Method for manufacturing BEA zeolite catalyst for glucose conversion reaction and catalyst manufactured thereby

Abstract

The present invention relates to a method for manufacturing a BEA zeolite catalyst for glucose conversion reaction and a catalyst manufactured thereby and, more specifically, to a method for manufacturing a cobalt, nickel, and / or zinc silicate BEA zeolite catalyst by single-step structural conversion of borosilicate MWW zeolite.

Description

Method for producing BEA zeolite catalyst for glucose conversion reaction and catalyst produced thereby

[0001] <Technology>

[0002] The present invention relates to a method for producing a BEA zeolite catalyst for a glucose conversion reaction and a catalyst produced thereby, and more particularly, to a method for producing a cobalt, nickel, zinc silicate BEA zeolite catalyst by a single-step structural conversion of a borosilicate MWW zeolite.

[0003] <National Research and Development Project Supporting This Invention>

[0004] This patent application is the result of a basic research support project conducted with support from the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (Project No. 2022R1F1A1065523).

[0005] Since the discovery of natural stilbite (framework type STI) by the Swedish mineralogist Cronstedt in 1756, zeolites have been used as heterogeneous catalysts, solid adsorbents, and catalyst supports due to their excellent unique properties such as large surface area and porosity, and excellent hydrothermal stability. The physicochemical properties of zeolites can be controlled by substituting different framework atoms in the tetrahedral (T) coordination sites of the zeolite structure with phosphorus and transition metals to form aluminophosphates (AlPO), silicoaluminophosphates (SAPO), metalloaluminophosphates (MAPO), and metallosilicoaluminophosphates (MAPSO). In fact, metallosilicates and metalloaluminosilicates have been proposed as excellent catalysts in various industrial fields because the metal heteroatoms present in the zeolite structure not only exhibit excellent stability and catalytic activity, but also exhibit product form selectivity. For example, titanosilicates with MFI, BEA, and MWW structures have been successfully applied as efficient catalysts for oxidation reactions such as ammonia oxidation, epoxidation, and hydroxylation. Stannosilicate BEA (Sn-BEA) is evaluated as a favorable Lewis acid catalyst for biochemical reactions such as the conversion of glucose to 5-(hydroxymethyl)furfural (5-HMF).

[0006] In general, metallosilicates can be prepared by two synthetic routes. One route is the top-down replacement of heterometal atoms by acid and / or base treatment to remove existing framework atoms (Figure 1a). The other is the bottom-up hydrothermal synthesis of tetrahedrally coordinated metallosilicates via a conventional crystallization step using a metal precursor solution (Figure 1b). In many cases, materials synthesized using the latter method exhibit higher structural stability and catalytic activity than those synthesized using the former. Yang et al. reported excellent stability of framework Fe species in bottom-up-synthesized MFI-type iron silicate zeolites, which were not reduced at 600°C in a H2 atmosphere, demonstrating excellent activity in ethane dehydrogenation. Fan et al. synthesized TS-1(MFI) with abundant framework Ti species without the formation of octahedrally coordinated framework Ti using a (NH4)2CO3 precursor, as determined by the UV absorption peak below 260 nm. Furthermore, this catalyst demonstrated excellent performance in the oxidation of various reactants, such as linear alkenes and alkanes, alcohols, styrene, and benzene. However, the bottom-up synthesis of metallosilicates has not been widely used due to the rate mismatch between crystallization and metal substitution, unsuitable TOT bond lengths and angles, and the proneness to the formation of extra-framework metal species and aggregated metal oxides. Furthermore, the formation of metallosilicates through conventional hydrothermal bottom-up synthesis can result in prolonged crystallization times due to factors such as slow diffusion, complex chemical reactions, and nucleation processes. For example, the synthesis of Sn-BEA through conventional hydrothermal crystallization takes up to approximately 40 days, as reported in the literature.

[0007] To overcome the limitations of the bottom-up synthesis of metallosilicates mentioned above, a hydrothermal interzeolite transformation method has been proposed. Interzeolite transformation involves decomposing a parent zeolite into its common building blocks (CBUs) with the daughter zeolite, which are then reassembled into daughter zeolites with similar but different structures (Fig. 1c). The major advantage of this synthetic strategy is that it can produce somewhat predictable daughter phases in a much shorter time period than conventional hydrothermal synthesis. To date, some synthetic results for obtaining metallosilicates via the interzeolite transformation method have been reported. Lu et al. reported the interzeolite transformation into a hierarchical Ti-BEA zeolite with uniform mesopores, as well as the synthesis of Sn-BEA with a high Sn content (2.4 wt%) using steam-assisted crystallization without the addition of a fluorinating agent. A nonsolvent inter-zeolite structural conversion method from Ti-MWW to Ti-BEA has been developed to reduce the synthesis time based on the same CBUs, such as 4-, 5-, and 6-rings, between the MWW and BEA structures. Meanwhile, to the best of our knowledge, inter-zeolite structural conversion methods have only been investigated, involving metal incorporation from a dealuminate matrix with abundant defects formed by acid treatment, or between parent and daughter zeolites with identical framework atoms. If the preparation of the parent metallosilicate and / or the acid treatment step can be omitted, the synthesis time and cost can be reduced, allowing for the preparation of a wider variety of metallosilicates in a much more environmentally friendly and economical manner.

[0008] In this invention, the inventors synthesized Co, Ni, and Zn-containing BEA-structured metallosilicates through a single-step interzeolite structural transition of borosilicate MWW (B-MWW) using respective metal precursor solutions (Fig. 1d). Co, Ni, and Zn are three representative transition metals used as catalysts in various applications. Co is used in Fischer-Tropsch synthesis and reforming reactions, Ni is used in CO2 reforming of steam and methane, CO2 methanation, and ammonia decomposition, and Zn is used in industrial organic synthesis and zinc-air batteries. Unlike conventional interzeolite structural transitions that occur without compositional change, BEA-type zeolites substituted with the three transition metals are compared in terms of structural transformation and metal incorporation kinetics, framework metal coordination environments, Lewis acidity during interzeolite structural transitions, and Lewis acid catalytic activity depending on the type of heteroatom species.

[0009] In order to achieve the above object, the present invention provides a method for preparing a BEA zeolite catalyst, comprising the steps of: synthesizing a borosilicate MWW zeolite precursor [B-MWW(P)] or an aluminosilicate MWW zeolite precursor [Al-MWW(P)]; dissolving the B-MWW(P) or Al-MWW(P) and dealuminated siliceous BEA seeds in a transition metal hydrate aqueous solution; adding a tetraethylammonium hydroxide solution or a tetraethylammonium bromide solution to the transition metal hydrate aqueous solution; adding ammonium fluoride (NH4F) to the transition metal hydrate aqueous solution and drying it; and heating the powder to crystallize it.

