symmetry Shield RP18, 5 μm, 2.1 × 150 mm, water; 45°C; 0.4 ml / min; runtime: 45 min; UV detector. The amounts of each were as follows: Acetone: 23 mg / kg (23 ppm) 4-Methyl-3-penten-2-one: 5 mg / kg (5 ppm).

[0139] B) APHA color determination of tetraethyl orthotitanate (Ti(OEt)4) on different tetraethyl orthotitanate probes The APHA colour of the different tetraethyl orthotitanate (Ti(OEt)4) probes was determined according to DIN EN ISO6271:2016-05 (Hazen colour values) using a Lico® 620 colourimeter.

[0140] A fresh, visually clear tetraethyl orthotitanate probe (tetraethyl orthotitanate purchased from Merck) was used as a reference. The results are shown in Table 3.

[0141] [Table 3]

[0142] C) APHA color determination of tetrabutyl orthotitanate on different (Ti(OBu)4) probes The APHA colour of the different tetrabutyl orthotitanate (Ti(OBu)4) probes was determined according to DIN EN ISO6271:2016-05 (Hazen colour values) using a Lico® 620 colourimeter.

[0143] A fresh, visually clear tetrabutyl orthotitanate probe (tetraethyl orthotitanate purchased from Merck) was used as a reference. The results are shown in Table 4.

[0144] [Table 4]

[0145] Example 2: Synthesis of TS1-1 catalyst Titanium silicalite-1 (TS-1) powder was prepared according to the following recipe:

[0146] Initial mass: Tetraethyl orthosilicate 500g Tetraethyl orthotitanate (see Example 1) 15 g Tetrapropylammonium hydroxide (40% by weight aqueous solution) 220g 300g deionized water.

[0147] Tetraethyl orthosilicate and tetraethyl orthotitanate (reference from Example 1) with an APHA color number of 102 were added to a four-neck flask. Deionized water and aqueous tetrapropylammonium hydroxide were added at 200 L / min with stirring. The pH value of the solution, determined by a pH electrode, was 13.54. The solution was hydrolyzed at room temperature (25°C) for 60 minutes, and the temperature was raised to 60°C.

[0148] The ethanol formed during the reaction was removed by distillation until the temperature of the flask bath reached 95°C. The amount of ethanol removed was 547 g, and the pH in the bath was 11.98. The remaining gel was stirred until the temperature reached 40°C. 530 g of deionized water was added with stirring, and the pH of the resulting solution was measured with a pH electrode to be 11.52.

[0149] The resulting solution was then transferred to an autoclave and heated with stirring to 175° C. Crystallization was carried out at 175° C. for 16 hours under autogenous pressure with stirring (rotation speed 200 U / min, torque in the range of 50-70 N / cm, pressure in the range of 9-10 bar).

[0150] The suspension containing titanium silicalite-1 crystals was transferred to another container and diluted with deionized water in a 1:1 volume ratio at 200 U / min with stirring in a Teflon U-shaped mixer. Approximately 215.8 g of a 10% by weight HNO3 aqueous solution was then added so that the pH, determined with a pH electrode, was reduced to 7, followed by filtration (porcelain suction, blue band filter). The filter cake was washed three times with 1000 ml of deionized water each, then dried in a ventilated muffle at 120 °C for 4 hours, and then calcined in air at 490 °C for 5 hours (heating rate 2 °C / min).

[0151] Zeolitic material in the form of a powder was obtained in an amount of 88% by weight based on the weight of the initial tetraethyl orthotitanate. Based on the crystallinity and phase composition data determined according to Reference Example 7, 100% by weight of the obtained particles were of the TS-1 structure (anatase content (TiO) 0% by weight), and showed a Ti content, calculated as elemental Ti, of 2.0% by weight and a Si content, calculated as elemental Si, of 42% by weight, based on the total weight of the obtained particles. The BET specific surface area of ​​the powder was 563 m, as determined according to Reference Example 4. 2 / g.

