Synthesis of an IZM-2 zeolite in the presence of ethanol

Abstract

The present invention relates to a novel method for preparing a microporous crystalline solid, referred to as an IZM-2 microporous solid or IZM-2 zeolite. This novel method allows for the synthesis of an IZM-2 zeolite from at least one silicon source, at least one aluminium source, at least one source of an alkali and / or alkaline-earth metal having a valency n, in the absence of an organic structure-directing agent and in the presence of at least one alcohol, preferably ethanol, and seeds of calcined IZM-2 zeolite.

Description

[0001] SYNTHESIS OF AN IZM-2 ZEOLITE IN THE PRESENCE OF ETHANOL

[0002] TECHNICAL FIELD

[0003] The present invention relates to a new process for preparing a microporous crystalline solid, called IZM-2 microporous solid or IZM-2 zeolite. This new process makes it possible to carry out the synthesis of an IZM-2 zeolite from at least one source of silicon, at least one source of aluminum, at least one source of an alkali and / or alkaline-earth metal of valence n, in the absence of organic structuring agent and in the presence of at least one alcohol and preferably ethanol and calcined IZM-2 zeolite seeds. In particular, said new process makes it possible to carry out the synthesis of an IZM-2 zeolite without structuring agent, using calcined IZM-2 zeolite seeds to promote the crystallization of the zeolite and alcohol and preferably ethanol to fill the pores of the zeolite. Said IZM-2 zeolite obtained according to the process of the invention advantageously finds its application as a catalyst, adsorbent or separation agent.

[0004] PREVIOUS ART

[0005] Crystallized microporous materials, such as zeolites or silicoaluminophosphates, are solids widely used in the petroleum industry as catalysts, catalyst supports, adsorbents, or separation agents. Although many microporous crystalline structures have been discovered, the refining and petrochemical industries are always looking for new zeolite structures that exhibit specific properties for applications such as gas purification or separation, carbon species conversion, or others.

[0006] IZM-2 zeolite is a solid with an unknown structure. Model reactions were used (isomerization and disproportionation of meta-xylenes and isomerization-hydrocracking of n-decane) with the objective of predicting the topology of the microporous material IZM-2 (Fecant et al. in J.Catal., 20, (2013) 20-29). The results obtained for these reactions suggest that the structure of the IZM-2 material consists of two types of pore size (10-MR and 12-MR).

[0007] The IZM-2 zeolite has been synthesized in its aluminosilicate form (Fecant et al. FR2918050 A1) and in its purely silicic form (Fecant et al. FR2918050 A1 and Li et al. in Microporous Mesoporous Mater., 237 (2017) 222-227), using the quaternary ammonium ion 1,6-bis(methylpiperidinium)hexane as a structuring agent, in its hydroxide or bromide form. In these documents, the synthesis consists of carrying out a hydrothermal treatment of an aqueous gel containing a source of silicon, a structuring agent (1,6-bis(methylpiperidinium)hexane), optionally a source of amorphous aluminum, and optionally a source of an alkali and / or alkaline earth metal (NaOH).

[0008] Recent work has made it possible to obtain the desired zeolite in the absence of an organic structuring agent and by using zeolite seeds. In this case, aluminum-rich zeolites are generally obtained. (Tatsumi et al. Angew. Chem. Int. Ed. 2009, 48, 9884-9887; T. Okubo et al. J. Am. Chem. Soc. 2012, 134, 11542-11549). It has recently been reported that pure silica zeolites can also be obtained in the absence of a structuring agent. Quinming Wu et al ( ANgew. Chem. Int. Ed. 2019, 58, 12138-12142) propose that the absence of organic molecule and the use of zeolite seeds and ethanol as pore-filling agent allow the preparation of pure silica zeolites. To confirm this, a theoretical simulation by choosing pure silica ZSM-5 as zeolite and ethanol as pore-filling agent is studied. More recently, Yuhan Yanhg et al. (Dalton Trans.2022, 51, 12021) studied the preparation of pure silica zeolites with six-membered rings (SOD, MTN and non-SOD) using zeolite seeds and ethanol in the absence of organic structuring agent.

[0009] The present invention relates to a new process for preparing a microporous IZM-2 solid or an IZM-2 zeolite in the absence of an organic structuring agent which consists of mixing, using a stirrer, a source of silicon, a source of aluminum, a source of alkali and / or alkaline-earth metal M, in the presence of at least one alcohol and preferably ethanol and calcined IZM-2 zeolite seeds. This reaction mixture is then transferred into an autoclave at a temperature of 120 to 220°C for a crystallization time of between 1 and 10 days.

[0010] SUMMARY OF THE INVENTION

[0011] The present invention relates to a new process for preparing a microporous IZM-2 solid or an IZM-2 zeolite which consists of mixing, using a stirrer, a source of silicon, a source of aluminum, an alkaline source, in the presence of ethanol and calcined IZM-2 zeolite seeds.

[0012] An advantage of the present invention is therefore to provide a new preparation process allowing the preparation of an IZM-2 zeolite in the absence of organic structuring agent, in the presence of at least one alcohol and preferably ethanol and calcined IZM-2 zeolite seeds, the process being carried out under specific operating conditions.