[0010] The above MWW is one of the zeolite structures existing in a lamellar form, and the MWW framework structure is a three-dimensional zeolite including two independent pore systems, one of which is a pore system of two-dimensional sinusoidal 10-ring (10-MR) channels having an elliptical ring cross-section of 4.1 Å × 5.1 Å and the other is a pore system including a large 12-MR giant cage connected to the 10-MR window. A step for synthesizing a layered borosilicate MWW framework zeolite precursor [B-MWW(P)] by including boron in the framework of the three-dimensional MWW framework zeolite having such structural specificity, wherein the boron is combined in the form of Si-OB in the MWW framework.

[0011] The step of synthesizing the above MWW zeolite precursor [MWW(P)] can be synthesized using an organic structure derivative (SDA) as an example, and a three-dimensional MWW can be formed by removing the organic structure derivative and condensing it by calcination during the synthesis process, but is not limited thereto and can be synthesized by a generally known method, and a detailed description thereof is omitted herein.

[0012] The above B-MWW(P) is characterized in that the molar ratio of Si / B is 9-10, preferably 9.5.

[0013] The Si / Al molar ratio of the above Al-MWW(P) is characterized by being 12-18, preferably 15.

[0014] The above transition metal may be cobalt (Co), nickel (Ni), or zinc (Zn), and in this case, the transition metal hydrate aqueous solution may be a solution of cobalt (II) nitrate hexahydrate, nickel (II) nitrate hexahydrate, or zinc (II) nitrate hexahydrate. The concentration of the transition metal hydrate aqueous solution may be 0.005-0.1 M, and preferably 0.01 M.

[0015] The crystallization time is characterized by being 1-168 hours, and the heating temperature of the crystallization step is 150-250°C, preferably 190°C.

[0016] The above BEA zeolite catalyst manufacturing method may further include a washing step and a calcination step after the crystallization step.

[0017] The above washing step can be performed for 20-30 hours with HF or KOH solution, and the above calcination step can be performed for 5-12 hours at a temperature of 500-600°C.

[0018] According to another embodiment of the present invention, a BEA zeolite catalyst manufactured by the above BEA zeolite catalyst manufacturing method is provided.

[0019] The BEA zeolite catalyst manufactured by the above BEA zeolite catalyst manufacturing method is characterized in that the BET surface area of ​​the BEA zeolite increases as the molecular weight of the transition metal decreases.

[0020] In addition, the BEA zeolite catalyst is characterized in that it does not exhibit Bronstedt acidity but exhibits Lewis acidity, and the Lewis acidity increases in the order of Zn-BEA, Co-BEA, and Ni-BEA.

[0021] The above BEA zeolite catalyst can be a catalyst for a glucose conversion reaction, and among the Zn-BEA, Co-BEA and Ni-BEA zeolite catalysts, the Zn-BEA zeolite catalyst is characterized by a higher 5-HMF conversion yield than the Co-BEA and Ni-BEA zeolite catalysts.

[0022] The synthesis of cobalt-, nickel-, and zinc-silicate BEA zeolites (Co-BEA, Ni-BEA, and Zn-BEA) was systematically investigated via a single-step hydrothermal interzeolite transformation of borosilicate MWW (B-MWW) using respective metal precursor solutions. All three metallosilicates exhibited distinct BEA structures containing stable framework metal species, but their structural transformation and metal substitution kinetics differed depending on the metal type. Crystallization of Co-BEA and Ni-BEA was completed within 2 days, whereas crystallization of Zn-BEA continued after 7 days. Independent of the crystallization kinetics, the incorporation rate of Co into the BEA structure was slower than that of the other two metals. The characteristics of the BEA structures depending on the type of framework heteroatoms were further supported by density functional theory calculations (DFT). Despite similar metal contents (approximately 3 wt%), the Lewis acidities of fully crystallized Co-, Ni-, and Zn-BEA varied depending on the type of framework metal. These three metallosilicates exhibited excellent catalytic activity for glucose conversion as Lewis acid catalysts, and the catalytic results were attributed to the unique properties of the catalysts determined during the synthesis stage.

[0023] Figure 1 is a schematic diagram showing (a) top-down synthesis of metallosilicates using acid treatment and / or metal precursor solutions, (b) bottom-up synthesis of metallosilicates, (c) inter-zeolite structural conversion into metallosilicates, and (d) single-step inter-zeolite structural conversion using metal precursor solutions in this study.

[0024] Figure 2 is a graph showing the crystallization: powder XRD patterns of the solid products obtained from the crystallization of (a) Co-BEA (batch 1), (b) Ni-BEA (batch 2), and (c) Zn-BEA (batch 3), with powder XRD patterns of B-MWW and B-BEA added for comparison; curves of relative crystallinity (■: MWW, ●: BEA) and TEA+ content (▲) as a function of crystallization time for (d) batch 1, (e) batch 2, and (f) batch 3, respectively, determined from powder XRD and TGA / DTA. BET surface areas of the solid products obtained from (g) batch 1, (h) batch 2, and (i) batch 3 as a function of crystallization time. The BET surface area of ​​the parent B-MWW is shown for comparison.

[0025] Figure 3 shows the 500-1600 cm spectroscopy images of a series of solid products obtained from the crystallization of (a) Co-BEA (batch 1), (b) Ni-BEA (batch 2) and (c) Zn-BEA (batch 3) at different crystallization times. -1 Normalized IR spectra of the structural domain are shown, and the IR spectra of the parent B-MWW and B-BEA are added for comparison. (df) TEM and (g-i) STEM-EDS images of fully zeolite structure-converted (d,g) Co-, (e,h) Ni- and (f,i) Zn-BEA obtained after crystallization times of 48, 24 and 168 h in batches 1-3 are shown.

