A MOLDING COMPRISING A TI-MWW ZEOLITE AND HAVING A SPECIFIC LEWIS ACIDITY

Abstract

The present invention relates to a molding comprising a zeolitic material having framework type MWW, wherein the framework structure comprises Ti, Si, and O, wherein the zeolitic material further comprises Zn and an alkaline earth metal M, the molding further comprising a binder, wherein the molding exhibits a specific Lewis acidity. Further, the present invention relates to the method of preparation of said molding and the use thereof.

Claims

1.-15. (canceled)

16. A molding comprising a zeolitic material having framework type MWW, having a framework structure comprising Ti, Si, and O, wherein the zeolitic material further comprises Zn and an alkaline earth metal M, the molding further comprising a binder, wherein the molding exhibits a integral extinction units of the IR band at 1490 cm.sup.−1 of equal to or smaller than 8, determined as described in Reference Example 1.

17. The molding of claim 16, comprising Si, calculated as element, in an amount in the range of from 20 to 60 weight-%, based on the total weight of the molding.

18. The molding of claim 16, comprising Ti, calculated as element, in an amount in the range of from 0.1 to 5 weight-%,

19. The molding of claim 16, comprising Zn, calculated as element, in an amount in the range of from 0.1 to 5 weight-%, based on the total weight of the molding.

20. The molding of claim 16, comprising the alkaline earth metal M, calculated as element, in an amount in the range of from 0.1 to 5 weight-%, based on the total weight of the molding.

21. The molding of claim 16, wherein the zeolitic material further comprises a rare earth metal.

22. The molding of claim 16, wherein the binder comprises Si and O.

23. The molding of claim 16, wherein the molding exhibits a total pore volume in the range of from 0.5 to 3.0 mL/g, wherein the pore volume is determined according to DIN 66133.

24. The molding of claim 16, wherein the molding comprises a concentration of acid sites in the range of from 0.05 to 1.00 mmol/g at a temperature lower than 200° C., and/or wherein the molding comprises a concentration of acid sites in the range of from 0.001 to 0.5 mmol/g at a temperature higher than 500° C., wherein the concentration of acid sites is determined by temperature programmed desorption of ammonia (NH.sub.3-TPD) according to Reference Example 5.

25. A process for preparing a molding comprising a zeolitic material having framework type MWW and a binder material, the process comprising i) providing a molding comprising a zeolitic material having framework type MWW, having a framework structure comprising Ti, Si, and O, wherein the zeolitic material further comprises Zn, an alkaline earth metal M, and optionally a rare earth metal, wherein the molding further comprises a binder for said zeolitic material; ii) preparing a mixture comprising the precursor molding according to (i) and water, and subjecting the mixture to a water treatment under hydrothermal conditions, obtaining a water-treated molding, and calcining the water-treated molding in a gas atmosphere.

26. The process of claim 25, wherein (i) comprises (i.1) providing a zeolitic material having framework type MWW and having a framework structure comprising Ti, Si, and O; (i.2) providing an aqueous solution of a source of Zn; (i.3) providing an aqueous solution of a source of an alkaline earth metal M; (i.4) optionally providing an aqueous solution of a source of a rare earth metal; (i.5) impregnating the zeolitic material provided according to (i.1) with the aqueous solution provided according to (i.2), the aqueous solution according to (i.3), and optionally the aqueous solution provided according to (i.4), obtaining an impregnated zeolitic material; (i.6) preparing a mixture comprising the impregnated zeolitic material obtained from (i.5) and a binder precursor; (i.7) shaping of the mixture obtained from (i.6).

27. A molding comprising a zeolitic material having framework type MWW and a binder material, obtainable or obtained by a process according to claim 25.

28. An adsorbent, an absorbent, a catalyst, or a catalyst compound comprising the molding according to claim 16.

29. A process for oxidizing an organic compound comprising bringing the organic compound in contact with a catalyst comprising a molding according to claim 16.

30. A process for preparing propylene oxide comprising reacting propene with hydrogen peroxide in acetonitrile solution in the presence of a catalyst comprising a molding according to claim 16 to obtain propylene oxide.

Description

[0300] The present invention is further illustrated by the following examples and reference examples.

REFERENCE EXAMPLE 1: DETERMINATION OF BRøNSTEDT AND LEWIS ACIDITY

[0301] In the examples, the Brønsted and Lewis acidities were determined using pyridine as the probe gas. The measurements were conducted using an IR-spectrometer Nicolet 6700 employing a FTIR-cell. The samples were pressed to a pellet for placing in the FTIR-cell for measurement. After being placed in the FTIR-cell, the samples were then heated in air to 350° C. and held at that temperature for 1 h for removing water and any volatile substances from the sample. The apparatus was then placed under high-vacuum (10-5 mbar), and the cell let cool to 80° C., at which it was held for the entire duration of the measurement for avoiding the condensation of pyridine in the cell.

[0302] Pyridine was then dosed into the cell in successive steps (0.01, 0.1, 1, and 3 mbar) to ensure the controlled and complete exposition of the sample.

[0303] The irradiation spectrum of the activated sample at 80° C. and 10-5 mbar was used as the background for the absorption spectra for compensating the influence of matrix bands.

[0304] For the analysis, the spectrum at a pressure of 1 mbar was used, since the sample was in a stable equilibrium. For the quantification, the extinction spectrum was used, since this allowed for the cancellation of the matrix effects.

[0305] The integral extinction units were determined as follows: the characteristic signals for the pyridine absorption were integrated and the thus determined area was scaled with the thickness of the pellet. For allowing a better comparison, the determined values were multiplied with a constant factor, said factor being 1000. Accordingly, the integral extinction units were calculated based on the measured spectrum according to formula I:

Integral extinction units=(Area below an extinction band at 1 mbar/value of thickness of disassembled pellet in μm)×1000.

