Copper silicate catalyst and preparation method thereof

Abstract

A copper silicate-based catalyst according to an exemplary embodiment of the present application includes copper and silica, in which a weight ratio of Cu: Si in the copper silicate-based catalyst is from 30: 70 to 70: 30, and a Cu 2p binding energy of the copper silicate-based catalyst determined by XPS (X-ray photoelectron spectroscopy) analysis is from 932 eV to 934 eV.

Description

TECHNICAL FIELD

[0001] This application claims the benefit of Korean Patent Application No. 10-2024-0009934, filed on January 23, 2024, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

[0002] The present application relates to a copper silicate-based catalyst and a method for preparing the same. BACKGROUND

[0003] Neopentyl glycol (NPG) is a white crystalline material having a melting point of 130°C or more. It is used as an important intermediate for various synthetic resins, and is also widely used as a raw material for various plastic powder coatings, synthetic lubricants, plasticizers, surfactants, fiber processing agents, etc. in industry.

[0004] NPG is generally prepared by a hydroformylation reaction of isobutyraldehyde and formaldehyde to produce hydroxypivalaldehyde (HPA), and then reacting HPA with hydrogen in the presence of a catalyst.

[0005] Generally, a slurry-type Ni-based catalyst is used for the hydrogenation reaction of HPA. In this case, crude NPG as a hydrogenation reaction product contains 2, 2, 4-trimethyl-1, 3-pentanediol (TMPD), hydroxypivalic acid NPG ester (HPNE), etc. Since the boiling points of TMPD and HPNE are very similar to that of NPG, they cannot be separated by simple distillation. Since HPNE is not stable when distilling the reaction mixture and causes a decrease in NPG yield, it is commercially converted into NPG by a saponification reaction by adding sodium hydroxide. However, since the sodium salt of HPA or other organic acids produced by the saponification reaction promotes a decomposition reaction of NPG at a high temperature of 140°C or more, the distillation process is limited. In addition, it is not possible to remove TMPD that is not converted into a non-volatile sodium salt during the saponification reaction.

[0006] Therefore, there has been an effort in the art to produce NPG in a high yield in an economical manner. SUMMARY

[0007] TECHNICAL PROBLEM

[0008] The present application provides a copper silicate-based catalyst and a method for preparing the same.

[0009] TECHNICAL SOLUTION

[0010] One exemplary embodiment of the present application provides a copper silicate-based catalyst comprising copper and silicon oxide, wherein

[0011] The weight ratio of Cu:Si in the copper silicate-based catalyst is 30:70 to 70:30, and

[0012] The Cu 2p binding energy of the copper silicate-based catalyst determined by XPS (X-ray photoelectron spectroscopy) analysis is 932 eV to 934 eV.

[0013] Further, another exemplary embodiment of the present application provides a method of preparing a copper silicate-based catalyst, which includes:

[0014] a step of preparing a co-precipitation slurry by adding a silica sol and an alkaline precipitant to an aqueous solution containing a copper precursor;

[0015] a step of aging the co-precipitation slurry at 80°C to 90°C for more than 3 hours, and then obtaining a dry product by filtering and drying the same;

[0016] a step of mixing the dry product with a fibrous binder and an organic compound, and then preparing a catalyst precursor by molding the same; and

[0017] a step of drying the catalyst precursor, and then sintering the same at 400°C to 650°C, wherein

[0018] the content of the fibrous binder is 0.1% by weight or more and less than 15% by weight, based on the total weight of the dry product.

[0019] Further, another exemplary embodiment of the present application provides a method of preparing neopentyl glycol, which includes a step of performing a hydrogenation reaction by adding a hydroxypivalaldehyde (HPA) solution and hydrogen gas into a hydrogenation reactor, wherein

[0020] the hydrogenation reactor contains the copper silicate-based catalyst.

[0021] Advantageous effects

[0022] According to one exemplary embodiment of the present application, a copper silicate-based catalyst having improved stability can be prepared.

