Molecular sieve boron SSZ-113

Abstract

There is provided a novel synthetic crystalline boron germanosilicate molecular sieve material called boron SSZ-113. Boron SSZ-113 can be synthesized using 1,3-bis(2,3-dimethyl-1H-imidazolium) propane dication as a structure directing agent. Boron SSZ-113 can be used in organic compound conversion reactions and / or sorption processes, particularly reforming reactions.

Description

Technical Field

[0001] This application claims priority to U.S. Provisional Patent Application No. 63 / 365,538, filed May 31, 2022, the entire disclosure of which is incorporated herein by reference in its entirety.

[0002] This disclosure relates to a novel synthetic crystalline molecular sieve, designated SSZ-113, that contains boron within its framework. This disclosure also relates to its synthesis.

Background Art

[0003] Molecular sieves are a commercially important class of materials having a unique crystal structure with a distinct pore structure as indicated by a unique X-ray diffraction (XRD) pattern. Molecular sieves also have a specific chemical composition. The crystal structure defines cavities and pores that are characteristic of a particular type of molecular sieve. Providing new molecular sieves that differ in crystal structure as well as composition can lead to unique catalysts or adsorption / separation materials. Altering the crystal structure is always difficult, but if successful, can provide benefits for new catalysts for organic compound conversion reactions. U.S. Patent Application Publication No. 2019 / 0256364 discloses the preparation of SSZ-113. However, it does not disclose boron SSZ-113.

Summary of the Invention

Means for Solving the Problems

[0004] According to this disclosure, a crystalline molecular sieve designated boron SSZ-113 is synthesized using 1,3-bis(2,3-dimethyl-1H-imidazolium) propane dication as a structure directing agent (SDA). It has been found that the synthesis was successful in providing a boron-containing molecular sieve having the SSZ-113 crystal structure.

[0005] In one aspect, a boron SSZ-113 molecular sieve having a powder X-ray diffraction pattern comprising at least the peaks in Table 3 below is prepared in its as-synthesized form.

[0006] In its as-synthesized and anhydrous form, the boron molecular sieve has the following molar relationship: [Table 1] (wherein T is a tetravalent element including silicon and germanium; Q + is 1,3-bis(2,3-dimethyl-1H-imidazolium)propane dication) and may have a chemical composition. In one embodiment, the ratio of TO2 / B2O3 is in the range of 15 to 20.

[0007] In its calcined form, the boron SSZ-113 molecular sieve has the following molar relationship: B2O3:(n)TO2 (wherein n is ≧10; T is a tetravalent element including silicon and germanium) and may have a chemical composition.

[0008] In a further aspect, a method for synthesizing a boron molecular sieve is provided. The method comprises providing a reaction mixture comprising (a)(1) a source of silicon oxide; (2) a source of germanium; (3) a source of boron; (4) 1,3-bis(2,3-dimethyl-1H-imidazolium)propane dihydroxide (Q); (5) a source of fluoride ions; and (6) water. The reaction mixture is then subjected to crystallization conditions sufficient to form crystals of the SSZ-113 boron molecular sieve. T is as described above.

[0009] The boron-containing molecular sieve is then treated to remove the structure directing agent (SDA) referred to as Q above. The SDA can be removed by calcination or by ozonation, for example at 150 °C. It has also been found that the SDA can be removed by treating the molecular sieve with dimethylformamide.

[0010] In yet a further aspect, there is provided a process for converting a raw material containing an organic compound into a conversion product, the process comprising contacting the raw material under organic compound conversion conditions with a catalyst comprising boron SSZ-113 molecular sieve.

[0011] Among other factors, the process can obtain boron SSZ-113 molecular sieve, which is a borongermanosilicate. This new molecular sieve prepared by the process imparts unique ability as a catalyst in organic compound conversion reactions, particularly reforming. The molecular sieve also finds significant value as an adsorption / separation material.

DETAILED DESCRIPTION OF THE INVENTION

[0012] Definitions The term "framework type" has the meaning described in "Atlas of Zeolite Framework Types" by Ch. Baerlocher, L. B. McCusker, and D. H. Olsen (Elsevier, Sixth Revised Edition, 2007).