[0306] The integral extinction units (integrale Extinktionseinheiten) of the IR bands at a pressure of 1 mbar are used herein as a value to define the Lewis acidity of a respective material. Further, the integral extinction units of the IR band at 1490 cm.sup.−1 at a pressure of 1 mbar are used herein as a further value to define the acidity of a respective material.

TABLE-US-00001 TABLE 1 Assignment of the IR-bands of pyridine acid sites pyridine species bands (cm.sup.−1) L Py 1440-1455 1575 1620 B PyH.sup.+ 1540-1550 1635-1640 B + L Py + PyH.sup.+ 1490 physical adsorbate adsorbated Py 1440 (overlay L) 1580-1595 Py = pyridine; PyH.sup.+ = pyridinium ion; B = Brønsted center; L = Lewis center

[0307] In the examples, the determination of the Lewis acid sites were determined considering the band at 1450 cm.sup.−1 and of the Brønsted acid sites considering the band at 1545 cm.sup.−1.

REFERENCE EXAMPLE 2: DETERMINATION OF THE TOTAL PORE VOLUME

[0308] The total pore volume was determined via intrusion mercury porosimetry according to DIN 66133.

REFERENCE EXAMPLE 3: DETERMINATION OF THE BET SPECIFIC SURFACE AREA

[0309] The BET specific surface area was determined via nitrogen physisorption at 77 K according to the method disclosed in DIN 66131. The N.sub.2 sorption isotherms at the temperature of liquid nitrogen were measured using Micrometrics ASAP 2020M and Tristar system for determining the BET specific surface area.

REFERENCE EXAMPLE 4: X-RAY POWDER DIFFRACTION AND DETERMINATION OF THE CRYSTALLINITY

[0310] Powder X-ray diffraction (PXRD) data was collected using a diffractometer (D8 Advance Series II, Bruker AXS GmbH) equipped with a LYNXEYE detector operated with a Copper anode X-ray tube running at 40 kV and 40 mA. The geometry was Bragg-Brentano, and air scattering was reduced using an air scatter shield.

[0311] Computing crystallinity: The crystallinity of the samples was determined using the software DIFFRAC.EVA provided by Bruker AXS GmbH, Karlsruhe. The method is described on page 121 of the user manual. The default parameters for the calculation were used.

[0312] Computing phase composition: The phase composition was computed against the raw data using the modelling software DIFFRAC.TOPAS provided by Bruker AXS GmbH, Karlsruhe. The crystal structures of the identified phases, instrumental parameters as well the crystallite size of the individual phases were used to simulate the diffraction pattern. This was fit against the data in addition to a function modelling the background intensities.

[0313] Data collection: The 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. The flat surface was achieved using a glass plate to compress and flatten the sample powder. The data was collected from the angular range 2 to 70 ° 2Theta with a step size of 0.02° 2Theta, while the variable divergence slit was set to an angle of 0.1°. The crystalline content describes the intensity of the crystalline signal to the total scattered intensity. (User Manual for DIFFRAC.EVA, Bruker AXS GmbH, Karlsruhe.)

REFERENCE EXAMPLE 5: DETERMINATION OF THE ACID SITES: TEMPERATURE PROGRAMMED DESORPTION OF AMMONIA (NH.SUB.3.-TPD)

[0314] The temperature-programmed desorption of ammonia (NH.sub.3-TPD) was conducted in an automated chemisorption analysis unit (Micromeritics AutoChem II 2920) having a thermal conductivity detector. Continuous analysis of the desorbed species was accomplished using an online mass spectrometer (OmniStar QMG200 from Pfeiffer Vacuum). The sample (0.1 g) was introduced into a quartz tube and analysed using the program described below. The temperature was measured by means of a Ni/Cr/Ni thermocouple immediately above the sample in the quartz tube. For the analyses, He of purity 5.0 was used. Before any measurement, a blank sample was analysed for calibration. [0315] 1. Preparation: Commencement of recording; one measurement per second. Wait for 10 minutes at 25° C. and a He flow rate of 30 cm.sup.3/min (room temperature (about 25° C.) and 1 atm); heat up to 600° C. at a heating rate of 20 K/min; hold for 10 minutes. Cool down under a He flow (30 cm.sup.3/min) to 100° C. at a cooling rate of 20 K/min (furnace ramp temperature); Cool down under a He flow (30 cm.sup.3/min) to 100° C. at a cooling rate of 3 K/min (sample ramp temperature). [0316] 2. Saturation with NH.sub.3: Commencement of recording; one measurement per second. Change the gas flow to a mixture of 10% NH.sub.3 in He (75 cm.sup.3/min; 100° C. and 1 atm) at 100° C.; hold for 30 min. [0317] 3. Removal of the excess: Commencement of recording; one measurement per second. Change the gas flow to a He flow of 75 cm.sup.3/min (100° C. and 1 atm) at 100° C.; hold for 60 min. [0318] 4. NH.sub.3-TPD: Commencement of recording; one measurement per second. Heat up under a He flow (flow rate: 30 cm.sup.3/min) to 600° C. at a heating rate of 10 K/min; hold for 30 min. [0319] 5. End of measurement.

[0320] Desorbed ammonia was measured by means of the online mass spectrometer, which demonstrated that the signal from the thermal conductivity detector was caused by desorbed ammonia. This involved utilizing the m/z=16 signal from ammonia in order to monitor the desorption of the ammonia. The amount of ammonia adsorbed (mmol/g of sample) was ascertained by means of the Micromeritics software through integration of the TPD signal with a horizontal baseline.

