FR3081346A1 - PROCESS FOR THE PREPARATION OF A ZEOLITHIC COMPOSITE MATERIAL CONTAINING COPPER AND A MIXTURE OF STRUCTURAL TYPE ZEOLITHS AFX AND BEA STRUCTURAL TYPE - Google Patents

Abstract

The present invention relates to a process for the preparation of a zeolite composite material composed of a mixture of zeolites AFX and BEA and containing copper, comprising at least the following stages: i) the mixing in aqueous medium, in particular proportions, of at least one zeolite of structural type FAU, a nitrogenous organic compound R selected from 1,5-bis (methylpiperidinium) pentane dihydroxide, 1,6-bis (methylpiperidinium) hexane dihydroxide and dihydroxide of 1, 7-bis (methylpiperidinium) heptane, of at least one source of at least one alkali metal and / or alkaline earth metal M of valence n, n being an integer greater than or equal to 1, of at least one complexing agent and at least one source of copper, to obtain a gel, ii) the hydrothermal treatment of said gel obtained at the end of step i) at a temperature between 120 ° C and 220 ° C, for a period of time between 12 hours and 15 days.

Description

Technical area

The present invention relates to a process for the direct preparation of a composite material containing copper and an intimate mixture of a zeolite of structural type AFX and a zeolite of structural type BEA. This process allows direct synthesis of an AFX-BEA zeolitic composite material containing copper, by conversion / transformation under hydrothermal conditions of a zeolite of structural type FAU, used as a source of silicon and aluminum, in the presence of '' a specific organic molecule comprising two quaternary ammonium functions, also called structuring, chosen from 1,5-bis (methylpiperidinium) pentane, 1,6bis (methylpiperidinium) hexane and 1,7-bis (methylpiperidinium) heptane, in their dihydroxide form, and an organic copper complex, said organic copper complex being formed in situ in the presence of an organic complexing agent (OCPLX) and a source of copper. The present invention also relates to the zeolitic composite material itself. Said zeolitic composite material, containing a mixture of zeolites of AFX structural type and BEA structural type, and copper, obtained according to the process of the invention advantageously finds its application as a catalyst, adsorbent or separation agent.

Prior art

Microporous crystallized materials, such as zeolites or silicoaluminophosphates, are solids widely used in the petroleum industry as a catalyst, catalyst support, adsorbent or separation agent. Although many microporous crystal structures have been discovered, the refining and petrochemical industry is always looking for new zeolitic structures which have particular properties for applications such as purification or separation of gases, conversion of carbonaceous or other species.

AFX structural type zeolites include in particular the SSZ-16 zeolite, and related solids, called zeotypes, SAPO-56 and MEAPSO-56. An AFX structural type zeolite has a three-dimensional pore system bounded by eight tetrahedra and is formed by two types of cages: gmelinite (GME cage) and a large AFT cage (~ 8.3 x 13.0 A).

Many methods for synthesizing zeolites of the AFX structural type, in particular the SSZ-16 zeolite, are known. The SSZ-16 zeolite has been synthesized, for example, using nitrogenous organic species derived from 1,4-di (1-azoniabicyclo [2.2.2] octane) lower alkane compounds (US Patent 4,508,837). Chevron Research and Technology Company prepared the zeolite SSZ-16 in the presence of DABCO-C _n -diquat cations, where DABCO represents 1,4diazabicyclo [2.2.2] octane and n is 3, 4 or 5 (US Patent No 5,194,235 ). SB Hong et al. used the d6-diquaternary alkylammonium ion Et6-diquat-n, where Et6-diquat represents Ν ', Ν'-bis-triethylpentanediammonium and n is 5, as a structural agent for the synthesis of the zeolite SSZ-16 (Micropor. Mesopor Mat., 60 (2003) 237-249). Mention may also be made of the use of the cations 1,3bis (adamantyl) imidazolium as structuring agent for the preparation of zeolite of AFX structural type (RHArcher et al. In Microp. Mesopor. Mat., 130 (2010) 255-2265; Johnson Matthey Company W02016077667A1). Inagaki Satoshi et al., In application JP 2016169139 used divalent cations Ν, Ν, Ν ', Ν'-tétraarquirubicyclo [2.2.2] oct-7-ene-2,3: 05,6-dipyrrolidium substituted with alkyl groups to prepare the SSZ-16 zeolite. Chevron USA (WO2017 / 200607 A1) proposes to carry out the synthesis of an SSZ-16 zeolite using the dications: 1.1 '(1,4-cyclohexylenedimethylene) bis [1 -methylpiperidinium], 1.1' - (1 , 4cyclohexylenedimethylene) bis [1 -methylpyrrolidinium], 1,1 '- (1,4-cyclohexylene dimethylene) bis [1-ethylpyrrolidinium]. H.-Y. Chen et al. (Johnson Matthey Company, US 2018/0093897) used a mixture of cations containing at least 1,3bis (adamantyl) imidazolium and a neutral amine to prepare the JMZ-10 zeolite of structural type AFX in the absence of alkaline cations. H.-Y. Chen et al. (Johnson Matthey Company, US2018 / 0093259) used a mixture of cations containing an organic molecule chosen from 1,3-bis (adamantyl) imidazolium, N, Ndimethyl-3,5-dimethylpiperidinium, N, N-diethyl- cis-2,6-dimethylpiperidinium, N, N, N-1 -trimethyladamantylammonium, Ν, Ν, Ν-dimethylethylcyclohexylammonium and at least one alkaline earth metal cation to obtain the zeolite JMZ-7 of AFX structural type which has Al sites close to a synthesis containing alkaline cations.

The present invention relates to a process for the preparation of a zeolitic composite material composed of a mixture of zeolites of structural type AFX and of structural type BEA, and containing copper. The interest of the invention lies in the very nature of the composite material obtained, composed of two different zeolites, of the AFX structural type and of the BEA structural type, intimately mixed, and containing the copper element. The advantage of the present invention also lies in the high proportion (advantageously greater than or equal to 90% by mass) of the AFX-BEA mixture in said composite material obtained. The use of such a material can then be envisaged in different applications, for example as a catalyst, adsorbent or separation agent.

Summary of the invention

The present invention relates to a process for the preparation of a zeolitic composite material composed of a mixture of zeolites of structural type AFX and of structural type BEA and containing copper, comprising at least the following steps:

i) the mixture in aqueous medium, of at least one zeolite of structural type FAU having a molar ratio S1O2 (fau) / AI2O ₃ (fau) of between 2 and 200, of at least one organic nitrogen compound R chosen from 1.5bis dihydroxide (methylpiperidinium) pentane, 1.6bis dihydroxide (methylpiperidinium) hexane, 1.7bis dihydroxide (methylpiperidinium) heptane and mixtures thereof, of at least one source of at least one alkali metal and / or alkaline earth M of valence η, n being an integer greater than or equal to 1, of at least one organic complexing agent and at least one source of copper, to obtain a precursor gel, the reaction mixture having the composition following molar:

(SiO ₂ (fau)) / (AI2O ₃ (fau)) between 2 and 200;

H2O / (SlO2 (FAU)) between 1 and 100;

R / (SiO2 (FAU)) between 0.01 and 0.6;

M ₂ / _n O / (SiO ₂ (FAU)) between 0.005 and 0.7;

CuO / (SlO2 (FAU)) between 0.005 and 0.06;

OCPLX / CuO between 0.8 and 2;

in which S1O2 (fau) denotes the molar quantity of S1O2 supplied by the FAU zeolite, and AI2O3 (fau) denotes the molar quantity of AI2O3 supplied by the FAU zeolite, H ₂ O the molar quantity of water present in the reaction mixture, R the molar quantity of said nitrogenous organic compound, M ₂ / _n O being the molar quantity of M ₂ / _n O supplied by the FAU zeolite and by the source of alkali metal and / or alkaline earth metal, OCPLX is the molar quantity of organic complexing agent and CuO is the molar amount of CuO provided by the copper source;

ii) the hydrothermal treatment of said reaction mixture obtained at the end of step i) at a temperature between 120 ° C. and 220 ° C., lasting between 12 hours and 15 days.

The present invention also relates to a zeolitic composite material composed of a mixture of zeolites of structural type AFX and of structural type BEA and containing copper, said composite material having a zeolitic structure comprising:

- between 30 and 90% by mass of zeolite of AFX structural type, relative to the total mass of said composite material in its anhydrous form;

- between 10 and 70% by mass of zeolite of structural type BEA, relative to the total mass of said composite material in its anhydrous form;

said composite material comprising between 0.05 and 6% by mass of copper element, relative to the total mass of said composite material in its anhydrous form.

An advantage of the present invention lies in the particular material prepared, this material consisting of a composite material containing an intimate mixture of a zeolite of structural type AFX and a zeolite of structural type BEA, and containing copper.

Another advantage of the invention consists in carrying out the direct synthesis of said AFX-BEA composite material containing copper. The process according to the invention consists in fact in preparing said particular zeolitic composite material by direct conversion / transformation (that is to say in a single reaction step) under hydrothermal conditions of at least one zeolite of structural type FAU, of SiO ₂ / AI ₂ O ₃ ratio between 2 and 200, in the presence of a specific nitrogenous organic compound, also called organic structuring agent, chosen from 1.5bis (methylpiperidinium) pentane, 1,6-bis (methylpiperidinium) hexane and 1,7bis (methylpiperidinium) heptane, in their dihydroxide form, and of an organic complexing agent of copper.

