Aldehyde hydrogenation catalyst and method for producing same

Abstract

The present invention relates to a nickel diatomaceous earth catalyst and a method for producing the same, the nickel diatomaceous earth catalyst being a catalyst for hydrogenating an aldehyde, the catalyst containing Ni, Zr, and diatomaceous earth, the Ni content being in the range of 40-90 mass% in terms of NiO, the Zr content being in the range of 0.5-10 mass% in terms of ZrO2, and the diatomaceous earth content being in the range of 0.5-10 mass% in terms of ZrO2. The content of silica is in the range of 10-40 mass% in terms of SiO2, and the amount of NH3 desorption in the temperature range of 250-600 DEG C is 1.00 mmol / g or more in an NH3 temperature desorption measurement.

Description

Technical Field

[0001] The present invention relates to a catalyst for the hydrogenation of aldehydes. Background Art

[0002] Catalysts for hydrogenating aldehydes to produce alcohols have been known since ancient times. For example, Patent Document 1 discloses a reduced nickel catalyst containing 3% to 15% of one or more selected from magnesium, calcium, barium, strontium, and zirconium as metal components relative to the nickel in the nickel diatomaceous earth catalyst. The document 1 discloses a method for hydrogenating saturated or unsaturated aldehydes using the reduced nickel catalyst to produce the corresponding alcohol. Furthermore, the document 1 records that in the hydrogenation reaction of aldehydes using a nickel catalyst, the side reaction of generating ethers and acetals is a big problem. Furthermore, it is noted that these side reactions are promoted by the acid present in the catalyst, and it is recorded that by containing an alkaline metal salt in the catalyst, the side reactions are significantly suppressed. In addition, Patent Document 2 records that by making the silica with an alkali metal component fixed on the surface highly dispersed in the catalyst, the side reactions are suppressed and the selectivity of the alcohol becomes high.

[0003] There are also known methods that do not use basic metal components. For example, Patent Document 3 describes that the selectivity for alcohols is improved by using a catalyst that supports a catalytically active component with a gentle concentration gradient from the surface to the center.

[0004] Therefore, in the method of producing alcohols by hydrogenating aldehydes, it is known to improve the selectivity of alcohols by changing the acidic properties of the catalyst used or the supporting state of the active metal. Prior art literature Patent Literature

[0005] Patent Document 1: Japanese Patent Publication No. 44-17127 Patent Document 2: Japanese Patent Application Publication No. 2020-163334 Patent Document 3: Japanese Patent Application Publication No. 2005-279587 Summary of the invention Technical problem to be solved by the invention

[0006] The present invention solves the following problem: When a hydrogenation catalyst is used to hydrogenate aldehyde to produce alcohol, the yield of alcohol is low due to significant side reactions such as the generation of ethers and acetals when the existing catalyst is used. Technical means to solve technical problems

[0007] The present inventors have studied hydrogenation catalysts for producing alcohols by hydrogenating aldehydes, and have found that, among nickel diatomaceous earth catalysts containing Ni, Zr and diatomaceous earth, if a nickel diatomaceous earth catalyst containing a large amount of a solid acid with high acid strength is used, the production of ethers and the like can be suppressed, thereby improving the yield of alcohols. The present invention uses a catalyst based on this finding as a solution to the above-mentioned conventional problems.

[0008] The present invention relates to a nickel diatomaceous earth catalyst (hereinafter also referred to as "the catalyst of the present invention") and a method for producing the same, wherein the nickel diatomaceous earth catalyst is a catalyst for hydrogenating aldehydes, wherein the content of Ni is in the range of 40% to 90% by mass as converted to NiO, the content of Zr is in the range of 0.5% to 10% by mass as converted to ZrO2, and the content of silicon dioxide is in the range of 10% to 40% by mass as converted to SiO2, and in a temperature rise desorption measurement of NH3, the amount of NH3 desorbed in the temperature range of 250°C to 600°C is 1.00 mmol / g or more. Beneficial Effects