[0013] The term "borongermanosilicate" refers to a crystalline microporous solid containing boron, germanium, and silicon oxide within its framework structure. The borongermanosilicate can be a "pure borongermanosilicate" (i.e., without other detectable metal oxides in its framework structure) or optionally substituted. When described as "optionally substituted", each framework can contain other atoms (e.g., Al, Ga, In, Fe, Ti, Zr) that replace one or more atoms not yet present in the parent framework.

[0014] As used herein, the term "as-synthesized" refers to the molecular sieve in that form after crystallization and before removal of the structure-directing agent.

[0015] As used herein, the term "anhydrous" is utilized to refer to a molecular sieve substantially free of both physically adsorbed water and chemically adsorbed water.

[0016] When used herein, the Group numbering scheme of the Periodic Table is as disclosed in Chem. Eng. News 1985, 63(5), 26 - 27.

[0017] Synthesis of Molecular Sieve This molecular sieve boron SSZ - 113 can be synthesized by (a) providing a reaction mixture comprising (1) a source of silicon oxide; (2) a source of germanium; (3) a source of boron; (4) 1,3 - bis(2,3 - dimethyl - 1H - imidazolium) propane dication, e.g., dihydroxide (Q); (5) a source of fluoride ions; and (6) water; and then (b) subjecting the reaction mixture to crystallization conditions sufficient to form crystals of the SSZ - 113 boron molecular sieve. When aluminum is present, it is present in only minor amounts. Thus, the framework contains a predominating amount of boron.

[0018] The reaction mixture has a composition within the ranges set forth in Table 2 with respect to molar ratios: [Table 2] (where T and Q are as described hereinabove).

[0019] Suitable sources of silicon oxide include colloidal silica, fumed silica, precipitated silica, alkali metal silicates, and tetraalkyl orthosilicates. FAU framework type zeolites, e.g., zeolite Y, can also be a source of silicon oxide. In such cases, the SiO2 / Al2O3 molar ratio of the zeolite is at least 250, preferably at least 300. In one embodiment, the molar ratio ranges from 300 to 500.

[0020] Sources of germanium can be germanium oxide and germanium alkoxides (e.g., germanium ethoxide, germanium isopropoxide); germanium-hydroxide and germanium carboxylate.

[0021] The molar ratio of Si:Ge can range from 4 to 12, for example, from 6 to 10.

[0022] The source of boron can include boric acid, which is preferred. Other suitable sources can be used, but are not preferred.

[0023] Sources of fluoride ions can include, for example, hydrogen fluoride, ammonium fluoride, and ammonium bifluoride.

[0024] Q can include the 1,3-bis(2,3-dimethyl-1H-imidazolium) propane dication represented by the following structure (1):

Chemical formula

[0025]

[0026] Suitable sources of Q are hydroxides and / or other salts of the diquaternary ammonium compound.

[0027] ​The reaction mixture can contain seed crystals of a boron SSZ-113 molecular sieve material, such as boron SSZ-113 obtained from a previous synthesis, in an amount of 0.01 to 10,000 ppm by weight of the reaction mixture (e.g., 100 to 5000 ppm by weight). The addition of seed crystals can be advantageous in reducing the time required for complete crystallization to occur. Further, the addition of seed crystals can result in an increased purity of the resulting product by promoting the nucleation and / or formation of boron SSZ-113 over undesirable phases.

[0028] It is noted that the reaction mixture components can be supplied from two or more sources. Also, two or more reaction components can be provided by one source. The reaction mixture can be prepared batchwise or continuously.

[0029] Crystallization and Post-Synthesis Processing The crystallization of the boron molecular sieve from the above reaction mixture can be carried out at a temperature of 125 °C to 200 °C (e.g., 150 °C to 170 °C) in a suitable reactor vessel (e.g., a polypropylene jar or a Teflon™-lined or stainless steel autoclave) under static, rotating, or stirring conditions for a time sufficient for crystallization to occur at the temperature used (e.g., 1 day to 20 days, or 2 days to 10 days). The hydrothermal crystallization process is typically carried out under pressure, such as in an autoclave, and preferably under autogenous pressure.