Advantageously, the method according to the invention makes it possible to obtain a zeolitic composite material having a high proportion, advantageously greater than or equal to 90% by mass, of AFX and BEA zeolites, or even devoid of impurities and / or other crystalline or amorphous phases. than those of AFX and BEA zeolites.

In particular, the Applicant has discovered that the specific nitrogenous organic compound, used as a structuring agent and chosen from 1.5bis dihydroxide (methylpiperidinium) pentane, 1.6bis dihydroxide (methylpiperidinium) hexane and 1.7bis dihydroxide (methylpiperidinium ) heptane, when it is mixed with at least one zeolite of structural type FAU having a molar ratio SîO ₂ (fau) / AI ₂ O ₃ (fau) of between 2 and 200, with possibly an additional contribution of at least one additional source of at least one tetravalent element X, and / or at least one additional source of at least one trivalent element Y, in the presence of an organic copper complex formed in situ in the presence of an agent organic complexing agent (OCPLX) and a copper source, leads to the production of a precursor reaction mixture of a zeolitic composite material containing copper and a mixture of zeolites of structural type AFX and of structural type BEA, the said reaction mixture having a molar ratio of all the tetravalent elements, expressed in oxides (that is to say S1O2 + XO2), relative to all the trivalent elements, expressed in oxides (that is to say say AI ₂ O ₃ + Y ₂ O ₃ ), introduced into the reaction mixture, between 2 and 200, then in the production of a zeolitic composite material comprising copper and an intimate mixture of zeolites of structural type AFX and of BEA structural type, in high proportion (advantageously having a proportion in AFX-BEA mixture greater than or equal to 90% by mass). Any other crystalline or amorphous phase and / or any impurity is preferably absent from the solid obtained at the end of the preparation process according to the invention, that is to say from the zeolitic composite material composed of a mixture of zeolites of structural type AFX and of structural type BEA and containing copper.

Another advantage of the present invention is to allow the preparation of a precursor reaction mixture of an AFX-BEA composite material containing copper, having an identical SiO2 / AI ₂ O ₃ molar ratio, greater or less than the SiO ₂ molar ratio (fau / AI2O _{3 <F} au) of the starting FAU structural type zeolite. The preparation process according to the invention in fact makes it possible to adjust the SiO ₂ / AI ₂ O ₃ ratio of the precursor reaction mixture containing a zeolite of structural type FAU as a function of the possible additional supply within the reaction mixture of at least at least one additional source of silicon atoms and / or at least one additional source of aluminum atoms.

The method according to the invention also makes it possible to introduce tetravalent elements, expressed in their oxide form XO2, other than silicon, and / or trivalent elements, expressed in their oxide form Y ₂ O ₃ , other than aluminum, in the reaction mixture, and to adjust the molar ratio of all the tetravalent elements (SîO2 (fau) + XO2) compared to all the tetravalent elements (AI ₂ O ₃ (fau) + Y2O ₃ ), in the reaction mixture.

Detailed description of the invention

According to the invention, the terms “composite material”, “zeolitic composite material” and “AFX-BEA composite material containing copper” are synonymous and used interchangeably to designate a solid material composed of a mixture of zeolites of structural type AFX and of BEA structural type and containing copper, said composite material having a zeolitic structure comprising:

- Between 30 and 90% by mass, preferably between 40 and 80% by mass, of zeolite of AFX structural type, relative to the total mass of said composite material in its anhydrous form;

- between 10 and 70% by mass, preferably between 20 and 60% by mass, of zeolite of structural type BEA, relative to the total mass of said composite material in its anhydrous form;

said composite material comprising between 0.05 and 6% by mass, preferably between 0.5 and 5% by mass and more preferably between 1 and 4% by mass, of copper element, relative to the total mass of said composite material in its form anhydrous.

The AFX-BEA composite material containing copper according to the invention preferably has a mass ratio (AFX / BEA) of the AFX zeolite with respect to the BEA zeolite, present in said composite material, of between 0.4 and 9, preferably between 0.5 and 7.5 and more preferably still between 1 and 4.

Advantageously, the composite material according to the invention has a SiO ₂ / AI ₂ O ₃ molar ratio of between 2 and 100, preferably between 4 and 90 and more preferably between 6 and 80.

Advantageously, the BEA structural type zeolite of the composite material according to the invention is preferably a beta zeolite containing a mixture containing between 35 and 45% by mass, preferably 40% by mass, of polymorph A and between 55 and 65% by mass, preferably 60% by mass, of polymorph B.

According to the invention, the copper element is integrated into the structures of the AFX and BEA zeolites of the zeolitic composite material.

Advantageously, said composite material defined above is capable of being obtained by the preparation process according to the invention.

According to the invention, the terms “gel”, “precursor gel” are synonymous and correspond to the homogeneous reaction mixture obtained at the end of step i) of the process according to the invention.

According to the present invention, the expression "comprised between ... and ..." means that the values at the limits of the interval are included in the range of values described. If this was not the case and the boundary values were not included in the range described, such precision will be provided by the present description of the invention.

The present invention more specifically relates to a process for the preparation of a zeolitic composite material composed of a mixture of zeolites of structural type AFX and of structural type BEA and containing copper, comprising at least, in particular consisting of, the steps following:

i) the mixture in aqueous medium, of at least one zeolite of structural type FAU having a molar ratio SiO ₂ (fau) / AI ₂ O ₃ (fau) of between 2 and 200, of at least one organic nitrogen compound R , selected bis (methylpiperidinium) pentane, bis (methylpiperidinium) hexane, bis (methylpiperidinium) heptane and at least one alkali metal and / or one alkaline earth metal M of valence η, n being one of the dihydroxide dihydroxide dihydroxide mixtures thereof , from at least one source

1.5-

1.6-

1.7- of a whole number greater than or equal to 1, of at least one organic complexing agent and at least one source of copper, to obtain a precursor gel, the reaction mixture having the following molar composition:

(SiO ₂ (fau)) / (AI ₂ O ₃ (fau)) between 2 and 200; H ₂ O / (SiO ₂ (fau)) between 1 and 100; R / (SiO ₂ (fau)) between 0.01 and 0.6;

M ₂ / _n O / (SiO ₂ (fau)) between 0.005 and 0.7;

CuO / (SiO2 (fau)) between 0.005 and 0.06;

OCPLX / CuO between 0.8 and 2;

in which SiO ₂ (fau) is the molar amount of SiO ₂ provided by the FAU zeolite, AI2O3 (fau) is the molar amount of AI ₂ O ₃ provided by the FAU zeolite, H ₂ O the molar amount of water present in the reaction mixture, R the molar quantity of said organic nitrogen compound, M ₂ / _n O being the molar quantity of M ₂ / _n O provided by the FAU zeolite and by the source of alkali metal and / or alkaline earth metal, OCPLX is the molar quantity of organic complexing agent and CuO is the molar quantity of CuO supplied by the copper source;

ii) hydrothermal treatment of said gel obtained at the end of step i) at a temperature between 120 ° C and 220 ° C for a period of between 12 hours and 15 days.

Advantageously, the targeted zeolitic composite material, composed of a mixture of AFX and BEA zeolites and containing copper, crystallizes during the hydrothermal treatment of step ii) of the process according to the invention.

Step i) mixing

The preparation process according to the invention comprises a step i) of mixing, in an aqueous medium, at least one zeolite of structural type FAU having a molar ratio SiO ₂ (fau) / AI2O ₃ (fau) of between 2 and 200, at least one nitrogenous organic compound R, R being 1,5-bis (methylpiperidinium) pentane dihydroxide, 1,6-bis (methylpiperidinium) hexane dihydroxide and / or 1,7bis (methylpiperidinium) dihydroxide heptane , at least one source of at least one alkali metal and / or one alkaline earth metal M of valence η, n being an integer greater than or equal to 1, of at least one organic complexing agent and of minus a source of copper, the reaction mixture having the following molar composition:

(S1O2 (fau)) / (AI2O ₃ (fau)) between 2 and 200, preferably between 4 and 100;

H ₂ O / (SlO ₂ (FAU))

R / (SiO ₂ (fau))

M ₂ / _n O / (SiO ₂ (fau))

CuO / (SiO ₂ (fau))

OCPLX / CuO between 1 and 100, preferably between 5 and 60;

between 0.01 and 0.6, preferably between 0.05 and 0.5;

between 0.005 and 0.7, preferably between 0.01 and 0.5;

between 0.005 and 0.06, preferably between 0.006 and 0.05;

between 0.8 and 2, preferably between 0.8 and 1.5 and preferably between 0.9 and 1.2;

in which SiO ₂ (fau) is the molar amount of SiO ₂ provided by the FAU zeolite, AI ₂ O ₃ (fau) the molar amount of AI ₂ O ₃ provided by the FAU zeolite, H ₂ O the molar amount of water present in the reaction mixture, R the molar amount of said organic nitrogen compound, M ₂ / _n O the molar amount of M ₂ / _n O provided by the FAU zeolite and by the source of alkali metal and / or alkaline earth metal, OCPLX the molar amount of organic complexing agent and CuO the molar amount of CuO provided by the copper source.

According to the invention, at least one, preferably one, zeolite of structural type FAU having a SiO ₂ / AI ₂ O ₃ ratio of between 2 and 200, preferably between 4 and 100, is incorporated into the reaction mixture as a source. silicon and aluminum.

