Direct incorporation of iron complexes into SAPO-34 (CHA) type materials

Patent metadata

Field	Value
Publication number	US-9868116-B2
Application number	US-201615009955-A
Country	US
Kind code	B2
Filing date	Jan 29, 2016
Priority date	Jan 29, 2015
Publication date	Jan 16, 2018
Grant date	Jan 16, 2018

Abstract

Fe-SAPO-34 silicoaluminophosphates having Fe 2+ organic complexes and methods for their direct synthesis in the absence of a co-templating agent are described. Fe-SAPO-34 silicoaluminophosphate having Fe 3+ located in extra-framework locations within the pores of cages of the crystal are described. They are prepared by calcining the Fe-SAPO-34 silicoaluminphosphates containing Fe 2+ polyamine complexes. Methods of using the Fe-SAPO-34 having Fe 3+ located in extra-framework locations within the pores of cages of the crystal in the treatment of exhaust gases are described.

First claim

We claim:

1. An Fe-SAPO-34 silicoaluminophosphate, wherein the Fe is only present as Fe 2+ when analyzed by Mössbauer spectroscopy and UV-visible spectroscopy and the Fe 2+ is in extra-framework locations and the Fe-SAPO-34 silicoaluminophosphate has not been calcined.

2. The Fe-SAPO-34 silicoaluminophosphate of claim 1 , wherein the Fe 2+ is present in a polyamine complex.

3. The Fe-SAPO-34 silicoaluminophosphate of claim 2 , wherein the Fe 2+ is present in two environments when analyzed by Mössbauer spectroscopy, with one environment having an isomer shift at about 1.15 mm s −1 and another environment having an isomer shift at about 0.87 mm s −1 .

4. The Fe-SAPO-34 silicoaluminophosphate of claim 3 , wherein the Fe 2+ in the phase having an isomer shift at about 1.15 mm s −1 represents over 50% of the Fe 2+ in the Fe-SAPO-34 silicoaluminophosphate.

5. The Fe-SAPO-34 silicoaluminophosphate of claim 1 , said silicoaluminophosphate having a solid state UV-Vis absorption spectrum with an absorbance maximum at about 550 nm.

6. An Fe-SAPO-34 silicoaluminophosphate that in its calcined state comprises Fe 3+ or a mixture of Fe 2+ and Fe 3+ , wherein the Fe 3+ is present in an amount greater than or equal to 90% of the total amount of Fe in the calcined Fe-SAPO-34 silicoaluminophosphate, and the calcined Fe-SAPO-34 silicoaluminophosphate is substantially free from Fe 0 and the Fe cations are located mainly in the extra-framework positions.

7. The calcined Fe-SAPO-34 silicoaluminophosphate of claim 6 , wherein the Fe 3+ is present in an amount greater than or equal to 95% of the total amount of Fe in calcined Fe-SAPO-34 silicoaluminophosphate.

8. The Fe-SAPO-34 silicoaluminophosphate of claim 6 , wherein Fe +3 is present in the calcined solid at from greater than 0% to 5% based on the weight of the composition.

9. A calcined Fe-SAPO-34 silicoaluminophosphate that in its calcined state comprises Fe 3+ or a mixture of Fe and Fe 3+ , wherein the Fe 3+ is present in an amount greater than or equal to 90% of the total amount of Fe in the calcined Fe-SAPO-34 silicoaluminophosphate, and the calcined Fe-SAPO-34 silicoaluminophosphate is substantially free from Fe 0 , said silicoaluminophosphate having a solid state UV-Vis absorption spectra having a continual decrease in absorption from 450 nm to 700 nm.

10. The calcined Fe-SAPO-34 silicoaluminophosphate of claim 9 , wherein the Fe 3+ is present in an amount greater than or equal to 95% of the total amount of Fe in calcined Fe-SAPO-34 silicoaluminophosphate.

11. The Fe-SAPO-34 silicoaluminophosphate of claim 9 , wherein Fe +3 is present in the calcined solid at from greater than 0% to 5% based on the weight of the composition.

12. A method of preparing a Fe-SAPO-34 silicoaluminophosphate where the Fe is only present as Fe′ when analyzed by Mössbauer spectroscopy and the Fe 2+ is located in extra-framework locations, the method comprising forming a mixture of phosphoric acid, silica, aluminium hydroxide, water, an organic linear polyamine and an iron salt.

13. The method of claim 12 , wherein the mixture does not comprise a co-templating agent.

14. The method of claim 12 , wherein the organic linear polyamine is diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA), pentaethylenehexamine (PEHA), or mixtures thereof.

15. The method of claim 12 , wherein the Fe-SAPO-34 silicoaluminophosphate formed has a purple color.

16. A method of reducing the levels of NOx in an exhaust gas, the method comprising contacting an exhaust gas with an Fe-SAPO-34 silicoaluminophosphate of claim 6 .

17. A method of reducing the levels of NOx in an exhaust gas, the method comprising contacting an exhaust gas with an Fe-SAPO-34 silicoaluminophosphate of claim 9 .

Assignees

• Johnson Matthey Plc

Inventors

• Casci John Leonello
• Wright Paul A
• Turrina Alessandro

Classifications

• B01J2235/15

  X-ray diffraction · CPC title

• B01J2235/30

  Scanning electron microscopy; Transmission electron microscopy · CPC title

• B01J35/77

  Compounds characterised by their crystallite size · CPC title

• B01D2255/50

  Zeolites · CPC title

• B01D53/9413

  Processes characterised by a specific catalyst · CPC title