[0030] Once the boron-containing molecular sieve crystals are formed, the solid product can be recovered from the reaction mixture by standard mechanical separation techniques such as centrifugation or filtration. The recovered crystals are washed with water and then dried to obtain as-synthesized molecular sieve crystals of SSZ-113 boron. The drying step can be carried out at an elevated temperature (e.g., 75 °C to 150 °C) for several hours (e.g., about 4 to 24 hours). The drying step can be carried out under vacuum or at atmospheric pressure.

[0031] As a result of the crystallization process, the recovered crystalline molecular sieve product contains within its pore structure at least a portion of the structure-directing agent used in the synthesis. The as-synthesized molecular sieve is subjected to a treatment to remove some or all of the structure-directing agent used in its synthesis.

[0032] Removal of the structure-directing agent can be carried out by a heat treatment (e.g., calcination) in which the as-synthesized molecular sieve is heated at a temperature sufficient to remove some or all of the structure-directing agent. A pressure lower than atmospheric pressure can be used for the heat treatment, but atmospheric pressure is desirable for simplicity. The heat treatment can be carried out at a temperature of at least 370 °C for at least 1 minute and generally less than 20 hours (e.g., 1 to 12 hours). The heat treatment can be carried out at a temperature up to 925 °C. For example, the heat treatment can be carried out at a temperature of 400 °C to 600 °C in the presence of an oxygen-containing gas.

[0033] Alternatively, or in addition, the structure-directing agent can be removed by treatment with ozone. See, for example, A.N. Parikh et al., Micropor. Mesopor. Mater. 2004, 76, 17 - 22. In one embodiment, the use of ozone is preferred in that it gives a higher micropore volume. It has also been found that the SDA can be removed by treatment with dimethylformamide, for example, by treatment at about 150 °C.

[0034] Characterization of the Molecular Sieve In its as-synthesized and anhydrous form, the boron-containing molecular sieve SSZ-113 can have a chemical composition including the following molar relationships set forth in Table 1: [Table 1] (wherein T is a tetravalent element including silicon and germanium; and Q+ includes the 1,3-bis(2,3-dimethyl-1H-imidazolium)propane dication). In one embodiment, the ratio of TO2 / B2O3 is in the range of 15 to 20.

[0035] It should be noted that the as-synthesized form of the SSZ-113 molecular sieve with boron in its as-synthesized form can have a molar ratio different from the molar ratio of the reactants of the reaction mixture used to prepare the as-synthesized form. This result can occur due to the incomplete incorporation of 100% of the reactants of the reaction mixture into the crystals (formed from the reaction mixture).

[0036] In its calcined form, the molecular sieve boron SSZ-113 can have the following molar relationship: B2O3:(n)TO2 (wherein n is ≥ 10 (for example, 15 or more, or in the range of 15 - 20); and T is a tetravalent element including silicon and germanium).

[0037] The as-synthesized and calcined forms of boron SSZ-113 have characteristic powder X-ray diffraction patterns. In the as-synthesized form of the molecular sieve, it contains at least the lines listed in Table 3 below, and in the calcined form of the molecular sieve, it contains at least the peaks listed in Table 4 below.

Table 3

Table 4

[0038] The powder X-ray diffraction patterns presented in this specification were collected by standard techniques. The radiation was CuKα radiation. The peak height and position as a function of 2θ, where θ is the Bragg angle, were read from the relative intensities of the peaks (adjusted with respect to the background), and the lattice plane spacing d corresponding to the recorded lines could be calculated.

[0039] Small variations in the diffraction pattern can result from variations in the molar ratio of the framework species of the sample due to changes in the lattice constant. Additionally, irregular substances and / or sufficiently small crystals will affect the shape and intensity of the peaks, resulting in significant peak broadening. Small variations in the diffraction pattern can also result from variations in the organic compounds used in the preparation. Calcination can also cause a small shift in the XRD pattern. Despite these small perturbations, the basic crystal lattice structure remains unchanged.

