Tin-containing zeolitic material having an MWW-type framework structure

Patent metadata

Field	Value
Publication number	US-9371239-B2
Application number	US-201314072286-A
Country	US
Kind code	B2
Filing date	Nov 5, 2013
Priority date	Nov 5, 2012
Publication date	Jun 21, 2016
Grant date	Jun 21, 2016

Abstract

A tin containing zeolitic material having an MWW-type framework structure (Sn-MWW), having a tin content of at most 2 weight-%, calculated as element and based on the weight of the Sn-MWW, and having an X-ray diffraction pattern comprising peaks at 2 theta diffraction angles of (6.6±0.1)°, (7.1±0.1)°, and (7.9±0.1)°.

First claim

The invention claimed is:

1. A process for preparing a tin-containing zeolitic material having an MWW-type framework structure (Sn-MWW) comprising
(i) providing a boron-containing zeolitic material having an MWW framework structure comprising SiO 2 and B 2 O 3 (B-MWW);
(ii) deboronating the B-MWW by treating the B-MWW provided in (i) with a liquid solvent system having a pH in the range of from 5.5 to 8;
(iii) incorporating Sn into deboronated B-MWW obtained from (ii) by a process comprising
(iii.1) preparing an aqueous synthesis mixture containing the deboronated B-MWW obtained from (ii), an MWW template compound, and a tin source, wherein in the synthesis mixture, the molar ratio of Sn, calculated as SnO 2 , relative to Si, calculated as SiO 2 and contained in the deboronated B-MWW, is at most 0.015:1;
(iii.2) hydrothermally synthesizing a tin-containing zeolitic material having an MWW-type framework structure from the synthesis mixture obtained from (iii.1) thereby obtaining a tin-containing zeolitic material having an MWW-type framework structure in its mother liquor;
(iii.3) separating the tin-containing zeolitic material having an MWW-type framework structure obtained from (iii.2) from its mother liquor;

(iv) treating the tin-containing zeolitic material having an MWW-type framework structure obtained from (iii) with an aqueous solution having a pH of at most 5 thereby obtaining the Sn-MWW having an Sn content of at most 2 weight-%, calculated as element and based on the weight of the Sn-MWW, and optionally separating the Sn-MWW from the aqueous solution.

2. The process of claim 1 , wherein in (i), the B-MWW is provided by a process comprising
(a) hydrothermally synthesizing a B-MWW precursor from an aqueous synthesis mixture containing a silicon source, a boron source, and an MWW template compound, to obtain the B-MWW precursor in its mother liquor;
(b) separating the B-MWW precursor from its mother liquor, comprising drying the B-MWW precursor,
wherein in the synthesis mixture in (a),
the molar ratio of B, calculated as B 2 O 3 and contained in the boron source, relative to Si, calculated as SiO 2 and contained in the Si source, is in the range of from 0.4:1 to 0.6:1;
the molar ratio of the MWW template compound, relative to Si, calculated as SiO 2 and contained in the Si source, is in the range of from 0.8:1 to 1.7:1; and
the molar ratio of H 2 O relative to Si, calculated as SiO 2 and contained in the Si source, is in the range of from 12:1 to 20:1.

3. The process of claim 2 , wherein (b) further comprises calcination of the separated B-MWW precursor, wherein the calcination is carried out at a temperature in the range of from 400 to 800° C.

4. The process of claim 1 , wherein in (i), at least 99 weight-% of the framework structure of the B-MWW consists of B 2 O 3 and SiO 2 and the molar ratio B 2 O 3 :SiO 2 of the B-MWW is at least 0.03:1.

5. The process of claim 1 , wherein in (ii), the liquid solvent system is selected from the group consisting of water, methanol, ethanol, propanol, ethane-1,2-diol, propane-1,2-diol, propane-1,3-diol, propane-1,2,3-triol, and mixtures of two or more thereof, wherein the liquid solvent system does not contain an inorganic or organic acid, or a salt thereof.

6. The process of claim 1 , wherein in (ii), the weight ratio of the liquid solvent system relative to B-MWW is in the range of from 40:1 to 5:1, the treating is carried out at a temperature in the range of from 50 to 125° C., and for a period in the range of from 6 to 20 h.

7. The process of claim 1 , wherein in (ii), the treating is carried out in a closed system under autogenous pressure or in an open system under reflux.

8. The process of claim 1 , wherein (ii) further comprises drying the deboronated B-MWW at a temperature in the range of from 100 to 180° C.