[0152] The absorbance of the powders in diffusely reflected light was measured using a UV / VIS / NIR spectrophotometer Lambda 950 equipped with a 150 mm integrating sphere (Ulbrichtkugel) indicating the lamp switching point. Based on the %R spectra, a Kubelka-Munk transformation (KM) was performed, and the results are shown in Figure 2. No significant bands were observed above 330 nm (approximately 330 nm to approximately 350 nm), indicating the absence of significant amounts of anatase.

[0153] The moldings were prepared according to Reference Example 6.

[0154] Example 3: Synthesis of TS1-1 catalyst Titanium silicalite-1 (TS-1) powder was prepared according to the following recipe:

[0155] Initial mass: Tetraethyl orthosilicate 500g Tetraethyl orthotitanate (Probe No. 1 from Example 1) 15 g Tetrapropylammonium hydroxide (40% by weight aqueous solution) 220g 300g deionized water.

[0156] Tetraethyl orthosilicate and tetraethyl orthotitanate (probe #1 from Example 1) with an APHA color number of 251 were added to a four-neck flask. Deionized water and aqueous tetrapropylammonium hydroxide were added at 200 L / min with stirring. The pH value of the solution, determined by a pH electrode, was 13.56. Further steps were carried out as in Example 2.

[0157] After calcination, zeolitic material in the form of a powder was obtained at 93% by weight based on the weight of the initial tetraethyl orthotitanate. Based on the crystallinity and phase composition data determined according to Reference Example 7, 100% of the obtained particles were of the TS-1 structure (anatase content (TiO2) 0% by weight). The particles exhibited a Ti content, calculated as elemental Ti, of 2.0% by weight, and a Si content, calculated as elemental Si, of 44% by weight, based on the total weight of the obtained particles. The BET specific surface area of ​​the powder was 462 m, determined according to Reference Example 4.2 / g.

[0158] The absorbance of the powder in diffusely reflected light was determined as in Example 2, and the results obtained from the Kubelka-Munk transformation (KM) are shown in Figure 2. No significant bands were observed above 330 nm (approximately 330 nm to approximately 350 nm), suggesting the absence of significant amounts of anatase.

[0159] Mouldings were prepared according to Reference Example 6. The strands obtained after water treatment and calcination had a tortuosity parameter for water of 1.6, determined according to Reference Example 5. The porosity / pore volume was 0.92 ml / g, determined by Hg porosimetry according to DIN 66133:1993-06.

[0160] Example 4: Synthesis of TS1-1 catalyst Titanium silicalite-1 (TS-1) powder was prepared according to the following recipe:

[0161] Initial mass: Tetraethyl orthosilicate 500g Tetraethyl orthotitanate (Probe No. 2 from Example 1) 15 g Tetrapropylammonium hydroxide (40% by weight aqueous solution) 220g 300g deionized water.

[0162] Tetraethyl orthosilicate and tetraethyl orthotitanate (probe #2 from Example 1) with an APHA color number of 300 were added to a four-neck flask. Deionized water and aqueous tetrapropylammonium hydroxide were added at 200 L / min with stirring. The pH value of the solution, determined by a pH electrode, was 13.50. Further steps were carried out according to Example 2.

[0163] After calcination, a zeolitic material in the form of a powder was obtained at 91% by weight based on the weight of the initial tetraethyl orthotitanate. Based on the crystallinity and phase composition data determined according to Reference Example 7, 99.0% by weight of the resulting particles were TS-1 structure, and 1% by weight was anatase, based on the total weight of the resulting particles. The particles exhibited a Ti content of 2.0% by weight, calculated as elemental Ti, and a Si content of 45% by weight, based on the total weight of the resulting particles. The BET specific surface area of ​​the powder was 437 m, as determined according to Reference Example 4. 2 / g.

[0164] The absorbance of the powder in diffusely reflected light was determined as in Example 2, and the results obtained from the Kubelka-Munk transformation (KM) are shown in Figure 2. A significant band was observed above 330 nm (from about 330 nm to about 350 nm), suggesting the presence of a significant amount of anatase.