[0023] In particular, according to one exemplary embodiment of the present application, the 2p binding energy, Cu dispersibility, Cu cubic crystallite size, and acid strength characteristics of the catalyst can be optimized by controlling the aging conditions of the co-precipitation slurry and the sintering conditions of the catalyst precursor. Thereby, even under high-temperature and high-pressure reaction conditions for preparing neopentyl glycol at a high yield, the decrease in the strength, reactivity, etc. of the catalyst can be prevented.

[0024] Therefore, when the copper silicate-based catalyst according to one exemplary embodiment of the present application is used for preparing neopentyl glycol, the preparation process can be maintained stable, and thus the economic efficiency can be improved. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1XPS spectra of copper silicate-based catalysts according to Example 1 of the present application are shown. DETAILED DESCRIPTION

[0026] Hereinafter, the present application is described in more detail.

[0027] In the present specification, when a member is described as being "on" another member, it not only includes a case where the two members are in contact with each other, but also includes a case where another member is present between the two members.

[0028] In the present specification, when a part is described as "including" a certain component, it means that it can include another component and does not exclude the other components unless the context clearly dictates otherwise.

[0029] As described above, there has been an effort in the art to produce NPG in an economic manner with a high yield.

[0030] In particular, neopentyl glycol is prepared by hydrogenation of HPA (hydroxypivalaldehyde) in the presence of a catalyst under conditions of high temperature (above 160°C) and high pressure (above 35 bar). Due to elution of catalyst components, the strength and reactivity of the catalyst can decrease under the high temperature, high pressure reaction conditions, and thus the hydrogenation process can be operated unstably.

[0031] Accordingly, the present application aims to provide a copper silicate-based catalyst having excellent stability which can be applied to a preparation process of neopentyl glycol, and a preparation method of the catalyst.

[0032] The copper silicate-based catalyst according to one exemplary embodiment of the present application comprises copper and silicon dioxide, wherein the weight ratio of Cu:Si in the copper silicate-based catalyst is 30:70 to 70:30, and the Cu 2p binding energy of the copper silicate-based catalyst determined by XPS (X-ray photoelectron spectroscopy) analysis is 932 eV to 934 eV.

[0033] In one exemplary embodiment of the present application, the weight ratio of Cu:Si in the copper silicate-based catalyst can be 30:70 to 70:30, 30:70 to 50:50, or 35:65 to 50:50. The weight ratio of Cu:Si in the copper silicate-based catalyst is an index of the content of Cu which is an active component of the catalyst. If the weight ratio of Cu:Si is outside the above range, the activity of the catalyst is undesirably decreased.

[0034] In one exemplary embodiment of the present application, the Cu 2p binding energy of the copper silicate-based catalyst determined by XPS (X-ray photoelectron spectroscopy) analysis can be 932 eV to 934 eV, 933 eV to 934 eV, or 933.6 eV to 933.8 eV.

[0035] In one exemplary embodiment of the present application, the Cu 2p binding energy of the copper silicate-based catalyst determined by XPS (X-ray photoelectron spectroscopy) analysis refers to a main peak that appears as a high peak in the Cu 2p spectrum in the binding energy range of 928.0 eV to 939.0 eV due to a rapid increase in intensity. The Cu 2p binding energy of the copper silicate-based catalyst as a result of XPS (X-ray photoelectron spectroscopy) analysis of 932 eV to 934 eV is a characteristic of the catalyst according to one exemplary embodiment of the present application. Outside the above range, the activity of the catalyst is not expected to decrease.

[0036] In the examples given below, a specific method of measuring the Cu 2p binding energy of the copper silicate-based catalyst as a result of XPS (X-ray photoelectron spectroscopy) analysis is described.

[0037] In one exemplary embodiment of the present application, the Cu dispersion of the copper silicate-based catalyst determined by N2O pulse chemisorption analysis can be 0.5% to 3%, 0.7% to 2.8%, or 0.9% to 2.4%, and the Cu cubic crystallite size can be 200 nm or less, 10 nm to 150 nm, or 39 nm to 97 nm.

