Boron-SSZ-41, its synthesis and uses

Abstract

A novel synthetic crystalline molecular sieve material, designated boron SSZ-41, is provided. Boron SSZ-41 is a boron zincosilicate molecular sieve with the SSZ-41 framework structure. It can be synthesized using 1,1l'-(1l,4-butanediyl)bis[4-aza-1-azoniabicyclo[2.2.2]octane] dication as a structure-directing agent. Boron zincosilicate SSZ-41 can be used in organic compound conversion reactions and / or sorption processes.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Application No. 63 / 402,820, filed August 31, 2022, the complete disclosure of which is incorporated herein by reference in its entirety.

[0002] The present disclosure relates to small crystal size SSZ-41 molecular sieves, their synthesis, and their use as adsorbents and catalysts for organic conversion reactions. [Background technology]

[0003] Molecular sieves are a commercially important class of materials with specific chemical compositions and unique crystalline structures with distinct pore structures revealed by distinctive X-ray diffraction (XRD) patterns. The crystalline structure defines the cavities and pores characteristic of a particular type of molecular sieve.

[0004] Providing new molecular sieves with different crystal structures and compositions can lead to unique catalytic or adsorption / separation materials. Changing the crystal structure is always difficult, but if successful, it can be rewarded with new catalysts for organic compound conversion reactions. U.S. Patent No. 5,591,421 discloses the preparation of SSZ-41. However, it does not disclose boron SSZ-41. Summary of the Invention

[0005] In accordance with the present disclosure, a new crystalline molecular sieve, designated boron SSZ-41, is synthesized using 1,1'-(1,4-butanediyl)bis[4-aza-1-azoniabicyclo[2.2.2]octane] dication as a structure directing agent (SDA). This synthesis has been found to be successful in providing a boron-containing molecular sieve, boron zincosilicate, having the SSZ-41 crystal structure.

[0006] In a second aspect, a method for synthesizing a boron zincosilicate molecular sieve having a framework structure of SSZ-41 is provided, comprising: (1) forming a reaction mixture comprising: (a) a silicon source, such as an FAU framework zeolite; (b) a source of zinc; (c) a structure directing agent (Q) comprising 1,1'-(1,4-butanediyl)bis[4-aza-1-azoniabicyclo[2.2.2]octane] dication; (d) a source of boron; (e) a source of hydroxide ions; (f) water; and (g) seeds; and (2) subjecting the reaction mixture to crystallization conditions sufficient to form boron molecular sieve crystals.

[0007] In a third aspect, a method for converting a feedstock comprising organic compounds to conversion products is provided, the method comprising: (i) contacting the feedstock with a catalyst under organic compound conversion conditions to produce an eluate containing the conversion products, wherein the catalyst comprises a boron zincosilicate molecular sieve having a framework structure of SSZ-41; and (ii) recovering the conversion products from the eluate.

[0008] Among other factors, this method makes it possible to obtain boron zincosilicate SSZ-41 molecular sieves. This new molecular sieve prepared by this method can provide unparalleled catalytic capabilities for organic compound transformation reactions. Molecular sieves are also of great value as adsorption / separation materials. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a graph showing the solid state MAS NMR of the product of Example 1. The figure shows that the boron is present in a tetrahedral configuration. DETAILED DESCRIPTION OF THE INVENTION

[0010] definition The term "framework type" has the meaning set forth in "Atlas of Zeolite Framework Types" by Ch. Baerlocher, L.B. McCusker and D.H. Olsen (Elsevier, 6th revised edition, 2007).

[0011] The term "as-synthesized" is used herein to refer to the molecular sieve in the form after crystallization and before removal of the structure directing agent.

[0012] The term "anhydrous" is used herein to refer to a molecular sieve that is substantially free of both physically and chemically adsorbed water.

[0013] As used herein, the numbering scheme for the Periodic Table Groups is as disclosed in Chem. Eng. News 1985, 63(5), 26-27.