9. The process of claim 1 , wherein (ii) further comprises calcination of the separated deboronated B-MWW, wherein the calcination is carried out at a temperature in the range of from 400 to 800° C.

10. The process of claim 1 , wherein the deboronated B-MWW has a molar ratio B 2 O 3 :SiO 2 of at most 0.01:1.

11. The process of claim 1 , wherein the tin source is selected from the group consisting of SnCl 4 , Sn(IV)-acetate, Sn(IV)-tert-butoxide, SnBr 4 , SnCl 4 , SnF 4 , Sn(IV)-bisacetylacetonate dichloride, Sn(IV)-bisacetylacetonate dibromide, Sn(II)-acetate, Sn(II)acetylacetonate, Sn(II)-citrate, SnCl 2 , SnF 2 , SnI 2 , SnSO 4 , and a mixture of two or more thereof.

12. The process of claim 1 , wherein in the aqueous synthesis mixture in (iii.1), the molar ratio of Sn, calculated as SnO 2 , relative to Si, calculated as SiO 2 and contained in the deboronated B-MWW, is in the range of from 0.001:1 to 0.015:1, the molar ratio of the MWW template compound relative to Si, calculated as SiO 2 and contained in the deboronated B-MWW, is in the range of from 1.0:1 to 2.0:1, and the molar ratio of H 2 O relative to Si, calculated as SiO 2 and contained in the deboronated B-MWW, is in the range of from 10:1 to 20:1.

13. The process of claim 1 , wherein the hydrothermal synthesizing according to (iii.2) is carried out at a temperature in the range of from 80 to 250° C., for a period in the range of from 20 to 200 h.

14. The process of claim 1 , wherein (iii.3) further comprises drying the tin-containing zeolitic material having an MWW-type framework structure, wherein the drying is carried out at a temperature in the range of from 100 to 180° C.

15. The process of claim 1 , wherein in (iii.3) and before (iv), the separated tin-containing zeolitic material having an MWW-type framework structure is not subjected to calcination.

16. The process of claim 1 , wherein in (iv), the aqueous solution comprises an organic acid selected from the group consisting of oxalic acid, acetic acid, citric acid, methane sulfonic acid, and a mixture of two or more thereof, and/or an inorganic acid selected from the group consisting of phosphoric acid, sulphuric acid, hydrochloric acid, nitric acid, and a mixture of two or more thereof, and wherein the aqueous solution has a pH in the range of from 0 to 5.

17. The process of claim 1 , wherein in (iv), the tin-containing zeolitic material having an MWW-type framework structure is treated with the aqueous solution at a temperature in the range of from 50 to 175° C., for a period in the range of from 1 to 40 h.

18. The process of claim 1 , wherein in (iv), the weight ratio of the aqueous solution relative to the tin-containing zeolitic material having an MWW-type framework structure is in the range of from 10:1 to 50:1.

19. The process of claim 1 , wherein in (iv), the treating is carried out in a closed system under autogenous pressure or in an open system under reflux.

20. The process of claim 1 , wherein the tin content of the Sn-MWW obtained from (iv), calculated as element and based on the weight of the Sn-MWW, is in the range of from 0.1 to 1.9 weight-%.

21. The process of claim 1 , wherein (iv) comprises drying the Sn-MWW, wherein the drying is carried out at a temperature in the range of from 100 to 180° C., and wherein (iv) comprises calcination of the separated and dried Sn-MWW, wherein the calcination is carried out at a temperature in the range of from 400 to 800° C., for a period in the range of from 1 to 20 h.

22. The process of claim 1 , further comprising
(v) preparing a moldable mixture comprising the Sn-MWW obtained from (iv), the moldable mixture optionally comprisi

Assignees

• Basf Se

Inventors

• Parvulescu Andrei-Nicolae
• Müller Ulrich
• Teles Joaquim Henrique
• Vautravers Nicolas
• Hinrichsen Bernd
• Cox Gerhard
• Jacubinas Richard

Classifications

• C01B39/48

  using at least one organic template directing agent · CPC title

• C01B39/06

  Preparation of isomorphous zeolites characterised by measures to replace the aluminium or silicon atoms in the lattice framework by atoms of other elements {, i.e. by direct or secondary synthesis} · CPC title

• C01B39/12

  the replacing atoms being {at least} boron atoms · CPC title

• B01J37/10

  in the presence of water, e.g. steam · CPC title

• B01J2229/40

  Special temperature treatment, i.e. other than just for template removal · CPC title