[0013] An advantage of the present invention is to provide a new preparation process allowing the formation of a pure IZM-2 zeolite. Any other crystalline or amorphous phase is generally and very preferably absent from the crystalline solid consisting of the IZM-2 zeolite obtained at the end of the preparation process.

[0014] Another advantage of the present invention is to allow the preparation of an IZM-2 zeolite having a SiO2 / AI2O3 ratio of between 70 and 350 and preferably between 90 and 300 and more preferably between 100 and 260.

[0015] LIST OF FIGURES

[0016] Figure 1 shows the X-ray diffraction patterns of IZM-2 zeolite obtained according to Example 4.

[0017] Figure 2 shows the X-ray diffraction patterns of comparative example 11.

[0018] Detailed description of the invention

[0019] The present invention more specifically relates to a new process for preparing a microporous IZM-2 solid or a structuring-free IZM-2 zeolite comprising at least the following steps: i) mixing, in the presence of at least one alcohol and water, at least one source of at least one tetravalent element X in oxide form XO2, at least one source of at least one trivalent element in oxide form Y2O3, at least one source of at least one alkali and / or alkaline-earth metal M of valence n, n being an integer greater than or equal to 1, and calcined IZM-2 zeolite seeds, the mixture having the following molar composition: XO2 / Y2O3 between 70 and 350, H2O / XO2 between 1 and 5, Alcohol / XO2 between 0.05 and 30, M2 / nO / XO2 between 0.05 and 0.45, in which Y is one or more trivalent element(s) chosen from the group formed by the following elements: aluminum, iron, boron, gallium

[0020] X is one or more tetravalent element(s) chosen from the group formed by the following elements: silicon, germanium, titanium,

[0021] M is one or more alkali and / or alkaline earth metal(s) chosen from lithium, sodium, potassium, calcium, magnesium and the mixture of at least two of these metals, the alcohol is chosen from the group formed by primary, secondary and tertiary alcohols, until a homogeneous mixture called precursor gel is obtained; ii) the hydrothermal treatment of said precursor gel obtained at the end of step i) at a temperature between 120 and 220°C, for a period between 1 day and 10 days until said IZM-2 zeolite is formed.

[0022] According to the invention, at least one source of at least one tetravalent element X in oxide form XO2 is incorporated into the mixture for the implementation of step (i) of the preparation process, X being one or more tetravalent element(s) chosen from the group formed by the following elements: silicon, germanium, titanium and preferably X being silicon.

[0023] When X is silicon, the source(s) of said tetravalent element(s) may be any compound comprising element X and capable of releasing this element in aqueous solution in reactive form.

[0024] The silicon source may be any of said sources commonly used for the synthesis of zeolites, preferably chosen from powdered silicas, silicic acid, colloidal silicas, dissolved silica and silicon alkoxides such as tetraethyl orthosilicate (TEOS), alone or as a mixture. Among the powdered silicas, precipitated silicas may be used, in particular those obtained by precipitation from an alkali metal silicate solution, pyrogenic silicas, for example "CAB-O-SIL" and silica gels. Colloidal silicas having different particle sizes, preferably with an average equivalent diameter of between 10 and 15 nm or between 40 and 50 nm, such as those marketed under registered trademarks such as "LUDOX" may advantageously be used.

[0025] Preferably, the silicon source is tetraethyl orthosilicate or TEOS.

[0026] In accordance with the invention, at least one source of at least one trivalent element in oxide form Y2O3 is incorporated into the mixture for the implementation of said step (i) of the preparation process according to the invention, Y being one or more trivalent element(s) chosen from the group formed by the following elements: aluminum, iron, boron, indium and gallium, and at least one of the trivalent elements Y being aluminum.

[0027] The source of aluminum in oxide form AI2O3 is preferably chosen from aluminum hydroxide, aluminum salts, aluminum alkoxides, and alumina itself, preferably in hydrated or hydratable form, preferably chosen from colloidal alumina, pseudoboehmite, gamma alumina or alpha or beta trihydrate. Mixtures of the sources mentioned above can also be used.

[0028] Preferably, the source of aluminum in oxide form AI2O3 is an aluminum salt chosen from aluminum chlorides, aluminum nitrates, aluminum sulfates, sodium aluminates, alone or as a mixture.

[0029] Most preferably, the source of aluminum in oxide form AI2O3 is sodium aluminate.

[0030] According to the invention, at least one source of at least one alkali and / or alkaline-earth metal M of valence n is used in the reaction mixture of step i), n being an integer greater than or equal to 1, M preferably being chosen from lithium, potassium, sodium, magnesium and calcium and the mixture of at least two of these metals. Very preferably, M is sodium.

[0031] Preferably, the source of at least one alkali and / or alkaline earth metal M is sodium hydroxide. According to the invention, seeds of a calcined IZM-2 zeolite are added to the reaction mixture during said step i), in order to reduce the time required for the formation of crystals of an IZM-2 zeolite and / or the total crystallization time. Said crystal seeds also promote the formation of said IZM-2 zeolite to the detriment of impurities. Such seeds comprise crystallized solids, in particular crystals of a calcined IZM-2 zeolite.