The starting FAU structural type zeolite can be obtained by any method known to those skilled in the art, such as by direct synthesis in the case of a FAU zeolite having a SiO ₂ / AI ₂ O ₃ molar ratio. less than 6 or by treatment with steam (steaming) and / or acid washings of a zeolite of structural type FAU having a molar ratio SiO ₂ / AI ₂ O ₃ less than 6 in the case of a FAU zeolite having a ratio SiO ₂ / AI ₂ O ₃ molar greater than or equal to 6. Said starting FAU structural type zeolite can be used in its sodium form or any other form. It can for example, before being implemented in the process according to the invention, undergo an exchange of part or all of its sodium cations with ammonium cations, followed or not by a calcination step. Among the sources of FAU with a SiO ₂ / AI ₂ O ₃ molar ratio of between 2 and 200, preferably between 4 and 100, may be mentioned the commercial Y type zeolites produced by Zeolyst and by TOSOH, for example the commercial zeolites CBV100 , CBV600, CBV712, CBV720, CBV760 and CBV780, and the commercial zeolites HSZ-320HOA, HSZ-350HUA, HSZ-360HUA and HSZ-385HUA.

According to the invention, step i) of mixing is carried out in an aqueous medium, that is to say in water, preferably deionized water. The amount of water in the reaction mixture of step i) of the process of the invention is advantageously such that the H ₂ O / (SiO _{2 (F} au)) molar ratio is between 1 and 100, preferably between 5 and 60, SiO _{2 (F} au) being the molar amount of SiO ₂ provided by the starting FAU zeolite, H ₂ O being the molar amount of water present in the reaction mixture.

According to the invention, the reaction mixture comprises at least one, preferably one, nitrogenous organic compound R, chosen from 1.5bis dihydroxide (methylpiperidinium) pentane, 1.6bis dihydroxide (methylpiperidinium) hexane, dihydroxide 1,7bis (methylpiperidinium) heptane and their mixtures, said compound being incorporated in the reaction mixture as a structuring agent. Preferably, the structuring agent R incorporated in the reaction mixture is 1,6bis dihydroxide (methylpiperidinium) hexane. The anion associated with the quaternary ammonium cations present in the structuring nitrogenous organic species is the hydroxide anion.

Advantageously, the structuring agent R is incorporated into the reaction mixture in such a way that the molar ratio (R / (SiO ₂ (fau))) between the molar amount of said organic nitrogen compound R and the molar amount of SiO ₂ provided by the FAU zeolite incorporated into the reaction mixture is between 0.01 and 0.6, preferably between 0.05 and 0.5.

According to the invention, at least one, preferably one, source of at least one alkali metal and / or an alkaline earth metal M of valence η, n being an integer greater than or equal to 1, is used in the reaction mixture of step i). Advantageously, the alkali and / or alkaline-earth metal M is chosen from lithium, potassium, sodium, magnesium, calcium and the mixture of at least two of these metals. Most preferably, M is sodium. Preferably, the source of at least one alkali and / or alkaline earth metal M is sodium hydroxide.

Advantageously, the quantity of alkali and / or alkaline-earth metal M of valence n, incorporated into the reaction mixture is such that the molar ratio M ₂ / _n O / (SiO2 (fau)) is between 0.005 and 0.7, preferably between 0.01 and 0.5, M ₂ / _n O being the molar amount of M ₂ / _n O provided by the FAU zeolite and by the source (s) of alkali metal and / or of alkali metal - earthy, SiO ₂ (fau) the molar amount of SiO ₂ provided by the FAU zeolite incorporated into the reaction mixture.

According to the invention, at least one, preferably one, source of copper is incorporated into the reaction mixture of step i). According to the invention, a source of copper is a species capable of releasing copper in solution, advantageously in reactive form, such as for example sulfates, nitrates, chlorides, oxalates, organometallic copper complexes or their mixtures. Preferably, the source of copper is chosen from copper sulphates and copper nitrates. Advantageously, the copper source is incorporated into the reaction mixture in such a way that the molar ratio (CuO / (SiO2 (fau))) between the molar quantity of copper provided by said copper source (s) and expressed in CuO oxide, and SiO ₂ (fau) the molar amount of SiO ₂ provided by the FAU zeolite is between 0.005 and 0.06, preferably between 0.006 and 0.05.

According to the invention, at least one, preferably one, organic complexing agent (OCPLX) is incorporated into the reaction medium, during step i) of the process according to the invention. This organic complexing agent will be able to react with the copper in solution, released by the copper source, to create an organic copper complex in situ. The organic complexing agent (OCPLX) according to the invention is advantageously triethylenetetramine (TETA) or tetraethylenepentamine (ΤΕΡΑ). Advantageously, the organic complexing agent is incorporated into the reaction mixture in such a way that the molar ratio (OCPLX / CuO) between the molar amount of complexing agent (OCPLX) and the molar amount of copper provided by said copper source, expressed in CuO oxide, is between 0.8 and 2, preferably between 0.8 and 1.5 and preferably between 0.9 and 1.2.

Step i) makes it possible to obtain a homogeneous precursor gel.

In a particular embodiment of the invention, the reaction mixture of step i) also comprises at least one additional source of an oxide XO2, X being a tetravalent element chosen from the group formed by silicon, germanium, titanium, preferably silicon, so that, in the reaction mixture, the molar ratio XO ₂ / SiO ₂ (fau) is between 0.001 and 1, preferably between 0.001 and 0.9 and more preferably between 0.001 and 0 , 01, and that the molar ratio (XO ₂ + SiO ₂ (fau)) / (AI ₂ O ₃ (fau)) is advantageously between 2 and 200, preferably between 4 and 100, XO ₂ being the molar amount of XO ₂ provided by the additional source of said oxide XO ₂ , SiO ₂ (fau) the molar amount of SiO ₂ provided by the FAU zeolite and AI ₂ O3 (fau) the molar amount of AI ₂ O ₃ provided by the FAU zeolite. Advantageously, in this embodiment, the molar composition of the reaction mixture is:

(XO ₂ + SiO ₂ (fau)) / AI ₂ O ₃ (fau) between 2 and 200, preferably between 4 and 100; H ₂ O / (XO ₂ + SîO ₂ (fau)) between 1 and 100, preferably between 5 and 60; R / (XO ₂ + SiO ₂ (fau)) between 0.01 and 0.6, preferably between 0.05 and 0.5; M ₂ / _n O / (XO ₂ + SiO ₂ (fau)) between 0.005 and 0.7, preferably between 0.01 and 0.5; CuO / (XO ₂ + SiO ₂ (fau)) between 0.005 and 0.06, preferably between 0.006 and 0.05;

OCPLX / CuO between 0.8 and 2, preferably between 0.8 and 1.5 and preferably between 0.9 and 1.2.

in which XO ₂ is the molar quantity of XO ₂ supplied by the additional source of said oxide XO ₂ , SiO _{2 (F} au) is the molar quantity of SiO ₂ supplied by the zeolite FAU, AI ₂ O ₃ (fau) the molar quantity of AI ₂ O ₃ provided by the FAU zeolite, H ₂ O the molar amount of water present in the reaction mixture, R the molar amount of said organic nitrogen compound, M _{2 / n} O the molar amount of M _{2 / n} O provided by the FAU zeolite and by the source of alkali metal and / or alkaline earth metal, OCPLX the molar amount of organic complexing agent and CuO the molar amount of CuO provided by the copper source.

In another particular embodiment of the invention, the reaction mixture of step i) also comprises at least one additional source of an oxide Y ₂ O ₃ , Y being a trivalent element chosen from the group formed by aluminum, boron and gallium, preferably aluminum, so that, in the reaction mixture, the molar ratio Y ₂ O ₃ / AI ₂ O _{3 (F} au) is between 0.001 and 10, preferably between 0.001 and 5, preferably between 0.001 and 4, and that the SiO ₂ (fau) / (AI ₂ O ₃ ( _F au) + ΥζΟ ₃ ) molar ratio is advantageously between 2 and 200, preferably between 4 and 100, SiO ₂ ( _F au) being the molar amount of SiO ₂ provided by the FAU zeolite, AI ₂ O _{3 (F} au) being the molar amount of AI ₂ O ₃ provided by the FAU zeolite and Y ₂ O ₃ the molar amount of Y ₂ O ₃ provided by the additional source of said oxide Y ₂ O ₃ . Advantageously, in this embodiment, the molar composition of the reaction mixture is:

SiO ₂ (fau) / (AI ₂ O ₃ (fau) + ΥζΟ ₃ ) between 2 and 200, preferably between 4 and 100;

H ₂ O / (SiO ₂ (fau)) between 1 and 100, preferably between 5 and 60;

R / (SiO ₂ (fau)) between 0.01 and 0.6, preferably between 0.05 and 0.5;

M ₂ / nO / (SiO ₂ (FAU))

CuO / (SiO ₂ (fau))

OCPLX / CuO between 0.005 and 0.7, preferably between 0.01 and 0.5;

between 0.005 and 0.06, preferably between 0.006 and 0.05;

between 0.8 and 2, preferably between 0.8 and 1.5 and preferably between 0.9 and 1.2;

in which SiO ₂ (fau) is the molar amount of SiO ₂ provided by the FAU zeolite, Y ₂ O ₃ is the molar amount of Y ₂ O ₃ provided by the additional source of said oxide Y ₂ O ₃ , AI ₂ O ₃ ( fau) the molar quantity of AI ₂ O ₃ provided by the zeolite FAU, H ₂ O the molar quantity of water present in the reaction mixture, R the molar quantity of said nitrogenous organic compound, M _{2 / n} O the molar quantity of M _{2 / n} O provided by the FAU zeolite and by the source of alkali metal and / or alkaline earth metal, OCPLX the molar amount of organic complexing agent and CuO the molar amount of CuO provided by the copper source.