REFERENCE EXAMPLE 6: DETERMINATION OF THE HARDNESS

[0321] The crush strength as referred to in the context of the present invention is to be understood as having been determined via a crush strength test machine Z2.5/TS1S, supplier Zwick GmbH & Co., D-89079 Ulm, Germany. As to fundamentals of this machine and its operation, reference is made to the respective instructions handbook “Register 1: Betriebsanleitung/Sicherheitshandbuch für die Material-Prüfmaschine Z2.5/TS1S”, version 1.5, December 2001 by Zwick GmbH & Co. Technische Dokumentation, August-Nagel-Strasse 11, D-89079 Ulm, Germany. The machine was equipped with a fixed horizontal table on which the strand was positioned. A plunger having a diameter of 3 mm which was freely movable in vertical direction actuated the strand against the fixed table. The apparatus was operated with a preliminary force of 0.5 N, a shear rate under preliminary force of 10 mm/min and a subsequent testing rate of 1.6 mm/min. The vertically movable plunger was connected to a load cell for force pick-up and, during the measurement, moved toward the fixed turntable on which the molding (strand) to be investigated is positioned, thus actuating the strand against the table. The plunger was applied to the strands perpendicularly to their longitudinal axis. With said machine, a given strand as described below was subjected to an increasing force via a plunger until the strand was crushed. The force at which the strand crushes is referred to as the crushing strength of the strand. Controlling the experiment was carried out by means of a computer which registered and evaluated the results of the measurements. The values obtained are the mean value of the measurements for 10 strands in each case.

REFERENCE EXAMPLE 7: DETERMINATION OF THE WATER UPTAKE

[0322] The water adsorption/desorption isotherms measurements were performed on a VTI SA instrument from TA Instruments following a step-isotherm program. The experiment consisted of a run or a series of runs performed on a sample material that has been placed on the microbalance pan inside of the instrument. Before the measurement was started, the residual moisture of the sample was removed by heating the sample to 100° C. (heating ramp of 5° C./min) and holding it for 6 h under a N.sub.2 flow. After the drying program, the temperature in the cell was decreased to 25° C. and kept isothermal during the measurements. The microbalance was calibrated, and the weight of the dried sample was balanced (maximum mass deviation 0.01 weight-%). Water uptake by the sample was measured as the increase in weight over that of the dry sample. First, an adsorption curve was measured by increasing the relative humidity (RH) (expressed as weight-% water in the atmosphere inside of the cell) to which the samples was exposed and measuring the water uptake by the sample at equilibrium. The RH was increased with a step of 10% from 5% to 85% and at each step the system controlled the RH and monitored the sample weight until reaching the equilibrium conditions and recording the weight uptake. The total adsorbed water amount by the sample was taken after the sample was exposed to the 85% RH. During the desorption measurement the RH was decreased from 85% to 5% with a step of 10% and the change in the weight of the sample (water uptake) was monitored and recorded.

REFERENCE EXAMPLE 8: DETERMINATION OF THE PROPYLENE OXIDE ACTIVITY AND THE PRESSURE DROP RATE (PO TEST)

[0323] The PO test as disclosed in the following represents a preliminary test procedure to assess the possible suitability of the moldings as catalyst for the epoxidation of propene. In the PO test, a molding is tested as catalyst in a mini autoclave with respect to the reaction of propene with hydrogen peroxide, provided as an aqueous hydrogen peroxide solution (30 weight-%) to yield propylene oxide. In particular, 0.63 g of a molding is introduced together with 79.2 g of acetonitrile and 12.4 g of propene at room temperature, and 22.1 g of the aqueous hydrogen peroxide in a steel autoclave. After a reaction time of 4 hours at 40° C., the mixture was cooled and depressurized, and the liquid phase was analyzed by gas chromatography with respect to its propylene oxide content. The propylene oxide content of the liquid phase (in weight-%) is the result of the PO test.

REFERENCE EXAMPLE 9: DETERMINATION OF THE PROPYLENE OXIDE ACTIVITY IN A CONTINUOUS EPOXIDATION REACTION

[0324] Continuous epoxidation reaction was carried out as described in WO 2015/010990 A, in Reference Example 1, page 55, line 14 to page 57, line 10. The reaction temperature was set to a value of 45° C. (see WO 2015/010990 A, page 56, lines 16 to 18). The temperature was adjusted to achieve an essentially constant hydrogen peroxide conversion of 90% (see WO 2015/010990 A, page 56, lines 21 to 23). KH.sub.2PO.sub.4 was employed as additive (see WO 2015/010990 A, page 56, lines 7 to 10), the concentration of the additive was 130 micromol per mol hydrogen peroxide. As catalysts, the catalysts according to Comparative Example 22, Reference Example 20 and Example 23 hereinbelow were employed (see WO 2015/010990 A, page 55, lines 16 to 18).

REFERENCE EXAMPLE 10: DETERMINATION OF THE C VALUE (BET C CONSTANT)

[0325] The C value was determined by usual calculation ((slope/intercept)+1) based on the plot of the BET value 1/(V((p/p.sub.0)−1)) against p/p.sub.0, as known by the skilled person. p is the partial vapour pressure of adsorbate gas in equilibrium with the surface at 77.4 K (b.p. of liquid nitrogen), in Pa, p.sub.0 is the saturated pressure of adsorbate gas, in Pa, and V is the volume of gas adsorbed at standard temperature and pressure (STP) [273.15 K and atmospheric pressure (1.013×10.sup.5 Pa)], in mL.

REFERENCE EXAMPLE 11: IR MEASUREMENTS

[0326] The IR measurements were performed on a Nicolet 6700 spectrometer. The zeolitic materials were pressed into a self-supporting pellet without the use of any additives. The pellet was introduced into a high vacuum cell placed into the IR instrument. Prior to the measurement the sample was pretreated in high vacuum (10.sup.−5 mbar) for 3 h at 300° C. The spectra were collected after cooling the cell to 50° C. The spectra were recorded in the range of 4000 cm.sup.−1 to 800 cm.sup.−1 at a resolution of 2 cm.sup.−1. The obtained spectra were represented by a plot having on the x axis the wavenumber (cm.sup.−1) and on the y axis the absorbance (arbitrary units). For the quantitative determination of the peak heights and the ratio of the peak heights, a baseline correction was carried out.