[0032] The calcined IZM-2 zeolite seeds are advantageously added to the mixture of step i) in a proportion of between 0.01 and 13%, preferably between 0.01 and 10% and more preferably between 0.01 and 5% of the total mass of the sources of said tetravalent element(s) in their oxide form (SiC) used in the reaction mixture, said seeds not being taken into account in the total mass of the sources of the tetravalent elements. Said seeds are not taken into account in determining the composition of the reaction mixture and / or the gel, defined further, i.e. in determining the different molar ratios, in particular XO2 / Y2O3, F / XiC, alcohol / XO2, M2 / nO / XO2, of the composition of the reaction mixture.

[0033] It is important that the IZM-2 zeolite seeds added to the mixture of step i) are calcined so that the added IZM-2 zeolite seeds no longer include any organic structuring agent in the porosity of said IZM-2 zeolite.

[0034] According to the invention, at least one alcohol is added to the mixture of step i). The alcohol is at least one alcohol chosen from the group formed by primary, secondary and tertiary alcohols, preferably from primary alcohols and preferably, the alcohol is ethanol.

[0035] Step (i) of the process according to the invention consists in preparing a reaction mixture in the presence of at least one alcohol and water, at least one source of a tetravalent element X in oxide form XO2, at least one source of a trivalent element Y in oxide form Y2O3, in the presence of at least one source of one or more alkali and / or alkaline-earth metal(s) M and calcined IZM-2 zeolite seeds, to obtain a precursor gel of an IZM-2 zeolite. The quantities of said reagents in the reaction mixture are adjusted so as to give this gel a composition allowing the crystallization of an IZM-2 zeolite. In accordance with the invention, the mixture of step i) has the following molar composition:

[0036] XO2 / Y2O3 between 70 and 350, preferably between 95 and 300, and more preferably between 100 and 260

[0037] H2O / XO2 between 1 and 5, preferably between 1 and 3 Alcohol / XO2 between 0.05 and 30, preferably between 0.065 and 20 M2 / nO / XO2 between 0.05 and 0.45, preferably between 0.09 and 0.3

[0038] Step i) of mixing is carried out until a homogeneous mixture is obtained, preferably for a period of between 5 and 15 minutes, preferably with stirring by any system known to those skilled in the art with low or high shear rate.

[0039] At the end of step i), a homogeneous precursor gel is obtained.

[0040] Advantageously, the precursor gel obtained at the end of step i) has a molar ratio of the total quantity expressed in oxides of tetravalent elements to the total quantity expressed in oxides of trivalent elements of between 70 and 350. In the case where X=Si and Y=AI, the precursor gel obtained at the end of step i) has a molar ratio SiC / ALOs of between 75 and 350.

[0041] In accordance with step (ii) of the process according to the invention, the precursor gel obtained at the end of step i) is subjected to a hydrothermal treatment carried out at a temperature of between 120 and 220°C for a period of between 1 day and 10 days, until said IZM-2 zeolite is formed.

[0042] The precursor gel is advantageously subjected to treatment under autogenous reaction pressure, optionally by adding gas, for example nitrogen, at a temperature preferably between 150 and 195°C, until complete crystallization of an IZM-2 zeolite.

[0043] Preferably, the time required to obtain crystallization varies between 1 day and 7 days, and more preferably between 2 days and 5 days. Step (ii) is generally carried out with stirring or in the absence of stirring, preferably with stirring. Any stirring system known to those skilled in the art may be used, preferably inclined blades with counterblades, stirring turbines, or Archimedes screws.

[0044] At the end of the reaction, after carrying out said step ii) of the preparation process according to the invention, the solid phase formed from an IZM-2 zeolite is preferably filtered, washed and then dried.

[0045] Drying is preferably carried out at a temperature between 20 and 120°C, preferably between 25 and 100°C, for a period of between 1 and 24 hours. Preferably, said optionally dried IZM-2 zeolite does not undergo a calcination step.

[0046] Uncalcined IZM-2 zeolite is generally analyzed by X-ray diffraction, this technique also making it possible to determine the purity of said zeolite obtained by the process of the invention.

[0047] Very advantageously, the process of the invention leads to the formation of an IZM-2 zeolite, free from any other crystallized or amorphous phase. Said IZM-2 zeolite after the drying step, is then ready for subsequent steps such as ion exchange. For these steps, all conventional methods known to those skilled in the art can be used.

[0048] At the end of said drying step, X-ray diffraction makes it possible to verify that the solid obtained by the process according to the invention is indeed an IZM-2 zeolite. The purity of the IZM-2 zeolite obtained is thus greater than or equal to 90% by weight, preferably greater than or equal to 95% by weight, very preferably greater than or equal to 97%, more preferably greater than or equal to 98%, and even more preferably greater than or equal to 99%, or even greater than or equal to 99.8% by weight relative to the total mass of crystallized solid material obtained.