In a third particular embodiment, the reaction mixture of step i) also comprises at least one additional source of an oxide XO ₂ , X being a tetravalent element chosen from the group formed by silicon, germanium, titanium , preferably silicon, and at least one additional source of an oxide Y ₂ O ₃ , Y being a trivalent element chosen from the group formed by aluminum, boron and gallium, preferably aluminum, such so that:

the reaction mixture of step i) advantageously contains between 20 and 95% by mass, preferably between 50 and 95% by mass, preferably between 60 and 90% by mass and even more preferably between 65 and 85% by mass, of zeolite structural type FAU with respect to the total mass of the trivalent and tetravalent elements of the mixture, in their oxide form;

the molar ratio XO ₂ / SiO ₂ (fau) in the reaction mixture is between 0.001 and 1, preferably between 0.001 and 0.9 and more preferably between 0.001 and 0.01;

the Y2O3 / AI2O3 molar ratio (fau) in the reaction mixture is between 0.001 and 10, preferably between 0.001 and, 5, preferably between 0.001 and 4; and the molar ratio (XO ₂ + SîO ₂ (fau)) / (AI ₂ O ₃ (fau) + Y2Û ₃ ) in the reaction mixture is between 2 and 200, preferably between 4 and 100,

XO ₂ being the molar amount of XO ₂ provided by the additional source of said oxide XO ₂ , SiO _{2 (F} au) being the molar amount of SiO ₂ provided by said zeolite FAU, AI ₂ O ₃ (fau) being the molar amount of AI ₂ O ₃ provided by said FAU zeolite and Y ₂ O ₃ being the molar amount of Y ₂ O ₃ provided by the additional source of said oxide Y ₂ O ₃ .

Advantageously, in this embodiment, the molar composition of the reaction mixture is:

(XO ₂ + SiO ₂ (fau)) / (AI ₂ O ₃ (fau) + Y2Û ₃ )

H ₂ O / (XO ₂ + SîO ₂ (fau))

R / (XO ₂ + SiO ₂ (fau))

M ₂ / _n O / (XO ₂ + SiO ₂ (fau))

CuO / (XO ₂ + SiO ₂ (fau)) between 2 and 200, preferably between 4 and 100;

between 1 and 100, preferably between 5 and 60;

between 0.01 and 0.6, preferably between 0.05 and 0.5;

between 0.005 and 0.7, preferably between 0.01 and 0.5;

between 0.005 and 0.06, preferably between 0.006 and 0.05;

OCPLX / CuO between 0.8 and 2, preferably between 0.8 and 1.5, preferably between 0.9 and 1.2;

in which XO ₂ is the molar quantity of X0 ₂ supplied by the additional source of said oxide XO ₂ , SIO ₂ (fau) is the molar quantity of SIO ₂ supplied by the zeolite FAU, Y ₂ O ₃ is the molar quantity of Y ₂ O ₃ provided by the additional source of said oxide Y ₂ O ₃ , AI ₂ O _{3 (F} au) the molar amount of AI ₂ O ₃ provided by the zeolite FAU, H ₂ O the molar amount of water present in the reaction mixture , R the molar quantity of said nitrogenous organic compound, M ₂ / _n O the molar quantity of M ₂ / _n O provided by the FAU zeolite and by the source of alkali metal and / or alkaline earth metal, OCPLX the molar quantity d 'organic complexing agent and CuO the molar amount of CuO provided by the copper source.

The possible addition of at least one additional source of an oxide XO ₂ and / or of at least one additional source of an oxide Y ₂ O ₃ makes it possible in particular to adjust the molar ratio of all of the tetravalent elements , expressed in their oxide form, relative to all the trivalent elements, expressed in their oxide form, i.e. the molar ratio (XO ₂ + SIO ₂ (fau)) / (AI ₂ O ₃ (fau) + Y2O ₃ ), of the precursor gel of the zeolitic composite material containing copper and a mixture of AFX and BEA zeolites, obtained at the end of step i) of the process according to the invention.

The additional source (s) of oxide XO ₂ can be any compound comprising the tetravalent element X, X being chosen from the group formed by silicon, germanium and titanium, preferably silicon, and being able to release this element in aqueous solution in reactive form.

When X is titanium, Ti (EtO) 4 is advantageously used as the source of titanium.

In the preferred case where X is silicon, the source of silicon can be any one of said sources commonly used for the synthesis of zeolites, for example powdered silica, silicic acid, colloidal silica, dissolved silica or tetraethoxysilane (TEOS). Among the powdered silicas, it is possible to use precipitated silicas, in particular those obtained by precipitation from an alkali metal silicate solution, fumed silicas, for example CAB-OSIL or Aerosil and silica gels. It is possible to use colloidal silicas having different particle sizes, for example of average equivalent diameter between 10 and 15 nm or between 40 and 50 nm, such as those sold under the registered trademarks such as LUDOX. Preferably, the source of silicon is Aerosil.

The additional source (s) of oxide Y ₂ O ₃ may (may) be any compound comprising the trivalent element Y, Y being chosen from the group formed by aluminum, boron and gallium , preferably aluminum, and capable of releasing this element in aqueous solution in reactive form. Element Y can be incorporated into the mixture in an oxidized form YOb with 1 <b <3 (b being an integer or a rational number) or in any other form.

In the preferred case where Y is aluminum, the aluminum source is preferably amorphous aluminum hydroxide or an aluminum salt, for example chloride, nitrate, or sulfate, sodium aluminate , an aluminum alkoxide, or alumina proper, preferably in hydrated or hydratable form, such as, for example, colloidal alumina, pseudoboehmite, gamma alumina or alpha or beta trihydrate. Mixtures of the sources cited above can also be used.

Step i) of mixing the process according to the invention is carried out until a homogeneous reaction mixture, called gel or precursor gel, is obtained. Preferably, step i) of mixing is carried out for a duration greater than or equal to 10 minutes and advantageously for less than 2 hours, in particular less than 1.5 hours, preferably at room temperature and preferably with stirring. , at low or high shear rate, the stirring system being any system known to those skilled in the art, for example a mechanical paddle stirrer or a turbine.

During this mixing step i), the aqueous solvent introduced can optionally partly evaporate.

Step (i) of the process according to the invention consists in preparing an aqueous reaction mixture comprising at least one zeolite of structural type FAU, optionally an additional source of an oxide XO ₂ and / or an additional source of an oxide

Y2O3, at least one nitrogenous organic compound R chosen from 1.5bis dihydroxide (methylpiperidinium) pentane, 1.6bis dihydroxide (methylpiperidinium) hexane and 1.7bis dihydroxide (methylpiperidinium) heptane, at least one organic complexing agent (OCPLX) chosen from triethylenetetramine (TETA) and tetraethylenepentamine (ΤΕΡΑ), at least one source of copper and at least one source of alkali and / or alkaline earth metal, to obtain the precursor gel of an AFX-BEA composite material containing copper. The amounts of said reagents are adjusted as indicated above so as to give this gel a composition allowing the crystallization of said zeolitic composite material during step ii) of the process according to the invention.

It may be advantageous to add crystalline seeds of a zeolite of structural type AFX, of a zeolite of structural type BEA and / or of a composite material AFX-BEA containing copper, to the reaction mixture during the said step. i) of the process of the invention, in order to reduce the time necessary for the formation of the crystals of the target composite material and / or the total duration of crystallization. Said crystal seeds also promote the formation of said zeolitic AFX-BEA composite material containing copper to the detriment of impurities other than said zeolitic composite material. The crystalline seeds are generally added in a proportion of between 0.01 and 10% by weight relative to the total weight of the sources of said element (s) tetravalent (s) and trivalent (s) in anhydrous form used in the reaction mixture, said seeds lenses not taken into account in the total weight of the sources of the tetravalent and trivalent elements. Said seeds are also not taken into account to determine the molar composition of the reaction mixture and / or the gel, defined further, that is to say in the determination of the different molar ratios of the composition of the reaction mixture.

Advantageously, step i) of the process according to the invention comprises a step of maturing the reaction mixture, implemented before the hydrothermal crystallization. This ripening stage makes it possible to control the size of the crystals of the AFX-BEA composite material containing copper. Said ripening also promotes the formation of said zeolitic composite material to the detriment of impurities. The reaction mixture matures during said step i) of the process of the invention can be carried out at room temperature or at a temperature between 20 and 100 ° C., with or without stirring, for a period advantageously between 30 minutes and 48 hours.

Stage ii) hydrothermal treatment

The preparation process according to the invention comprises a step ii) of hydrothermal treatment of said precursor gel obtained at the end of step i), optionally matured, at a temperature between 120 ° C and 220 ° C, lasting a period between 12 hours and 15 days, until said AFX-BEA composite material containing copper is formed, that is to say until crystallization, preferably complete, of said composite material. According to the invention, this step ii) of hydrothermal treatment can also be called crystallization step, reaction step or even synthesis step.