[0014] Synthesis of boron molecular sieves A boron zincosilicate molecular sieve having an SSZ-41 framework structure can be synthesized by (1) forming a reaction mixture containing (a) a source of silicon; (b) a source of zinc; (c) a structure directing agent (Q) comprising 1,1'-(1,4-butanediyl)bis[4-aza-1-azoniabicyclo[2.2.2]octane] dication; (d) a source of boron; (e) a source of hydroxide ions; (f) water; and (g) seeds; and (2) subjecting the reaction mixture to crystallization conditions sufficient to form boron zincosilicate molecular sieve crystals.

[0015] In one embodiment, the silicon source can include a FAU framework-type zeolite.

[0016] The reaction mixture was prepared in terms of molar ratios as shown in Table 1: [Table 1] and Q comprises a 1,1'-(1,4-butanediyl)bis[4-aza-1-azoniabicyclo[2.2.2]octane] dication.

[0017] The silicon source can include an FAU framework zeolite. The FAU framework zeolite can be zeolite Y. The FAU framework zeolite can be an ammonium form zeolite or a hydrogen form zeolite (e.g., NH + Forms Zeolite Y, H + The FAU framework-type zeolite may be a zeolite Y (form of zeolite Y). The FAU framework-type zeolite may have a SiO2 / Al2O3 molar ratio of at least 300 (e.g., 300 to 500, 300 to 600). The FAU framework-type zeolite may comprise two or more zeolites. Typically, the two or more zeolites are zeolite Y having different silica-to-alumina molar ratios. Examples of suitable aluminosilicate zeolites include Y zeolites CBV720, CBV760, and CBV780 available from Zeolyst International, and Y zeolites HSZ-HUA385 and HSZ-HUA390 available from Tosoh. The FAU framework-type zeolite may be used as the sole or primary source of silicon in the reaction mixture. Aluminum-free silicon sources may be very useful. In one embodiment, the silicon source is Al-free.

[0018] The FAU framework-type zeolite may be a zinc-exchanged zeolite (e.g., zinc-exchanged zeolite Y), where the zeolite may also be the source of zinc metal in the reaction mixture. "Zinc-exchanged zeolite" refers to an aluminosilicate zeolite in which zinc metal is located on the surface and / or within the cages and / or pores of the aluminosilicate zeolite. This does not refer to an aluminosilicate in which zinc metal is in the aluminosilicate framework.

[0019] Additionally or alternatively, the source of zinc can be a zinc salt of an organic or inorganic acid. Representative zinc salts include zinc formate, zinc acetate, zinc citrate, zinc chloride, zinc bromide, zinc nitrate, and zinc sulfate.

[0020] When lithium is added, sources of lithium include lithium hydroxide and other lithium salts, especially lithium halides such as lithium chloride.

[0021] Suitable sources of boron include, and are preferred to be, boric acid.

[0022] The source of hydroxide ions can be lithium hydroxide. A structure directing agent can also be used to provide the hydroxide ions.

[0023] The structure directing agent (Q) has the following structure (1): [ka] 1,1'-(1,4-butanediyl)bis-4-aza-1-azoniabicyclo[2.2.2]octane dication ([DABCO-(CH2)4-DABCO] 2+ ").

[0024] Suitable sources of Q are hydroxides, chlorides, bromides, and / or other salts of diquaternary ammonium compounds.

[0025] The reaction mixture also contains seeds, typically boron zincosilicate SSZ-41 from a previous synthesis, desirably in an amount of 0.1 to 20 wt. % (e.g., 0.5 to 10 wt. %) based on the total weight of SiO in the reaction mixture. Seeding can be advantageous to improve the selectivity of the boron zincosilicate SSZ-41 and / or shorten the crystallization process. While boron SSZ-41 seeds are preferred, in one embodiment, seeds of conventional SSZ-41 zeolite made without boron can be used.