[0038] In one exemplary embodiment of the present application, the Cu dispersion and the Cu cubic crystallite size indicate the dispersion of Cu as an active component of the catalyst. If the Cu dispersion and the Cu cubic crystallite size are outside the above range, the activity of the catalyst is not expected to decrease.

[0039] In the examples given below, a specific method of measuring the Cu dispersion and the Cu cubic crystallite size of the copper silicate-based catalyst determined by N2O pulse chemisorption analysis is described.

[0040] In one exemplary embodiment of the present application, the copper silicate-based catalyst is subjected to NH3-TPD (temperature programmed desorption) analysis, and peaks can exist in the weak acid site region of 100°C or more and less than 400°C and the strong acid site region of 400°C or more and 700°C or less, and the total acid amount can be 0.03 mmol to 2.0 mmol, 0.1 mmol to 1.9 mmol, 0.5 mmol to 1.8 mmol, or 1.342 mmol to 1.784 mmol.

[0041] In the examples given below, a specific method of measuring the weak acid site, the strong acid site, and the total acid amount of the copper silicate-based catalyst by NH3-TPD (temperature programmed desorption) analysis is described.

[0042] In one exemplary embodiment of the present application, NH3-TPD analysis investigates the properties of the catalyst such as acid strength and acid sites by adsorbing NH3, which is a base, to the catalyst. If the adsorbed base is desorbed at a low temperature range above 100°C and below 400°C, it means weak acid strength. Also, a desorption peak appearing at a high temperature range above 400°C and below 700°C means strong acid strength. The amount of acid of the weak acid sites and the amount of acid of the strong acid sites of the catalyst vary depending on various properties of the catalyst, for example, the content of the active component, the raw material, the preparation method, the heat treatment method, etc. Therefore, if the amount of acid of the weak acid sites and the amount of acid of the strong acid sites exceed the above ranges, the activity of the catalyst is undesirably decreased due to the change in the surface properties of the catalyst.

[0043] In one exemplary embodiment of the present application, the copper silicate-based catalyst can have a crushing strength of 40N or more, specifically 42N to 150N, or 45N to 70N. If the crushing strength of the copper silicate-based catalyst is less than 40N, the catalyst can be easily damaged when it is placed in the reactor, and a pressure difference can undesirably be formed in the reactor due to the damage in a relatively short period of time.

[0044] A specific method of measuring the crushing strength of the copper silicate-based catalyst is described in the Examples given below.

[0045] In one exemplary embodiment of the present application, the copper silicate-based catalyst can be an extrusion-molded catalyst in the shape of a cylinder having a diameter of 2mm to 6mm and a height of 2mm to 10mm, or an extrusion-molded catalyst in the shape of a cylinder having a diameter of 3mm to 5mm and a height of 3mm to 9mm. If the diameter of the cylindrical catalyst exceeds 6mm or the height thereof exceeds 10mm, the catalytic activity can be undesirably decreased due to the reduction in the surface area. Also, if the diameter of the cylindrical catalyst is less than 2mm or the height thereof is less than 2mm, crushing and drift can undesirably occur under the high-temperature, high-pressure reaction conditions for the preparation of neopentyl glycol.

[0046] The molding of the catalyst is important for the physical durability and flow of the reactants in the reactor. Although a powder catalyst can be advantageous in terms of catalytic activity due to a large surface area caused by a small particle size, the flow of the reactants is limited in a commercial-scale fixed bed reactor, and drift or a pressure difference can occur. Therefore, it is desirable to mold the catalyst by extrusion, compression, coating, etc. The pores formed by the molded catalyst in the fixed bed reactor provide the effect of reducing the pressure difference caused by the reactants supplied at a high flow rate for commercial productivity. In particular, since the extrusion-molded catalyst has the advantage of high durability due to high strength, the possibility of drift or a pressure difference caused by abrasion, crushing, etc. during the long-term use of the catalyst can be reduced.

[0047] In one exemplary embodiment of the present application, a copper silicate-based catalyst can be used for preparing neopentyl glycol.