REFERENCE EXAMPLE 12: DETERMINATION OF THE TORTUOSITY PARAMETER RELATIVE TO WATER

[0327] Samples were prepared for NMR analyses by drying a small quantity (0.05-0.2 g) of catalyst at T>350° C. under vacuum overnight in NMR measurement tubes. The sample was then filled via a vacuum line with nanopure water (Millipore Advantage A10) to 90% of the pore volume of the catalyst support (determined by Hg-porosimetry). The filled sample was then flame sealed into the measurement tube and left overnight before measurement.

[0328] The NMR analyses to determine the self diffusion coefficient (D.sub.eff) for water in the catalyst materials were conducted at 20° C. and 1 bar at 400 MHz 1H resonance frequency with Bruker Avance III NMR spectrometer. A Bruker Diff50 probe head was used with Bruker Great 60A gradient amplifiers. A temperature of 20° C. was maintained with water cooled gradient coils. The pulse program used for the PFG NMR self-diffusion analyses was the stimulated spin echo with pulsed field gradients according to FIG. 1b of US 20070099299 A1. For each sample, the spin echo attenuation curves were measured at different diffusion times (between 20 and 100 ms) by stepwise increase in the intensity of the field gradients (to a maximum gmax=3 T/m). The gradient pulse length was 1 ms. Spin echo attenuation curves were fitted to equation 6 of US 2007/0099299 A, by way of an example, a double logarithmic plot of data from a catalyst support at the various diffusion times used is shown in figure X. The slope of each line corresponds to a diffusion coefficient. The average diffusion coefficient, across all diffusion times, was used to calculate tortuosity for each catalyst support, according to Formula II (see Reference Example 2).

[0329] PFG NMR enables the destruction free examination of thermal molecular motion, in free gases and liquids, in macro and supra molecular solutions and of adsorbed molecules in porous systems. The principle and applications are as described in US 20070099299 A1. From the diffusion coefficient obtained by NMR according to Reference Example 4, the tortuosity factor was calculated. The tortuosity factor of a porous material is determined from the self diffusion coefficient of a probe molecule in the porous system (D.sub.eff) and the self diffusion coefficient of the free liquid (D.sub.0) according to formula II (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):

[00001]$\begin{array}{cc}\tau =\frac{D_0}{D_{eff}}.& \left(\mathrm{ll}\right)\end{array}$

[0330] The free diffusion coefficient for water was taken as 2.02×10.sup.−9 m.sup.2 s.sup.−1 at 20° C. (see M. Holz, S. R. Heil and A. Sacco. Phys. Chem. Chem. Phys., 2000, 2, 4740-4742).

REFERENCE EXAMPLE 12: PREPARATION OF A TI-MWW

[0331] A zeolitic material having framework structure MWW and comprising Ti (also abbreviated herein as Ti-MWW) was provided similar to a zeolitic material prepared according to Example 5, 5.1 to 5.3, of WO 2013/117536 A, page 83, line 26 to page 92, line 7. The resulting zeolitic material had a crystallinity of 89%, a BET specific surface area of 353 m.sup.2/g, a C value of −94, a Ti content of 1.5 g Ti/100 g. Further, the resulting zeolitic material displayed a water adsorption of 12 weight-%.

REFERENCE EXAMPLE 14: PREPARATION OF A TI-MWW IMPREGNATED WITH ZN

[0332] A zeolitic material having framework structure MWW, comprising Ti, and being impregnated with Zn was provided according to Reference Example 1 of WO 2013/117536 A2 on pages 57-66.

REFERENCE EXAMPLE 15: PREPARATION OF A TI-MWW IMPREGNATED WITH BA

[0333] 1.2 g barium nitrate (Ba(NO.sub.3).sub.2) were solved in 60 g deionized water in a beaker under stirring for 1 h. Then, 40.0 g of Ti-MWW according to Reference Example 12 were added to the mixture and kept for 40 h at room temperature. The resulting solids were dried in air for 5 h at 110° C. and subsequently calcined in air for 8 h at 550° C. to obtain the product. The yield was 39.6 g.

[0334] The resulting material had a Ba content of 1.6 g/100 g, a Si content of 43 g/100 g, and a Ti content of 1.5 g/100 g.

REFERENCE EXAMPLE 16: PREPARATION OF A TI-MWW IMPREGNATED WITH BA AND ZN

[0335] 1.20 g barium nitrate (Ba(NO.sub.3).sub.2) and 1.64 zink nitrate (Zn(NO.sub.3).sub.2.6H.sub.2O) were solved in 60.00 g deionized water in a beaker under stirring for 1 h. Then, 40.00 g of Ti-MWW according to Reference Example 12 were added to the mixture and kept for 36 h at room temperature. The resulting solids were dried in air for 5 h at 110° C. and subsequently calcined in air for 8 h at 550° C. to obtain the product. The yield was 40.3 g.

[0336] The resulting material had a Ba content of 1.6 g/100 g, a Si content of 42 g/100 g, a Ti content of 1.5 g/100 g and a Zn content of 0.88 g/100 g.

REFERENCE EXAMPLE 17: PREPARATION OF A TI-MWW IMPREGNATED WITH BA, ZN, AND LA

[0337] 1.20 g barium nitrate (Ba(NO.sub.3).sub.2), 1.64 zink nitrate (Zn(NO.sub.3).sub.2.6H.sub.2O) and 1.24 g lanthanum nitrate (La(NO.sub.3).sub.3.6H.sub.2O) were solved in 60.00 g deionized water in a beaker under stirring for 1 h. Then, 40.00 g of Ti-MWW according to Reference Example 12 were added to the mixture and kept for 36 h at room temperature. The resulting solids were dried in air for 5 h at 110° C. and subsequently calcined in air for 8 h at 550° C. to obtain the product. The yield was 40.9 g.