[0165] Mouldings were prepared according to Reference Example 6. The strands obtained after water treatment and calcination had a tortuosity parameter for water of 2.2, determined according to Reference Example 5. The porosity / pore volume was 0.84 ml / g, determined by Hg porosimetry according to DIN 66133:1993-06.

[0166] Comparative Example 1: Synthesis of TS1-1 catalyst Titanium silicalite-1 (TS-1) powder was prepared according to the following recipe:

[0167] Initial mass: Tetraethyl orthosilicate 500g Tetraethyl orthotitanate (probe no. 3 from Example 1) 15 g Tetrapropylammonium hydroxide (40% by weight aqueous solution) 220g 300g deionized water.

[0168] Tetraethyl orthosilicate and tetraethyl orthotitanate (probe #3 from Example 1) with an APHA color number >1000 were added to a four-neck flask. Deionized water and aqueous tetrapropylammonium hydroxide were added at 200 L / min with stirring. The pH value of the solution, determined by a pH electrode, was 13.48. Further steps were carried out as in Example 2.

[0169] After calcination, zeolitic material in the form of a powder was obtained at 92% by weight based on the weight of the initial tetraethyl orthotitanate. Based on the crystallinity and phase composition data determined according to Reference Example 7, 98.7% by weight of the resulting particles was TS-1 structure, and 1.3% by weight was anatase, based on the total weight of the resulting particles. The particles exhibited a Ti content of 2.0% by weight, calculated as elemental Ti, and a Si content of 43% by weight, based on the total weight of the resulting particles. The BET specific surface area of ​​the powder was 455 m, determined according to Reference Example 4. 2 / g.

[0170] The absorbance of the powder in diffusely reflected light was determined as in Example 2, and the results obtained from the Kubelka-Munk transformation (KM) are shown in Figure 2. A significant band was observed above 330 nm (from about 330 nm to about 350 nm), suggesting the presence of a significant amount of anatase.

[0171] Mouldings were prepared according to Reference Example 6. The strands obtained after water treatment and calcination had a tortuosity parameter for water of 1.4, determined according to Reference Example 5. The porosity / pore volume was 0.91 ml / g, determined by Hg porosimetry according to DIN 66133:1993-06.

[0172] Comparative Example 2: Synthesis of TS1-1 catalyst Titanium silicalite-1 (TS-1) powder was prepared according to the following recipe:

[0173] Initial mass: Tetraethyl orthosilicate 500g Tetraethyl orthotitanate (Probe No. 4 from Example 1) 15 g Tetrapropylammonium hydroxide (40% by weight aqueous solution) 220g 300g deionized water.

[0174] Tetraethyl orthosilicate and tetraethyl orthotitanate (probe #4 from Example 1) with an APHA color number >1000 were added to a four-neck flask. Deionized water and aqueous tetrapropylammonium hydroxide were added at 200 L / min with stirring. The pH value of the solution measured by a pH electrode was 13.48. Further steps were carried out according to Example 2.

[0175] After calcination, a zeolitic material in the form of a powder was obtained at 89% by weight based on the weight of the initial tetraethyl orthotitanate. Based on the crystallinity and phase composition data determined according to Reference Example 7, 98.5% by weight of the resulting particles were of the TS-1 structure, and 1.5% by weight was anatase, based on the total weight of the resulting particles. The particles exhibited a Ti content of 2.0% by weight, calculated as elemental Ti, and a Si content of 44% by weight, based on the total weight of the resulting particles. The BET specific surface area of ​​the powder was 461 m, as determined according to Reference Example 4. 2 / g.

[0176] The XRD spectrum of the obtained solid is shown in FIG.

[0177] The absorbance of the powder in diffusely reflected light was determined as in Example 2, and the results obtained from the Kubelka-Munk transformation (KM) are shown in Figure 2. A significant band was observed above 330 nm (from about 330 nm to about 350 nm), suggesting the presence of a significant amount of anatase.