Crystallization is considered complete as soon as no more presence of amorphous product or FAU zeolite is detected by X-ray analysis of a sample of the reaction medium extracted during the synthesis.

In accordance with step (ii) of the process according to the invention, the temperature to which the precursor gel obtained at the end of step i), optionally matured, is between 120 ° C and 220 ° C , preferably between 50 ° C and 195 ° C, for a period of between 12 hours and 15 days, preferably between 12 hours and 12 days, and more preferably between 12 hours and 8 days. These operating conditions make it possible to obtain crystallization, preferably complete, of the targeted composite material.

Advantageously, the hydrothermal treatment is implemented at the autogenous reaction pressure.

The hydrothermal treatment is generally carried out with stirring or in the absence of stirring, preferably with stirring. Any stirring system known to a person skilled in the art can be used, for example inclined blades with counter blades, stirring turbines, Archimedes screws.

At the end of the reaction, the solid phase formed is advantageously filtered, washed, preferably with preferably deionized water, and then dried. Drying is generally carried out at a temperature between 20 and 150 ° C, preferably between 60 and 100 ° C, for a period of between 24 hours.

The loss on ignition (PAF) of said solid obtained after drying (and before the possible calcination step) is generally between 5 and 15% by weight.

According to the invention, loss of ignition (PAF) is understood to mean the percentage of loss of mass undergone by a solid compound, a mixture of solid compounds or a paste, in particular by the composite material prepared according to the invention, during a heat treatment at 1000 ° C. for 2 hours, in a static oven (muffle type), relative to the mass of the solid compound, of the mixture of solid compounds or of the initial paste, in particular with respect to the mass of the dried composite material tested. The loss on ignition generally corresponds to the loss of solvent (such as water) contained in the solids but also to the elimination of organic compounds contained in the solid mineral constituents.

Advantageously, the solid obtained at the end of step ii) of the process according to the invention, preferably washed and dried, can then be calcined. The calcination step is preferably carried out at a temperature between 450 and 700 ° C for a period between 2 and 20 hours. Calcination may be preceded by a gradual rise in temperature.

The solid obtained at the end of the calcination step is devoid of any organic species and in particular of the organic structuring agent R and the organic complexing agent OCPLX.

The solid obtained at the end of step ii) of the process according to the invention, preferably washed and dried and optionally calcined, is generally analyzed by X-ray diffraction. The X-ray diffraction makes it possible to verify that the solid obtained is indeed the expected zeolitic composite material, composed of a mixture of AFX and BEA zeolites and containing copper. This technique also makes it possible to determine the mass proportion of the mixture of AFX and BEA zeolites in said composite material and the relative proportions of each zeolite, AFX and BEA, contained in said composite material obtained by the process of the invention. Advantageously, the mass proportion of the AFX and BEA zeolites in the composite material obtained is greater than or equal to 90%, preferably greater than or equal to 95%, preferably greater than or equal to 99% and even more preferably greater than or equal to 99 , 8%, relative to the total mass of said composite material, in its anhydrous form. In other words, the zeolitic composite material obtained comprises less than 10% by mass, preferably less than 5% by mass, preferably less than 1% by mass and even more preferably less than 0.2% by mass of impurities and / or of crystalline or amorphous phase other than AFX and BEA (the terminals are not included). Very advantageously, the method of the invention leads to the formation of a composite material containing copper and a mixture of AFX and BEA zeolites, free from any other crystalline or amorphous phase and / or any impurity.

Advantageously, the solid obtained at the end of step ii) of the method according to the invention is an AFX-BEA composite material containing copper and has an X-ray diffraction diagram comprising at least the lines listed in Table 1 .

The X-ray diffraction diagram of the composite material prepared according to the method of the invention is obtained by radiocrystallographic analysis using a diffractometer using the conventional method of powders with the Koci radiation of copper (λ = 1.5406A). From the position of the diffraction peaks represented by the angle 2Θ, we calculate, by the Bragg relation, the reticular equidistances dhki characteristic of the sample. The measurement error A (dhki) on dhki is calculated using the Bragg relation as a function of the absolute error Δ (2Θ) assigned to the measurement of 2Θ. An absolute error Δ (2Θ) equal to ± 0.02 ° is commonly accepted. The relative intensity l _re i assigned to each value of dhki is measured according to the height of the corresponding diffraction peak. The X-ray diffraction diagram of the AFX-BEA composite material containing copper prepared according to the invention comprises at least the lines with the dhki values given in Table 1. In the dhki column, the average values of the inter-reticular distances in Angstroms 5 (Â) are indicated. Each of these values must be assigned the measurement error

A (dhki) between ± 0.6Â and ± 0.01 Â.

Table 1: Average values of the dhki and relative intensities measured on an X-ray diffraction diagram of the zeolitic composite material prepared according to the invention

2 theta (°) dhkl (TO) Irel 2 theta (°) dhkl (Â) Irel 7.49 11.79 ff-f 26,11 3.41 f-m 7.71 11.46 ff-f 26.94 3.31 ff 8.71 10.14 mf-m 27,11 3.29 ff 11,66 7.59 f-mf 27.61 3.23 ff 12.97 6.82 f 28.04 3.18 mf-m 15,00 5.90 ff 28.68 3.11 ff 15.40 5.75 ff 29.51 3.03 ff 15.66 5.66 f-mf 30.19 2.96 ff-f 17.47 5.07 mf 30.58 2.92 mf 17,90 4.95 f-mf 30.99 2.88 ff 19.42 4.57 ff 31.59 2.83 f-mf 19.88 4.46 ff-f 32.50 2.75 ff 20.38 4.36 F-FF 33.73 2.66 f-mf 21.08 4.21 f 34.29 2.61 ff 21.31 4.17 ff-f 34.78 2.58 ff 21.82 4.07 F-FF 35,11 2.55 ff 22,19 4.00 f-m 35.79 2.51 ff 22.34 3.98 f-FF 37.56 2.39 ff 22.54 3.94 ff-f 38,00 2.37 ff 22,70 3.91 ff-f 39.18 2.30 ff 23.67 3.76 mf 39.61 2.30 ff 25.24 3.52 ff

ίο where FF = very strong; F = strong; m = medium; mf = medium weak; f = weak; ff = very weak.

The relative intensity l _re i is given in relation to a relative intensity scale where a value of 100 is assigned to the most intense line of the X-ray diffraction diagram: ff <15; 15 <f <30; 30 <mf <50; 50 <m <65; 65 <F <85;FF>85; 1 <ff-f <30; 30 <mf-m <65; 15 <f-mf <50; 65 <F-FF <100; 15 <fm <65; 15 <fFF <100.

According to the invention, the mass composition of the composite material prepared, in particular the relative mass fractions of zeolites of structural type AFX and of structural type BEA present in said composite material, is advantageously determined using a method similar to the standard ASTM D3906 03, by comparison of the surfaces of the peaks at the angles (2Θ) 20.38 ± 0.1 (hkl: 211); 23.67 ± 0.1 (hkl: 105); 26.1 ± 0.1 (hkl: 303) and 28.02 ± 0.1 (hkl: 106) of the X-ray diagrams obtained for the composite material according to the invention and a zeolite of AFX structural type of reference, of preferably of high purity, that is to say having a purity greater than or equal to 99.8%. The mass ratio of the two zeolites AFX and BEA in the composite material according to the invention is thus evaluated by comparing the sum of the surface of the peaks at the angles (2Θ) mentioned above obtained for the composite material prepared according to the invention with that obtained for a reference sample of AFX zeolite and using the following calculation formula:

AFX / BEA = SAFXc / (SAFXr - SaFXc) where Safxc is the sum of the areas of the peaks present at the angles (2Θ) 20.38 ± 0.1 (hkl: 211); 23.67 ± 0.1 (hkl: 105); 26.1 ± 0.1 (hkl: 303) and 28.02 ± 0.1 (hkl: 106) of the diffractogram of the AFX-BEA composite material containing copper prepared according to the invention and S _AF x _r is the sum of surfaces of the peaks present at the angles (2Θ): 20.38 (hkl: 211); 23.67 (hkl: 105); 26.1 (hkl: 303) and 28.02 (hkl: 106) of the diffractogram of the zeolite of pure AFX structural type, used as a reference. The pure AFX structural type zeolite, used as a reference, can, for example, be prepared according to the process illustrated in Example 5 of the present disclosure.

The presence and the quantification of the copper element in the composite material according to the invention are advantageously determined using the analysis method by X-ray fluorescence spectrometry.

X-ray fluorescence spectrometry (FX) is a chemical analysis technique using a physical property of matter, X-ray fluorescence. It allows the analysis of the majority of chemical elements from Beryllium (Be) in concentration ranges from a few ppm to 100%, with precise and reproducible results. X-rays are used to excite the atoms of the test sample. The atoms then excited emit X-rays at an energy characteristic of each element present. The intensity and energy of these X-rays emitted are then measured to determine the concentration of the elements, in particular Cu and / or Si Al, in the composite material.