[0040] Sorption and Catalysis This molecular sieve boron SSZ - 113 (with some or all of Q+ removed) can be used as an adsorbent or as a catalyst to catalyze a variety of organic compound conversion processes, including many that are currently of commercial / industrial importance. A particular use of the catalyst containing boron SSZ - 113 is the reforming reaction, especially when the catalyst contains platinum.

[0041] Catalytic reforming is one of the basic petroleum refining processes for reforming light hydrocarbon raw materials, often referred to as naphtha feedstocks. Products obtained from catalytic reforming can include high-octane gasoline, aromatics (such as benzene, toluene, xylene, and ethylbenzene), and / or hydrogen, which are useful as automotive fuels. Reactions typically involved in catalytic reforming include dehydrocylization, isomerization, and dehydrogenation of naphtha-range hydrocarbons, and dehydrogenation cyclization and dehydrogenation of straight-chain and slightly branched alkanes and dehydrogenation of cyclic paraffins result in the production of aromatics. Dealkylation and hydrocracking are generally not desirable due to the low value of the resulting light hydrocarbon products.

[0042] The boron SSZ-113 catalyst used in the reforming reaction will often contain a Group VIII metal such as platinum or palladium, or a second catalytic metal that acts as a promoter in addition to the Group VIII metal. Examples of metals useful as promoters include rhenium, tin, tungsten, germanium, cobalt, nickel, rhodium, ruthenium, iridium, or combinations thereof. The catalytic metal or metals can be dispersed on a support such as alumina, silica, or silica-alumina.

[0043] The boron SSZ-113 modified catalyst can be used in the form of pellets, tablets, granules, fragments, or various special shapes, and can be arranged as a fixed bed in the reaction zone. The feedstock can pass through the reaction zone in the form of a liquid phase, a gas phase, or a mixed phase, either rising, falling, or in a radial flow. Alternatively, the modified catalyst can be used in a moving bed or a fluidized solid process where the feedstock rises and passes through a turbulent bed of finely divided catalyst. However, a fixed bed system or a dense phase moving bed system is preferred due to less catalyst consumption and other operational advantages. In a fixed bed system, the feed material is preheated to the desired reaction temperature (by any suitable heating means) and then passed through a reaction zone containing a fixed bed of catalyst. This reaction zone can be one or more separate reactors having suitable means for maintaining the desired temperature at the reactor inlet. Since the reforming reaction is typically endothermic in nature, the temperature must be maintained.

[0044] The actual reforming conditions often depend, at least in part, on the feedstock used, whether it is highly aromatic, paraffinic, or naphthenic, and on the desired octane number of the product and the desired amount of hydrogen production.

Examples

[0045] The following examples are intended to be non-limiting.

[0046] (Example 1) To a 23 ml reactor Teflon cup weighed with tare, 5 millimoles of SDA 1,3-bis(2,3-dimethyl-1H-imidazolium) propane dihydroxide solution was added. Then, 0.54 grams of Tosoh Corporation's HUA-390 FAU zeolite (SAR of about 250), 0.10 grams of GeO2 and 0.06 grams of H3BO3 (boric acid) were added. After reducing the H2O / TO2 ratio to 7 by evaporation for several days in a hood, 0.20 grams of 50% HF was given to the reactants, and then the mixture was sealed and heated at 160 °C for 7 days while rotating at 43 RPM. After cooling and collecting the sample from filtration and washing, the XRD data indicates that it is boron-containing SSZ-113 having the characteristic peaks in Table 3.

[0047] Next, as-manufactured boron germanosilicate SSZ-113 can be calcined in air at 540 °C using a ramp program of holding at 1 °C to 120 °C / min for 2 hours, ramping to 540 °C at 1 °C / min, holding for 4 hours, and cooling in the oven.

[0048] The XRD pattern remains essentially unchanged.