[0178] Mouldings were prepared according to Reference Example 6. The strands obtained after water treatment and calcination had a tortuosity parameter for water of 1.3, determined according to Reference Example 5. The porosity / pore volume was 0.98 ml / g, determined by Hg porosimetry according to DIN 66133:1993-06.

[0179] Example 6: Synthesis of TiMWW catalyst A deboronated zeolitic material having an MWW framework type was prepared according to Example 1 of WO 2013 / 117537 A1. The resulting spray-dried deboronated zeolitic material of framework type MWW (deboronated MWW) had a B content of 0.08 wt.%, a Si content of 42 wt.%, and a TOC content of 0.23 wt.%.

[0180] A titanium zeolite having the MWW framework type (TiMWW) in powder form was prepared according to the following recipe:

[0181] Initial mass: Piperidine 303.1g Tetrabutyl orthotitanate 43.13g Deboronated MWW 220g 821.8g deionized water.

[0182] Piperidine was added to a beaker containing 500 g of deionized water and stirred at 200 rpm for 10 minutes. Tetrabutyl orthotitanate (probe #5 from Example 1) with an APHA color number of 171 was added with stirring. After 15 minutes of stirring, 321.8 g of demineralized water was added, followed by an additional 15 minutes of stirring. The deboronated MWW was added, and the suspension was stirred for 60 minutes. The suspension was then transferred to a 2.5 liter autoclave and heated at 170°C with stirring for 48 hours. After cooling, the suspension was filtered through a porcelain filter, washed with deionized water, and the filter cake was dried at 120°C for 10 hours. 90 g of the dried material was added to a four-neck round-bottom flask containing 1800 g of 10% HNO3 solution with stirring (200 rpm). The suspension was heated to 100°C under reflux for 1 hour, cooled, filtered through a porcelain filter, and washed three times with 1000 ml of deionized water. The filter cake was dried at 120°C for 4 hours and the powder was calcined at 550°C for 5 hours (heating rate 2°C / min).

[0183] After calcination, a zeolitic material (TiMWW) was obtained in powder form. The crystallinity was 82% as determined by Reference Example 7. The particles exhibited a Ti content of 2.1% by weight and a Si content of 41% by weight, calculated as elemental Ti, based on the total mass of the particles obtained.

[0184] The absorbance of the powder in diffusely reflected light was determined as in Example 2, and the results obtained from the Kubelka-Munk transformation (KM) are shown in Figure 3. No significant bands were observed above 330 nm (approximately 330 nm to approximately 350 nm), which may indicate the presence of significant amounts of anatase.

[0185] Comparative Example 3: Synthesis of TiMWW catalyst A deboronated zeolitic material having an MWW framework type was prepared according to Example 1 of WO 2013 / 117537 A1. The resulting spray-dried deboronated zeolitic material of framework type MWW (deboronated MWW) had a B content of 0.08 wt.%, a Si content of 42 wt.%, and a TOC content of 0.23 wt.%.

[0186] A titanium zeolite having the MWW framework type (TiMWW) in powder form was prepared according to the following recipe:

[0187] Initial mass: Piperidine 303.1g Tetrabutyl orthotitanate 43.13g Deboronated MWW 200g 821.8g deionized water.

[0188] Piperidine was added to a beaker containing 500 g of deionized water and stirred at 200 rpm for 10 minutes. Tetrabutyl orthotitanate (probe #6 from Example 1) with an APHA color number of 537 was added with stirring. After 15 minutes of stirring, 321.8 g of demineralized water was added, followed by stirring for an additional 15 minutes. The deboronated MWW was added, and the suspension was stirred for 60 minutes. The suspension was then transferred to a 2.5-liter autoclave and heated at 170°C with stirring for 48 hours. After cooling, the suspension was filtered through a porcelain filter, washed with deionized water, and the filter cake was dried at 120°C for 10 hours. 90 g of the dried material was added to a four-neck round-bottom flask containing 1800 g of 10% HNO3 solution with stirring (200 rpm). The suspension was heated to 100°C under reflux for 1 hour, cooled, filtered through a porcelain filter, and washed three times with 1000 ml of deionized water. The filter cake was dried at 120°C for 4 hours and the powder was calcined at 550°C for 5 hours (heating rate 2°C / min).