[0026] Figure 4 shows the framework-metal (■) and boron (●) contents as a function of crystallization time and the Si / Me ratio curves (▲) for solid products obtained from (a) batch 1 (Co-BEA), (b) batch 2 (Ni-BEA) and (c) batch 3 (Zn-BEA) as determined by ICP elemental analysis, with elemental analysis data for the parent B-MWW added for comparison. UV-DRS spectra for a series of solid products obtained from (d) batch 1 (Co-BEA), (e) batch 2 (Ni-BEA) and (f) batch 3 (Zn-BEA) for different crystallization times, UV-DRS spectra are stacked at 0.5 intervals about the y-axis. Co, Ni and Zn 2p XPS spectra of fully zeolite-interstructured (g) Co-, (h) Ni- and (i) Zn-BEAs obtained after crystallization times of 48, 24 and 168 h in batches 1-3 are shown; respectively: experimental (top); simulated (middle); and resolved constituent peaks (bottom).

[0027] Figure 5 is (a,b) (ac) Co 2+ , (d)Ni 2+ and (e) Zn 2+ General and (ce) enlarged views of the most stable DFT-optimized structures of the atom-substituted polymorph A zeolite BEA structure: Si (red); O (blue); Co (violet); Ni (cyan); Zn (orange); H (white).

[0028] Figure 6 shows the IR spectra after pyridine adsorption at 100°C for fully zeolite-interconverted Co-, Ni-, and Zn-BEA catalysts obtained after 48, 24, and 168 h of crystallization in batches 1-3, (a) IR spectra in the hydroxyl region, (c) glucose conversion over Co-, Ni-, and Zn-BEA catalysts, and (d) yields of fructose (closed) and 5-HMF (open). Regions are presented using ball-and-stick and line styles, respectively, which were relaxed and fixed during optimization. Distances between substituted metals and adjacent oxygen atoms are indicated (Å).

[0029] Hereinafter, the present invention will be described in more detail through examples and experimental examples. However, these examples are intended only to aid understanding of the present invention and are not intended to limit the scope of the present invention in any way.

[0030]

[0031] <Example>

[0032] 1. Synthesis

[0033] The borosilicate MWW precursor (B-MWW(P)) with Si / B = 9.5 (molar ratio) was synthesized according to a previously reported procedure using hexamethyleneimine (HMI, 99%, Aldrich) as an organic structure-directing agent (SDA). For comparison, aluminosilicate (Al-MWW(P), Si / Al = 15) and gallosilicate MWW precursors (Ga-MWW(P), Si / Ga = 10) were also synthesized by a similar procedure to B-MWW(P) using sodium aluminate (99%, Kanto) and gallium nitrate (100%, Strem) instead of boric acid (99.5%, Junsei), respectively. The synthetic molar compositions of B-, Al-, and Ga-MWW(P) were 2.0HMI·0.6Na2O·1.0B2O3·3.0SiO2·57H2O, 15HMI·1.7Na2O·1.0A2O3·30SiO2·1350H2O, and 10HMI·2.0Na2O·1.0Ga2O3·20SiO2·900H2O. B-MWW(P) was prepared using 1 M cobalt(II) nitrate hexahydrate (98%, Junsei), nickel(II) nitrate hexahydrate (98%, Samchun), and zinc(II) nitrate hexahydrate (98%, Samchun) solutions, respectively, according to the procedures reported in our previous study. The synthetic molar composition of Me-MWW was 4.0SiO2·1.0MeO·9.4H2O. All synthesized MWWs were calcined at 550 °C for 8 h to remove the organic SDA trapped within the structure.

[0034] The single-step interzeolite structural transformation to Me-BEA (Me = Co, Ni, and Zn) followed a modified procedure different from that reported in previous work. A typical synthesis in this study was as follows: Calcined B-MWW powders and dealuminate siliceous BEA seeds were dissolved in 0.01 M cobalt(II) nitrate hexahydrate, nickel(II) nitrate hexahydrate, or zinc(II) nitrate hexahydrate solutions. The dealuminate BEA was prepared by treating with 13 M HNO3 solution at 100 °C for 24 h. Subsequently, tetraethylammonium hydroxide solution (TEAOH, 35%, Aldrich) or TEABr (98%, Aldrich) was added to the mixture. After stirring for 5 min, ammonium fluoride (NH4F, 98%, Junsei) was added and stirred until homogeneous, and then the mixture was dried overnight at 80°C under atmospheric pressure. If necessary, the drying step was omitted during the synthesis. The final molar composition of the synthetic mixture was (0 or 1)SiO2(0, 0.3, or 0.9)TEA with 0 or 10 wt% dealuminate BEA seeds relative to SiO2 of B-MWW. +· 0.5NH4F(0.03 or 0.3)Me. The dried synthetic powder, labeled 0 h, was transferred to a 23 mL Teflon-lined stainless steel autoclave and heated at 190°C for various crystallization times (1 h to 28 days) under static conditions. In a typical synthesis, the Teflon lining was routinely washed with dilute HF and KOH solutions for 24 h each. After structural transformation between zeolites, the solid product was thoroughly washed with deionized (DI) water, recovered by filtration, and dried at room temperature. The synthesized product was calcined at 550°C for 8 h to remove the organic SDA. The detailed molar compositions of each synthetic batch are summarized in [Table 1].

[0035] batchno.synthesis mixtureproductmolar compositionmetal precursor sol.siliceous BEAseed (wt.%)pHB-MWWTEAOHNH4Fmetalconc. (M)110.30.5Co0.01109.55BEA210.30.5Ni0.01109.68BEA310.30.5Zn0.01109.48BEA410.30.5Co0.0110-BEA510.30.5Ni0.0110-BEA610.30.5Zn0.0110-BEA710.30.5Co0.0110-MWW + BEA810.30.5Ni0.0110-BEA + MWW910.30.5Zn0.0110-MWW + BEA1000.30.5Co0.0110-Am. + BEA1100.30.5Ni0.0110-Ni-Si1200.30.5Zn0.0110-BEA + Ni-Si1310.30.5Co0.010-BEA + MWW1410.30.5Ni0.010-BEA + MWW1510.30.5Zn0.010-Am. + MWW16100.5Co0.0110-Am. + MWW17100.5Ni0.0110-Am. + MWW18100.5Zn0.0110-MWW1910.30.5Co0.0110-Am. + MWW2010.30.5Ni0.0110-Am. + MWW2110.30.5Zn0.0110-Am. + MWW2210.30.5Ni0.1107.62Ni-Si2310.90.5Ni0.011013.52BEA2410.30.5Ni0.0110-Am.

[0036]

[0037] If necessary, the protonated form of Me-BEA (H-Me-BEA) was prepared by repeated ion exchange with a 1 M ammonium nitrate (98%, Aldrich) solution at 80°C for 8 h, followed by calcination at 550°C for 2 h. For comparison, calcined Al- and Ga-MWW were used as silica sources instead of B-MWW. In addition, B-, Co-, Ni-, and Zn-BEA were prepared from structural transformations between zeolites, B-, Co-, Ni-, and Zn-MWW, respectively, at 190°C for 12 h according to the following procedure.