[0338] The resulting material had a Ba content of 1.6 g/100 g, a La content of 1.0 g/100 g, a Si content of 42 g/100 g, a Ti content of 1.5 g/100 g and a Zn content of 0.88 g/100 g.

REFERENCE EXAMPLE 18: SHAPING OF A TI-MWW IMPREGNATED WITH ZN

[0339] 30 g Ti-MWW impregnated with Zn according to Reference Example 14 and 1.92 g methyl cellulose (Walocel MW 15000 GB, Wolff Cellulosics GmbH & Co. KG, Germany) were provided in a kneader and kneaded for 5 minutes. Then, 60 mL of deionized water together with 18.75 g colloidal silica (Ludox® AS 40) were added and the mixture was further kneaded for 10 minutes. Then, 10 mL of deionized water were added and the mixture was further kneaded for 15 minutes. The total kneading time was 45 minutes.

[0340] The kneaded mass was extruded at a pressure of 120 bar(abs) to give strands having a circular cross-section with a diameter of 1.7 mm. Subsequently, the extruded strands were dried and calcined in air according to the following program:

[0341] 1. heating within 40 minutes up to a temperature of 120° C.;

[0342] 2. keeping the temperature of 120° C. for 6 h;

[0343] 3. heating within 380 minutes to a temperature of 500° C.;

[0344] 4. keeping the temperature of 500° C. for 5 h.

[0345] The resulting material had a TOC of less than 0.1 g/100 g, a Zn content of 1.1 g/100 g, a Si content of 43 g/100 g, and a Ti content of 1.9 g/100 g. The Lewis acidity was determined according to Reference Example 1, whereby the integral extinction units of the IR bands of the Lewis acid sites were determined as being 14.2, and whereby the integral extinction units of the IR band at 1490 cm.sup.−1 were determined as being 0. Further, the integral extinction units of the Brønstedt acid sites were observed as being 0.23, determined according to Reference Example 1. In addition, the Lewis acid site density was determined by temperature-programmed-desorption of ammonia according to Reference Example 5. Thus, the Lewis acid site density was determined via NH.sub.3-TPD as being 0.26 mmol/g at a temperature below 200° C., no Lewis acid sites were observed in the temperature region between 200 to 400° C., and the Lewis acid site density of 0.01 mmol/g was observed at a temperature above 500° C.

REFERENCE EXAMPLE 19: SHAPING OF A TI-MWW IMPREGNATED WITH BA

[0346] 30 g Ti-MWW impregnated with Ba according to Reference Example 15 and 1.92 g methyl cellulose (Walocel MW 15000 GB, Wolff Cellulosics GmbH & Co. KG, Germany) were provided in a kneader and kneaded for 5 minutes. Then, 60 mL of deionized water together with 18.75 g colloidal silica (Ludox® AS 40) were added and the mixture was further kneaded for 10 minutes. Then, 10 mL of deionized water were added and the mixture was further kneaded for 15 minutes. The total kneading time was 45 minutes.

[0347] The kneaded mass was extruded at a pressure of 120 bar(abs) to give strands having a circular cross-section with a diameter of 1.7 mm. Subsequently, the extruded strands were dried and calcined in air according to the following program:

[0348] 1. heating within 40 minutes up to a temperature of 120° C.;

[0349] 2. keeping the temperature of 120° C. for 6 h;

[0350] 3. heating within 380 minutes to a temperature of 500° C.;

[0351] 4. keeping the temperature of 500° C. for 5 h.

[0352] The resulting material had a TOC of less than 0.1 g/100 g, a Ba content of 1.3 g/100 g, a Si content of 43 g/100 g, and a Ti content of 1.2 g/100 g. The Lewis acidity was determined according to Reference Example 1, whereby the integral extinction units of the IR bands of the Lewis acid sites were determined as being 100.7, and whereby the integral extinction units of the IR band at 1490 cm.sup.−1 at a pressure of 1 mbar were determined as being 9.77. Further, no Brønstedt acid sites were observed, determined according to Reference Example 1. In addition, the Lewis acid site density was determined by temperature-programmed-desorption of ammonia according to Reference Example 5. Thus, the Lewis acid site density was determined via NH.sub.3-TPD as being 0.15 mmol/g at a temperature below 200° C., no Lewis acid sites were observed in the temperature region between 200 to 400° C., and the Lewis acid site density of 0.02 mmol/g was observed at a temperature above 500° C.

REFERENCE EXAMPLE 20: SHAPING OF A TI-MWW IMPREGNATED WITH BA AND ZN

[0353] 30 g Ti-MWW impregnated with Ba and Zn according to Reference Example 16 and 1.92 g methyl cellulose (Walocel MW 15000 GB, Wolff Cellulosics GmbH & Co. KG, Germany) were provided in a kneader and kneaded for 5 minutes. Then, 60 mL of deionized water together with 18.75 g colloidal silica (Ludox® AS 40) were added and the mixture was further kneaded for 10 minutes. Then, 10 mL of deionized water were added and the mixture was further kneaded for 15 minutes. The total kneading time was 45 minutes.

[0354] The kneaded mass was extruded at a pressure of 120 bar(abs) to give strands having a circular cross-section with a diameter of 1.7 mm. Subsequently, the extruded strands were dried and calcined in air according to the following program:

[0355] 1. heating within 40 minutes up to a temperature of 120° C.:

[0356] 2. keeping the temperature of 120° C. for 6 h;

[0357] 3. heating within 380 minutes to a temperature of 500° C.;

[0358] 4. keeping the temperature of 500° C. for 5 h.