The zeolitic composite material obtained by the process according to the invention is advantageously in its protonated form or in its hydrogen form. Said hydrogen form can be obtained by carrying out an ion exchange with an acid, in particular a strong mineral acid such as hydrochloric, sulfuric or nitric acid, or with a compound such as chloride, sulphate or ammonium nitrate . Ion exchange can be accomplished by suspending the AFX-BEA copper-containing composite material one or more times with the ion exchange solution. Said composite material can be calcined before or after ion exchange, or between two ion exchange stages. The composite material is preferably calcined before the ion exchange, in order to remove any organic substance included in the porosity of the zeolitic material, and insofar as the ion exchange is thereby facilitated.

The zeolitic composite material composed of a mixture of AFX and BEA zeolites and containing copper obtained by the process of the invention can be used after ion exchange as an acid solid for catalysis in the fields of refining and petrochemistry. It can also be used as an adsorbent or as a molecular sieve.

FIGURES

FIG. 1 represents the chemical formulas of the specific nitrogenous organic compounds which can be chosen as a structuring agent in the synthesis process according to the invention.

FIG. 2 represents the X-ray diffraction diagram of the composite material according to the invention, composed of a zeolite of structural type AFX and a zeolite of structural type BEA and containing copper, obtained according to Example 3.

FIG. 3 represents a scan with a scanning electron microscope (SEM) of the composite material obtained according to example 3.

ίο FIG. 4 represents the X-ray diffraction diagram of the zeolite of the pure AFX structural type, obtained according to example 5.

The invention is illustrated by the following examples which are in no way limiting in nature.

EXAMPLES

Example 1: preparation of 1,6-bis (methvlpiperidinium) hexane dihydroxide (structuring R).

g of 1,6-dibromohexane (0.20 mole, 99%, Alfa Aesar) are added to a 1 L flask containing 50 g of N-methylpiperidine (0.51 mole, 99%, Alfa Aesar) and 200 mL d ethanol. The reaction medium is stirred and brought to reflux for 5 hours. The mixture is then cooled to room temperature and then filtered. The mixture is poured into 300 ml of cold diethyl ether then the precipitate formed is filtered and washed with 100 ml of diethyl ether. The solid obtained is recrystallized from an ethanol / ether mixture. The solid obtained is dried under vacuum for 12 hours. 71 g of a white solid are obtained (ie a yield of 80%).

The product has the expected ¹ H NMR spectrum and corresponds to the dibromide of 1.6bis (methylpiperidinium) hexane. ¹ H NMR (D ₂ O, ppm / TMS): 1.27 (4H, m); 1.48 (4H, m); 1.61 (4H, m); 1.70 (8H, m); 2.85 (6H, s); 3.16 (12H, m).

18.9 g of Ag ₂ O (0.08 mole, 99%, Aldrich) are added to a 250 mL teflon beaker containing 30 g of 1,6-bis (methylpiperidinium) hexane dibromide (0.07 mole ) prepared and 100 mL deionized water. The reaction medium is stirred protected from light for 12 hours. The mixture is then filtered. The filtrate obtained is composed of an aqueous solution of 1.6 bis dihydroxide (methylpiperidinium) hexane. The assay of this species is carried out by proton NMR using formic acid as a standard. The value obtained is 21.56% by weight of 1,6-bis (methylpiperidinium) hexane dihydroxide.

Example 2: preparation of a material containing copper and a mixture of zeolites of structural type AFX and BEA according to the invention.

0.94 g of sodium hydroxide (98% by weight, Aldrich) is dissolved in 37.42 g of deionized water, with stirring (300 rpm) and at room temperature. 43.04 g of an aqueous solution at 21.56% by weight of 1.6 bis dihydroxide (methylpiperidinium) hexane prepared according to Example 1 are added. The solution is then homogenized with stirring at 300 rpm for 10 minutes. 8.47 g of HY CBV780 zeolite (of molar ratio S1O2 / AI2O3 = 98.24; PAF = 8.52%, from Zeolyst) are then added to the solution with stirring for 5 minutes. 0.88 g of amorphous aluminum hydroxide gel (AI (OH) ₃ amorphous gel, 58.55% AI ₂ O ₃ , Merck), i.e. a molar ratio AI ₂ O ₃ (g _e i amorphous) / Al2O ₃ (FAU) = 3.9, are introduced into the solution obtained, still with stirring. The mixture is then homogenized for 10 minutes at room temperature. To this solution is added with stirring another solution obtained by dissolving 0.52 g of copper sulphate and 0.40 g of tetraethylene pentamine (ΤΕΡΑ) in 10.94 g of deionized water. The whole is kept under stirring for another 10 minutes at room temperature. The reaction mixture has the following molar composition: 100 SiO ₂ : 5 AI ₂ O ₃ : 9.3 Na ₂ O: 16.7 R: 1.65 CuO: 1.65 ΤΕΡΑ: 3673 H ₂ O, i.e. a molar ratio SiO ₂ / AI ₂ O ₃ of 20.

The homogeneous precursor gel then obtained is introduced into a 160 mL stainless steel reactor, equipped with a stirring system comprising four inclined blades and counter blades. The reactor is closed and heated at a temperature of 170 ° C for 48 hours with stirring at 200 rpm. The crystals obtained are separated by filtration and washed with deionized water until a pH of the washing water is lower than 8. The washed material is then dried overnight at 100 ° C. The loss on ignition (PAF) of the dried solid, evaluated at 1000 ° C. for 2 hours, is 12.4%.

The dried solid is then introduced into a muffle furnace where a calcination step is carried out: the calcination cycle includes a rise in temperature from 1.5 ° C / min to 200 ° C, a plateau at 200 ° C may last 2 hours, a temperature rise of 1 ° C / min to 550 ° C followed by a plateau at 550 ° C maintained for 8 hours then a return to room temperature.

The calcined solid product is analyzed by X-ray diffraction and identified as consisting of at least 99% by mass of a mixture of AFX zeolite (55% by mass relative to the material obtained in its anhydrous form) and BEA zeolite (45 % by mass relative to the material obtained in its anhydrous form) with a mass ratio of AFX / BEA = 1.22. The material is also analyzed by X-ray fluorescence (FX): it contains 1.8% by mass of Cu.

Example 3: Preparation of a material containing copper and a mixture of zeolites of structural type AFX and BEA according to the invention

0.95 g of sodium hydroxide (98% by weight, Aldrich) are dissolved in 38.6 g of deionized water, with stirring (300 rpm) and at room temperature. 43.2 g of a 21.56% by weight aqueous solution of 1.6bis dihydroxide (methylpiperidinium) hexane prepared according to Example 1 are added. The solution is then homogenized with stirring at 300 rpm for 10 minutes. 8.50 g of HY CBV780 zeolite (SiO ₂ / AI ₂ O ₃ molar ratio = 98.24; PAF = 8.52%, from Zeolyst) are added to the solution which is then left to stir for 10 minutes. Then 0.88 g of amorphous gel of aluminum hydroxide (AI (OH) ₃ amorphous gel, 58.55% AI ₂ O ₃ , Merck), that is to say a molar ratio AI ₂ O ₃ (g _e i amorphous) / AI ₂ O ₃ (FAU) = 3.9, are introduced into the solution thus obtained, still with stirring. The mixture is then homogenized for 10 minutes at room temperature. Another solution is added to this solution, with stirring, obtained by dissolving 0.26 g of copper sulphate and 0.20 g of tetraethylene pentamine (ΤΕΡΑ) in 10 g of deionized water. The whole is kept under stirring for another 10 minutes at room temperature. The reaction mixture has the following molar composition: 100 SIO ₂ : 5 AI ₂ O ₃ : 9.3 Na ₂ O: 16.7 R: 0.83 CuO: 0.83 ΤΕΡΑ: 3673 H ₂ O, i.e. a molar ratio SiO ₂ / AI ₂ O ₃ of 20.

The homogeneous precursor gel then obtained is introduced into a 160 mL stainless steel reactor, equipped with a stirring system comprising four inclined blades and counter blades. The reactor is closed and heated at a temperature of 170 ° C for 48 hours with stirring at 200 rpm. The crystals obtained are separated by filtration and washed with deionized water until a pH of the washing water is lower than 8. The washed material is then dried overnight at 100 ° C. The loss on ignition (PAF) of the dried solid, evaluated at 1000 ° C. for 2 hours, is 11.5%.

The solid is then introduced into a muffle furnace where a calcination step is carried out: the calcination cycle includes a rise in temperature from 1.5 ° C./min to 200 ° C., a plateau at 200 ° C. may last for 2 hours, a temperature rise of 1 ° C / min to 550 ° C followed by a plateau at 550 ° C maintained for 8 hours and then a return to room temperature.

The calcined solid product is analyzed by X-ray diffraction. The X-ray diagram obtained is presented in FIG. 2. The calcined solid product is identified as consisting of at least 95% by mass of a mixture of AFX zeolite (60 % by mass relative to the material obtained in its anhydrous form) and of BEA zeolite (40% by mass relative to the material obtained in its anhydrous form) with a mass ratio of AFX / BEA = 1.5. The material is also analyzed by X-ray fluorescence (FX): it contains 1.0% by mass of Cu.

The composite material obtained is analyzed by scanning electron microscopy (SEM). Figure 3 shows the SEM image of the composite material obtained.