[0026] It should be noted that the reaction mixture components can be supplied by more than one source. Also, two or more reaction components can be provided by a single source. The reaction mixture can be prepared either batchwise or continuously.

[0027] Crystallization and post-synthesis treatment Crystallization of the desired molecular sieve from the reaction mixture can be carried out under static, rotating, or stirred conditions in a suitable reaction vessel, such as a polypropylene jar, or a Teflon-lined or stainless steel autoclave, at a temperature of 100°C to 200°C (e.g., 130°C to 180°C) for a time sufficient for crystallization to occur at the temperature used, e.g., about 1 day to 14 days (e.g., 3 days to 10 days). Crystallization is typically carried out under pressure in the autoclave, such that the reaction mixture is subjected to autogenous pressure.

[0028] Once the desired molecular sieve crystals are formed, the solid product can be separated from the reaction mixture by standard mechanical separation techniques such as centrifugation or filtration. The recovered crystals are washed with water and then dried for a few seconds to a few minutes (e.g., 5 seconds to 10 minutes for flash drying) or for several hours (e.g., 4 hours to 24 hours for oven drying at 75°C to 150°C) to obtain the as-synthesized molecular sieve crystals. The drying step can be carried out under vacuum or atmospheric pressure.

[0029] As a result of the crystallization process, the recovered crystalline molecular sieve product contains within its pores at least a portion of the structure directing agent used in its synthesis.

[0030] The as-synthesized molecular sieve may be subjected to heat treatment, ozone treatment, or other treatment to remove some or all of the structure-directing agent used in the synthesis. Removal of the structure-directing agent can be accomplished using a heat treatment (e.g., calcination), in which the as-synthesized material is heated in an atmosphere selected from air, nitrogen, or a mixture thereof at a temperature sufficient to remove some or all of the structure-directing agent. Although subatmospheric pressures may be used for the heat treatment, atmospheric pressure is preferred for convenience. The heat treatment can be carried out at a temperature of at least 370°C (e.g., 400°C to 700°C) for at least 1 minute, generally for up to 20 hours (e.g., 1 to 8 hours).

[0031] To the extent desired, any extraframework metal cations (e.g., Li) in the molecular sieve may be present. + ) can be replaced with other cations by ion exchange according to techniques well known in the art. Replacement cations include metal ions, hydrogen ions, hydrogen precursors (e.g., ammonium ions), and mixtures thereof.

[0032] Molecular sieve characterization In the as-synthesized and anhydrous forms, the boron zincosilicate SSZ-41 molecular sieve has the following molar ratios: [Table 2] and Q comprises a 1,1'-(1,4-butanediyl)bis[4-aza-1-azoniabicyclo[2.2.2]octane] dication.

[0033] Thus, the composition can be said to include a molar relationship of B2O3:(n)(SiO2), where in one embodiment n≧10, in another embodiment n≧15, and in one embodiment n is in the range of about 15-20.

[0034] The boron molecular sieve SSZ-41 has a powder X-ray diffraction (XRD) pattern that includes at least the peaks listed in Table 3 below for the as-synthesized form of the molecular sieve, and at least the peaks listed in Table 4 below for the calcined form of the molecular sieve. [Table 3] [Table 4]

[0035] The X-ray diffraction data reported herein were collected by standard techniques using copper Kα radiation. The determination of the parameter 2θ is subject to both human and mechanical error, the combination of which can impose an uncertainty of approximately ±0.10° on each reported value of 2θ. When converted to the corresponding d-spacing value using Bragg's law, the d-spacing value is understood to have a deviation determined based on a corresponding deviation of ±0.10 degrees 2θ. The relative intensity of a line, I / Io, represents the ratio of the peak intensity to the intensity of the most intense line above background. Relative intensities are given by the symbols VS = very strong (>60), S = strong (≧40 and ≦60), M = moderate (≧20 and <40), and W = weak (<20).