[0049] The solid obtained has the X-ray diffraction pattern including at least the lines listed in Table 1. Preferably, the X-ray diffraction pattern does not contain any other lines of significant intensity (i.e., of intensity greater than about three times the background noise) than those listed in Table 1. This diffraction pattern is obtained by radiocrystallographic analysis using a diffractometer using the classical powder method with the Kai radiation of copper (X = 1.5406A). From the position of the diffraction peaks represented by the angle 20, the characteristic reticular equidistances dhki of the sample are calculated using the Bragg relation. The measurement error A(dhki) on dhki is calculated using the Bragg relation as a function of the absolute error A(20) assigned to the measurement of 20. An absolute error A(20) equal to ± 0.02° is commonly accepted.The relative intensity Irei assigned to each dhki value is measured from the height of the corresponding diffraction peak. The X-ray diffraction pattern of the crystalline solid IZM-2 according to the invention comprises at least the lines with the dhki values ​​given in Table 1, which shows the average values ​​of the dhki and relative intensities measured on an X-ray diffraction pattern of the uncalcined crystalline solid IZM-2. In the dhki column, the average values ​​of the inter-reticular distances in Angstroms (A) are indicated. Each of these values ​​must be assigned the measurement error A(dhki) between ± 0.6A and ± 0.01A. ff <15 ; 15 <f <30 ; 30 < mf <50 ; 50 <m < 65 ; 65 <F < 85 ; FF >85.

[0050] Table 1 where FF = very strong; F = strong; m = medium; mf = medium weak; f = weak; ff = very weak. The relative intensity Irei is given in relation to a relative intensity scale where a value of 100 is assigned to the most intense line in the X-ray diffraction pattern: ff <15; 15 <f <30 ; 30 < mf <50 ; 50 <m < 65 ; 65 <F < 85 ; FF >85.

[0051] It is also advantageous to obtain the protonated form of the IZM-2 zeolite obtained by the process according to the invention. Said protonated 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 ammonium chloride, sulfate or nitrate. The ion exchange can be carried out by suspending said IZM-2 zeolite in one or more times with the ion exchange solution. Said zeolite can be calcined after the ion exchange, or between two ion exchange steps.

[0052] The IZM-2 zeolite obtained by the process of the invention can be used after ion exchange as an acidic solid for catalysis in the fields of refining and petrochemistry. It can also be used as an adsorbent or as a molecular sieve.

[0053] The process according to the invention makes it possible to obtain an IZM-2 zeolite in the absence of an organic structuring agent by using seeds of IZM-2 zeolite calcined in a reaction mixture comprising at least one alcohol and preferably ethanol and water, having a SiO2 / AI2O3 ratio of between 70 and 350, preferably between 90 and 300 and more preferably between 100 and 260 in the case where X = Si, and Y=AI.

[0054] EXAMPLES

[0055] Comparative Example 1: Preparation of an IZM-2 zeolite in the presence of organic structuring agent 1,6-bis(methylpiperidinium)hexane dibromide (R(Br)2) 49.45 g of an aqueous solution of 1,6-bis(methylpiperidinium)hexane dibromide (20.01% by weight) were mixed with 28.66 g of deionized water and kept stirring for 10 minutes. 1.63 g of sodium hydroxide (99.5% by weight, Aldrich) were added to the previous mixture, the preparation obtained was kept stirring for 15 minutes. 0.108 g of sodium aluminate (53% by weight, Carlo Erba) were added to the previous mixture, and the preparation obtained was kept stirring for 15 minutes.Subsequently, 20.15 g of colloidal silica (Ludox HS40, 40% by weight, Aldrich) were incorporated into the synthesis mixture, and it was kept stirring for the time necessary to evaporate the solvent until the desired gel concentration was obtained, i.e., a molar composition of the mixture as follows: 1 SiC: 0.004 AI2O3: 0.167 R(Br)2: 0.167 Na2O: 33.33 H2O, i.e., a SiC / ALOs ratio of 120. The mixture was stirred vigorously for half an hour. The mixture was then transferred, after homogenization, into a 160 mL stainless steel reactor equipped with a four-blade inclined stirring system. The reactor was closed and then heated for 7 days at 170°C with stirring at 250 - 300 rpm. The crystallized product obtained is filtered, washed with deionized water (to reach a neutral pH) then dried overnight at 100°C.The solid is then introduced into a muffle furnace where calcination is carried out: the calcination cycle includes a temperature rise to 200°C, a hold at 200°C maintained for 2 hours, a temperature rise to 550°C followed by a hold at 550°C maintained for 8 hours and then a return to room temperature.

[0056] The calcined solid product was analyzed by X-ray diffraction and identified as IZM-2 solid.

[0057] Example 2: preparation of an IZM-2 zeolite according to the invention

[0058] 0.17 g of deionized water was mixed with 0.237 g of sodium hydroxide (99.5% by weight, Aldrich). 0.015 g of sodium aluminate (53% by weight, Carlo Erba) was added to the previous mixture, the resulting preparation was kept stirring for 15 minutes. 5.22 g of ethanol (98% by weight, Fisher) was added to the synthesis mixture and kept stirring for 10 minutes. Subsequently, 4.395 g of silicon alkoxide (TEOS, 25% by weight, Fluka) was incorporated into the synthesis mixture and kept stirring for 5 minutes. In order to promote the formation of the crystalline solid IZM-2, 0.109 g of IZM-2 zeolite seeds (10% of the total mass of tetravalent elements in SiC form) prepared according to example 1 are added to the synthesis mixture, which is kept stirring for 10 minutes. The precursor gel obtained has the following molar composition: 1 SiC: 0.004 AI2O3: 10 EtOH: 0.17 Na2O: 1 H2O, i.e. a SiC / ALOs ratio of 250.The mixture is then transferred, after homogenization, into an autoclave. The autoclave is closed and then heated for 5 days at 170°C with stirring at 35 rpm using a rotating spit system. The resulting crystallized product is filtered, washed with deionized water and then dried overnight at 100°C.