[0038]

[0039] 2. Results

[0040] 1) Inter-zeolite structural conversion of B-MWW to Me-BEA

[0041] Figures 2a–c show powder XRD patterns of the solid products obtained from the synthesis of Co-BEA (batch 1), Ni-BEA (batch 2), and Zn-BEA (batch 3), respectively, as a function of crystallization time. Representative synthetic conditions and results are also summarized in Table 1. The solid sample obtained at 0 h exhibited only the characteristic pattern of MWW without peaks of the BEA structure, which was attributed to the relatively small amount of BEA seeds compared to B-MWW and / or the dissolution of BEA seeds during the preparation of the synthetic gel. In all three batches, as crystallization progressed, the XRD patterns for the parent MWW gradually disappeared and the BEA phase gradually increased. Notably, under the same synthetic conditions, the crystallization rate varied depending on the metal precursor solution used. As shown in Figures 2d–f, complete structural transformation occurred within 48, 24, and 168 h for Co-, Ni-, and Zn-BEA, respectively. Interestingly, the crystallization kinetics of the direct transformation from B-MWW to Ni-BEA using nickel nitrate solution in this study (Fig. 1d) was slower than the inter-zeolite structural transformation from Ni-MWW to Ni-BEA reported in a previous study (Fig. 1b). In the latter case, Ni-BEA was almost completely crystallized in 2 h. This indicates that the structural transformation of zeolites and the substitution of framework atoms occur separately during the crystallization process. Meanwhile, the volume expansion of the zeolite lattice due to the substitution of larger framework atoms (Co > Ni > Zn > B) was also observed through the shift of the X-ray diffraction peak to lower angles (22.42°, 22.44°, and 22.54° for Co-, Ni-, and Zn-BEA, respectively) compared to B-BEA (22.57°), which corresponds to the (302) plane of the BEA structure. Hereinafter, unless otherwise specified, fully crystallized Co-, Ni- and Zn-BEA are solid products obtained from batches 1 to 3 after crystallization at 190°C for 48, 24 and 168 hours, respectively.

[0042] Also, Figures 2d-f show TEA of the solid product as a function of crystallization time determined via TGA / DTA. + The organic content changes are shown. In particular, the organic content profiles of Co-, Ni-, and Zn-BEA with respect to crystallization time (▲) are consistent with the XRD-based crystallization curves (●) of the BEA phase. In the initial stage of interzeolite structural transformation (1 h), the organic contents of the solid products are about 4, 7, and 2 wt% for batches 1-3, respectively, which is proportional to the crystallization rate. However, the organic contents of fully crystallized Co-, Ni-, and Zn-BEA are about 15, 11, and 9 wt%, respectively, which is inversely proportional to the molecular weight of the metal species. In contrast to the crystallinity change of Me-BEA, the MWW phase decreased steadily during the interzeolite structural transformation of synthetic batches 1-3. These results correspond to the difference in the crystal morphology of Me-BEA and B-MWW, which are irregularly shaped crystals and platelet-like masses, respectively.

[0043] The decrease in MWW phase and the increase in BEA phase were further confirmed by the BET surface area changes determined from N2 sorption isotherms versus crystallization time (Fig. 2g-i and Table 2). The increase in the external surface area of ​​the solid product in the early stages of the structural transition between zeolites indicates the exfoliation and decomposition of the B-MWW crystals. This correlates with the results of a previous study, namely the synthesis of metal-silicate exfoliated MWW layers by simple hydrothermal treatment using metal nitrate precursors. Interestingly, during each Me-BEA crystallization, the external surface area of ​​the solid product was maximized when the most intense X-ray peak for BEA started to appear at about 2θ = 22.5° (Fig. 2a-c). This arises from the interparticle void volume between the decomposed subunits. In contrast, for Co, Ni, and Zn-BEA, the external surface area was maximized after 3 h (97 m 2 g -1 ), 2 hours (127m) 2 g -1 ) and 12 hours (73m 2 g -1) showed a minimal micropore area and increased again as crystallization was prolonged. This indicates the reassembly of the disassembled subunits of B-MWW to crystallize the BEA phase. After complete crystallization, Me-BEA showed a total surface area in the following order: Co-BEA (420 m 2 g -1 ) > Ni-BEA(394 m 2 g -1 ) > Zn-BEA(293 m 2 g -1 ) is also inversely proportional to the molecular weight of the metal used, as explained above. The lowest total surface area of ​​Zn-BEA can be attributed to the highest molecular weight of Zn, since the metal content of fully crystallized Me-BEA is similar (i.e., about 3 wt% in Table 2), resulting in an underestimated specific surface area and / or a non-fully crystallized Zn-BEA structure.

[0044] productcrystallizationtime (h)BET surface area (m 2 g -1 )ICP elemental analysis acid concentration (μmol g -1 )totalExternalmicroporeMe (wt.%)B (wt.%)Si / MeBrønstedLewisB-MWW-4772545201.89.50n.d.batch 1(Co-BEA)1412533590.81.0120.5--2418723462.00.849.5--3425973282.50.738.9--640635 3712.70.637.4--12380423382.80.536.9--24420253952.60.540.2--48420194012.40.543.00 (0)129 (80)batch 2(Ni-BEA)1456903662.60.839.6--24741273472.80.738.6--34661153512.80.63 9.8--6421583633.00.538.3--12403273763.10.439.4--24394213733.10.441.90 (0)302 (194)batch 3(Zn-BEA)1402243782.60.744.6--12301732283.10.445.0--24284642203.10.345.9--4827655 2203.20.447.2--72256482083.40.448.3--120277272503.30.448.3--168293222703.30.447.80 (0)118 (102)