[0036] Slight variations in the diffraction pattern can result from variations in the molar ratio of the framework species in the sample, resulting in changes in the lattice constants. In addition, irregular materials and / or sufficiently small crystals can affect the shape and intensity of the peaks, resulting in significant peak broadening. Slight variations in the diffraction pattern can also be due to variations in the organic compounds used in the preparation. Calcination can also cause slight shifts in the XRD pattern. Despite these slight perturbations, the basic crystal lattice structure remains unchanged. [Industrial Applicability]

[0037] The molecular sieve boron zincosilicate SSZ-41 (from which some or all of the structure directing agent has been removed) can be used as an adsorbent or as a catalyst to catalyze a wide variety of organic compound conversion processes. Of particular use is the use of boron zincosilicate SSZ-41 in reforming processes.

[0038] Catalytic reforming is one of the fundamental petroleum refining processes for improving light hydrocarbon feedstocks, often referred to as naphtha feedstocks. Products from catalytic reforming can include high-octane gasoline useful as motor fuel, aromatics (e.g., benzene, toluene, xylenes, and ethylbenzene), and / or hydrogen. Reactions typically involved in catalytic reforming include dehydrocyclization, isomerization, and dehydrogenation of naphtha-range hydrocarbons, resulting in the dehydrocyclization and dehydrogenation of linear and slightly branched alkanes and the dehydrogenation of cycloparaffins to produce aromatics. Dealkylation and hydrocracking are generally undesirable due to the low value of the resulting light hydrocarbon products.

[0039] The boron zincosilicate SSZ-41 catalysts used in reforming reactions often contain a Group VIII metal, such as platinum or palladium, or a Group VIII metal and a second catalytic metal that acts as a promoter. Examples of metals useful as promoters include rhenium, tin, tungsten, germanium, cobalt, nickel, rhodium, ruthenium, iridium, or combinations thereof. The catalytic metal(s) may be dispersed on a support such as alumina, silica, or silica-alumina.

[0040] As with many catalysts, it may be desirable to incorporate the boron zincosilicate SSZ-41 material of the present invention with other materials that can withstand the temperatures and other conditions used in organic conversion processes. Such materials include active and inactive materials, as well as synthetic or naturally occurring zeolites, and inorganic materials, such as clays, silica, and / or metal oxides, such as alumina. The inorganic materials may be in their naturally occurring form or in the form of gelatinous precipitates or gels, including mixtures of silica and metal oxides. The use of materials with boron SSZ-41 (i.e., materials that are active and present in combination or in the synthesis of new crystals) tends to alter the conversion and / or catalytic selectivity in a particular organic conversion process. Inactive materials suitably function as diluents to control the amount of conversion in a given process, so that products can be obtained in an economical and orderly manner without other means of controlling the reaction rate. These materials may be incorporated into naturally occurring clays (e.g., bentonite and kaolin) to improve the compressive strength of the catalyst under commercial operating conditions. These materials (i.e., clays, oxides, etc.) function as binders for the catalyst. It is desirable to provide a catalyst with good compressive strength because, in commercial applications, it is desirable to prevent the catalyst from breaking down into a powdery material. These clay and / or oxide binders have typically been used solely to improve the compressive strength of the catalyst.

[0041] Naturally occurring clays that can be composited with SSZ-41 materials include the montmorillonite and kaolin families, including sub-bentonites. Kaolin is commonly known as Dixie, McNamee, Georgia, and Florida clays, or others, and the primary mineral component in kaolin is halloysite, kaolinite, dickite, nacrite, or anauxite. Such clays can be used in their original, unprocessed state as mined, or first subjected to calcination, acid treatment, or chemical modification. Binders useful for composites with SSZ-41 also include inorganic oxides, such as silica, zirconia, titania, magnesia, beryllia, alumina, and any combination thereof.

