Aluminophosphate-based zeolite membrane synthesis method

• US 11,008,219 B2
• Filed: 09/17/2019
• Issued: 05/18/2021
• Est. Priority Date: 03/31/2017
• Status: Active Grant

• Current Assignee: NGK Insulators Limited
• Original Assignee: NGK Insulators Limited
• Inventors: Hagio, Takeshi, Noda, Kenichi, Miyahara, Makoto, Shimizu, Katsuya
• Primary Examiner(s): Brunsman, David M
• Application Number:
  US16/572,786
• Publication Number:
  US 20200009509A1
• Time in Patent Office: 609 Days
• CPC Class Codes: B01D 2323/08 Specific temperatures applied
• CPC Class Codes: B01D 2323/082 Cooling
• CPC Class Codes: B01D 2323/21815 Acids
• CPC Class Codes: B01D 2323/24 Use of template or surface directing agents [SDA]
• CPC Class Codes: B01D 2323/48 Influencing the pH
• CPC Class Codes: B01D 53/9418 for removing nitrogen oxides by selective catalytic reduction [SCR] using a reducing agent in a lean exhaust gas
• CPC Class Codes: B01D 67/0051 by controlled crystallisation, e,.g. hydrothermal growth
• CPC Class Codes: B01D 69/105 Support pretreatment
• CPC Class Codes: B01D 69/108 Inorganic support material
• CPC Class Codes: B01D 69/12 Composite membranes; Ultra-thin membranes
• CPC Class Codes: B01D 71/028 Molecular sieves carbon B01D71/021
• CPC Class Codes: B01D 71/0281 Zeolites
• CPC Class Codes: B01J 29/50 of the erionite or offretite type, e.g. zeolite T, as exemplified by patent document US2950952
• CPC Class Codes: B01J 29/83 Aluminophosphates [APO compounds]
• CPC Class Codes: B01J 29/85 Silicoaluminophosphates [SAPO compounds]
• CPC Class Codes: B01J 35/59 Membranes
• CPC Class Codes: C01B 39/305 using at least one organic template directing agent
• CPC Class Codes: C01B 39/54 Phosphates, e.g. APO or SAPO compounds

Abstract

A method of synthesis for an aluminophosphate-based zeolite membrane includes a steps of preparing a mixed solution with a pH greater than or equal to 6 and less than or equal to 9 by mixing an acidic phosphorous source with an alkali source, a steps of preparing a starting material solution by adding and mixing an aluminum source to the prepared mixed solution, and a steps of synthesizing an aluminophosphate-based zeolite membrane by hydrothermally synthesizing the starting material solution.

Claims

1. A method of synthesis for an aluminophosphate-based zeolite membrane comprising:

preparing a mixed solution with a pH greater than or equal to 6 and less than or equal to 9 by mixing an acidic phosphorous source with an alkali source;

preparing a starting material solution by adding and mixing an aluminum source to the prepared mixed solution; and

synthesizing an aluminophosphate-based zeolite membrane by hydrothermally synthesizing the starting material solution.

2. The method of synthesis for an aluminophosphate-based zeolite membrane according to claim 1,

wherein in the step of preparing the starting material solution, the mixed solution is configured to be less than or equal to a temperature that enables suppression of a reaction of the aluminum source with the phosphorous source in the mixed solution.

3. The method of synthesis for an aluminophosphate-based zeolite membrane according to claim 2,

wherein in the step of preparing the starting material solution, the mixed solution has a temperature of less than or equal to 40 degrees C.

4. The method of synthesis for an aluminophosphate-based zeolite membrane according to claim 2,

wherein in the step of preparing the starting material solution, the mixed solution has a temperature of less than or equal to 25 degrees C.

5. The method of synthesis for an aluminophosphate-based zeolite membrane according to claim 2,

wherein in the step of preparing the starting material solution, the mixed solution has a temperature of less than or equal to 10 degrees C.

6. The method of synthesis for an aluminophosphate-based zeolite membrane according to claim 2,

wherein in the step of preparing the starting material solution, the mixed solution has a temperature of less than or equal to 5 degrees C.

7. The method of synthesis for an aluminophosphate-based zeolite membrane according to claim 1,

wherein in the step of preparing the mixed solution, the alkali source is an organic amine-type structure-directing agent.

8. The method of synthesis for an aluminophosphate-based zeolite membrane according to claim 7,

wherein the aluminum source is aluminum alkoxide or an alumina sol.

9. The method of synthesis for an aluminophosphate-based zeolite membrane according to claim 1,

wherein the aluminophosphate-based zeolite membrane is configured by an AlPO-based or SAPO-based zeolite.

10. The method of synthesis for an aluminophosphate-based zeolite membrane according to claim 9,

wherein the aluminophosphate-based zeolite membrane is configured by a zeolite that has pores that are formed from an oxygen 8-membered ring.

11. The method of synthesis for an aluminophosphate-based zeolite membrane according to claim 1,

wherein a molar ratio of H₂O to T atoms, which are atoms positioned at the center of the oxygen tetrahedron that forms the aluminophosphate-based zeolite membrane, in the starting material solution is greater than or equal to 30.