[0009] When the catalyst of the present invention is used, in a method for producing alcohol by hydrogenating aldehyde, the generation of ethers and the like caused by side reactions can be suppressed, thereby improving the yield of alcohol. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] [ Figure 1 ]NH3-TPD measurement curves of Example 1, Comparative Example 1 and Comparative Example 2. [ Figure 2 ]XPS curve of Example 1. DETAILED DESCRIPTION

[0011] Hereinafter, the catalyst of the present invention and the method for producing the same will be described in detail. In the present invention, when "to" is used to represent a numerical range, it is considered that the numerical range includes the upper limit and the lower limit. [Catalyst of the present invention] The catalyst of the present invention is a nickel diatomaceous earth catalyst, characterized in that the nickel diatomaceous earth catalyst is a catalyst for hydrogenating aldehydes, the catalyst comprises Ni, Zr and diatomaceous earth, the Ni content is in the range of 40 mass % to 90 mass % when converted to NiO, the Zr content is in the range of 0.5 mass % to 10 mass % when converted to ZrO2, the silicon dioxide content is in the range of 10 mass % to 40 mass % when converted to SiO2, and in the temperature rise desorption measurement of NH3, the NH3 desorption amount in the temperature range of 250°C to 600°C is 1.00 mmol / g or more.

[0012] As described in Patent Document 1, in a catalyst for producing alcohol by hydrogenating aldehyde, the acid contained in the catalyst promotes a side reaction (a reaction to produce a compound other than alcohol), and therefore it is known that the acid can be reduced by adding a basic metal, etc. In contrast, the nickel diatomaceous earth catalyst containing Ni, Zr and diatomaceous earth of the present invention is a catalyst containing a large amount of a solid acid with a high acid strength.

[0013] The strength and amount of solid acid can be determined by measuring the NH3 temperature release. This measurement uses the phenomenon that NH3 is adsorbed on solid acid and the adsorbed NH3 is released by heating. NH3 adsorbed on solid acid with high acid strength will only release at high temperature because it is strongly adsorbed on the solid acid. Therefore, if the amount of NH3 released corresponding to the heating temperature is measured, the amount of solid acid corresponding to the acid strength can be determined.

[0014] In the NH3 temperature desorption measurement, the amount of NH3 desorbed by the catalyst of the present invention in the temperature range of 250°C to 600°C (referred to as the high temperature range) is 1.00 mmol / g or more in the entire high temperature range. As shown in Table 2 described later, the amount of NH3 desorbed by the catalyst of Example 1 of the present invention in the temperature range of 100°C to less than 250°C (referred to as the low temperature range) is 0.39 mmol / g in the entire low temperature range, but the amount of NH3 desorbed in the high temperature range of 250°C to 600°C increases significantly, and is 1.84 mmol / g in the entire high temperature range. This indicates that the catalyst of the present invention has a large amount of NH3 desorbed in the high temperature range, and contains a large amount of solid acid with high solid acid strength (hereinafter also referred to as "strong solid acid").

[0015] The temperature change of NH3 desorption is shown in Figure 1 NH3-TPD measurement curve. The catalyst of Example 1 of the present invention has a NH3-TPD curve of about 0.3×10 -3 mmol / g or less, but the NH3 desorption amount increases sharply in the high temperature region of 250℃~600℃, and is about 0.3×10 -3 mmol / g~about 0.7×10 -3 mmol / g, and the NH3 desorption amount in the high temperature region is particularly large. In addition, the NH3 desorption amount in the low temperature region and the high temperature region as a whole is a value obtained by integrating the NH3 desorption amount at the measurement temperature in each temperature region.

[0016] The catalyst of the present invention preferably has an overall NH3 desorption amount of 1.10 mmol / g or more in the high temperature region, more preferably in the range of 1.10 mmol / g or more to 3.00 mmol / g or less, and particularly preferably in the range of 1.10 mmol / g or more to 2.00 mmol / g or less. In addition, the NH3 desorption amount of the catalyst of the present invention in the low temperature region may be 0.20 mmol / g or more, in the range of 0.20 mmol / g or more to 1.00 mmol / g or less, or in the range of 0.20 mmol / g to 0.40 mmol / g. Even if the catalyst of the present invention has a large NH3 desorption amount in the low temperature region, the yield of alcohol is high.