[0359] The resulting material had a TOC of less than 0.1 g/100 g, a Ba content of 1.2 g/100 g, a Si content of 43 g/100 g, a Ti content of 1.2 g/100 g and a Zn content of 0.69 g/100 g. The Lewis acidity was determined according to Reference Example 1, whereby the integral extinction units of the IR bands of the Lewis acid sites were determined as being 108.9, and whereby the integral extinction units of the IR band at 1490 cm.sup.−1 at a pressure of 1 mbar were determined as being 11.05. Further, no Brønstedt acid sites were observed, determined according to Reference Example 1. In addition, the Lewis acid site density was determined by temperature-programmed-desorption of ammonia according to Reference Example 5. Thus, the Lewis acid site density was determined via NH.sub.3-TPD as being 0.23 mmol/g at a temperature below 200° C., no Lewis acid sites were observed in the temperature region between 200 to 400° C., and the Lewis acid site density of 0.02 mmol/g was observed at a temperature above 500° C.

REFERENCE EXAMPLE 21: SHAPING OF A TI-MWW IMPREGNATED WITH BA, ZN AND LA

[0360] 30 g Ti-MWW impregnated with Ba, Zn and La according to Reference Example 17 and 1.92 g methyl cellulose (Walocel MW 15000 GB, Wolff Cellulosics GmbH & Co. KG, Germany) were provided in a kneader and kneaded for 5 minutes. Then, 60 mL of deionized water together with 18.75 g colloidal silica (Ludox® AS 40) were added and the mixture was further kneaded for 10 minutes. Then, 10 mL of deionized water were added and the mixture was further kneaded for 15 minutes. The total kneading time was 45 minutes.

[0361] The kneaded mass was extruded at a pressure of 120 bar(abs) to give strands having a circular cross-section with a diameter of 1.7 mm. Subsequently, the extruded strands were dried and calcined in air according to the following program:

[0362] 1. heating within 40 minutes up to a temperature of 120° C.;

[0363] 2. keeping the temperature of 120° C. for 6 h;

[0364] 3. heating within 380 minutes to a temperature of 500° C.;

[0365] 4. keeping the temperature of 500° C. for 5 h.

[0366] The resulting material had a TOC of less than 0.1 g/100 g, a Ba content of 1.2 g/100 g, a La content of 0.78 g/100 g, a Si content of 42 g/100 g, a Ti content of 1.2 g/100 g and a Zn content of 0.68 g/100 g. The Lewis acidity was determined according to Reference Example 1, whereby the integral extinction units of the IR bands of the Lewis acid sites were determined as being 118.3, and whereby the integral extinction units of the IR band at 1490 cm.sup.−1 at a pressure of 1 mbar were determined as being 11.53. Further, no Brønstedt acid sites were observed, determined according to Reference Example 1. In addition, the Lewis acid site density was determined by temperature-programmed-desorption of ammonia according to Reference Example 5. Thus, the Lewis acid site density was determined via NH.sub.3-TPD as being 0.23 mmol/g at a temperature below 200° C., no Lewis acid sites were observed in the temperature region between 200 to 400° C., and the Lewis acid site density of 0.01 mmol/g was observed at a temperature above 500° C.

COMPARATIVE EXAMPLE 22: WATER TREATMENT OF A SHAPED TI-MWW IMPREGNATED WITH ZN

[0367] 7 g of the strands prepared according to Reference Example 18 were mixed with 140 g deionized water. The resulting mixture was heated to a temperature of 145° C. for 8 h in an autoclave. Thereafter, the obtained water-treated strands were separated and sieved over a 0.8 mm sieve. The obtained strands were then washed with deionized water and pre-dried in a stream of nitrogen at ambient temperature. The washed and pre-dried strands were subsequently dried and calcined in air according to the following program:

[0368] 1. heating within 60 minutes up to 120° C.;

[0369] 2. keeping the temperature of 120° C. for 4 h;

[0370] 3. heating within 165 minutes up to 450° C.;

[0371] 4. keeping the temperature of 450° C. for 2 h.

[0372] The resulting material showed a BET specific surface area of 283 m.sup.2/g, had a TOC of less 0.1 g/100 g, a Zn content of 1.9 g/100 g, a Si content of 42° g/100 g, and a Ti content of 1.9 g/100 g, each determined as described hereinabove. The resulting material displayed a water uptake of 10.2 weight-%, determined as described in Reference Example 7. The crushing strength of the strands determined as described hereinabove was 19 N, and the pore volume determined as described hereinabove was 1.0 mL/g. The tortuosity parameter relative to water was observed as being 1.6, determined according to Reference Example 12 The Lewis acidity was determined according to Reference Example 1, whereby the integral extinction units of the IR bands of the Lewis acid sites were determined as being 77.8, and whereby the integral extinction units of the IR band at 1490 cm.sup.1 at a pressure of 1 mbar were determined as being 8.1. Further, no Brønstedt acid sites were observed, determined according to Reference Example 1. In addition, the Lewis acid site density was determined by temperature-programmed-desorption of ammonia according to Reference Example 5. Thus, the Lewis acid site density was determined via NH.sub.3-TPD as being 0.24 mmol/g at a temperature below 200° C., no Lewis acid sites were observed in the temperature region between 200 to 400° C., and the Lewis acid site density of 0.05 mmol/g was observed at a temperature above 500° C.

EXAMPLE 23: WATER TREATMENT OF A SHAPED TI-MWW IMPREGNATED WITH BA AND ZN

[0373] 21 g of the strands prepared according to Example 20 were mixed in four portions of each 7 g with 140 g deionized water per portion. The resulting mixtures were heated to a temperature of 145° C. for 8 h in an autoclave. Thereafter, the obtained water-treated strands were separated and sieved over a 0.8 mm sieve. The obtained strands were then washed with deionized water and pre-dried in a stream of nitrogen at ambient temperature. The washed and pre-dried strands were subsequently dried and calcined in air according to the following program:

[0374] 1. heating within 60 minutes up to 120° C.;

[0375] 2. keeping the temperature of 120° C. for 4 h;

[0376] 3. heating within 165 minutes up to 450° C.;

[0377] 4. keeping the temperature of 450° C. for 2 h.