[0189] After calcination, a zeolitic material (TiMWW) was obtained in powder form. The crystallinity was 74% as determined by Reference Example 7. The particles exhibited a Ti content of 1.9% by weight and a Si content of 42% by weight, calculated as elemental Ti, based on the total mass of the particles obtained.

[0190] The absorbance of the powder in diffusely reflected light was determined as in Example 2, and the results obtained from the Kubelka-Munk transformation (KM) are shown in Figure 3. The slope above 330 nm (from about 330 nm to about 350 nm) (shown in the magnified portion on the right side of Figure 3) indicated the presence of some anatase.

[0191] Example 7: Epoxidation of propene Example 7.1: Preliminary Test - PO Test a) TS-1 with methanol as the solvent The TS-1 powders from Examples 2, 3, 4 and Comparative Examples 1 and 2 were preliminarily tested for their suitability as general epoxidation catalysts using methanol (45 ml) as the solvent by the PO test described in Reference Example 1. The respective resulting values ​​of propylene oxide activity and a summary of the powder properties are shown in Table 5 below.

[0192] [Table 5]

[0193] The above results indicate that catalysts prepared from tetraethyl orthotitanate with an APHA color number higher than 300 have poor epoxidation performance. Clearly, TS-1 powder prepared from tetraethyl orthotitanate with an APHA color number lower than 300 exhibits very good propylene oxide activity according to the PO test, making it a promising catalyst candidate for industrial continuous epoxidation reactions.

[0194] b) TiMWW in acetonitrile The TiMWW powders of Example 6 and Comparative Example 3 were preliminarily tested for their suitability as general epoxidation catalysts using acetonitrile (45 ml) as the solvent by the PO test described in Reference Example 1. The respective resulting values ​​for propylene oxide activity and a summary of the powder properties are shown in Table 6 below.

[0195] [Table 6]

[0196] The above results show that TiMWW catalysts prepared from tetrabutyl orthotitanate with APHA color numbers above 300 already showed good propylene oxide activity according to the PO test. However, the results of the PO test were found to be further improved when Ti-containing compounds with APHA color numbers below 300 were used, indicating that TiMWW powders prepared from tetrabutyl orthotitanate with APHA color numbers below 300 are promising candidates for catalysts in industrial continuous epoxidation reactions.

[0197] Example 7.2: Catalytic properties of molded articles in continuous epoxidation reactions The properties of the molded articles of Examples 2, 3, and 4 and Comparative Examples 1 and 2 (TS-1 catalyst) were investigated in a continuous epoxidation reaction as described in Reference Example 2. The hydrogen peroxide conversion, determined based on the reaction mixture leaving the reactor, was kept essentially constant at 90% as described in Reference Example 2. The selectivity of a given propylene oxide to hydrogen peroxide was determined over time on stream (TOS) (S(HO) vs. PO). The epoxidation was carried out for 550 hours.

[0198] The resulting selectivities to propylene oxide (PO) (S(HO) vs. PO, calculated according to Reference Example 1 based on data measured at the end of the epoxidation (500 hours), the temperature of the cooling medium, and the average temperature of the epoxidation zone) are shown in Table 7. Table 7 below shows the APHA color numbers of each Ti-containing compound used to prepare each TS-1 powder and subsequently each molded part.