[0017] The catalyst of the present invention contains Ni. In the catalyst, Ni exists in the state that metal Ni, Ni oxide or a part thereof is doped into diatomite. In the reaction of hydrogenating aldehyde, metal Ni becomes an active metal. However, metal Ni is easily oxidized in the atmosphere. Therefore, it is known that there are oxide catalysts that are pre-included in the catalyst in the state of Ni oxide and are pre-treated before the reaction to be reduced to metal Ni, and reduction-stabilized catalysts that pre-form an oxide film on the surface of metal Ni and pre-treat it before the reaction to remove the oxide film. The catalyst of the present invention can be any one of them. From the viewpoint of the simplicity of pretreatment, reduction-stabilized catalysts are preferred. In addition, if Ni is bonded to the silicon dioxide (SiO2) contained in the diatomite and is doped into the diatomite, a strong solid acid will be generated, so it is preferred that at least a part of Ni is bonded to the silicon dioxide of the diatomite.

[0018] The Ni content of the catalyst of the present invention is in the range of 40% to 90% by mass in terms of NiO relative to the total amount of the catalyst. If the content increases, the activity in the hydrogenation reaction of aldehydes increases, but since the price of the catalyst also increases, the Ni content in the catalyst is preferably in the range of 50% to 85% by mass, and more preferably in the range of 60% to 80% by mass, in consideration of economic efficiency.

[0019] The catalyst of the present invention contains Zr. In the catalyst, Zr is believed to exist in the state of oxide, in the state of being incorporated into diatomaceous earth, or in the state of both. If Zr is incorporated into diatomaceous earth, it forms a bond with the silicon dioxide contained in the diatomaceous earth, and the electronic state of Zr changes. The change in the electronic state can be confirmed by XPS measurement, and the energy level moves to a position different from that of Zr in the oxide state. It is also believed that the bonding of silicon dioxide and Zr will generate a strong solid acid, which affects the amount of NH3 dissociation. Therefore, the Zr contained in the catalyst of the present invention is preferably in a state in which part or all of it is incorporated into diatomaceous earth.

[0020] like Figure 2As shown in the XPS curve, in the catalyst of Example 1 of the present invention, the bond energy of Zr contained in the catalyst (peak position derived from 3d orbital) is 1 eV higher than the bond energy of ZrO2, indicating that at least a portion of Zr contained in the catalyst of Example 1 is bonded to the silica of diatomaceous earth. In the catalyst of the present invention, the bond energy of Zr is preferably higher than the bond energy of ZrO2 by 0.4 eV or more, and more preferably higher by 0.5 eV or more.

[0021] The Zr content of the catalyst of the present invention is in the range of 0.5 mass % to 10 mass % as calculated as ZrO2 relative to the total amount of the catalyst. If the Zr content is within this range, a strong solid acid is easily generated. The Zr content is preferably in the range of 1 mass % to 8 mass %, more preferably in the range of 1 mass % to 6 mass %.

[0022] The catalyst of the present invention contains diatomaceous earth. Diatomaceous earth is a carrier of Ni and Zr. Diatomaceous earth has silicon dioxide as a main component, and in the catalyst of the present invention, as described above, a part of Ni and Zr is preferably bonded to the silicon dioxide of diatomaceous earth. The content of diatomaceous earth in the catalyst of the present invention is preferably in the range of 10% to 40% by mass, more preferably in the range of 10% to 30% by mass, and particularly preferably in the range of 15% to 25% by mass.