[0042] In addition to the aforementioned materials, boron zincosilicate SSZ-41 can be composited with porous matrix materials such as silica-alumina, silica-magnesia, silica-zirconia, silica-thoria, silica-beryllia, silica-titania, and ternary compositions such as silica-alumina-thoria, silica-alumina-zirconia, silica-alumina-magnesia, and silica-magnesia-zirconia.

[0043] The relative proportions of boron zincosilicate SSZ-41 and inorganic oxide matrix can vary widely, with the boron zincosilicate SSZ-41 content ranging from 1 to 90% by weight of the composite (e.g., from 2 to about 80% by weight).

[0044] The boron zincosilicate SSZ-41 reforming catalyst can be used in the form of pills, pellets, granules, broken pieces, or various special shapes arranged as a fixed bed in the reaction zone, through which the charge stock can be passed in either upward, downward, or radial flow in liquid, vapor, or mixed phase. Alternatively, the reforming catalyst can be used in a moving bed or fluidized solid process, in which the charge feed is passed upward through a turbulent bed of finely divided catalyst. However, due to lower catalyst attrition and other operational advantages, fixed-bed or dense-phase moving-bed systems are preferred. In fixed-bed systems, the feed is preheated (by any suitable heating means) to the desired reaction temperature and then passed to a reaction zone containing a fixed bed of catalyst. This reaction zone may be one or more separate reactors with appropriate means for maintaining the desired reactor inlet temperature. Because the reforming reaction is typically endothermic in nature, temperature must be maintained.

[0045] The actual reforming conditions will depend, at least in part, on whether the feed used is highly aromatic, paraffinic, or naphthenic, and often on the desired octane number of the product and the desired hydrogen production. [Example]

[0046] The following illustrative examples are intended to be non-limiting.

[0047] Example 1 The synthesis of boron zincosilicate SSZ-41 is described below. To a Parr 23 ml reactor Teflon cup was added 0.05 grams of LiOH (anhydrous), 0.136 grams of zinc acetate dihydrate, 0.06 grams of boric acid, 0.90 grams of Tosoh HUA 390 (FAU-type zeolite), 3.33 grams of 1.27 M SDA solution, and 5.25 grams of water. Seeds of conventional SSZ-41 zeolite prepared without boron were added (3% of total SiO2 solids). The Si / B ratio in this synthesis is approximately 15. The reaction mix was heated at 160°C for 10 days with 43 RPM tumbling. The product was a good boron zincosilicate SSZ-41 material. Product analyzed for boron = 0.16 wt% boron. Solid-state MAS NMR (see figure) demonstrates that the boron is present in a tetrahedral configuration, indicating lattice substitution.

[0048] Example 2 Calcination of boron zincosilicate SSZ-41 The product from Example 1 was calcined under a nitrogen sweep in a ramp program to 540°C, at which time the SDA was removed. The product retained the XRD pattern of SSZ-41.

[0049] Example 3 Boron to aluminum exchange An exchange experiment was also conducted to demonstrate that the borosilicate product of Example 1 also possesses boron in the framework. 0.4 grams of calcined boron zincosilicate SSZ-41 (Example 2) was placed in a vial and 20 grams of a 0.2 molar solution of aluminum nitrate nonahydrate was added to obtain an excess of Al over B in the zeolite. The solution was heated without stirring at 95°C for 4 days. The product was recovered by filtration and washed first with 0.1% HCl (to remove any Al still in solution) and then with water. The product was dried, and XRD showed no change. The new aluminum-exchanged boron SSZ-41 was then subjected to an acidity test using n-propylamine as the adsorbate. Strong acid sites (characteristic of Al in the zeolite lattice) were observed here, with a measurement of nearly 100 micromoles of ammonia measured at temperatures above 400°C.

[0050] Example 4 Platinum addition

[0051] The calcined ammonium-exchanged zeolite of Example 2 is added to 12.9 grams of water (0.63 grams) along with 0.0126 grams of platinum from platinum tetraamine chloride hydrate. Stirring is carried out at room temperature for 24 hours, and then the solid is filtered and calcined to 300°C. The solid is then pressed, meshed into 24 / 40 chips, and loaded into a reactor.

