Catalyst preparation
View Patent ↗Titanium silicallite crystals useful as catalyst for the production of propylene oxide are prepared by forming a solution of a silicon component, a titanium component and a template, the mol ratio of template to silicon component being 0.25 or less and heating the solution to reaction temperature at a rate not to exceed 0.3° C./min.
1. A process for the preparation of titanium silicalite crystals useful as catalyst for the production of propylene oxide which comprises forming an aqueous solution of a silica source, a titanium source and a template, heating the said solution to a temperature in the range of 160-230° C. at the rate not to exceed 0.3° C./min, and maintaining the heated mixture at 160-230° C. for a time sufficient for the formation of titanium silicalite crystals.
2. A process for the preparation of titanium silicalite crystals useful as catalyst for the production of propylene oxide which comprises forming an aqueous solution of a silica source selected from the group consisting of tetra alkyl orthosilicates, alkoxy silicates, and silica, a titanium source selected from the group consisting of tetra alkyl orthotitanates, titanium alkoxy compounds, and Ti(IV) coordination complexes where the ligands include halogens, acetylacetonates or carboxylates and a quaternary ammonium compound template, the mol ratio of template to silica source not exceeding 0.25, heating the said solution to a temperature in the range of 160-230° C. at a rate not to exceed 0.3° C./min, and maintaining the heated mixture at 160-230° C. for a time sufficient for the formation of titanium silicalite crystals.
3. The process of claim 2 wherein the mol ratio of template to silica source is 0.10-0.18.
4. The process of claim 2 wherein tetraypropylammonium hydroxide is the template.
5. The process of claim 2 wherein the silica source is tetra alkyl orthosilicate.
6. The process of claim 2 wherein the titanium source is tetra alkyl orthotitanate.
7. The process for the production of propylene oxide which comprises oxidizing propylene using the catalyst prepared by the method of claim 2 .
8. A process for the preparation of titanium silicalite crystals useful as catalyst for the production of propylene oxide which comprises forming an aqueous solution of a tetra alkyl orthosilicate, a tetra alkyl orthotitanate, and a quaternary ammonium compound template, the mole ratio of template to tetra alky orthosilicate not exceeding 0.25, heating the said solution to a temperature in the range of 160-230° C. at a rate not to exceed 0.3° C./min, and maintaining the heated solution at 160-230° C. for a time sufficient for the formation of titanium crystals.