[0199] [Table 7]

[0200] The results of the continuous epoxidation reactions are shown in Figures 4-6. Here, the selectivity of propylene oxide (S(H2O2) vs. PO) to hydrogen peroxide (H2O2) was determined according to Reference Example 2 (see Figures 5 and 6). The experiments showed that the performance of the TS-1 catalyst decreased as the APHA number of the Ti-containing compound used to synthesize the catalyst powders according to Examples 2-4 and Comparative Examples 1-2 increased. Even though the results for the different TS-1 catalysts appeared comparable during the initial run time, a significant gap opened up at longer run times (e.g., >150 h, preferably >200 h, more preferably >250 h). When the APHA number exceeded 300, much higher temperatures in the epoxidation zone (and therefore higher cooling medium temperatures) were required to maintain hydrogen peroxide conversion above 90% (see Figures 4 and 6). However, at these higher APHA numbers for the Ti-containing compound, selectivity was less than 84% at 500 h. The TS-1 catalyst based on a Ti-containing compound with an APHA color number of 300 still achieved a selectivity of about 85% at 500 h. The TS-1 catalyst based on a Ti-containing compound with an APHA color number of less than 300 showed significantly better selectivity, with selectivity clearly exceeding about 92% at 500 h.

[0201] BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows the XRD spectrum of the solid obtained in Comparative Example 2, zooming in on the area where the anatase-related peaks are present. 98.5% of the resulting particles were TS-1 structure, with 1.5% anatase. The impulse is shown on the y-axis. The 2-theta value is shown on the x-axis.

[0202] Figure 2 shows the Kubelka-Munk diagram calculated based on the %R spectra, measured on a Lambda 950 UV / VIS / NIR spectrophotometer equipped with a 150 mm integrating sphere (Ulbrichtkugel) showing the lamp switching points, for the titanium silicalite-1 (TS-1) powders of Examples 2-4 and Comparative Examples 1 and 2. The Kubelka-Munk transformation (KM) is shown on the y-axis versus wavelength in nanometers on the x-axis. The band above 330 nm (ranging from about 330 nm to about 350 nm) indicates the presence of significant amounts of anatase in samples made from tetraethyl orthotitanate with APHA numbers >300.

[0203] FIG. 3 shows the Kubelka-Munk diagram calculated based on the %R spectra, measured on a Lambda 950 UV / VIS / NIR spectrophotometer equipped with a 150 mm integrating sphere (Ulbrichtkugel) showing the lamp switching points, for the TiMWW powders of Example 6 and Comparative Example 3. The Kubelka-Munk transformation (KM) is shown on the y-axis versus wavelength in nanometers on the x-axis. The insert on the right shows a magnified view of the image portion between 0 and 3 on the y-axis. The slope above 330 nm for Comparative Example 3 (in the range from about 330 nm to about 350 nm) indicates the presence of some anatase in samples made from tetrabutyl orthotitanate with APHA numbers >300.

[0204] FIG. 4 shows the results of the continuous epoxidation reaction of Example 7.2, with the cooling medium temperature in °C on the y-axis and the runtime in h on the x-axis.

[0205] Figure 5 shows the results of the continuous epoxidation reaction of Example 7.2, where the selectivity of propylene oxide over hydrogen peroxide (S(H2O2) vs. PO) was determined according to Reference Example 2 and is shown in % on the y-axis. Run times are shown in hours on the x-axis.

[0206] FIG. 6 shows a summary of the results of the continuous epoxidation reaction of Example 7.2, with selectivity and temperature shown on the y-axis in % and ° C., respectively, and run time shown on the x-axis in hours.