[0045] Figures 3a-c show the 500-1600 cm spectroscopy of a series of solid products synthesized by inter-zeolite structural transformations from B-MWW to Co-, Ni-, and Zn-BEA. -1 The IR spectra of the structural region are shown. All solids obtained after 1 hour of crystallization showed the following peaks: 569, 611, 809, 1080, 1183, and 1243 cm -1 The characteristic IR bands of the MWW structure were observed at 937 and 1403 cm -1 The IR bands are assigned to the four- and three-coordinate framework B species. Depending on the crystallization time, it is difficult to quantify the IR peaks of the Periodic Building Unit (PBU) of the BEA structure, i.e., the six-ring and five-ring, but they are located at 525 and 573 cm, respectively. -1After different crystallization times (3, 2, and 12 h for Co-, Ni-, and Zn-BEA, respectively), the peaks were clearly observed. These results are in good agreement with the results of powder XRD and N2 adsorption experiments. Finally, the fully crystallized Me-BEA sample showed no characteristic peaks at 1060 cm without the characteristic peaks corresponding to MWW and framework B species. -1 In the BEA structure, the IR bands for PBU and OTO asymmetric vibrations were clearly shown, indicating a complete inter-zeolite structural transition and the substitution of metal species for B species within the structure. In particular, each final Me-BEA product had an IR band of about 1020 cm -1 IR peaks assigned to Si-O-Co, Si-O-Ni, and Si-O-Zn were observed in the B-MWW, indicating that Co, Ni, and Zn atoms were introduced into the T-site during the direct zeolite structural transformation of B-MWW. Highly dispersed framework heteroatoms were confirmed by (S)TEM-EDS images (Fig. 3d–i). All EDS elemental mappings of the fully crystallized Me-BEA samples resulted in approximately 2–3 wt% of replacement metal contents, which were similar to the values ​​determined by ICP elemental analysis (Table 2). Although the same hydrothermal temperature (190 °C) and crystallization time (12 h) were applied, the Zn and Ni contents of the interconverted Zn- and Ni-BEA from B-MWW (3.3 and 3.1 wt%, Table 2) were lower than those of Me-BEA from Me-MWW (4.1 and 7.3 wt%) reported in our previous work. This indicates the impediment of framework atom replacement by the simultaneous structural transformation.

[0046] Figures 4a-c show the elemental composition changes of the solid products obtained from batches 1-3 as a function of crystallization time. The values ​​are also summarized in Table 2. In all three cases, a rapid decrease in the B content was observed from the beginning of the structural transformation between zeolites, and the decrease rates were similar. The weakly acidic (pH < 6) metal nitrate precursor solution with a concentration of 0.01 M could induce the leaching of B atoms from the borosilicate framework even in the preparation of synthetic gels. Simultaneously, the metal contents of the solid products increased rapidly, but the rate of increase varied depending on the type of metal species. The Co content of the solid product obtained after 1 h of crystallization was only 0.8 wt%, whereas that of Ni and Zn was 2.6 wt% at the same time. In contrast to the lowest structural transformation tendency of Zn-BEA among the three cases, the metal substitution rate was the lowest in Co-BEA. This is because Co was more abundant than other metal cations in the aqueous synthetic gel, as can be seen in the potential-pH equilibrium diagram. 2+ This can be explained by the higher stability of the ions. In addition, during the crystallization process, larger hydrated Co cations (i.e., Co(H2O)6) than Ni and Zn 2+ ) can induce higher diffusion restrictions on access to the vacancies created by the extraction of B from the synthetic solution. These results demonstrate that structural transformation and substitution of metal species, although occurring simultaneously, proceed through separate kinetic processes. Although the Co content of the fully crystallized Co-BEA was slightly lower than that of the other two Me-BEAs, all three Me-BEAs showed similar metal contents of approximately 3 wt% (Table 2).

[0047] Figures 4d-f show the UV-DRS spectra of the solid products obtained from the crystallization of Co-, Ni-, and Zn-BEA. Intense UV absorption bands below 250 nm were observed in all cases before crystallization (0 h), due to the formation of metal hydroxides and / or metal silicates formed from the decomposition of the corresponding metal precursors and / or the dissolution of the parent B-MWW under alkaline conditions, respectively. Since the XRD patterns for the 0 h samples only show the MWW structure (Figures 2a-c), the 0 h samples appear to be mainly composed of the still undecomposed parent B-MWW and amorphous metal hydroxides. In particular, the UV absorption band intensities of the samples obtained from batches 1-0 h were lower than those of the other two 0 h samples from batches 2 and 3, which is consistent with the above-mentioned Co 2+This can be explained by the higher stability of the ions (Fig. 4a-c). The intensity of the UV absorption band observed in the sample before crystallization (0 h) decreased significantly upon crystallization at 190°C due to the further conversion of metal hydroxides to metal silicates. When the zeolite was converted to Co-BEA (Fig. 4d), the increase in the UV absorption band centered below 260 nm, corresponding to the framework Co species, was significant during the initial period of crystallization (1–3 h), while the increase in the band was observed later and reached a maximum at 12 h. This correlates well with the change in Co content as a function of crystallization time shown in Fig. 4a. A slight decrease in the band intensity was observed at 6 h, which is probably due to the strongest transition state in the structural transformation from MWW to BEA at this crystallization time, as revealed by powder XRD and N2 adsorption measurements. A series of solid products for Ni-BEA crystallization exhibited nearly similar intensities in the UV absorption band at approximately 210 nm (Fig. 4e), indicating rapid substitution of framework Ni species. This is also associated with the rapid increase in Ni content in the solid products during the crystallization of Ni-BEA (Fig. 4b). For Zn-BEA, the UV absorption band at approximately 200 nm was dominant after 1 h of crystallization, while the band at approximately 260 nm steadily increased after 12 h of crystallization (Fig. 4f). Since the Zn species in ZnO have a UV absorption band at a higher wavelength, approximately 300 nm, the UV absorption band appearing in the 200–260 nm range should originate from the injected framework Zn species.

[0048] In particular, all fully crystallized Co-, Ni-, and Zn-BEAs exhibited three resolved UV absorption bands at different ratios: <210 nm, about 260 nm, and >300 nm. As described above, the UV absorption band >300 nm can be assigned to the metal oxide.