[0059] The solid product was analyzed by X-ray diffraction and identified as consisting of an IZM-2 zeolite.

[0060] Example 3: preparation of an IZM-2 zeolite according to the invention

[0061] 0.486 g of deionized water was mixed with 0.704 g of sodium hydroxide (99.5% by weight, Aldrich). 0.029 g of sodium aluminate (53% by weight, Carlo Erba) was added to the previous mixture, the resulting preparation was kept stirring for 15 minutes. 0.15 g of ethanol (98% by weight, Fisher) was added to the synthesis mixture and kept stirring for 10 minutes. Subsequently, 8.663 g of silicon alkoxide (TEOS, 25% by weight, Fluka) was incorporated into the synthesis mixture and kept stirring for 5 minutes. In order to promote the formation of the crystalline solid IZM-2, 0.217 g of IZM-2 zeolite seeds (10% of the total mass of tetravalent elements in SiO2 form) prepared according to Example 1 are added to the synthesis mixture, which is kept stirring for 10 minutes. The precursor gel obtained has the following molar composition: 1 SiC: 0.004 AI2O3: 0.09 EtOH: 0.25 Na2O: 1 H2O, i.e. a SiC / ALOs ratio of 250.The mixture is then transferred, after homogenization, into an autoclave. The autoclave is closed and then heated for 5 days at 170°C with stirring at 35 rpm using a rotating spit system. The resulting crystallized product is filtered, washed with deionized water and then dried overnight at 100°C.

[0062] The solid product was analyzed by X-ray diffraction and identified as consisting of an IZM-2 zeolite.

[0063] Example 4: preparation of an IZM-2 zeolite according to the invention

[0064] 4.84 g of deionized water were mixed with 7.204 g of sodium hydroxide (99.5% by weight, Aldrich). 0.28 g of sodium aluminate (53% by weight, Carlo Erba) were added to the previous mixture, the resulting preparation was kept stirring for 15 minutes. 1.39 g of ethanol (98% by weight, Fisher) were added to the synthesis mixture and kept stirring for 10 minutes. Subsequently, 86.49 g of silicon alkoxide (TEOS, 25% by weight, Fluka) were incorporated into the synthesis mixture and kept stirring for 5 minutes. In order to promote the formation of the crystalline solid IZM-2, 2.17 g of IZM-2 zeolite seeds (10% of the total mass of tetravalent elements in SiC form) prepared according to example 1 are added to the synthesis mixture, which is kept stirring for 10 minutes. The precursor gel obtained has the following molar composition: 1 SiC: 0.004 AI2O3: 0.08 EtOH: 0.26 Na2O: 1 H2O, i.e. a SiC / ALOs ratio of 250.The mixture is then transferred, after homogenization, into an autoclave. The precursor gel is then transferred, after homogenization, into a 160 mL stainless steel reactor equipped with a four-blade inclined stirring system. The reactor is closed and then heated for 7 days at 170°C with stirring at 250-300 rpm. The crystallized product obtained is filtered, washed with deionized water and then dried overnight at 100°C.

[0065] The solid product was analyzed by X-ray diffraction and identified as consisting of an IZM-2 zeolite.

[0066] Example 5: preparation of an IZM-2 zeolite according to the invention

[0067] 1.7 g of deionized water was mixed with 2.479 g of sodium hydroxide (99.5% by weight, Aldrich). 0.144 g of sodium aluminate (53% by weight, Carlo Erba) was added to the previous mixture, the resulting preparation was stirred for 15 minutes. 52.034 g of ethanol (98% by weight, Fisher) was added to the synthesis mixture and stirred for 10 minutes. Subsequently, 43.82 g of silicon alkoxide (TEOS, 25% by weight, Fluka) was incorporated into the synthesis mixture and stirred for 5 minutes. In order to promote the formation of the crystalline solid IZM-2, 1.10 g of IZM-2 zeolite seeds (10% of the total mass of tetravalent elements in SiO2 form) prepared according to example 1 are added to the synthesis mixture, which is kept stirring for 10 minutes. The precursor gel obtained has the following molar composition: 1 SiC: 0.004 AI2O3: 6.08 EtOH: 0.18 Na2O: 1 H2O, i.e. a SiO2 / Al2O3 ratio of 250.The mixture is then transferred, after homogenization, into an autoclave. The precursor gel is then transferred, after homogenization, into a 160 mL stainless steel reactor equipped with a four-blade inclined stirring system. The reactor is closed and then heated for 7 days at 170°C with stirring at 250-300 rpm. The crystallized product obtained is filtered, washed with deionized water and then dried overnight at 100°C. The solid product was analyzed by X-ray diffraction and identified as consisting of an IZM-2 zeolite.