[0048] Further, the method for preparing a copper silicate-based catalyst according to one exemplary embodiment of the present application includes a step of preparing a co-precipitation slurry by adding a silica sol and an alkaline precipitant to an aqueous solution containing a copper precursor; a step of aging the co-precipitation slurry at 80 to 90°C for 3 hours or more, and then obtaining a dried product by filtering and drying the same; a step of mixing the dried product with a fibrous binder and an organic compound, and then preparing a catalyst precursor by molding the same; and a step of drying the catalyst precursor, and then sintering the same at 400 to 650°C.

[0049] The method for preparing a copper silicate-based catalyst according to one exemplary embodiment of the present application includes a step of preparing a co-precipitation slurry by adding a silica sol and an alkaline precipitant to an aqueous solution containing a copper precursor.

[0050] In one exemplary embodiment of the present application, the copper precursor can be Cu(NO3)2·3H2O, Cu(CO3)2·Cu(OH)2, CuCl2·2H2O, or the like, but is not limited thereto.

[0051] In one exemplary embodiment of the present application, the alkaline precipitant can be an alkali metal hydroxide, an alkali metal carbonate, an alkali metal bicarbonate, a mixture thereof, or the like. More specifically, the alkaline precipitant can be one or more of NH4OH, (NH4)2CO3, NH4HCO3, CH4N2O, NaOH, and Na2CO3, but is not limited thereto.

[0052] When the alkaline precipitant is added, the temperature increased by the heat of neutralization can be lowered to room temperature using cooling water or the like.

[0053] The method for preparing a copper silicate-based catalyst according to one exemplary embodiment of the present application includes a step of aging the co-precipitation slurry at 80 to 90°C for 3 hours or more, and then obtaining a dried product by filtering and drying the same.

[0054] The aging can be performed at 80 to 90°C for 3 hours or more, or at 80 to 90°C for 3 to 8 hours.

[0055] The combination between the copper precursor and the silica is formed by the aging. When the above-mentioned aging temperature and time are satisfied, the copper precursor does not remain unreacted. If the copper precursor remains unreacted, the activity of the catalyst can undesirably decrease.

[0056] After the aging, the co-precipitation slurry can be filtered by a method known in the art without particular limitation.

[0057] In one exemplary embodiment of the present application, the filtered co-precipitation slurry can be dried at 60 to 120°C for 5 to 72 hours, or at 70 to 110°C for 7 to 48 hours.

[0058] The method of preparing a copper silicate-based catalyst according to one exemplary embodiment of the present application includes the step of mixing the dried product with a fiber-based binder and an organic compound, and then preparing a catalyst precursor by molding the same.

[0059] In one exemplary embodiment of the present application, the fiber-based binder can include one or more of glass fibers, carbon fibers, aramid fibers, alumina fibers, aluminum silicate fibers, silicon carbide fibers, and boron fibers.

[0060] In one exemplary embodiment of the present application, the content of the fiber-based binder can be 0.1% by weight or more and less than 15% by weight, 1 to 10% by weight, or 3 to 7% by weight, based on the total weight of the dried product. If the content of the fiber-based binder is less than 0.1% by weight, based on the total weight of the dried product, the physical stability can be undesirably deteriorated at high-temperature, high-pressure reaction conditions due to a significant decrease in the strength of the catalyst. Also, if the content of the fiber-based binder is 15% by weight or more, the productivity can be decreased during the preparation of the catalyst due to poor flowability during the extrusion molding of the catalyst, and the strength of the catalyst can also be decreased due to poor compressibility.

[0061] In one exemplary embodiment of the present application, the content of the organic compound can be 0.1 to 50% by weight, 1 to 40% by weight, or 10 to 30% by weight, based on the total weight of the dried product. The organic compound serves as a lubricant during the molding of the catalyst. If the content of the organic compound is less than 0.1% by weight, based on the total weight of the dried product, the molding can not be possible. Also, if the content exceeds 50% by weight, the strength or activity of the catalyst can be undesirably decreased.