Example 4: Preparation of a material containing copper and a mixture of zeolites of structural type AFX and BEA according to the invention

0.95 g of sodium hydroxide (98% by weight, Aldrich) are dissolved in 38.41 g of deionized water, with stirring (300 rpm) and at room temperature. 43.08 g of a 21.56% by weight aqueous solution of 1.6bis dihydroxide (methylpiperidinium) hexane prepared according to Example 1 are added. The solution is then homogenized with stirring at 300 rpm for 10 minutes. 8.48 g of HY CBV780 zeolite (of molar ratio S1O2 / AI2O3 = 98.24; PAF = 8.52%, from Zeolyst) are then added to the solution with stirring for 5 minutes. 0.88 g of amorphous gel of aluminum hydroxide (AI (OH) ₃ amorphous gel, 58.55% AI ₂ O ₃ , Merck), i.e. a molar ratio of AI ₂ O ₃ ( _ge i amorphous) / Al2O ₃ (FAU) = 3.9, are introduced into the solution obtained, still with stirring. The mixture is then homogenized for 10 minutes at room temperature. Another solution is added to this solution, with stirring, obtained by dissolving 0.52 g of copper sulphate and 0.31 g of tetraethylenetetramine (TETA) in 10 g of deionized water. The whole is kept under stirring for another 10 minutes at room temperature. The reaction mixture has the following molar composition: 100 S1O2: 5 AI2O3: 9.3 Na ₃ O: 16.7 R: 1.65 CuO: 1.65 TETA: 3673 H ₂ O, i.e. a molar ratio SiO ₂ / AI ₂ O ₃ of 20.

The homogeneous precursor gel then obtained is introduced into a 160 mL stainless steel reactor, equipped with a stirring system comprising four inclined blades and counter blades. The reactor is closed and heated to a temperature of 170 ° C for 36 hours with stirring at 200 rpm. The crystals obtained are separated by filtration and washed with deionized water until a pH of the washing water is lower than 8. The washed material is then dried overnight at 100 ° C. The loss on ignition (PAF) of the dried solid, evaluated at 1000 ° C. for 2 hours, is 11.6%.

The dried solid is then introduced into a muffle furnace where a calcination step is carried out: the calcination cycle includes a rise in temperature from 1.5 ° C / min to 200 ° C, a plateau at 200 ° C may last 2 hours, a temperature rise of 1 ° C / min to 550 ° C followed by a plateau at 550 ° C maintained for 8 hours then a return to room temperature.

The calcined solid product is analyzed by X-ray diffraction and identified as consisting of at least 99% by mass of a mixture of AFX zeolite (69% by mass relative to the material obtained in its anhydrous form) and BEA zeolite (31 % by mass relative to the material obtained in its anhydrous form) with a mass ratio of AFX / BEA = 2.2. Analysis of the mixture by X-ray fluorescence (FX) indicates a value of 2.0% Cu.

Example 5: Preparation of a pure AFX structural type zeolite

0.179 g of a FAU structural type zeolite (CBV600 Zeolyst, SiO ₂ / AI ₂ O ₃ = 5.46, PAF = 12.65%,% in the mixture of FAU zeolites in anhydrous form = 20.64) were mixed with 4.86 g of deionized water. 0.643 g of a FAU structural type zeolite (CBV720 Zeolyst, SiO ₂ / AI ₂ O ₃ = 33.52, PAF = 6.63%,% in the mixture of FAU zeolites = 79.36) are added to the preceding mixture , the preparation obtained is kept under stirring for 10 minutes. 2.891 g of an aqueous solution of 1,6-bis (methylpiperidinium) hexane dihydroxide (20.91% by weight) prepared according to example 1, are added to the preceding mixture, and the preparation is kept under stirring for 10 minutes . Subsequently, 0.428 g of a 20% by weight aqueous solution of solid sodium hydroxide of 98% by weight purity (Aldrich) was incorporated into the synthesis mixture which is stirred for half an hour. The molar composition of the mixture is as follows: 60 SiO ₂ : 3.3 AI ₂ O ₃ : 10 R: 5.6 Na ₂ O: 2204 H ₂ O, i.e. an SiO ₂ / AI ₂ O ₃ ratio of 18. The precursor gel is then transferred, after homogenization in an autoclave. The autoclave is closed and then heated for 6 days at 180 ° C. with stirring at 35 rpm with a spit system. The crystallized product obtained is filtered, washed with deionized water and then dried overnight at 100 ° C. The solid is then introduced into a muffle furnace where a calcination step is carried out: the calcination cycle includes a rise in temperature of 1.5 ° C / min to 200 ° C, a plateau at 200 ° C maintained for 2 hours, a temperature rise of 1 ° C / min to 550 ° C followed by a plateau at 550 ° C maintained for 8 hours, then a return to room temperature.

The calcined solid product was analyzed by X-ray diffraction and identified as consisting of a zeolite of pure AFX structural type, that is to say of purity greater than 99.8% by weight. The diffraction diagram performed on the solid of calcined AFX structural type is given in FIG. 4. The product has a SiO ₂ / AI ₂ O ₃ molar ratio of 12.7 as determined by X-ray fluorescence.

Claims (26)

