Modification method of titanium-silicalite zeolite based on the mixture of quaternary ammonium salt and inorganic alkali

Patent metadata

Field	Value
Publication number	US-9486790-B2
Application number	US-201214355157-A
Country	US
Kind code	B2
Filing date	Mar 18, 2012
Priority date	Oct 31, 2011
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

This invention relates to a modification method for titanium-silicalite zeolite (TS-1). The feature of the invention is pretreating the TS-1, after that the TS-1 is modified by the mixture of quaternary ammonium salts and inorganic base. The quaternary ammonium salts mentioned above include tetrapropylammonium fluoride, tetrapropylammonium chloride, tetrapropylammonium iodide and their mixture. The inorganic base includes LiOH, NaOH and KOH and their mixtures. TS-1 after the modification is aftertreated at last. The invention is universal capable to modify the TS-1 synthesized by any method, especially the TS-1 made with a low cost method. The modification can enhance the catalytic performance on both gas and liquid phase epoxidation of propylene.

First claim

We claim:

1. A modification method of Titanium-silicalite (TS-1) comprising:
providing an amount of TS-1;
pretreating the TS-1 by performing calcination of the TS-1 either under atmosphere or protective gas, wherein a calcination temperature is between 300 to 700° C., and a calcination time is between 30 min to 200 h;
performing modification of the TS-1 using a mixture of quaternary ammonium salts and inorganic alkali, wherein the quaternary ammonium salts are selected from the group consisting of tetrapropylammonium fluoride, tetrapropylammonium chloride, tetrapropylammonium iodide and combinations thereof, and wherein the inorganic alkali are selected from the group consisting of LiOH, NaOH, KOH and combinations thereof, and the treatment is performed in a reactor at a temperature between 50 and 250° C. for 2 h to 10 days; and
performing aftertreatment of the TS-1 by a process of separation, washing, and drying, wherein washing is carried out with deionized water and the drying is performed under atmosphere or protective gas at a temperature between 200 and 500° C. for 1 to 100 h.

2. The method of claim 1 , in the calcination temperature is between 400 and 600° C., and the calcination time is between 3 h to 24 h during the step of pretreating.

3. The method of claim 1 , wherein a ratio of TS-1 to TPAOH to salts to H 2 O is TS-1/g:TPAOH/mol:salts/g:H 2 O/g=50:0.005-50:0.05-5:200-2000 during the step of modification.

4. The method of claim 1 , wherein the pH of the TS-1 is adjusted to a value between 7 and 9 during the step of aftertreatment.

5. The method of claim 1 , wherein a calcination step is performed after drying during the aftertreatment step at a temperature between 200 and 500° C. for 30 min to 100 h.

Assignees

• Guo Hongchen
• Su Ji
• Liu Guanghong
• Univ Dalian Tech

Inventors

• Guo Hongchen
• Su Ji
• Liu Guanghong

Classifications

• C01B37/005

  Silicates, i.e. so-called metallosilicalites or metallozeosilites · CPC title

• C07D303/04

  containing only hydrogen and carbon atoms in addition to the ring oxygen atoms · CPC title

• B01J2229/34

  Reaction with organic or organometallic compounds · CPC title

• B01J29/035

  {Microporous crystalline materials not having base exchange properties, such as} silica polymorphs, e.g. silicalites · CPC title

• B01J2229/183

  in framework positions · CPC title