[0023] Since the main component of diatomaceous earth is silicon dioxide, the content of diatomaceous earth contained in the catalyst of the present invention can be regarded as the silicon dioxide content. In the catalyst of the present invention, the silicon dioxide content is preferably in the range of 10% to 40% by mass, more preferably in the range of 10% to 30% by mass, and particularly preferably in the range of 15% to 25% by mass. In addition, in addition to diatomaceous earth, the catalyst of the present invention may also contain silicon dioxide particles as a shaping agent or a pore-forming agent.

[0024] The silica content of the catalyst of the present invention is the total amount including the silica of the forming agent and the pore-forming agent, but since the silica content is mainly composed of silica of diatomaceous earth, when the forming agent, the pore-forming agent, etc. are contained, the amount of silica other than the diatomaceous earth is limited according to the general blending amount of the forming agent, the pore-forming agent, etc. According to the blending amount of these raw materials, the amount of silica derived from the forming agent, the pore-forming agent, etc. can be regarded as 5% by mass or less, for example. In this case, the amount of silica derived from diatomaceous earth is 5% by mass to 35% by mass in the amount of 10% by mass to 40% by mass of silica contained in the catalyst of the present invention.

[0025] The catalyst of the present invention preferably has a Ni crystallite diameter in the range of 2nm to 8nm, more preferably in the range of 3nm to 7nm, and particularly preferably in the range of 4nm to 6nm. The Ni contained in the catalyst of the present invention can be obtained based on the diffraction peak obtained by X-ray diffraction measurement. In the present invention, the Ni crystallite diameter represents the crystallite diameter of metal Ni when the catalyst of the present invention is a reduction-stabilized catalyst, and represents the crystallite diameter of NiO when the catalyst of the present invention is an oxide catalyst. If the Ni crystallite diameter becomes smaller, the hydrogenation activity of the catalyst of the present invention tends to become higher.

[0026] The catalyst of the present invention preferably has a specific surface area of ​​80 m 2 / g or more, more preferably 90m 2 / g or more, particularly preferably 100m 2 In the catalyst of the present invention, if the specific surface area is within the above range, its hydrogenation activity tends to be high. In addition, the specific surface area of ​​the catalyst of the present invention can be 300m 2 / g or less, can be 250m 2 / g or less, and can also be 200m 2 / g or less.

[0027] The catalyst of the present invention is preferably a shaped body. In the method of producing alcohol by hydrogenating aldehyde, the catalyst of the present invention can be used in powder form, but the shaped body is more easily separated and recovered after the reaction, so it is preferred. The shape of the shaped body can be any existing known shape. For example, spherical, cylindrical or similar shapes are better, preferably cylindrical or similar shapes. The columnar shape also includes cylindrical, trilobal, quadrilobal and other shapes. Specifically, the shape of the catalyst of the present invention is columnar, preferably with a diameter of 0.5 mm to 5 mm and a length of 1 mm to 10 mm.

[0028] The catalyst of the present invention can be particularly suitable for the method of making alcohol by hydrogenating aldehyde. However, the catalyst of the present invention can also be applied to the reaction in which Ni becomes an active species. For example, it can also be used for the hydrogenation of unsaturated compounds such as ethylene, propylene, benzene, toluene, etc.

[0029] The present invention includes a method for producing the catalyst of the present invention (hereinafter also referred to as "the production method of the present invention"). The production method of the present invention will be described in detail below.

[0030] [Production method of the present invention] The method for producing a catalyst of the present invention comprises the following steps (a) to (g). (a) an acidic aqueous solution preparation step, obtaining an acidic aqueous solution in which Ni and Zr are dissolved; (b) an alkaline suspension preparation step to obtain an alkaline suspension in which at least one of NaOH and Na2CO3 is dissolved and diatomaceous earth is dispersed; (c) a neutralization step of adding the acidic aqueous solution to the alkaline suspension to obtain a mixed solution; (d) a aging step of adjusting the pH of the mixed solution to 6.5 or less and maintaining the pH for more than 30 minutes; (e) a re-aging step, wherein the pH of the mixed solution obtained in the aging step is adjusted to a range of 8.5 to 9.5 and maintained for more than 60 minutes to obtain a precursor slurry; (f) a separation step of separating the precursor from the precursor slurry; (g) A firing step of firing the precursor. Each process is described in detail.