1. Process for the preparation of a zeolitic composite material composed of a mixture of zeolites of structural type AFX and of structural type BEA and containing copper, said composite material having a zeolitic structure and comprising between 30 and 90% by mass of zeolite of structural type AFX, relative to the total mass of said composite material in its anhydrous form, between 10 and 70% by mass of zeolite of structural type BEA, relative to the total mass of said composite material in its anhydrous form and between 0.05 and 6% by mass of copper element, relative to the total mass of said composite material in its anhydrous form; said method comprising at least the following steps: i) the mixture in aqueous medium, of at least one zeolite of structural type FAU having a molar ratio SiO ₂ (fau / AI ₂ O _{3 (FAU)} of between 2 and 200, of at least one organic nitrogen compound R chosen among 1,5bis dihydroxide (methylpiperidinium) pentane, 1,6bis dihydroxide (methylpiperidinium) hexane, 1,7bis dihydroxide (methylpiperidinium) heptane and their mixtures, of at least one source of at least one alkali metal and / or alkaline earth M of valence η, n being an integer greater than or equal to 1, of at least one organic complexing agent and at least one source of copper, to obtain a precursor gel, the reaction mixture having the composition following molar: (SiO ₂ (fau)) / (AI ₂ O ₃ (fau)) between 2 and 200; H ₂ O / (SiO ₂ (fau)) between 1 and 100; R / (SiO ₂ (fau)) between 0.01 and 0.6; M2 / _n O / (SiO ₂ (FAU)) between 0.005 and 0.7; CuO / (SiO ₂ (fau)) between 0.005 and 0.06; OCPLX / CuO between 0.8 and 2; in which SiO _{2 (F} au) designates the molar amount of SiO ₂ provided by the FAU zeolite, and AI ₂ O _{3 (} fau) designates the molar amount of AI ₂ O ₃ provided by the FAU zeolite, H ₂ O the molar amount of water present in the reaction mixture, R the molar quantity of said nitrogenous organic compound, M _{2 / n} O being the molar quantity of M ₂ / _n O supplied by the FAU zeolite and by the source of alkali metal and / or metal alkaline earth, OCPLX is the molar amount of organic complexing agent and CuO is the molar amount of CuO provided by the copper source; ii) hydrothermal treatment of said gel obtained at the end of step i) at a temperature between 120 ° C and 220 ° C, for a period between 12 hours and 15 days. 2. Method according to the preceding claim wherein the organic nitrogen compound R is 1,6-bis (methylpiperidinium) hexane dihydroxide. 3. Method according to one of the preceding claims wherein the molar ratio R / (SiO ₂ (fau)) is between 0.05 and 0.5. 4. Method according to one of the preceding claims wherein the molar ratio (SiO ₂ (fau)) / (AI ₂ O ₃ (fau)) is between 4 and 100. 5. Method according to one of the preceding claims, in which the H ₂ O / (SIO ₂ (fau)) molar ratio is between 5 and 60. 6. Method according to one of the preceding claims wherein the molar ratio M ₂ / _n O / (SiO ₂ (fau)) is between 0.01 and 0.5. 7. Method according to one of the preceding claims in which M is chosen from lithium, potassium, sodium, magnesium, calcium and the mixture of at least two of these metals, preferably M is sodium. 8. The method of claim 7 wherein the source of at least one alkali and / or alkaline earth metal M is sodium hydroxide. 9. Method according to one of the preceding claims, in which the copper source is chosen from sulphates, nitrates, chlorides, oxalates, organometallic copper complexes or their mixtures, copper sulphates and copper nitrates being preferred. 10. Method according to one of the preceding claims in which the CuO / (SiO ₂ (fau)) molar ratio is between 0.006 and 0.05. 11. Method according to one of the preceding claims, in which the organic complexing agent is triethylenetetramine (TETA) or tetraethylenepentamine (ΤΕΡΑ). 12. Method according to one of the preceding claims, in which the Cu / OCPLX molar ratio is between 0.9 and 1.2. 13. Method according to one of the preceding claims, in which the reaction mixture of step i) comprises at least one additional source of an oxide XO ₂ , X being a tetravalent element chosen from the group formed by silicon, legermanium, titanium, preferably silicon, so that the XO ₂ / SiO ₂ molar ratio (fau) is between 0.001 and 1, preferably between 0.001 and 0.9 and more preferably between 0.001 and 0.01, XO ₂ being the molar amount of XO ₂ provided by the additional source of said oxide XO ₂ , SîO _{2 (F} au) the molar amount of SiO ₂ provided by the zeolite FAU and AI ₂ O _{3 {FA} u) the molar amount of AI ₂ O ₃ provided by the FAU zeolite, the molar composition of the reaction mixture being such that: (XO ₂ + SiO ₂ (fau)) / AI ₂ O ₃ (fau) between 2 and 200, preferably between 4 and 100; H ₂ O / (XO ₂ + SiO ₂ (fau)) between 1 and 100, preferably between 5 and 60; R / (XO ₂ + SiO ₂ (fau)) between 0.01 and 0.6, preferably between 0.05 and 0.5; M2 / nOZ (XC> 2 + S1O2 (fau)) between 0.005 and 0.7, preferably between 0.01 and 0.5; CuO / (XC> 2 + S1O2 (fau)) between 0.005 and 0.06, preferably between 0.006 and 0.05; OCPLX / CuO between 0.8 and 2, preferably between 0.8 and 1.5, preferably between 0.9 and 1.2. 14. Method according to one of claims 1 to 12, wherein the reaction mixture of step i) comprises at least one additional source of an oxide Y2O3, Y being a trivalent element chosen from the group formed by aluminum , boron and gallium, preferably aluminum, so that the Y2O3 / AI2O3 (fau) molar ratio is between 0.001 and 10, preferably between 0.001 and 5, preferably between 0.001 and 4, SiO _{2 (} fau) being the molar amount of SiO ₂ provided by the zeolite FAU and AI2O3 (fau) the molar amount of AI2O3 provided by the zeolite FAU and Y ₂ O ₃ being the molar amount of Y ₂ O ₃ provided by the additional source of said oxide Y2O3, the molar composition of the reaction mixture being such that: S1O2 (FAU) / (Al2O3 (FAU) ⁺ Y2O3) between 2 and 200, preferably between 4 and 100; H2O / (SÎO2 (FAU)) between 1 and 100, preferably between 5 and 60; R / (SiC> 2 (FAU)) between 0.01 and 0.6, preferably between 0.05 and 0.5; 1 ^ 1 ^ 0 / (8102 (FAU)) between 0.005 and 0.7, preferably between 0.01 and 0.5; CuO / (SiO2 (FAU)) between 0.005 and 0.06, preferably between 0.006 and 0.05; OCPLX / CuO between 0.8 and 2, preferably between 0.8 and 1.5 and preferably between 0.9 and 1.2. 15. Method according to one of claims 1 to 12, wherein the reaction mixture of step i) comprises at least one additional source of an oxide XO ₂ , X being a tetravalent element chosen from the group formed by silicon , germanium, titanium, preferably silicon, and at least one additional source of an oxide Y ₂ Os, Y being a trivalent element chosen from the group formed by aluminum, boron and gallium, preferably l aluminum, so that: the reaction mixture of step i) contains between 20 and 95% by mass, preferably between 50 and 95% by mass, preferably between 60 and 90% by mass and even more preferably between 65 and 85% by mass, of zeolite of the type structural FAU with respect to the total mass of trivalent and tetravalent elements, in their oxide form; the molar ratio XO ₂ / SiO _{2 (F} au) in the reaction mixture is between 0.001 and 1, preferably between 0.001 and 0.9 and more preferably between 0.001 and 0.01; the molar ratio Y ₂ Os / AI ₂ O3 _(F au) in the reaction mixture is between 0.001 and 10, preferably between 0.001 and 5, preferably between 0.001 and 4; and the molar ratio (XO ₂ + SiO ₂ (fau)) / (AI ₂ C> 3 _(F au) ⁺ Y2O3) in the reaction mixture is between 2 and 200, preferably between 4 and 100, XO ₂ being the molar amount of XO ₂ provided by the additional source of said oxide XO ₂ , SiO _{2 (F} au) being the molar amount of SiO ₂ provided by said starting FAU zeolite, AI ₂ O ₃ ( _F au) being the molar amount of AI ₂ O ₃ provided by said FAU zeolite and Y ₂ O ₃ being the molar amount of Y ₂ O ₃ provided by the additional source of said oxide Y ₂ Os, the molar composition of the reaction mixture being as follows: (XO ₂ + SiO ₂ (fau)) / (AI ₂ O ₃ (fau) + Y2O3) between 2 and 200, preferably between 4 and 100; H ₂ O / (XO ₂ + S1O2 (FAU)) between 1 and 100, preferably between 5 and 60; R / (XO ₂ + SiO ₂ (fau)) between 0.01 and 0.6, preferably between 0.05 and 0.5; M ₂ / _n O / (XO ₂ + SÎO ₂ (FAU)) between 0.005 and 0.7, preferably between 0.01 and 0.5; CuO / (XO ₂ + S1O2 (FAU)) between 0.005 and 0.06, preferably between 0.006 and 0.05; OCPLX / CuO between 0.8 and 2, preferably between 0.8 and 1.5, preferably between 0.9 and 1.2. 16. Method according to one of the preceding claims wherein step i) of mixing is carried out for a duration greater than or equal to 10 minutes and for less than 2 hours, in particular less than 1.5 hours, preferably at room temperature and preferably with stirring, at low or high shear rate 17. Method according to one of the preceding claims in which crystalline seeds of a zeolite of AFX structural type, of a zeolite of BEA structural type and / or of a zeolitic composite material are added to the reaction mixture of step i), preferably in an amount of between 0.01 and 10% by weight relative to the total weight of the sources of silicon and aluminum in anhydrous form present in the mixture, said crystalline seeds not being taken into account in the weight total sources of tetravalent and trivalent elements. 18. Method according to one of the preceding claims wherein step i) comprises a step of maturing the reaction mixture at room temperature or at a temperature between 20 and 100 ° C, with or without stirring, for a period between 30 minutes and 48 hours. 19. Method according to one of the preceding claims wherein the hydrothermal treatment of step ii) is carried out at a temperature between 120 ° C and 220 ° C, preferably between 150 ° C and 195 ° C, for a period of time between 12 hours and 15 days, preferably between 12 hours and 12 days, and more preferably between 12 hours and 8 days, and preferably under autogenous pressure. 20. Method according to one of the preceding claims in which the composite material obtained is filtered, washed and then dried at a temperature between 20 and 150 ° C, preferably between 60 and 100 ° C, for a period between 5 and 24 hours. 21. The method of claim 20 wherein the dried composite material is calcined at a temperature between 450 and 700 ° C for a period between 2 and 20 hours, the calcination may be preceded by a gradual rise in temperature. 22. Zeolite composite material composed of a mixture of zeolites of structural type AFX and of structural type BEA and containing copper, said composite material having a zeolitic structure comprising: - between 30 and 90% by mass of zeolite of AFX structural type, relative to the total mass of said composite material in its anhydrous form; - between 10 and 70% by mass of zeolite of structural type BEA, relative to the total mass of said composite material in its anhydrous form; said composite material comprising between 0.05 and 6% by mass of copper element, relative to the total mass of said composite material in its anhydrous form. 23. Composite material according to the preceding claim having a mass ratio (AFX / BEA) of the AFX zeolite relative to the BEA zeolite, present in said composite material, of between 0.4 and 9, preferably between 0.5 and 7, 5 and more preferably still between 1 and 4. 24. Composite material according to one of claims 22 and 23 having a SiO ₂ / AI ₂ O ₃ molar ratio of between 2 and 100, preferably between 4 and 90 and more preferably between 6 and 80. 25. Material according to one of claims 22 to 23, obtained by the preparation process according to one of claims 1 to 21. 26. Material according to one of claims 22 to 25 having an X-ray diffraction diagram comprising at least the lines having the average values of the dhki and the following relative intensities: 2 theta (°) dhkl (A) Irel 2 theta (°) dhkl (A) Irel 7.49 11.79 ff-f 26,11 3.41 f-m 7.71 11.46 ff-f 26.94 3.31 ff 8.71 10.14 mf-m 27,11 3.29 ff 11,66 7.59 f-mf 27.61 3.23 ff 12.97 6.82 f 28.04 3.18 mf-m 15,00 5.90 ff 28.68 3.11 ff 15.40 5.75 ff 29.51 3.03 ff 15.66 5.66 f-mf 30.19 2.96 ff-f 17.47 5.07 mf 30.58 2.92 mf 17,90 4.95 f-mf 30.99 2.88 ff 19.42 4.57 ff 31.59 2.83 f-mf 19.88 4.46 ff-f 32.50 2.75 ff 20.38 4.36 F-FF 33.73 2.66 f-mf 21.08 4.21 f 34.29 2.61 ff 21.31 4.17 ff-f 34.78 2.58 ff 21.82 4.07 F-FF 35,11 2.55 ff 22,19 4.00 f-m 35.79 2.51 ff 22.34 3.98 f-FF 37.56 2.39 ff 22.54 3.94 ff-f 38,00 2.37 ff 22,70 3.91 ff-f 39.18 2.30 ff 23.67 3.76 mf 39.61 2.30 ff 25.24 3.52 ff where FF = very strong; F = strong; m = medium; mf = medium weak; f = weak; ff = very weak, ίο The relative intensity l _re i is given in relation to a relative intensity scale where a value of 100 is assigned to the most intense line of the X-ray diffraction diagram: ff <15; 15 <f <30; 30 <mf <50; 50 <m <65; 65 <F <85;FF>85; 1 <ff-f <30; 30 <mf-m <65; 15 <f-mf <50; 65 <F-FF <100; 15 <fm <65; 15 <fFF <100.