[0052] Example 5 Pretreatment of catalytic naphtha reforming catalyst

[0053] The catalytic naphtha reforming catalyst prepared in Example 4 was sulfided. The sulfiding reaction was carried out in a downflow fixed-bed reactor system. The procedure is described as follows:

[0054] The catalyst was meshed into 24-40 chips and then loaded into the center of a stainless steel tube reactor. The catalyst (dry weight 0.53 g, determined by TGA (thermogravimetric analysis) at 1112 °F) was first dried in N2 flow (300 ml / min) at a heating rate of 10 °F / min from room temperature to 400 °F and held at 400 °F for 30 minutes. To reduce the platinum in the catalyst, the catalyst was subsequently heated in H2 flow (300 ml / min) at a heating rate of 5 °F / min from 400 °F to 900 °F and held at 900 °F for 30 minutes. Finally, the catalyst was cooled to 800 °F to initiate the sulfidation reaction.

[0055] The feed applied to the sulfidation reaction was anhydrous n-octane containing 200 ppm sulfur (as dimethyl disulfide). The sulfidation was carried out at 800°F and atmospheric pressure for 60 minutes. The flow rates of H2 and the liquid feed were 30 ml / min and 0.43 ml / min, respectively. After sulfidation, the catalyst was heated in H2 flow (300 ml / min) from 800°F to 900°F within a few minutes, and then heated at 900°F for another 30 minutes to remove excess sulfur species stored in the catalyst pores and / or surface. Finally, the catalyst was heated or cooled to a preset reaction temperature (e.g., 850°F or 950°F) within 2 hours in the same H2 flow (300 ml / min) to prepare for the catalytic naphtha reforming test of Example 6.

[0056] Example 6 Catalytic naphtha reforming test procedure

[0057] After the sulfiding procedure described in Example 5, a catalytic naphtha reforming reaction was carried out as described below.

[0058] As described in Example 5, the catalyst was heated or cooled to a preset reaction temperature (950°F for Example 8) in the same H flow (300 ml / min) within 2 hours to prepare for the start of the catalytic naphtha reforming test of this example. Simultaneously, the reactor system was pressurized to a preset pressure (150 psig for Example 8). Meanwhile, the H flow was adjusted to a preset rate (14 ml / min for Example 8). The feed rate was 1.55 ml / hr (for Example 8).

[0059] In the following examples, catalytic naphtha reforming experiments were conducted using the naphtha feed described in Example 7 at a hydrocarbon WHSV of 2.2 and a hydrogen to hydrocarbon molar ratio of 3.0.

[0060] Example 7 Catalytic naphtha reforming test feed

[0061] The GC analysis data of the feed used in the catalytic naphtha reforming test in this invention is shown in Table 5, along with the GC results of Example 8 for the catalytic naphtha reforming test product with the catalyst described in Example 5. The GC data was obtained by online analysis.

[0062] Example 8 Catalytic naphtha reforming test products

[0063] The GC analysis data for the feed of Example 7 used in the catalytic naphtha reforming test is shown in Table 5, along with the results of this example for that catalytic naphtha reforming test product with the catalyst described in Example 5. The catalytic naphtha reforming experiments were conducted at 950°F, 150 psig, hydrocarbon WHSV of 2.2, and a hydrogen to hydrocarbon molar ratio of 3.0. [Table 5]

[0064] The products in Table 5 show an increase in aromatics and octane gasoline. Boron-SSZ-41 successfully reformed the feedstock of Example 7.

[0065] As used in this disclosure, the words "comprises" or "comprising" are intended as open-ended transitions to mean the inclusion of the specified elements, but not necessarily the exclusion of other unspecified elements. The phrases "consist essentially of" or "consisting essentially of" are intended to mean the exclusion of other elements, whatever their essential significance to the composition. The phrases "consisting of" or "consists of" are intended as transitions to mean the exclusion of everything other than the recited elements, except for only trace amounts of impurities.

