Process for preparing a nanometric zeolite Y

Patent metadata

Field	Value
Publication number	US-10894722-B2
Application number	US-201716335735-A
Country	US
Kind code	B2
Filing date	Sep 18, 2017
Priority date	Sep 23, 2016
Publication date	Jan 19, 2021
Grant date	Jan 19, 2021

Abstract

A process for preparing a nanometric zeolite Y of FAU structural type with a crystal size of less than 100 nm and an A/B ratio of greater than 2, by mixing, in aqueous medium, of at least one source AO2 of at least one tetravalent element A chosen from silicon, germanium and titanium, of at least one source BOb of at least one trivalent element B chosen from aluminum, boron, iron, indium and gallium, of at least one source C2/mO of an alkali metal or alkaline-earth metal C chosen from lithium, sodium, potassium, calcium and magnesium, where source C2/mO also includes at least one source of hydroxide ions, to obtain a gel, maturation and hydrothermal treatment of the gel.

First claim

The invention claimed is:

1. A process for preparing a nanometric zeolite Y of FAU structural type with a crystal size of less than 100 nm and an A/B ratio of greater than 2, said process comprising:
i) mixing, in an aqueous medium, at least one source AO 2 of at least one tetravalent element A chosen from silicon, germanium and titanium, alone or as a mixture, at least one source BO b of at least one trivalent element B chosen from aluminum, boron, iron, indium and gallium, alone or as a mixture, at least one source C 2/m O of an alkali metal or alkaline-earth metal C chosen from lithium, sodium, potassium, calcium and magnesium, alone or as a mixture, said source C 2/m O of alkali metal or alkaline-earth metal C also including at least one source of hydroxide ions, to obtain a gel, the reaction mixture having the following molar composition:
v AO 2 :w BO b :x C 2/m O: y H 2 O
v being 1 to 40,
w being 0.1 to 5,
x being 1 to 40,
y being 30 to 1000,
b being 1 to 3, b being an integer or rational number, and
m being equal to 1 or 2,

ii) maturing the gel obtained from step (i) at a temperature of −15° C. to 60° C., with or without stirring, for a time of 10 hours to 60 days,
iii) after at least 10 hours and less than 48 hours of maturation, single or repeated addition of at least one source AO 2 of at least one tetravalent element A chosen from silicon, germanium and titanium, alone or as a mixture, to said gel, the molar composition of the gel on conclusion of the addition being as follows:
v AO 2 :w BO b :x C 2/m O: y H 2 O
v being 5 to 50,
w being 0.1 to 5,
x being 1 to 40,
y being 200 to 1000,
b being 1 to 3, b being an integer or rational number, and
m being equal to 1 or 2,

iv) hydrothermal treatment of the gel obtained from step (iii) at a temperature of 20° C. to 200° C., at an autogenous reaction pressure, for a time of 1 hour to 14 days, to obtain crystallization of said nanometric zeolite Y of FAU structural type.

2. The process as claimed in claim 1 , in which A is silicon.

3. The process as claimed in claim 1 , in which B is aluminum.

4. The process as claimed in claim 1 , in which C is sodium.

5. The process as claimed in claim 1 , in which the reaction mixture from the mixing step (i) has the following molar composition:
v AO 2 :w BO b :x C 2/m O: y H 2 O
v being 15 to 20,
w being 0.2 to 1.5,
x being 1 to 20,
y being 100 to 400,
b being 1 to 3, b being an integer or rational number,
m being equal to 1 or 2.

6. The process as claimed in claim 1 , in which seeds comprising crystals of zeolite of FAU structural type are added during the mixing step (i).

7. The process as claimed in claim 1 , in which said mixing step (i) is performed in the absence of an organic structuring agent.

8. The process as claimed in claim 1 , in which said maturation step (ii) takes place at a temperature of 20 to 40° C., for a time of 10 hours to 30 days.

9. The process as claimed in claim 1 , in which the tetravalent element A added in the maturation step (iii) is identical to the tetravalent element A added in the mixing step (i).

10. The process as claimed in claim 1 , in which the single or repeated addition in said step (iii) of at least one source of at least one tetravalent element A is performed after at least 24 hours and less than 48 hours.

11. The process as claimed in claim 1 , in which the single or repeated addition in said step (iii) of at least one source of at least one tetravalent element A is performed after at least 12 hours and less than 48 hours.

12. The process as claimed in claim 1 , in which the molar composition of the gel on conclusion of the addition in step (iii) is as follows:
v AO 2 :w BO b :x C 2/m O: y H 2 O
v being 20 to 30,
w being 0.2 to 1.5,
x being 1 to 20,
y being 200 to 500,
b being 1 to 3, b being an integer or rational number,
m being equal to 1 or 2.

13. The process as claimed in claim 1 , in which the nanometric zeolite Y of FAU structural type formed on conclusion of step (iv) is filtered off, washed and then dried at a temperature of 20° C. to 150° C.

14. The process as claimed in claim 13 , in which said zeolite obtained on conclusion of the drying step undergoes at least one calcination step and at least one ion-exchange step.

15. The process as claimed in claim 1 , in which the tetravalent element A added in the maturation step (iii) is different from the tetravalent element A added in the mixing step (i).

16. The process as claimed in claim 1 , in which the single addition in said step (iii) of at least one source of at least one tetravalent element A is performed at 24 hours.

Assignees

• Ifp Energies Now

Inventors

• Dodin Mathias
• Bats Nicolas
• Patarin Joel
• Daou Jean
• Borel Maeva

Classifications

• C01B39/20

  Faujasite type, e.g. type X or Y · CPC title

• C01P2002/72

  by d-values or two theta-values, e.g. as X-ray diagram · CPC title

• C01P2002/60

  Compounds characterised by their crystallite size · CPC title

• B01J29/084

  Y-type faujasite · CPC title

• C01B39/205 Primary

  using at least one organic template directing agent; Hexagonal faujasite; Intergrowth products of cubic and hexagonal faujasite · CPC title