[0062] In one exemplary embodiment of the present application, the organic compound can include one or more of polyvinyl alcohol, isopropyl alcohol, ethanol, polyacrylate, polyethylene glycol, glycerol, starch, dextrin, wax, methyl cellulose, carboxymethyl cellulose, hydroxypropyl methyl cellulose, paraffin, lignosulfonate, stearic acid, and palmitic acid.

[0063] The method of preparing a copper silicate-based catalyst according to one exemplary embodiment of the present application includes the step of drying the catalyst precursor, and then sintering the same at 400 to 650°C.

[0064] In one exemplary embodiment of the present application, the catalyst precursor can be dried at 60 to 120°C for 5 to 24 hours, or at 70 to 110°C for 7 to 20 hours.

[0065] In one exemplary embodiment of the present application, the dried catalyst precursor can be sintered at 400 to 650°C for 5 to 24 hours, or at 450 to 600°C for 6 to 20 hours.

[0066] If the drying conditions and the sintering conditions are out of the above ranges, the catalytic activity can undesirably decrease due to a change in the crystallinity of the catalyst.

[0067] Further, another exemplary embodiment of the present application provides a method of preparing neopentyl glycol, which includes the step of adding a hydroxypivalaldehyde (HPA) solution and hydrogen gas to a hydrogenation reactor and performing a hydrogenation reaction, wherein the hydrogenation reactor contains the copper silicate-based catalyst.

[0068] In one exemplary embodiment of the present application, neopentyl glycol can be prepared using a method known in the art, in addition to using the copper silicate-based catalyst.

[0069] For example, the hydrogenation reactor can be a fixed bed reactor (FBR) loaded with the copper silicate-based catalyst. In this case, there is no need to separate the reaction product from the catalyst, the operation is stable and economical because the reaction temperature and the reaction pressure can be lowered, the catalyst can be easily replaced, and the investment cost can be greatly reduced because the reactor size can be reduced.

[0070] Further, the hydroxypivalaldehyde solution can contain 65 wt% or less of hydroxypivalaldehyde, 10 wt% or less of neopentyl glycol, 15 to 35 wt% of an alcohol, and 15 wt% or less of water. In this case, the generation of by-products can be inhibited because the reaction heat can be minimized without sacrificing reactivity.

[0071] The hydrogenation reaction can be performed at 100 to 250°C, 100 to 200°C, or 100 to 180°C.

[0072] According to one exemplary embodiment of the present application, a copper silicate-based catalyst having improved stability can be prepared.

[0073] In particular, according to one exemplary embodiment of the present application, by controlling the aging conditions of the co-precipitation slurry, the content of the fibrous binder, and the sintering conditions of the catalyst precursor, the 2p binding energy, Cu dispersibility, Cu cubic crystallite size, and acid strength characteristics of the catalyst can be optimized, and thus, even under high-temperature, high-pressure reaction conditions for preparing neopentyl glycol at a high yield, the decrease in the strength, reactivity, etc. of the catalyst can be prevented.

[0074] Accordingly, when a copper silicate-based catalyst according to one exemplary embodiment of the present application is used to produce neopentyl glycol, the production process can be stabilized, and thus economic efficiency can be improved.

[0075] Hereinafter, the present application will be described in detail through specific examples. However, the embodiments according to the present application can be changed into various other forms, and should not be interpreted as being limited to the embodiments described below. The embodiments of the present application are provided to more fully describe the present application to those of ordinary skill in the art.

[0076] <EMBODIMENT>

[0077] <EMBODIMENT 1>

[0078] An aqueous solution of a copper precursor (Cu(NO3)2·3H2O) was prepared in a double jacketed reactor, and a silica sol was added so that the weight ratio of Cu and Si was Cu:Si=30:70. After the addition of an aqueous solution of NaOH, a co-precipitate was prepared by increasing the temperature of the reactor, and was aged at 80℃ for 3 hours. After filtering the co-precipitate and washing with distilled water, the wet cake thus obtained was dried in an oven. The dried product was crushed to obtain a catalyst intermediate powder.