[0378] The resulting material showed a BET specific surface area of 284 m.sup.2/g, had a TOC of less 0.1 g/100 g, a Ba content of 1.2 g/100 g, a Si content of 43° g/100 g, a Ti content of 1.2 g/100 g, and a Zn content of 0.7 g/100 g, each determined as described hereinabove. The resulting material displayed a water uptake of 10.4 weight-%, determined as described in Reference Example 7.

[0379] The resulting material displayed a concentration of acid sites of 0.25 at a temperature lower than 200° C., of 0 at a temperature in the range of from 200 to 400° C., and of 0.05 at a temperature higher than 500° C., determined by temperature programmed desorption of ammonia (NH.sub.3-TPD) according to Reference Example 5. The crushing strength of the strands determined as described hereinabove was 9 N, and the pore volume determined as described hereinabove was 1.5 mL/g. The tortuosity parameter relative to water was observed as being 2.0, determined according to Reference Example 12. The Lewis acidity was determined according to Reference Example 1, whereby the integral extinction units of the IR bands of the Lewis acid sites were determined as being 78.5, and whereby the integral extinction units of the IR band at 1490 cm.sup.−1 at a pressure of 1 mbar were determined as being 6.8. Further, no Brønstedt acid sites were observed, determined according to Reference Example 1. In addition, the Lewis acid site density was determined by temperature-programmed-desorption of ammonia according to Reference Example 5. Thus, the Lewis acid site density was determined via NH.sub.3-TPD as being 0.25 mmol/g at a temperature below 200° C., no Lewis acid sites were observed in the temperature region between 200 to 400° C., and the Lewis acid site density of 0.05 mmol/g was observed at a temperature above 500° C.

EXAMPLE 24: WATER TREATMENT OF A SHAPED TI-MWW IMPREGNATED WITH BA, ZN AND LA

[0380] 21 g of the strands prepared according to Example 21 were mixed in four portions of each 7 g with 140 g deionized water per portion. The resulting mixtures were heated to a temperature of 145° C. for 8 h in an autoclave. Thereafter, the obtained water-treated strands were separated and sieved over a 0.8 mm sieve. The obtained strands were then washed with deionized water and pre-dried in a stream of nitrogen at ambient temperature. The washed and pre-dried strands were subsequently dried and calcined in air according to the following program:

[0381] 1. heating within 60 minutes up to 120° C.;

[0382] 2. keeping the temperature of 120° C. for 4 h;

[0383] 3. heating within 165 minutes up to 450° C.;

[0384] 4. keeping the temperature of 450° C. for 2 h.

[0385] The resulting material had a TOC of less 0.1 g/100 g, a Ba content of 1.2 g/100 g, a La content of 0.75 g/100 g, a Si content of 42° g/100 g, a Ti content of 1.1 g/100 g, and a Zn content of 0.68 g/100 g, each determined as described hereinabove. The resulting material showed a BET specific surface area of 334 m.sup.2/g. The pore volume determined as described hereinabove was 1.7 mL/g. The tortuosity parameter relative to water was observed as being 2.0, determined according to Reference Example 12. The resulting material displayed a water uptake of 11.5 weight-%, determined as described in Reference Example 7. The Lewis acidity was determined according to Reference Example 1, whereby the integral extinction units of the IR bands of the Lewis acid sites were determined as being 9.95, and whereby the integral extinction units of the IR band at 1490 cm.sup.−1 at a pressure of 1 mbar were determined as being 1.6. Further, no Brønstedt acid sites were observed, determined according to Reference Example 1. In addition, the Lewis acid site density was determined by temperature-programmed-desorption of ammonia according to Reference Example 5. Thus, the Lewis acid site density was determined via NH.sub.3-TPD as being 0.19 mmol/g at a temperature below 200° C., no Lewis acid sites were observed in the temperature region between 200 to 400° C., and the Lewis acid site density of 0.02 mmol/g was observed at a temperature above 500° C.

EXAMPLE 25: CATALYTIC TESTINGS

Example 25.1: Preliminary Test—PO Test

[0386] Moldings of the examples were preliminarily tested with respect to their general suitability as epoxidation catalysts according to the PO test as described in Reference Example 8. The respective resulting values of the propylene oxide activity are shown in Table 2 below.

TABLE-US-00002 TABLE 2 Results for catalytic testing according to Reference Example 8 Integral Integral Molding propylene extinction units extinction units according oxide of Lewis acid of band at to # activity/% bands 1490 cm.sup.−1 Ref. Ex. 14 7.88 56.2 6 Ref. Ex. 15 7.96 24.8 3.9 Ref. Ex. 16 8.34 27.5 4.3 Ref. Ex. 17 8.9 14.2 Ref. Ex. 18 6.1 100.7 9.77 Ref. Ex. 19 6.47 108.9 11.05 Ref. Ex. 20 6.99 118.3 11.53 Comp. 9.5 77.8 8.1 Example 22

[0387] Obviously, the molding according to Comparative Example 22 exhibits a very good propylene oxide activity according to the PO test. Therefore, it can be expected that also the moldings according to the present invention are promising candidates for catalysts in industrial continuous epoxidation reactions.

Example 25.2: Continuous Epoxidation of Propylene

[0388] a) Results for Comparative example 22, as shown in FIG. 1 [0389] The conversion was observed to be about 99% for the first 200 hours of the testing time, then dropped to about 95% at around 400 hours, and then increased again to about 99% before decreasing within about 1500 hours to about 86%. After reaching a maximum of about 98% conversion for about 50 hours after 2000 hours the conversion then decreased below 84%. The selectivity towards propylene oxide based on H.sub.2O.sub.2 was in a range of from about 97 to about 99% over the whole run time. The selectivity towards propylene oxide based on propene (C3) was in the range of from about 99% to almost 100% over the whole run time. The temperature was in a range of from about 32 to about 37° C. over the whole run time.