[0049] The other two UV absorption bands at lower wavelengths, known as framework metal species, can be explained in two ways: (i) the wavelengths are O 2- is inversely proportional to the energy required for charge transfer from the framework metal species to the Me. Therefore, these two bands are located at low wavelengths (< 210 nm) and high wavelengths (approximately 260 nm), respectively. δ+ (δ = 3 or 4) and Me 2+ can be designated as [Ar]3d. However, Zn is [Ar]3d 10 4s 2 It has an electronic configuration and therefore a filled 3d 10 Zn because the electrons in the shell do not participate in chemical reactions δ+ It is not convincing that Zn-BEA exists in the actual chemical environment. Nevertheless, some studies have shown that Zn exists only in the presence of superelectrophilic ligands such as AuF6, which have an electron affinity of 8.4 eV, which is much higher than that of oxygen (1.5 eV). δ+ reported the possibility of. Therefore, the presence of multivalent Zn atoms in Zn-BEA can be ruled out. However, although multivalent Co and Ni can be formed in Co- and Ni-BEA, respectively, since Me(NO3)2 reagent was used in the synthesis and their UV absorption bands appear at wavelengths similar to the UV spectrum of Zn-BEA, these metal species are also divalent cations (Me 2+ ) are believed to have. (ii) The intensity of the UV absorption band at about 260 nm of as-made Co-BEA decreased, whereas the intensity of the UV band at < 210 nm increased with increasing crystallization time. Similar trends were observed for Ni- and Zn-BEA crystallization. It was also reported that the intensity of the UV absorption band at 255 nm decreased during the crystallization of VET-type zincosilicate due to the formation of Si-O-Zn bonds. Based on these results, the UV absorption band at about 260 nm is believed to be due to the formation of incompletely formed framework Me. 2+It can be suggested that the species, i.e. O-Me-OH (intermediate Me, Fig. 1d-iii), means the fully formed framework Me, and the band below 210 nm indicates the fully formed framework Me. 2+ The species, i.e., O-Me-O (isolated Me, Fig. 1d-iv), is represented. After calcination at high temperatures, the intermediate Me-OH can be converted to isolated Me-O by further condensation, which is most evident in Ni-BEA (Fig. 4e). As a result, the proportion of isolated Me in calcined Me-BEA was in the following order: Ni-BEA (82%) > Co-BEA (60%) > Zn-BEA (13%), and the intermediate Me-OH was in the reverse order.

[0050] Figures 4g-i show the Co, Ni, and Zn 2p XPS spectra of three fully crystallized Me-BEA samples. The Me 2p XPS spectrum can be divided into two spin-orbit doublets, namely, Co 2p 1 / 2 (785.0-813.0 eV) and 2p 3 / 2 (775.0-784.0 eV), Ni 2p 1 / 2 (872.0-877.0 eV) and 2p 3 / 2 (850.0-854.0 eV) and Zn 2p 1 / 2 (1045.1-1045.8 eV) and 2p 3 / 2 (1022.0-1022.7 eV). Co and Ni 2p XPS spectra have peaks of shake-up satellites at 786.8 and 804.6 eV for Co and 862.0 and 880.0 eV for Ni. Me 2p 3 / 2 The XPS spectrum can be separated into two or three peaks. Co- and Zn-BEA exhibit peaks at the lowest binding energy, which are attributed to oxidized Co and Zn species, while in Ni-BEA, almost no peaks for NiO are observed. However, two Me 2p peaks are present at the highest or second highest binding energy. 3 / 2The peaks should come from framework metal species. These two peaks can be considered as isolated and intermediate metal species, respectively, because higher binding energies indicate stronger interactions with framework oxygen atoms. In addition, the ratio of two or three XPS peaks appearing from high to low binding energies is similar to the ratio of UV absorption bands from low to high wavelengths. Consequently, among the three metal-containing BEAs, Zn-BEA exhibited the lowest isolated Me ratio but the highest intermediate Me ratio, which is related to the slowest crystallization rate of Zn-BEA (Fig. 2f).

[0051] Figure 5 shows the most stable DFT optimized structure of polymorph A of BEA zeolite in which two Co, Ni and Zn atoms are substituted at the Si8 site. Co 2+ and Ni 2+ In the case of Zn, two protons are attached to the O4 and O17 atoms, whereas 2+ The case is characterized by two protons connecting the O6 and O10 atoms. Their E sub The value is Co(58.4 kJ mol -1 ) > Ni(13.8 kJ mol -1 ) > Zn(-0.5 kJ mol -1 ) was estimated in the order of . As with the most stable structure, the average E according to the different framework metal species sub The value is Co(85.9 kJ mol -1 ) > Ni(41.7 kJ mol -1 ) > Zn(22.2 kJ mol -1) showed the following order: Zn is the most stable metal species existing as isolated Me among the interzeolite structurally transformed Me-BEA. However, these calculated results are different from the experimental results described above. To explain these results more clearly, another Me-BEA was prepared by interzeolite structurally transformed Me-MWW instead of B-MWW and then subjected to UV-DRS analysis. The structural transformation of B-MWW using metal precursor solutions and the other three Me-BEAs all produced BEA structures even after 12 h of hydrothermal heating. Interestingly, these other Me-BEAs showed a high proportion of isolated Me species in the order Zn (88%) > Ni (82%) > Co (56%), which is consistent with the DFT results. The synthesis of Me-BEA from Me-MWW involved only structural transformation, and metal substitution already occurred during the synthesis of Me-MWW. This resulted in a much faster crystallization time of Me-BEA (less than 12 h) and sufficient stabilization of the framework metal species. Furthermore, when comparing the CO2TPD profiles of two Zn-BEAs prepared by inter-zeolite structural transformation of Zn- and B-MWW, respectively, the latter exhibited about six times higher CO2 chemisorption, which could be attributed to the higher concentration of the monodentate intermediate Zn-OH. Therefore, the overall experimental and calculated results indicate that the thermodynamically complete Zn-BEA structure was not yet formed even after 7 days of inter-zeolite structural transformation of B-MWW with Zn precursor solution. Meanwhile, the VT XRD pattern of the fully crystallized Me-BEA sample showed strong structural stability up to 800 °C. In addition, no X-ray peaks were observed for metallic Co, Ni, or Zn, which could be attributed to the stable framework metal species of the BEA structure.