[0079] Based on the total weight of the catalyst intermediate powder, 25 wt% of an organic compound (20 wt% of isopropyl alcohol and 5 wt% of glycerol), 5 wt% of a fiber-based binder (ceramic wool, aluminum silicate), and distilled water were mixed, and the catalyst intermediate was extrusion-molded into a cylindrical shape having a diameter of 3 to 5 mm and a height of 3 to 9 mm using an extruder.

[0080] Finally, a catalyst for producing neopentyl glycol was prepared by sintering the extrusion-molded catalyst intermediate at 550℃ for 8 hours.

[0081] <EMBODIMENT 2>

[0082] A catalyst for producing neopentyl glycol was prepared in the same manner as in Embodiment 1, except that the co-precipitate was prepared so that the weight ratio of Cu and Si was Cu:Si=40:60.

[0083] <EMBODIMENT 3>

[0084] A catalyst for producing neopentyl glycol was prepared in the same manner as in Embodiment 1, except that the co-precipitate was prepared so that the weight ratio of Cu and Si was 50:50.

[0085] <COMPARATIVE EXAMPLE 1>

[0086] A catalyst for producing neopentyl glycol was prepared in the same manner as in Example 1 except that the aging was performed at 65°C for 3 hours instead of at 80°C for 3 hours.

[0087] <Comparative Example 2>

[0088] A catalyst for producing neopentyl glycol was prepared in the same manner as in Example 2 except that the aging was performed at 65°C for 3 hours instead of at 80°C for 3 hours.

[0089] <Comparative Example 3>

[0090] A catalyst for producing neopentyl glycol was prepared in the same manner as in Example 1 except that the sintering was performed at 700°C for 8 hours instead of at 550°C for 8 hours.

[0091] <Comparative Example 4>

[0092] A catalyst for producing neopentyl glycol was prepared in the same manner as in Example 2 except that the sintering was performed at 700°C for 8 hours instead of at 550°C for 8 hours.

[0093] <Comparative Example 5>

[0094] A catalyst for producing neopentyl glycol was prepared in the same manner as in Example 1 except that 30% by weight of an organic compound (20% by weight of isopropyl alcohol and 10% by weight of glycerol) and 15% by weight of a fiber-based binder were used in the extrusion molding step instead of 25% by weight of an organic compound and 5% by weight of a fiber-based binder.

[0095] <Comparative Example 6>

[0096] A catalyst for producing neopentyl glycol was prepared in the same manner as in Example 1 except that no organic compound and no fiber-based binder were used in the extrusion molding step.

[0097] <Comparative Example 7>

[0098] A catalyst for producing neopentyl glycol was prepared in the same manner as in Example 1 except that no fiber-based binder was used in the extrusion molding step.

[0099] <Comparative Example 8>

[0100] A catalyst for producing neopentyl glycol was prepared in the same manner as in Example 1 except that no organic compound was used. However, extrusion was not possible because lubrication could not be smoothly performed in the extruder during the extrusion molding step. As a result, the catalyst could not be prepared.

[0101] <Test Example>

[0102] The hydrogenation reaction was performed at 160°C and 35 bar for 1 hour using an HPA solution consisting of 65 wt% of HPA, 2 wt% of NPG, 25 wt% of 2-ethylhexanol, 5 wt% of H2O, and 3 wt% of a high-boiling material in the presence of the catalyst prepared in the example or comparative example, and the catalytic activity was measured by measuring the amount of hydrogen consumed. The results are shown in Table 1. The catalytic activity is expressed as 100 with respect to the results of Example 1.

[0103] Further, the crushing strength, Cu dispersibility, and Cu cubic crystallite size of the catalysts of the examples and comparative examples were evaluated. The results are shown in Table 1.

[0104] Further, the Cu 2p binding energy and NH3-TPD peak position of the catalysts of the examples and comparative examples were evaluated by XPS analysis. The results are shown in Table 2.

[0105] Further, the XPS spectrum of the copper silicate-based catalyst of Example 1 is shown in Figure 1

[0106] The measurement methods of the evaluation results shown in Table 1 and Table 2 are as follows.