[0068] Example 6: preparation of an IZM-2 zeolite according to the invention

[0069] 1.7 g of deionized water was mixed with 2.482 g of sodium hydroxide (99.5% by weight, Aldrich). 0.142 g of sodium aluminate (53% by weight, Carlo Erba) was added to the previous mixture, the resulting preparation was kept stirring for 15 minutes. 52.05 g of ethanol (98% by weight, Fisher) was added to the synthesis mixture and kept stirring for 10 minutes. Subsequently, 43.82 g of silicon alkoxide (TEOS, 25% by weight, Fluka) was incorporated into the synthesis mixture and kept stirring for 5 minutes. In order to promote the formation of the crystalline solid IZM-2, 1.10 g of IZM-2 zeolite seeds (10% of the total mass of tetravalent elements in SiO2 form) prepared according to example 1 are added to the synthesis mixture, which is kept stirring for 10 minutes. The precursor gel obtained has the following molar composition: 1 SiC: 0.004 AI2O3: 6.08 EtOH: 0.18 Na2O: 1 H2O, i.e. a SiC / ALOs ratio of 250.The mixture is then transferred, after homogenization, into an autoclave. The precursor gel is then transferred, after homogenization, into a 160 mL stainless steel reactor equipped with a four-blade inclined stirring system. The reactor is closed and then heated for 5 days at 190°C with stirring at 250-300 rpm. The crystallized product obtained is filtered, washed with deionized water and then dried overnight at 100°C. The solid product was analyzed by X-ray diffraction and identified as consisting of an IZM-2 zeolite.

[0070] Example 7: Preparation of an IZM-2 zeolite according to the invention 4.83 g of deionized water were mixed with 7.2 g of sodium hydroxide (99.5% by weight, Aldrich). 0.28 g of sodium aluminate (53% by weight, Carlo Erba) were added to the previous mixture, the preparation obtained was kept stirring for 15 minutes. 1.39 g of ethanol (98% by weight, Fisher) were added to the synthesis mixture and kept stirring for 10 minutes. Subsequently, 86.46 g of silicon alkoxide (TEOS, 25% by weight, Fluka) were incorporated into the synthesis mixture and kept stirring for 5 minutes. In order to promote the formation of the crystalline solid IZM-2, 1.089 g of IZM-2 zeolite seeds (5% of the total mass of tetravalent elements in SiO2 form) prepared according to example 1 are added to the synthesis mixture, which is kept stirring for 10 minutes.The precursor gel obtained has the following molar composition: 1 SiC: 0.004 AI2O3: 0.08 EtOH: 0.26 Na2O: 1 H2O, i.e. a SiC / ALOs ratio of 250. The mixture is then transferred, after homogenization, into an autoclave. The precursor gel is then transferred, after homogenization, into a 160 mL stainless steel reactor equipped with a four-blade inclined stirring system. The reactor is closed and then heated for 5 days at 170°C with stirring at 250 - 300 rpm. The crystallized product obtained is filtered, washed with deionized water and then dried overnight at 100°C. The solid product was analyzed by X-ray diffraction and identified as consisting of an IZM-2 zeolite.

[0071] Example 8: preparation of an IZM-2 zeolite according to the invention

[0072] 1.7 g of deionized water was mixed with 2.48 g of sodium hydroxide (99.5% by weight, Aldrich). 0.148 g of sodium aluminate (53% by weight, Carlo Erba) was added to the previous mixture, the resulting preparation was stirred for 15 minutes. 52.04 g of ethanol (98% by weight, Fisher) was added to the synthesis mixture and stirred for 10 minutes. Subsequently, 43.78 g of silicon alkoxide (TEOS, 25% by weight, Fluka) was incorporated into the synthesis mixture and stirred for 5 minutes. In order to promote the formation of the crystalline solid IZM-2, 0.55 g of IZM-2 zeolite seeds (5% of the total mass of tetravalent elements in SiC form) prepared according to example 1 are added to the synthesis mixture, which is kept stirring for 10 minutes. The precursor gel obtained has the following molar composition: 1 SiC: 0.004 AI2O3: 6.09 EtOH: 0.18 Na2O: 1 H2O, i.e. a SiO2 / Al2O3 ratio of 250.The mixture is then transferred, after homogenization, into an autoclave. The precursor gel is then transferred, after homogenization, into a 160 mL stainless steel reactor equipped with a four-blade inclined stirring system. The reactor is closed and then heated for 5 days at 190°C with stirring at 250-300 rpm. The crystallized product obtained is filtered, washed with deionized water and then dried overnight at 100°C. The solid product was analyzed by X-ray diffraction and identified as consisting of an IZM-2 zeolite.

[0073] Example 9: Preparation of an IZM-2 zeolite according to the invention 4.81 g of deionized water were mixed with 7.2 g of sodium hydroxide (99.5% by weight, Aldrich). 0.47 g of sodium aluminate (53% by weight, Carlo Erba) were added to the previous mixture, the preparation obtained was kept stirring for 15 minutes. 1.39 g of ethanol (98% by weight, Fisher) were added to the synthesis mixture and kept stirring for 10 minutes. Subsequently, 86.38 g of silicon alkoxide (TEOS, 25% by weight, Fluka) were incorporated into the synthesis mixture and kept stirring for 5 minutes. In order to promote the formation of the crystalline solid IZM-2, 2.163 g of IZM-2 zeolite seeds (10% of the total mass of tetravalent elements in SiO2 form) prepared according to example 1 are added to the synthesis mixture, which is kept stirring for 10 minutes.The precursor gel obtained has the following molar composition: 1 SiC: 0.007 AI2O3: 0.08 EtOH: 0.26 Na2O: 1 H2O, i.e. a SiC / ALOs ratio of 150. The mixture is then transferred, after homogenization, into an autoclave. The precursor gel is then transferred, after homogenization, into a 160 mL stainless steel reactor equipped with a four-blade inclined stirring system. The reactor is closed and then heated for 5 days at 170°C with stirring at 250 - 300 rpm. The crystallized product obtained is filtered, washed with deionized water and then dried overnight at 100°C.