[0052] Compared to more common aluminosilicate zeolites, borosilicates are known to facilitate the substitution of heteroatoms, because B has similar atomic properties to Al but a smaller atomic radius. However, in this study, Al- and Ga-MWW were also prepared to compare their structural transformation properties under the same conditions as B-MWW. Ga also has similar atomic properties to B and Al, which belong to the same group in the periodic table, and gallosilicates can generally be prepared with the same zeolite structure as aluminosilicates. Although not shown, Al- and Ga-MWW showed XRD patterns of pure MWW structures similar to B-MWW, except for the difference in relative crystallinity. In particular, when comparing the X-ray peak positions, the strongest X-ray peak corresponding to the (311) plane of the MWW structure gradually shifted to lower angles (from 26.4° for B-MWW to 26.1° for Al-MWW and 26.0° for Ga-MWW). This was due to the expansion of the lattice volume by the larger-sized framework atoms (Ga > Al > B). In addition, the characteristic IR bands for MWW were located at about 560 and 670 cm -1 was observed in all three samples, with the strongest IR band for Si-OT (T = B, Al or Ga) vibrations at 1087 cm for B-MWW. -1 , 1079 cm for Al-MWW -1 , 1073 cm for Ga-MWW -1were shifted to lower wavenumbers. These results indicate the successful synthesis of both aluminosilicate and gallosilicate MWW. As shown in Table 1, all solid products obtained by interzeolitic structural conversion of Al-MWW with Co (batch 4), Ni (batch 5), and Zn (batch 6) precursor solutions exhibited characteristic XRD patterns for the BEA structure after the same crystallization time as the respective Me-BEA from B-MWW. However, the BEA structure was not completely crystallized through the interzeolitic structural conversion of Ga-MWW even after 14 days of heating (batches 7-9). In particular, the interzeolitic structural conversion solid products of Al and Ga-MWW containing Co and Zn precursor solutions did not exhibit UV-DRS absorption bands for the metal species introduced into the framework. In contrast, the framework Al and Ga atoms of MWW were replaced by Ni species as in B-MWW. These results indicate that Ni-BEA is the most efficient product for kinetically favorable structural transitions and heteroatom substitution.

[0053] To further investigate the structural transformation and metal substitution phenomena during the zeolite structural transition from B-MWW to Me-BEA, a series of synthetic experiments were performed using B-MWW as a SiO2 source, siliceous BEA seeds, TEA+, OH-, and metal precursor solutions (batches 10-24 in Table 1) and adjusting the amount or concentration of B-MWW. As shown in the powder XRD patterns of the 0 h samples from batches 10-12, when the synthetic solutions were prepared under the same conditions as those from batches 1-3, the 0 h samples from batches 10-12 without the addition of B-MWW showed that the siliceous BEA seeds were completely dissolved only in the Ni precursor synthesis, while the BEA structure was significantly maintained in the Zn precursor samples. The UV-DRS spectrum of the Ni precursor sample (0 h) indicates Ni substitution in the structure as described above, indicating that mostly nickel silicates were formed among the products from batches 10-12 without hydrothermal heating. In particular, the dissolution of siliceous BEA seeds varied with the pH value of the Me-BEA composite gel: 9.68 (Ni-BEA) > 9.55 (Co-BEA) > 9.48 (Zn-BEA) (Table 1), which may have influenced the structural transformation rate of Me-BEA. Therefore, the solubility of siliceous BEA seeds appears to play a role in controlling the crystallization kinetics of Me-BEA.

[0054] Except for the siliceous BEA seeds (batches 13-15), the MWW phases were maintained for up to 28 days after hydrothermal treatment. In addition, BEA structures were hardly formed in the synthesis using the Zn precursor. These results indicate that the decomposed BEA seeds serve as CBUs that can accelerate the growth into BEA structures. In the absence of TEAOH (batches 16-18), no BEA structures were formed in any of the syntheses under the three metal precursors even after hydrothermal heating for 28 days, and the parent MWW structures were not dissolved in the Zn precursor synthesis. In addition, under the same conditions as in batches 1-3, three metal precursor syntheses were performed using TEABr instead of TEAOH (batches 19-21), indicating that OH acts as a mineralizer in the structural transformation between these zeolites. - The role of OH was evaluated. Similarly, all three batches did not induce crystallization even after hydrothermal heating for 28 days. Therefore, when comparing BEA seeds and TEAOH, the latter plays a more dominant role in the formation of BEA structures through structural transformation, while OH - It can be concluded that it plays a role in generating a common subunit for transformation between zeolites.

[0055] Moreover, when the concentration of Ni precursor solution was increased 10-fold (batch 22) and the amount of TEAOH was increased 3-fold (batch 23) under the same synthetic conditions as in batch 2, which resulted in complete interzeolite structural transformation from B-MWW to Ni-BEA within 24 h, the product of batch 22 showed the characteristic powder XRD pattern of nickel phyllosilicate and structural IR spectrum at 1020 cm -1While batch 23 showed enhanced peaks for Si-O-Ni, the product of batch 23 showed clear formation of BEA structure but no framework Ni species. It should be noted that the pH values ​​of these two synthetic solutions were 7.62 and 13.52 (Table 1), which were more acidic and basic than those of batch 2 (9.62). According to these results, excessive acidic conditions induced significant B extraction and Ni incorporation, whereas excessive disruption of the zeolite structure and basic conditions and organic SDA induced structural transformation into BEA rather than Ni incorporation due to the weak ability of the organic SDA to extract framework B. Therefore, appropriate acid-base conditions are an important factor in the synthesis of metallosilicates through single-step zeolite-to-zeolite structural transformation. Finally, Ni-BEA synthesis was attempted under the same conditions as batch 2 except for the drying step (batch 24). The solid product obtained after heating for 24 h did not exhibit a characteristic XRD pattern for BEA, and a UV band for NiO was prominently observed. Therefore, the initial drying step appears to be important for the rapid structural transformation of zeolites into metallosilicates.

[0056]

[0057] 2) Me-BEA as a Lewis acid catalyst

[0058] Pyridine adsorption IR spectroscopy revealed the acidic nature of the zeolite catalyst, i.e., 1540 and 1450 cm -1It can be used to analyze the Brønsted and Lewis acid sites appearing in the pyridine adsorption IR spectrum of B-MWW containing 1.8 wt% of B species showed almost no acidity (Table 2), which can be said that the B species in the structure of fully crystallized Me-BEA did not affect the catalytic results. As shown in Fig. 6a, all fully crystallized Me-BEA catalysts did not show Brønsted acidity due to the compensation of proton cations, but only Lewis acidity in the order of Ni-BEA > Co-BEA > Zn-BEA (Table 2). In H-Me-BEA, there was no Brønsted acidity due to Si-OH-Me. When the divalent metal cation is connected to the framework in a four- or three-coordinate manner, H can stabilize the framework through the negative charge and electrical bond of the divalent metal site. + There should be a compensating cation such as . However, if the framework metal atoms are bonded by connecting as many positively charged atoms as possible, there should be no compensating cation, but silanol groups (Si-OH) may exist around the heteroatoms (Fig. 1d-ii,iii). As shown in Fig. 6b, the IR spectra in the hydroxyl region show silanol groups in the order Zn-BEA > Co-BEA > Ni-BEA, which is in good agreement with the relative proportion of intermediate Me determined by UV-DRS and XPS characterization (Fig. 4d-i). These results indicate that the framework heteroatoms of Me-BEA are coordinated by the number of positively charged atoms. In addition, the Lewis acidity of Mn-doped BEA zeolites has been reported to depend on the amount of isolated mononuclear Mn species. Therefore, the order of Lewis acidity can also be explained by the difference in the amount of isolated Me in Me-BEA, i.e., Ni-BEA > Co-BEA > Zn-BEA.