[0107] <Crushing strength>

[0108] The crushing strength was measured using FGN-50B of SHIMPO. More specifically, after placing the catalyst extruded into a cylindrical shape so that the side surface faces the bottom on the strength tester holder, the maximum pressure value was measured when the measurement unit compressed the catalyst downward from the top. The measurement was performed on 20 catalysts, and the results were averaged.

[0109] For Example 1, although the crushing strength of the catalyst intermediate powder was intended to be measured without the extrusion molding step, it was not possible to perform the measurement using the method of FGN-50B of SHIMPO because the particle size of the powder catalyst was as small as about 100 µm. Therefore, the crushing strength of the powder catalyst was evaluated as 0.

[0110] <Cu dispersibility and Cu cubic crystallite size>

[0111] The Cu dispersibility and Cu cubic crystallite size were measured by N2O pulse chemisorption analysis.

[0112] More specifically, using AutoChem of Micromeritics, about 0.2 g of the catalyst sample was filled in a U-tube and pretreated at 250°C for 2 hours under a hydrogen atmosphere. Then, after the pulse injection of N2O using a predetermined volume of a loop at 60°C, the surface area, dispersibility, and cubic crystallite size of Cu were calculated from the cumulative consumption amount of N2O and the Cu weight% of the catalyst.

[0113] ​[Cu 2p binding energy]

[0114] The Cu 2p binding energy was measured by XPS (X-ray photoelectron spectroscopy) analysis.

[0115] More specifically, after preparing a circular pellet sample having a diameter of 2 mm and a thickness of 1 mm by crushing the catalyst, the sample was measured using a monochromatic Al k-alpha X-ray alpha (1486.6 eV) having a size of 400 μm x 800 μm. After obtaining a first XPS spectrum (before correction) by XPS (X-ray photoelectron spectroscopy) under the conditions of a vacuum atmosphere, a measurement range of 925 eV to 970 eV, and a pass energy of 50 eV, a second XPS spectrum (after correction) was obtained by correcting the peaks of the XPS spectrum. The Cu 2p binding energy is the value from the second XPS spectrum.

[0116] [Weak acid sites, strong acid sites, and total acid amount]

[0117] The weak acid sites, strong acid sites, and total acid amount were measured by NH3-TPD (temperature-programmed desorption) analysis.

[0118] More specifically, using AutoChem of Micromeritics, about 0.1 g of the catalyst sample was filled in a U-tube and pretreated at 200℃ for 1 hour under a helium atmosphere. Then, after adsorbing NH3 at 100℃ for 1 hour, the desorption value was measured while raising the temperature to 800℃ at a rate of 5℃ / min under a helium atmosphere.

[0119] [Table 1]

[0120]

[0121]

[0122] [Table 2]

[0123]

[0124] As seen from Table 1 and Table 2, it was determined that the catalysts for preparing neopentyl glycol of Example 1 to Example 3 exhibited excellent catalytic activity compared to the catalysts of Comparative Example 1 to Comparative Example 7, and the Cu 2p binding energy was in the range of 932 eV to 934 eV as a result of XPS (X-ray photoelectron spectroscopy) analysis.

[0125] The catalysts for preparing neopentyl glycol of Comparative Example 1 and Comparative Example 2 showed a decrease in catalytic activity because the copper precursor remained unreacted under low aging temperature conditions. In addition, it can be seen that the catalysts for preparing neopentyl glycol of Comparative Example 3 and Comparative Example 4 exhibited low Cu dispersibility and did not show catalytic activity, although the catalyst strength increased due to Si crystallization into quartz under high sintering temperature conditions. In addition, the catalyst for preparing neopentyl glycol of Comparative Example 5 showed a decrease in catalytic activity because the fiber-based binder was used in excess. Furthermore, the catalysts of Comparative Example 6 and Comparative Example 7, which did not use a fiber-based binder, showed a decrease in catalyst strength and catalytic activity.