[0074] The solid product was analyzed by X-ray diffraction and identified as consisting of an IZM-2 zeolite.

[0075] Example 10: preparation of an IZM-2 zeolite according to the invention

[0076] 1.7 g of deionized water was mixed with 2.36 g of sodium hydroxide (99.5% by weight, Aldrich). 0.24 g of sodium aluminate (53% by weight, Carlo Erba) was added to the previous mixture, the resulting preparation was stirred for 15 minutes. 52.00 g of ethanol (98% by weight, Fisher) was added to the synthesis mixture and stirred for 10 minutes. Subsequently, 43.79 g of silicon alkoxide (TEOS, 25% by weight, Fluka) was incorporated into the synthesis mixture and stirred for 5 minutes. In order to promote the formation of the crystalline solid IZM-2, 1.1 g of IZM-2 zeolite seeds (10% of the total mass of tetravalent elements in SiO2 form) prepared according to Example 1 are added to the synthesis mixture, which is kept stirring for 10 minutes. The precursor gel obtained has the following molar composition: 1 SiC: 0.007 AI2O3: 6.09 EtOH: 0.17 Na2O: 1 H2O, i.e. a SiO2 / Al2O3 ratio of 150.The mixture is then transferred, after homogenization, into an autoclave. The precursor gel is then transferred, after homogenization, into a 160 mL stainless steel reactor equipped with a four-blade inclined stirring system. The reactor is closed and then heated for 5 days at 190°C with stirring at 250-300 rpm. The crystallized product obtained is filtered, washed with deionized water and then dried overnight at 100°C. The solid product was analyzed by X-ray diffraction and identified as consisting of an IZM-2 zeolite.

[0077] Example 11: Synthesis not in accordance with the invention: Synthesis in a more dilute medium

[0078] 3.85 g of deionized water were mixed with 0.147 g of sodium hydroxide (99.5% by weight, Aldrich). 0.009 g of sodium aluminate (53% by weight, Carlo Erba) were added to the previous mixture, the resulting preparation was kept stirring for 15 minutes. 3.22 g of ethanol (98% by weight, Fisher) were added to the synthesis mixture and kept stirring for 10 minutes. Subsequently, 2.17 g of silicon alkoxide (TEOS, 25% by weight, Fluka) were incorporated into the synthesis mixture and kept stirring for 5 minutes. In order to promote the formation of the crystalline solid IZM-2, 0.067 g of IZM-2 zeolite seeds (10% of the total mass of tetravalent elements in SiO2 form) prepared according to Example 1 are added to the synthesis mixture, which is kept stirring for 10 minutes. The precursor gel obtained has the following molar composition: 1 SiC: 0.005 AI2O3: 7.6 EtOH: 0.21 Na2O: 24.3 H2O, i.e. a SiC / ALOs ratio of 193.The mixture is then transferred, after homogenization, into an autoclave. The autoclave is closed and then heated for 5 days at 170°C with stirring at 35 rpm using a rotating spit system. The resulting crystallized product is filtered, washed with deionized water and then dried overnight at 100°C.

[0079] The solid product was analyzed by X-ray diffraction and identified as consisting of Quartz (ICDD sheet, PDF 00-011-0252).

[0080] Example 12: Synthesis not in accordance with the invention: Synthesis in a more dilute medium

[0081] 5.63 g of deionized water was mixed with 0.21 g of sodium hydroxide (99.5% by weight, Aldrich). 0.018 g of sodium aluminate (53% by weight, Carlo Erba) was added to the previous mixture, the resulting preparation was kept stirring for 15 minutes. 0.085 g of ethanol (98% by weight, Fisher) was added to the synthesis mixture and kept stirring for 10 minutes. Subsequently, 3.92 g of silicon alkoxide (TEOS, 25% by weight, Fluka) was incorporated into the synthesis mixture and kept stirring for 5 minutes. In order to promote the formation of the crystalline solid IZM-2, 0.099 g of IZM-2 zeolite seeds (10% of the total mass of tetravalent elements in SiC form) prepared according to example 1 are added to the synthesis mixture, which is kept stirring for 10 minutes. The precursor gel obtained has the following molar composition: 1 SiC: 0.006 AI2O3: 0.11 EtOH: 0.17 Na2O: 19.3 H2O, i.e. a SiC / ALOs ratio of 174.The mixture is then transferred, after homogenization, into an autoclave. The autoclave is closed and then heated for 5 days at 170°C with stirring at 35 rpm using a rotating spit system. The resulting crystallized product is filtered, washed with deionized water and then dried overnight at 100°C.

[0082] The solid product was analyzed by X-ray diffraction and identified as consisting of Quartz (ICDD sheet, PDF 00-011-0252).