[0059] The sequential catalytic conversion of glucose to fructose and 5-HMF was evaluated over three fully interconverted zeolite-based Me-BEA catalysts. This catalytic reaction is well known: glucose is isomerized to fructose at the Lewis acid site, followed by fructose dehydration at the Brønsted acid site to form 5-HMF. 5-HMF can be utilized as a feedstock for the production of biomass-derived polyethylene furandicarboxylate (PEF), a potential replacement for polyethylene terephthalate (PET). Figure 6c shows the glucose conversion over fully interconverted Co-, Ni-, and Zn-BEA. All three catalysts exhibited glucose conversions similar to those reported in the literature for Sn-BEA, and significantly higher than those obtained without a catalyst. Initial glucose conversion followed the order Ni-BEA > Co-BEA > Zn-BEA, which corresponds to the Lewis acidity trends of the three BEA-type metallosilicates that convert glucose to fructose (Fig. 6a and Table 2). However, after a rapid increase in glucose conversion with Zn-BEA after 3 h of reaction, the conversion of Zn-BEA continued to be the highest as the reaction time increased. This may be due to the presence of Brønsted acid sites along with Lewis acid sites. As shown in Fig. 6d, the yield of fructose decreased for all catalysts, while the yield of 5-HMF gradually increased with increasing reaction time. This is a typical result of the cascade conversion of glucose. Notably, the yield of 5-HMF was the highest with Zn-BEA. Although no Brønsted acid sites were observed in these three catalysts in pyridine adsorption IR analysis (Fig. 6a and Table 2), this result may be attributed to the Brønsted acidic nature of the defective silanol groups (Fig. 6b). These silanols may contribute to the production of 5-HMF by the conversion of fructose, but due to their weak acidity, no pyridine adsorption IR peak was detected.

[0060]

[0061] Conclusion

[0062] Co-, Ni-, and Zn-containing BEA-type metallosilicates were successfully prepared via a single-step interzeolite structural transformation of B-MWW. The structural transformation rates were rapid in the order of Ni-BEA (< 1 d), Co-BEA (< 2 d), and Zn-BEA (> 7 d), and the metal substitution resulted in distinct kinetic processes in which the substitution rate of Co was slower than that of the other two metals. These two separate kinetics mainly depended on the solubility of the siliceous BEA seeds and the stability of the hydrated metal ions, respectively, under the acidic-basic conditions of the aqueous synthetic gel. In addition, despite having the lowest thermodynamic substitution energy of Zn in Zn-BEA, it still had the lowest content of isolated framework Zn after 7 days of hydrothermal interzeolite structural transformation due to the kinetically incomplete formation of Zn-BEA. The different chemical coordinations of the framework heteroatoms resulted in stronger Lewis acidity in the order Ni-BEA > Co-BEA > Zn-BEA and higher silanol defect sites in the reverse order. These results directly influenced the Lewis and Brønsted acid-catalyzed glucose conversions, with Ni-BEA exhibiting the highest initial activity and Zn-BEA exhibiting the highest 5-HMF yield due to its subsequent catalytic action on weak Brønsted acidic silanols. These comprehensive results demonstrate that the performance of heterogeneous catalysts is determined by the catalyst synthesis step.

[0063]

[0064] As described above, although the present invention has been described by limited embodiments and drawings, the present invention is not limited thereto, and various modifications and variations are possible within the scope of the technical idea of ​​the present invention and the equivalent scope of the claims to be described below by a person having ordinary skill in the art to which the present invention pertains.

Claims

1. A step of synthesizing a borosilicate MWW zeolite precursor [B-MWW(P)] or an aluminosilicate MWW zeolite precursor [Al-MWW(P)]; A step of dissolving the above B-MWW(P) or Al-MWW(P) and dealuminated siliceous BEA in a transition metal hydrate aqueous solution; A step of adding a tetraethylammonium hydroxide solution or a tetraethylammonium bromide solution to the above transition metal hydrate aqueous solution; A step of adding ammonium fluoride (NH4F) to the above transition metal hydrate aqueous solution and powdering it; and A method for producing a BEA zeolite catalyst, comprising a step of heating and crystallizing the above powder.

2. In paragraph 1, A method for producing a BEA zeolite catalyst, characterized in that after the crystallization step, a washing step and a calcination step are further included.

3. In paragraph 1, A catalyst manufacturing method characterized in that the molar ratio of Si / B in the above B-MWW(P) is 9 to 10.

4. In paragraph 1, A method for producing a BEA zeolite catalyst, characterized in that the Si / Al molar ratio of the above Al-MWW(P) is 12 to 18.

5. In paragraph 1, A method for producing a BEA zeolite catalyst, characterized in that the above transition metal is cobalt (Co), nickel (Ni) or zinc (Zn).

6. In paragraph 1, A method for producing a BEA zeolite catalyst, characterized in that the concentration of the above transition metal hydrate aqueous solution is 0.005 to 0.1 M.

7. In paragraph 1, A method for producing a BEA zeolite catalyst, characterized in that the crystallization time is 1-168 hours.

8. In paragraph 1, A method for producing a BEA zeolite catalyst, characterized in that the BET surface area of ​​the BEA zeolite increases as the molecular weight of the transition metal decreases.

9. In paragraph 1, A method for producing a BEA zeolite catalyst, characterized in that the above BEA zeolite catalyst does not exhibit Brønstedt acidity but exhibits Lewis acidity.

10. In paragraph 9, A method for producing a BEA zeolite catalyst, characterized in that the Lewis acidity increases in the order of Zn-BEA, Co-BEA, and Ni-BEA.

11. In paragraph 1, A method for producing a BEA zeolite catalyst, characterized in that the above BEA zeolite catalyst is a catalyst for a glucose conversion reaction.

12. In paragraph 11, A method for producing a BEA zeolite catalyst, characterized in that the Zn-BEA zeolite catalyst has a higher 5-HMF conversion yield than Co-BEA and Ni-BEA zeolite catalysts.

13. A BEA zeolite catalyst for glucose conversion reaction manufactured by the manufacturing method of any one of claims 1 to 12.

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