[0066] All patents and publications referenced herein are incorporated by reference to the extent not inconsistent herewith. It will be understood that certain of the above-described structures, functions, and operations of the above-described embodiments are not necessary to practice the present invention, but are included in the description merely to complete the exemplary embodiment(s). In addition, it will be understood that certain structures, functions, and operations set forth in the above-referenced patents and publications can be practiced in conjunction with the present invention, but are not essential to its practice. It will therefore be understood that the present invention may 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. The following peaks in the as-synthesized form: 【Table 1】 and having boron in the framework.

2. Molar relationships: B ２ O ３ :(n)(SiO ２ ) wherein n is ≧10.

2. The molecular sieve of claim 1 having a composition comprising:

3. Molar relationships: B ２ O ３ :(n)(SiO ２ ) wherein n is ≧15.

2. The molecular sieve of claim 1 having a composition comprising:

4. 3. The molecular sieve of claim 2, wherein n is in the range of about 15 to 20.

5. The molar relationship below: 【Table 2】 2. The molecular sieve of claim 1, having a chemical composition comprising: wherein Q comprises 1,1'-(1,4-butanediyl)bis[4-aza-1-azoniabicyclo[2.2.2]octane] dication.

6. The molar relationship below: 【Table 3】 6. The molecular sieve of claim 5, having a chemical composition comprising: wherein Q comprises 1,1'-(1,4-butanediyl)bis[4-aza-1-azoniabicyclo[2.2.2]octane] dication.

7. At least the following peaks in the calcined form: 【Table 4】 2. The molecular sieve of claim 1, having boron in the framework.

8. A method for synthesizing a boron molecular sieve having an SSZ-41 framework structure, comprising: （１） (a) a source of silicon; (b) a source of zinc; (c) a structure directing agent (Q) comprising 1,1′-(1,4-butanediyl)bis[4-aza-1-azoniabicyclo[2.2.2]octane] dication; (d) a source of boron; (e) a source of hydroxide ions; (f) water; and (g) Seed forming a reaction mixture comprising: (2) subjecting the reaction mixture to crystallization conditions sufficient to form crystals of the boron molecular sieve; A method comprising:

9. 9. The method of claim 8, wherein the source of silicon is aluminum-free.

10. 9. The method of claim 8, wherein the source of silicon comprises a FAU framework zeolite.

11. 9. The method of claim 8, wherein the reaction mixture has the following composition in terms of molar ratios: 【Table 5】

12. 9. The method of claim 8, wherein the reaction mixture has the following composition in terms of molar ratios: 【Table 6】

13. 11. The method of claim 10, wherein the FAU framework zeolite is zeolite Y.

14. 9. The method of claim 8, wherein the source of zinc comprises a zinc salt of an organic or inorganic acid, a zinc-exchanged FAU framework zeolite, or any combination thereof.

15. 9. The method of claim 8, wherein the seeds comprise a molecular sieve having a framework structure of SSZ-41.

16. The reaction mixture is ２ 9. The method of claim 8, further comprising 0.1 to 20% by weight of seeds based on the total weight of the mixture.

17. 9. The method of claim 8, wherein the crystallization conditions comprise heating the reaction mixture under autogenous pressure at a temperature in the range of 100° C. to 200° C. for a time period of 1 day to 14 days.

18. 1. A method for converting a feedstock comprising organic compounds into conversion products, comprising: (i) contacting the feedstock with a catalyst under organic compound conversion conditions to produce an effluent containing conversion products, wherein the catalyst comprises a boron zincosilicate molecular sieve having a framework structure of SSZ-41; (ii) recovering the conversion product from the eluate; A method comprising:

19. 10. A molecular sieve prepared by the method of claim 9.

20. 13. A molecular sieve prepared by the method of claim 12.

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