Table A

[0049] (Example 2) Platinum addition

[0050] 2.68 grams of calcined borogermano SSZ-113 obtained from Example 1 are dispersed in 64 grams of water, then 0.05 grams of platinum tetramine chloride hydrate is mixed in, and the solution is stirred at room temperature for 24 hours. The solid is then collected, dried, calcined in air at 300 °C (for 3 hours at that temperature), then pelletized, sieved to 24 / 40 mesh chips, and placed in a reactor.

[0051] (Example 3) Pretreatment of naphtha reforming catalyst

[0052] The naphtha reforming catalyst prepared in Example 2 is sulfided. The sulfidation reaction was carried out in a downflow fixed bed reactor system. The procedure is described as follows:

[0053] The catalyst was sieved into 24 - 40 chips and then placed in the center of a stainless - steel tubular reactor. The catalyst (with a dry weight of 0.53 g measured by TGA (Thermogravimetric Analysis) at 1112°F) was first dried in a N₂ flow (300 ml / min) from room temperature to 400°F at a heating rate of 10°F / min and maintained at 400°F for 30 minutes. For the reduction of platinum in the catalyst, it was then heated in an H₂ flow (300 ml / min) from 400°F to 900°F at a heating rate of 5°F / min and maintained at 900°F for 30 minutes. Finally, the catalyst was cooled to 800°F and the sulfidation reaction was initiated.

[0054] The feedstock applied to the sulfidation reaction was anhydrous n - octane containing 200 ppm sulfur (as dimethyldisulfide). Sulfidation was carried out at 800°F and atmospheric pressure for 60 minutes. The flow rates of H₂ and the liquid feedstock were 30 ml / min and 0.43 ml / min, respectively. After sulfidation, to remove excess sulfur species occluded in and / or on the surface of the catalyst pores, the catalyst was heated in an H₂ flow (300 ml / min) from 800 to 900°F within a few minutes and then further heated at 900°F for 30 minutes. Finally, the catalyst was heated or cooled to the preset reaction temperature (e.g., 850 or 950°F) within 2 hours in the same H₂ flow (300 ml / min) in preparation for the start of the naphtha catalytic reforming test in Example 4.

[0055] (Example 4) Procedure for the naphtha catalytic reforming test

[0056] After the sulfidation procedure described in Example 3, the naphtha catalytic reforming reaction was carried out as described below.

[0057] The catalyst was heated or cooled to the preset reaction temperature (950°F in Example 6) within 2 hours in the same H₂ flow (300 ml / min) in preparation for the start of the naphtha catalytic reforming test in this example as described in Example 3. At the same time, the reactor system was pressurized to the preset pressure (150 psig in Example 6). During this time, the H₂ flow was adjusted to the preset flow rate (14 ml / min in Example 6). The feed rate was 1.55 ml / h (Example 6).

[0058] In Example 6, the naphtha catalytic reforming experiment was carried out at a hydrocarbon WHSV of 2.2 and a molar ratio of hydrogen to hydrocarbon of 3.0 using the naphtha feedstock described in Example 5.

[0059] (Example 5) Feedstock for naphtha catalytic reforming test

[0060] The GC analysis data obtained from the feedstock used in the naphtha catalytic reforming test of the present invention are given in Table 5 together with the GC results of Example 6 for the naphtha catalytic reforming test products on the catalysts described in Examples 1 and 2. The GC data were obtained by on-line analysis.

[0061] (Example 6) Products obtained from naphtha catalytic reforming test

[0062] The GC analysis data obtained from the feedstock of Example 5 used in the naphtha catalytic reforming test are given in Table 5 together with the results of this example for the naphtha catalytic reforming test products on the catalyst described in Example 3. The naphtha catalytic reforming experiment was carried out at 950°F, 150 psig, a hydrocarbon WHSV of 2.2 and a molar ratio of hydrogen to hydrocarbon of 3.0.

