PROCESS FOR PREPARING A BORON CONTAINING ZEOLITIC MATERIAL HAVING MWW FRAMEWORK STRUCTURE

Abstract

A process for preparing an aluminum-free boron containing zeolitic material comprising the framework structure MWW (BMWW), comprising (a) hydrothermally synthesizing the BMWW from a synthesis mixture containing water, a silicon source, a boron source, and an MWW template compound obtaining the BMWW in its mother liquor, the mother liquor having a pH above 9; (b) adjusting the pH of the mother liquor, obtained in (a) and containing the BMWW, to a value in the range of from 6 to 9; (c) separating the BMWW from the pH-adjusted mother liquor obtained in (b) by filtration in a filtration device.

Claims

1. An aluminum-free boron containing zeolitic material comprising the framework structure MWW (BMWW), obtained by a process comprising (a) hydrothermally synthesizing a BMWW precursor from a synthesis mixture containing water, a silicon source, a boron source, and an MWW template compound obtaining the BMWW precursor in its mother liquor, the mother liquor having a pH above 9; (b) adjusting the pH of the mother liquor, obtained in (a) and containing the BMWW precursor, to a value in the range of from 6 to 9; (c) separating the BMWW precursor from the pH-adjusted mother liquor obtained in (b) by filtration in a filtration device. and being contained in a spray powder wherein at least 99 weight-% of the spray powder consist of the BMWW, wherein the BMWW has boron content in the range of from 1.0 to 2.2 weight-%, calculated as elemental boron and based on the total weight of the BMWW, a silicon content of at least 37 weight-%, calculated as elemental silicon and based on the total weight of the BMWW, a degree of crystallinity of at least (80 ?5) %, as determined via XRD, and a BET specific surface area of at least 300 m.sup.2/g, as determined according to DIN 66131.

2. The BMWW of claim 1, wherein the BET specific surface area is in the range of from 300 to 500 m.sup.2/g, as determined according to DIN 66131.

3. A catalyst, a catalyst support, or a catalyst precursor, comprising the aluminum-free boron containing zeolitic material according to claim 1.

4. The catalyst, catalyst support, or catalyst precursor according to claim 3, which is a catalyst precursor for the preparation of a titanium containing zeolitic catalyst.

5. The catalyst, catalyst support, or catalyst precursor according to claim 3, which is a catalyst precursor for the preparation of a zinc and titanium containing zeolitic catalyst.

Description

SHORT DESCRIPTION OF THE FIGURES

[0300] FIG. 1 shows a 20000:1 SEM (Scanning Electron Microscopy) picture (secondary electron (SE) picture at 5 kV (kiloVolt)) of the spray-dried and calcined B-MWW material as obtained according to Example 1. The scale is indicated in the lower right hand corner by the rule having a length of 1 micrometer.

[0301] FIG. 2 shows the X-ray diffraction pattern (copper K alpha radiation) of the spray-dried and calcined B-MWW material as obtained according to Example 1. On the x axis, the degree values (2 Theta) are shown, on the y axis, the intensity (Lin (Counts)).

[0302] FIG. 3 shows a 20000:1 SEM (Scanning Electron Microscopy) picture (secondary electron (SE) picture at 5 kV (kiloVolt)) of the spray-dried and calcined B-MWW material as obtained according to Comparative Example 1. The scale is indicated in the lower right hand corner by the rule having a length of 1 micrometer.

[0303] FIG. 4 shows the X-ray diffraction pattern (copper K alpha radiation) of the spray-dried and calcined B-MWW material as obtained according to Comparative Example 1. On the x axis, the degree values (2 Theta) are shown, on the y axis, the intensity (Lin (Counts)).

[0304] FIG. 5 shows the X-ray diffraction pattern (copper K alpha radiation) of the spray-dried and calcined B-MWW material as obtained according to Example 2. On the x axis, the degree values (2 Theta) are shown, on the y axis, the intensity (Lin (Counts)).

[0305] FIG. 6 shows a 20000:1 SEM (Scanning Electron Microscopy) picture (secondary electron (SE) picture at 5 kV (kiloVolt)) of the spray-dried and calcined B-MWW material as obtained according to Comparative Example 2. The scale is indicated in the lower right hand corner by the rule having a length of 1 micrometer.

[0306] FIG. 7 shows the X-ray diffraction pattern (copper K alpha radiation) of the spray-dried and calcined B-MWW material as obtained according to Comparative Example 2. On the x axis, the degree values (2 Theta) are shown, on the y axis, the intensity (Lin (Counts)).

[0307] FIG. 8 shows a 20000:1 SEM (Scanning Electron Microscopy) picture (secondary electron (SE) picture at 5 kV (kiloVolt)) of the spray-dried and calcined B-MWW material as obtained according to Example 3. The scale is indicated in the lower right hand corner by the rule having a length of 1 micrometer.

[0308] FIG. 9 shows the X-ray diffraction pattern (copper K alpha radiation) of the spray-dried and calcined B-MWW material as obtained according to Example 3. On the x axis, the degree values (2 Theta) are shown, on the y axis, the intensity (Lin (Counts)).

[0309] FIG. 10 shows the result of the determination of the Dv10, Dv50, and Dv90 values of the solid material particles contained in a typical mother liquor as obtained according to the recipe of Example 3. As to the parameters used for the determination, reference is made to Reference Example 2. On the x axis of each of the graphs (a), (b) and (c), the particle diameter/micrometer is shown. On the left and right y axis, the volume-% of the particles is shown. The values of the left y axis refer to the distribution containing the peak whereas the values of the right y axis refer to the distribution as indicated by the integral curve. The Dv10, Dv50, and Dv90 values of the individual measurement according to (a), (b) and (c) were as follows:

TABLE-US-00002 Dv10/ Dv50/ Dv90/ micrometer micrometer micrometer (a1) 3.02 4.97 8.16 (b1) 3.11 4.97 7.92 (c1) 3.11 4.97 7.91

[0310] FIG. 11 shows the result of the determination of the Dv10, Dv50, and Dv90 values of the solid material particles contained in a typical mother liquor as obtained according to Example 3 where the pH of the mother liquor was not adjusted. As to the parameters used for the determination, reference is made to Reference Example 2. On the x axis of each of the graphs (a), (b) and (c), the particle diameter/micrometer is shown. On the left and right y axis, the volume-% of the particles is shown. The values of the left y axis refer to the distribution containing the peak whereas the values of the right y axis refer to the distribution as indicated by the integral curve. The Dv10, Dv50, and Dv90 values of the individual measurement according to (a), (b) and (c) were as follows:

TABLE-US-00003 Dv10/ Dv50/ Dv90/ micrometer micrometer micrometer (a2) 2.89 4.66 7.02 (b2) 2.88 4.66 7.02 (c2) 2.83 4.75 7.39

CITED LITERATURE

[0311] WO 03/074421 A1 [0312] WO 03/074422 A1