[0126] The catalyst for preparing neopentyl glycol according to one exemplary embodiment of the present application, which is an extrusion-molded catalyst in a cylindrical shape, is suitable for a commercial-scale fixed bed reactor to which an unmolded powder catalyst is difficult to apply, and due to excellent strength and durability, can reduce the possibility of drift or pressure difference caused by abrasion, crushing, or the like during long-term use of the catalyst.

[0127] Therefore, since the catalyst for preparing neopentyl glycol according to one exemplary embodiment of the present application can maintain its activity even under high temperature, high pressure reaction conditions due to excellent strength, reactivity, and stability, it can improve the stability of the method of preparing neopentyl glycol and provide excellent catalytic activity.

Claims

1. A copper silicate catalyst comprising copper and silicon dioxide, wherein The weight ratio of Cu:Si in the copper silicate catalyst is 30:70 to 70:30, and The Cu 2p binding energy of the copper silicate-based catalyst determined by XPS (X-ray photoelectron spectroscopy) analysis is 932 eV to 934 eV.

2. The copper silicate catalyst according to claim 1, wherein The copper silicate catalyst has a Cu dispersion of 0.5% to 3% as determined by N2O pulse chemisorption analysis, and a Cu cubic crystallite size of less than 200 nm.

3. The copper silicate catalyst according to claim 1, wherein NH3-TPD (temperature programmed desorption) analysis of the copper silicate catalyst showed peaks in the weak acid site region above 100°C and below 400°C and in the strong acid site region above 400°C and below 700°C, and the total acid content was 0.03 mmol to 2.0 mmol.

4. The copper silicate catalyst according to claim 1, wherein The copper silicate catalyst has a crushing strength of 40N or more.

5. The copper silicate catalyst according to claim 1, wherein The copper silicate catalyst is extruded into a cylindrical catalyst with a diameter of 2 mm to 6 mm and a height of 2 mm to 10 mm. The copper silicate catalyst according to claim 1 , wherein the copper silicate catalyst is used to prepare neopentyl glycol.

7. A method for preparing a copper silicate catalyst according to any one of claims 1 to 6, comprising: a step of preparing a co-precipitation slurry by adding silica sol and an alkaline precipitant to an aqueous solution containing a copper precursor; A step of aging the coprecipitated slurry at 80° C. to 90° C. for more than 3 hours, and then filtering and drying it to obtain a dry product; a step of mixing the dried product with a fiber-based binder and an organic compound, and then preparing a catalyst precursor by shaping it; and a step of drying the catalyst precursor and then calcining it at 400°C to 650°C, wherein The fiber-based binder may be present in an amount of 0.1 wt % or more and less than 15 wt % based on the total weight of the dry product.

8. The method for preparing the copper silicate catalyst according to claim 7, wherein: The alkaline precipitant includes one or more of NH4OH, (NH4)2CO3, NH4HCO3, CH4N2O, NaOH and Na2CO3.

9. The method for preparing the copper silicate catalyst according to claim 7, wherein: The organic compound may be present in an amount of 0.1 wt % to 50 wt % based on the total weight of the dry product.

10. The method for preparing the copper silicate catalyst according to claim 7, wherein: The fiber-based adhesive includes one or more of glass fiber, carbon fiber, aramid fiber, alumina fiber, aluminum silicate fiber, silicon carbide fiber and boron fiber.

11. The method for preparing a copper silicate catalyst according to claim 7, wherein: The organic compound includes one or more of polyvinyl alcohol, isopropyl alcohol, ethanol, polyacrylate, polyethylene glycol, glycerol, starch, dextrin, wax, methylcellulose, carboxymethylcellulose, hydroxypropylmethylcellulose, paraffin, lignin sulfonate, stearic acid and palmitic acid.

12. A method for preparing neopentyl glycol, comprising the steps of adding a hydroxypivalaldehyde (HPA) solution and hydrogen to a hydrogenation reactor for a hydrogenation reaction, wherein The hydrogenation reactor comprises the copper silicate-based catalyst according to any one of claims 1 to 6.

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