[0083] Example 13: Synthesis not in accordance with the invention: Synthesis without addition of ethanol 5.99 g of sodium hydroxide (99.5% by weight, Aldrich) were mixed with 0.249 g of sodium aluminate (53% by weight, Carlo Erba) and kept stirring for 15 minutes. Subsequently, 47.971 g of colloidal silica (Ludox HS40, 40% by weight, Aldrich) were incorporated into the synthesis mixture and kept stirring for 5 minutes. In order to promote the formation of the crystalline solid IZM-2, 1.92 g of IZM-2 zeolite seeds (10% of the total mass of tetravalent elements in SiO2 form) prepared according to Example 1 were added to the synthesis mixture, which was kept stirring for 10 minutes. The precursor gel obtained has the following molar composition: 1 SiO2: 0.004 AI2O3: 0.25 Na2O: 3 H2O, i.e. a SiO2 / Al2O3 ratio of 250. The mixture is then transferred, after homogenization, into an autoclave.The autoclave is closed and then heated for 5 days at 170°C with stirring at 35 rpm using a rotating spit system. The crystallized product obtained is filtered, washed with deionized water and then dried overnight at 100°C.

[0084] The solid product was analyzed by X-ray diffraction and identified as consisting of Quartz (ICDD sheet, PDF 00-011-0252). Example 14: Synthesis not in accordance with the invention: Synthesis without addition of ethanol or seed of the IZM-2 zeolite

[0085] 5.99 g of sodium hydroxide (99.5% by weight, Aldrich) were mixed with 0.245 g of sodium aluminate (53% by weight, Carlo Erba) and kept stirring for 15 minutes. Subsequently, 47.98 g of colloidal silica (Ludox HS40, 40% by weight, Aldrich) were incorporated into the synthesis mixture and kept stirring for 5 minutes. The precursor gel obtained has the following molar composition: 1 SiC: 0.004 AI2O3: 0.25 Na2O: 4 H2O, i.e. a SiC / ALOs ratio of 250. The mixture is then transferred, after homogenization, into an autoclave. The autoclave is closed and then heated for 5 days at 170°C with stirring at 35 rpm with a rotating spit system. The crystallized product obtained is filtered, washed with deionized water and then dried overnight at 100°C.

[0086] The solid product was analyzed by X-ray diffraction and identified as consisting of Kenyaite (ICDD sheet, PDF 00-020-1157).

Claims

CLAIMS 1. Process for preparing a microporous IZM-2 solid or a structuring-free IZM-2 zeolite comprising at least the following steps: i) mixing, in the presence of at least one alcohol and water, at least one source of at least one tetravalent element X in oxide form XO2, at least one source of at least one trivalent element in oxide form Y2O3, at least one source of at least one alkali and / or alkaline-earth metal M of valence n, n being an integer greater than or equal to 1, and calcined IZM-2 zeolite seeds, the mixture having the following molar composition: XO2 / Y2O3 between 70 and 350, H2O / XO2 between 1 and 5, Alcohol / XO2 between 0.05 and 30, M2 / nO / XO2 between 0.05 and 0.45, in which Y is one or more trivalent element(s) chosen from the group formed by the following elements: aluminum, iron, boron, gallium X is one or more tetravalent element(s) chosen from the group formed by the following elements: silicon, germanium, titanium, M is one or more alkali and / or alkaline earth metal(s) chosen from lithium, sodium, potassium, calcium, magnesium and the mixture of at least two of these metals, the alcohol is chosen from the group formed by primary, secondary and tertiary alcohols, until a homogeneous mixture called precursor gel is obtained; ii) the hydrothermal treatment of said precursor gel obtained at the end of step i) at a temperature between 120 and 220°C, for a period between 1 day and 10 days until said IZM-2 zeolite is formed.

2. Method according to claim 1 in which X is silicon.

3. Method according to claim 2 in which the source of silicon is chosen from powdered silicas, silicic acid, colloidal silicas, dissolved silica and silicon alkoxides, alone or as a mixture.

4. The method of claim 3 wherein the silicon source is tetraethyl orthosilicate or TEOS.

5. Method according to one of claims 1 to 4 in which Y is aluminum.

6. Method according to claim 5 in which the source of aluminum in oxide form AI2O3 is an aluminum salt chosen from aluminum chlorides, aluminum nitrates, aluminum sulfates, sodium aluminates, alone or as a mixture.

7. Method according to claim 6 in which the source of aluminum in oxide form AI2O3 is sodium aluminate.

8. Method according to one of claims 1 to 7 in which the source of at least one alkali and / or alkaline earth metal M is sodium hydroxide.

9. Process according to one of claims 1 to 8 in which the calcined IZM-2 zeolite seeds are added to the mixture of step i) in a proportion of between 0.01 and 13%, preferably between 0.01 and 10% and more preferably between 0.01 and 5% of the total mass of the sources of said tetravalent and trivalent element(s) used in the reaction mixture, said seeds not being taken into account in the total mass of the sources of the tetravalent and trivalent elements.

10. Method according to one of claims 1 to 9 in which the alcohol added in step i) is ethanol.

11. Method according to one of claims 1 to 10 in which the mixture of step i) has the following molar composition: XO2 / Y2O3 between 100 and 260 H2O / XO2 between 1 and 3 Alcohol / XO2 between 0.065 and 20 M2 / nO / XO2 between 0.09 and 0.3

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