Process for the production of a titanium silicalite shaped article

• US 8,449,812 B2
• Filed: 03/21/2001
• Issued: 05/28/2013
• Est. Priority Date: 03/29/2000
• Status: Expired due to Term

• Current Assignee: Evonik Operations GmbH (Rag-Stiftung)
• Original Assignee: Evonik Degussa GmbH (Rag-Stiftung)
• Inventors: Hasenzahl, Steffen, Jantke, Ralf
• Primary Examiner(s): HOFFMANN, JOHN M
• Application Number:
  US10/204,306
• Publication Number:
  US 20030130116A1
• Time in Patent Office: 4,451 Days
• Field of Search: 502/242, 264/621, 264/623
• US Class Current: 264/621
• CPC Class Codes: B01J 29/89 Silicates, aluminosilicates or borosilicates of titanium, zirconium or hafnium B01J29/005 takes precedence
• CPC Class Codes: B01J 37/0009 Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst
• CPC Class Codes: B01J 37/0018 Addition of a binding agent or of material, later completely removed among others as result of heat treatment, leaching or washing,(e.g. forming of pores; protective layer, desintegrating by heat)
• CPC Class Codes: C07C 249/04 of oximes
• CPC Class Codes: C07D 301/12 with hydrogen peroxide or inorganic peroxides or peracids

Abstract

A process for the production of a titanium silicalite shaped article by: a) preparation of a synthesis gel containing a Si₂ source, a Ti₂ source, a template compound and water, b) crystallization of the synthesis gel under hydrothermal conditions, c) drying of the titanium silicalite from step b) at a temperature below the decomposition temperature of the template compound, d) preparation of a formable mass containing the product from step c), a binder and a paste-forming agent, e) forming of the mass from step d) into a green shaped article, f) optionally drying, and g) calcinations of the green shaped article, as well as a titanium silicalite shaped article obtainable according to this process, and the use of this shaped article as a catalyst in epoxidation or ammoximation reactions.

Claims

1. Process for the production of a titanium silicalite shaped article comprising:

a) preparing a synthesis gel containing a SiO₂ source, a TiO₂ source selected from the group consisting of tetraalkylorthotitanates and silicon-titanium mixed oxides obtainable by flame hydrolysis of a mixture of SiCl₄ and TiCl₄, a template compound and water,

b) crystallizing the synthesis gel under hydrothermal conditions to obtain a crystal suspension containing titanium silicalite,

c) drying the titanium silicalite from step b) at a temperature below the decomposition temperature of the template compound,

d) preparing a formable mass containing a binder, a paste-forming agent and product from step c), said product being non-calcined and containing said template compound,

e) forming of the mass from step d) into a green shaped article, said mass being not yet calcined,

f) optionally drying, and

g) calcining the green shaped article to thereby remove said template compound,

characterized in that the template compound is chosen in a way that the titanium silicalite obtained by step b) exhibits MFI, MEL or β

-zeolite structure and the calcination step takes place after the formation of the green shaped article.

2. Process according to claim 1, wherein said crystal suspension from step b) is optionally neutralized, and said titanium silicalite is separated using a solid-liquid separation process before step c).

3. Process according to claim 1, wherein said titanium silicalite from step b) is dried directly according to step c) without prior separation .

4. Process according to claim 3, wherein the process further comprises between steps b) and c) a step of distilling off volatile constituents or adding titanium silicalite or both.

5. Process according to claim 4, wherein the crystal suspension has a solids content before the drying step c) of at least 50 wt. %.

6. Process according to claim 1, wherein an aqueous medium that optionally contains a water-miscible organic solvent is used as said paste-forming agent.

7. Process according to claim 1, wherein the drying temperature in step c) is within the range of 50°

to less than 400°

C.

8. Process according to claim 1, wherein a compound of silicon, aluminum, boron, phosphorus, zirconium or titanium is used as said binder.

9. process according to claim 8, wherein the binder is selected from the group consisting of aluminum oxide, silicon oxide, hydrolysable silicon compounds and partial or total hydrolysates thereof, boron compounds, phosphorus compounds, clay minerals and mixtures thereof.

10. Process according to claim 1, wherein said calcining of the green shaped article takes place at a temperature from 400°

C. to 1000°

C.

11. The process according to claim 10 wherein said calcining takes place at a temperature of 500°

C. to 750°

C.

12. Process for the production of a titanium silicalite shaped article comprising:

a) preparing a synthesis gel containing a SiO₂ source, a TiO₂ source selected from the group consisting of tetraalkylorthotitanates and silicon-titanium mixed oxides obtainable by flame hydrolysis of a mixture of SiC1₄ and TiC1₄, a template compound and water,

b) crystallizing the synthesis gel under hydrothermal conditions to obtain a crystal suspension containing titanium silicalite,

c) concentrating the crystal suspension from step b) to form a concentrated crystal suspension,

d) preparing a formable mass containing the concentrated crystal suspension from step c) and a binder,

e) forming of the formable mass from step d) into a green shaped article, said mass being not yet calcined,

f) optionally drying, and

g) calcining the green shaped article to thereby remove the template compound,

characterized in that the template compound is chosen in a way that the titanium silicalite obtained by step b) exhibits MFI, MEL or β

-zeolite structure and the titanium silicalite is not calcined prior to formation of the green shaped article.

13. Process according to claim 12, wherein said concentrated crystal suspension has a solids content after the concentration in step c) of 10-50 wt. %.