[0063] The GC results obtained from the feedstock (Example 5) used in the naphtha catalytic reforming test and from the naphtha catalytic reforming test products (Example 6) on the catalyst described in Example 3 are shown in Table 5 below. Reaction conditions: 950°F, 150 psig, a hydrocarbon WHSV of 2.2 and a molar ratio of hydrogen to hydrocarbon of 3.0.

Table 5

[0064] The products in Table 5 show an increase in aromatics and octane gasoline. Boron SSZ-113 was successful in reforming the raw materials of Example 5.

[0065] As used in this disclosure, the terms "comprises" or "comprising" are intended to be non-limiting transitional phrases that mean the inclusion of the stated elements but do not necessarily exclude other unstated elements. The phrase "consists essentially of" or "consisting essentially of" is intended to mean the exclusion of other elements that have essential importance to the composition. The phrase "consisting of" or "consists of" is intended to be a transitional phrase that means the exclusion of all except the recited elements, except for trace impurities.

[0066] All patents and publications cited herein are incorporated herein by reference to the extent that they are not inconsistent with this specification. It will be understood that some of the structures, functions, and operations of the above-described embodiments are not necessary to practice the present invention and are included herein merely for the sake of completeness of the exemplary embodiments or embodiments. Further, it will be understood that the specific structures, functions, and operations described in the above-cited patents and publications can be practiced in conjunction with the present invention, but they are not essential to its practice. Accordingly, it is understood that the present invention can be practiced otherwise than as specifically described without actually departing from the spirit and scope of the present invention as defined by the appended claims.

Claims

1. A molecular sieve containing boron, having a powder X-ray diffraction pattern in its as-synthesized form with the following peaks: 【Table 3】

2. The molecular sieve according to claim 1, having a composition containing the following molar relationship: B ２ O ３ :(n) TO ２ (wherein n is ≥ 10; and T is a tetravalent element including silicon and germanium).

3. The molecular sieve according to claim 1, having a composition containing the following molar relationship: B ２ O ３ : (n) TO ２ (wherein n is ≥ 15; and T is a tetravalent element including silicon and germanium).

4. The following molar relationship: 【Table 1A】 wherein T is a tetravalent element containing silicon and germanium; Q － contains 1,3-bis(2,3-dimethyl-1H-imidazolium)propane dication), the molecular sieve according to claim 1 having a chemical composition containing).

5. The molecular sieve according to claim 4, which is sulfided and contains a Group VIII metal.

6. The molecular sieve according to claim 5, wherein the Group VIII metal is platinum or palladium.

7. A method for synthesizing the molecular sieve according to claim 1, comprising: (a) preparing a reaction mixture containing the following: (1) a source of silicon oxide; (2) a source of germanium; (3) a source of boron; (4) 1,3-bis(2,3-dimethyl-1H-imidazolium) propane dication (Q); (5) a source of fluoride ions; and (6) water; and (b) subjecting the reaction mixture to crystallization conditions sufficient to form crystals of the molecular sieve. The above method.

8. The method according to claim 7, wherein the reaction mixture has the following composition in terms of molar ratio: 【Table 2A】 (wherein T is a tetravalent element including silicon and germanium).

9. The method according to claim 7, wherein the reaction mixture has a molar ratio as follows: 【Table 2B】 (wherein T is a tetravalent element including silicon and germanium).

10. wherein said source of silicon oxide comprises zeolite Y having an SiO ２ / Al ２ O ３ ratio of at least 250, the method according to claim 7.

11. The method according to claim 7, wherein the crystallization conditions include a temperature of 125°C to 200°C.

12. A method for converting a raw material containing an organic compound into a conversion product, comprising contacting the raw material with a catalyst containing the molecular sieve according to claim 5 under organic compound conversion conditions.

13. A method for converting a raw material containing an organic compound into a conversion product, comprising contacting the raw material with a catalyst containing the molecular sieve according to claim 6 under organic compound conversion conditions.

14. The method according to claim 12, wherein the conversion reaction is reforming.

15. The method according to claim 13, wherein the conversion reaction is reforming.

16. A method for ion-exchanging a metal, the method comprising contacting a stream containing a heavy metal with the molecular sieve according to claim 4.

Images