[0390] b) Results for Reference example 20, as shown in FIG. 2 [0391] The total run time was about 500 hours. The conversion was observed to be in the range of from about 87 to 96%, reaching the maximum after about 320 hours and the minimum after about 50 hours and also after about 360 hours. The selectivity towards propylene oxide based on H.sub.2O.sub.2 was in a range of from about 97 to about 98% over the whole run time. The selectivity towards propylene oxide based on propene (C3) was in the range of from about 97 to about 99% over the whole run time. The temperature increased from about 35 to about 44° C. within the whole run time.

[0392] c) Results for Example 23, as shown in FIG. 3 [0393] The total run time was about 900 hours. The conversion was observed to be at least 92% over the whole run time, whereby the conversion was about 99% for about the first 250 hours, then decreased slowly to a minimum of 92% before increasing again. The selectivity towards propylene oxide based on H.sub.2O.sub.2 was about 99% over the whole run time. The selectivity towards propylene oxide based on propene (C3) was in the range of from about 99% to almost 100% over the whole run time. The temperature was about 35° C. over the whole run time. [0394] In summary, the molding of the present invention is especially suitable in industrial-scale processes as regards the continuous epoxidation reaction of propene and, thus, interesting for commercial purposes, since it has convincingly been shown that the molding of the present invention according to Example 23 is an ideal catalyst, allowing, at a constantly high conversion of at least 92%, for excellent selectivities with regard to propylene oxide, in particular with regard to propylene oxide based on propene. [0395] In particular, it has been shown that compared to a molding representing the prior art according to Reference Example 20 as discussed under item b) hereinabove, the molding of the present invention showed a conversion of at least 92%, whereas the conversion observed for Reference Example 20 was in the range of from about 87 to 96%, not to mention that a higher temperature was necessary to achieve said result. Further, the selectivity based on H.sub.2O.sub.2 as well as based on propene was higher for the inventive molding over the whole run time. [0396] Similarly, the molding according to Example 23 showed an improved conversion within the first about 250 hours of the testing at a high level of about 99%, whereas the molding according to Comparative Example 22 as discussed under item a) hereinabove showed a conversion that is decreasing especially within a run time of 200 to 250 hours.

BRIEF DESCRIPTION OF FIGURES

[0397] FIG. 1: shows the results of the continuous epoxidation reaction according to Reference Example 9 for the molding of Comparative Example 22 in terms of the valuable product propylene oxide and the hydrogen peroxide conversion. The selectivity S (PO) H.sub.2O.sub.2 in % for propylene oxide based on H.sub.2O.sub.2 (mid-grey graph) is defined as moles of propylene oxide formed per unit time divided by moles of H.sub.2O.sub.2 consumed per unit time×100. The selectivity S (PO) C3 in % for propylene oxide based on propylene (light-grey line) is defined as moles of propylene oxide formed per unit time divided by moles of propylene consumed per unit time ×100. The conversion C in % (left ordinate) of H.sub.2O.sub.2 is defined as moles of H.sub.2O.sub.2 consumed per unit time divided by moles of H.sub.2O.sub.2 fed to the reactor per unit time ×100. The inlet temperature T in ° C. (right ordinate) is the inlet temperature of the heat-transfer medium. The time on stream t in hours is given on the abscissa. The starting point (t=0) is taken as the time at which the H.sub.2O.sub.2 metering pump is started (all other pumps are started earlier).

[0398] FIG. 2: shows the results of the continuous epoxidation reaction according to Reference Example 9 for the molding of Reference Example 20 in terms of the valuable product propylene oxide and the hydrogen peroxide conversion. The selectivity S (PO) H.sub.2O.sub.2 in % for propylene oxide based on H.sub.2O.sub.2 (mid-grey graph) is defined as moles of propylene oxide formed per unit time divided by moles of H.sub.2O.sub.2 consumed per unit time ×100. The selectivity S (PO) C3 in % for propylene oxide based on propylene (light-grey line) is defined as moles of propylene oxide formed per unit time divided by moles of propylene consumed per unit time ×100. The conversion C in % (left ordinate) of H.sub.2O.sub.2 is defined as moles of H.sub.2O.sub.2 consumed per unit time divided by moles of H.sub.2O.sub.2 fed to the reactor per unit time ×100. The inlet temperature T in ° C. (right ordinate) is the inlet temperature of the heat-transfer medium. The time on stream t in hours is given on the abscissa. The starting point (t=0) is taken as the time at which the H.sub.2O.sub.2 metering pump is started (all other pumps are started earlier).

[0399] FIG. 3: shows the results of the continuous epoxidation reaction according to Reference Example 9 for the molding of Example 23 in terms of the valuable product propylene oxide and the hydrogen peroxide conversion. The selectivity S (PO) H.sub.2O.sub.2 in % for propylene oxide based on H.sub.2O.sub.2 (mid-grey graph) is defined as moles of propylene oxide formed per unit time divided by moles of H.sub.2O.sub.2 consumed per unit time ×100. The selectivity S (PO) C3 in % for propylene oxide based on propylene (light-grey line) is defined as moles of propylene oxide formed per unit time divided by moles of propylene consumed per unit time ×100. The conversion C in % (left ordinate) of H.sub.2O.sub.2 is defined as moles of H.sub.2O.sub.2 consumed per unit time divided by moles of H.sub.2O.sub.2 fed to the reactor per unit time ×100. The inlet temperature T in ° C. (right ordinate) is the inlet temperature of the heat-transfer medium. The time on stream t in hours is given on the abscissa. The starting point (t=0) is taken as the time at which the H.sub.2O.sub.2 metering pump is started (all other pumps are started earlier).

CITED LITERATURE

[0400] CN 105854933 A [0401] CN 106115732 A [0402] Y. Yu et al. “Insights into the efficiency of hydrogen peroxide utilization over titanosilicate/H.sub.2O.sub.2 systems” in Journal of Catalysis 2020, vol. 381, p. 96-107