[0207] References - US2013 / 296159A1 - EP0712852A1 - Deng-Gao Huang,Xian Zhang,Bao-Hui Chen,Zi-Sheng Chao Catalysis Today 158 (2010)510-514-IN189381A - handbook「Betriebsanleitung der Material-Pruefmaschine」、version1.1,Zwick Technische Dokumentationによる、August-Nagel-Strasse11,D-89079Ulm、ドイツ(1999年) - handbook「Register1:Betriebsanleitung / Sicherheitshandbuch fuer die Material-Pruefmaschine Z2.5 / TS1S」、version1.5、2001年12月、Zwick GmbH&Co.による、Technische Dokumentation,August-Nagel-Strasse11,D-89079Ulm、ドイツ - US2007 / 0099299A1 - Stallmach et al.、Annual Reports、NMR Spectroscopy2007年、第61巻、第51~131頁 - S.Kolitcheff,E. Jolimaitre,A. Hugon,J.Verstraete,M.Rivallan,P-L.Carrette,F.Couenne and M.Tayakout-Fayolle,Catal.Sci.Technol.,2018,8、第4537頁 - F.Elwinger,P.Pourmand,and I.Furo,J.Phys.Chem.C.2017,121、第(13757 - 13764)頁 - M.Holz,S.R.Heil and A.Sacco.Phys.Chem.Chem.Phys.,2000,2,4740-4742 - EP1122249A1 It should be noted that in the translation of item , since the original text format is a bit unclear about the specific range expression method, it is tentatively translated as a range in parentheses. If there are specific requirements or corrections, please adjust accordingly.- EP1122249A1 - WO2015 / 049327A1 - Ullmann's Encyclopedia of Industrial Chemistry, 5th edition, Volume A13 (1989), pp. 443-466

Claims

1. A zeolite material of MFI- or MWW-framework type having a framework structure containing Si, O, and Ti obtained from a Ti-containing compound, wherein the Ti-containing compound has an APHA color number of 300 or less, and the Ti-containing compound is a Ti(O-alkyl) ４ wherein each alkyl group is independently selected from branched or unbranched C1 to C6 alkyl.

2. The Ti-containing alcoholate is tetraethyl orthotitanate (Ti(OEt) ４ ), tetraisopropyl orthotitanate (Ti(OPr) ４ ), tetra-n-butyl orthotitanate Ti(OBu) ４ 10. A zeolite material of MFI- or MWW-framework type having a framework structure containing Si, O, and Ti, obtained from the Ti-containing compound according to claim 1, which is independently selected from the group consisting of:

3. 3. A zeolite material of MFI- or MWW-framework type having a framework structure containing Si, O, and Ti, obtained from the Ti-containing compound according to claim 1 or 2, wherein the Ti-containing compound comprises at least 90 mass % of the Ti-containing alcoholate, based on the total mass of the Ti-containing compound.

4. The Ti-containing compound is a compound represented by the general formula (I) in an amount of 10 mass % or less based on the total mass of the Ti-containing compound. 【Chemical 1】 (In the formula, R, R １ and R ２ are independently selected from the group consisting of a hydrogen atom and a branched or unbranched C1-C6 alkyl, and R ３ is selected from the group consisting of a hydrogen atom, a branched or unbranched C1-C6 alkyl, and a branched or unbranched C1-C6 alkenyl), a zeolite material of MFI- or MWW-framework type having a framework structure containing Si, O, and Ti, obtained from the Ti-containing compound according to any one of claims 1 to 3.

5. A method for producing a zeolite material having a framework structure containing Si, O, and Ti, comprising the steps of: a) preparing a mixture comprising one or more Si sources, one or more Ti-containing compounds as defined in claim 1, and one or more structure directing agents, and water; or a') preparing a mixture comprising one or more Si sources, a reaction product from premixing one or more Ti-containing compounds as defined in claim 1 with one or more structure directing agents, and water; and b) feeding the mixture prepared in step (a) or (a') into a reactor; and c) crystallizing a zeolitic material having a framework structure comprising Si, O, and Ti from the mixture in a reactor, the mixture being heated to a temperature in the range of 70 to 300°C; and 5. A method for producing a zeolite material having a framework structure containing Si, O, and Ti, wherein the Ti-containing compound has an APHA color number of 300 or less, and the Ti-containing compound is defined in any one of claims 1 to 4.

6. 5. A skeletal structure comprising Si, O, and Ti according to claim 1 , A molded article comprising a zeolitic material of MFI- or MWW framework type.

7. 7. Use of the molded article according to claim 6 as an adsorbent, absorbent, catalyst or catalyst component.

8. A method for epoxidizing an organic compound having at least one double bond, the method comprising contacting the organic compound having at least one double bond with a molded article described in claim 6 as an oxidation catalyst or as an oxidation catalyst component.

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