[0031] [Acidic Aqueous Solution Preparation Step] The manufacturing method of the present invention includes an acidic aqueous solution preparation step of obtaining an acidic aqueous solution in which Ni and Zr are dissolved. In this step, it is important that Ni and Zr are dissolved and ionized. The ionized Ni and Zr establish a bond with diatomaceous earth in the neutralization step, aging step, and re-aging step described later to form a strong solid acid.

[0032] In this process, Ni raw material and Zr raw material are dissolved in water to prepare an acidic aqueous solution. The Ni raw material is not limited as long as it is a substance that dissolves in an acidic aqueous solution. For example, Ni sulfate, Ni nitrate, Ni acetate, metallic Ni, etc. can be used. In addition, the Zr raw material is not limited as long as it is a substance that dissolves in an acidic aqueous solution. For example, Zr sulfate, Zr nitrate, etc. can be used. In the case where these raw materials are insoluble in water, acid can be used to dissolve. The type of acid is not limited, for example, general inorganic acids such as sulfuric acid, nitric acid, and hydrochloric acid can be used.

[0033] The content of Ni and Zr contained in the acidic aqueous solution obtained in this process can be adjusted according to the composition of the catalyst finally prepared. For example, the content of Ni can be adjusted to a range of 1% to 12% by mass, or 3% to 10% by mass, or 5% to 7% by mass. In addition, the content of Zr can be adjusted to a range of 0.01% to 2% by mass, or 0.05% to 1% by mass, or 0.1% to 0.5% by mass.

[0034] In addition, the pH of the acidic water container obtained in this step is preferably 4 or less, more preferably 3 or less, and particularly preferably 2.5 or less. In addition, the lower limit of the pH is not limited, and it may be 1 or more. If the pH is within the above range, Ni and Zr are stably present in the acidic aqueous solution.

[0035] [Alkaline aqueous solution preparation step] The manufacturing method of the present invention includes an alkaline suspension preparation step of obtaining an alkaline suspension in which at least one of NaOH and Na2CO3 is dissolved and diatomaceous earth is dispersed. In this step, it is important that the diatomaceous earth is dispersed in the solution as a solid, and a part of it (mainly the surface) is dissolved. The main component of diatomaceous earth is silicon dioxide, which dissolves in an alkaline aqueous solution. However, if the diatomaceous earth is completely dissolved, the pores of the diatomaceous earth will also disappear, so a suspension in which the diatomaceous earth exists in a solid form is prepared in this step. As a part of the diatomaceous earth gradually dissolves in the suspension, it becomes easy for Ni and Zr in the acidic aqueous solution mixed in the subsequent neutralization step to form a bond with the diatomaceous earth.

[0036] The alkaline suspension can be prepared by a method of adding diatomaceous earth after dissolving at least one of NaOH and Na2CO3 in water, or by a method of adding at least one of NaOH and Na2CO3 after dispersing diatomaceous earth in water. The amount of at least one of NaOH and Na2CO3 added is not limited, as long as the amount necessary to make the pH below 6.5 in the subsequent neutralization step is added.

[0037] The content of diatomaceous earth contained in the alkaline suspension obtained in this step can be adjusted according to the composition of the catalyst finally prepared. For example, the content of diatomaceous earth can be adjusted to a range of 1% to 20% by mass, or 2% to 10% by mass, or 3% to 6% by mass. However, if the content of diatomaceous earth is too low, the diatomaceous earth will be completely dissolved and will no longer be a suspension, so it is recommended to adjust the content to a degree that the diatomaceous earth can exist in a solid state.

[0038] The pH of the alkaline suspension obtained in this step is preferably in the range of 9 to 12.5, more preferably in the range of 10 to 12. If the suspension is left at a high pH for a long time, the diatomaceous earth will dissolve, so it is preferred to proceed to the next step before the diatomaceous earth is completely dissolved.

[0039] [Neutralization process] The production method of the present invention includes a neutralization step of adding the acidic aqueous solution to the alkaline suspension to obtain a mixed solution with a pH of 6.5 or less. This step is a step of precipitating Ni and Zr dissolved in the acidic solution as a precipitate through a neutralization reaction and forming a bond with Zr on the surface of diatomite. Therefore, it is preferred to add the acidic aqueous solution to the alkaline suspension in which the diatomite is partially dissolved.

[0040] The liquid temperatures of the mixed acidic aqueous solution and the alkaline suspension are preferably in the range of 65° C. to 95° C., more preferably in the range of 75° C. to 85° C. If the liquid temperatures of the acidic aqueous solution and the alkaline suspension are in this range, the bonding reaction of Zr and diatomaceous earth is promoted.

[0041] The total amount of the mixed acidic aqueous solution is preferably added within 15 to 120 minutes, more preferably within 30 to 90 minutes. If the total amount of the acidic aqueous solution is added within such a time, the bond between Zr and diatomaceous earth is easily formed.

[0042] If the pH of the mixed solution does not become less than 6.5 after adding the total amount of the acidic aqueous solution, it is recommended to add the acidic aqueous solution as needed to adjust the pH to the above range. As for the acidic aqueous solution usable here, an aqueous solution containing sulfuric acid, nitric acid, hydrochloric acid, acetic acid or a mixture thereof can be used.

[0043] [Ripening process] The manufacturing method of the present invention includes a step of keeping the mixed solution obtained in the neutralization step for more than 30 minutes. In this step, it is important to promote the reaction of forming a bond with Zr on the surface of diatomaceous earth. The holding time is preferably more than 45 minutes, more preferably more than 60 minutes. The upper limit of the holding time is not limited, but from the perspective of productivity, it can be less than 600 minutes, less than 300 minutes, or less than 150 minutes. At this time, it is preferably kept in a stirred state.

[0044] The temperature of the mixed solution in the aging step is preferably in the range of 65° C. to 95° C., and more preferably in the range of 75° C. to 85° C. When the temperature of the mixed solution is within the above range, the reaction of establishing a bond between Zr and diatomaceous earth is promoted.

[0045] [Re-aging process] The manufacturing method of the present invention includes a step of adjusting the pH of the mixed solution obtained in the aging step to a range of 8.5 to 9.5 and maintaining the pH for more than 60 minutes to obtain a precursor slurry. In this step, it is important to form a bond between Ni and diatomaceous earth by aging the mixed solution at a different pH from that in the aging step.

[0046] In this process, an alkaline compound is added to the mixed solution obtained in the aging process to adjust the pH to a range of 8.5 to 9.5. The added alkaline compound can use a conventionally known compound. For example, NaOH, Na2CO3, ammonia, etc., or an aqueous solution dissolved therein can be used. By adjusting the pH to this range and aging for more than 1 hour, the bond between Ni and diatomaceous earth is further formed. The temperature of the mixed solution during re-aging is preferably in the range of 65°C to 95°C, and more preferably in the range of 75°C to 85°C. If the temperature of the mixed solution is within the range, the reaction of forming a bond between Ni and diatomaceous earth will be promoted.

[0047] [Separation process] The manufacturing method of the present invention includes a step of separating the precursor from the precursor slurry obtained in the above step. In this step, the precursor can be separated from the precursor slurry using a conventionally known method. For example, the following methods can be used: a method of removing water using a dryer, a method of separating from water by filtration, a method of separating from water by centrifugation, etc.

[0048] In the case where the precursor slurry contains impurities generated by neutralization reaction, etc., the impurities can be removed by suspension washing, wherein the separated precursor is suspended in water and stirred before being separated again, or circulation washing, wherein a washing liquid such as water is circulated in the catalyst precursor to wash it. In particular, in the case where the precursor contains a large amount of sulfur, it is preferred to remove sulfur by washing because of concerns that the catalyst activity may be reduced. In addition, in the case where nitric acid ions are contained, since they will become NO generated in the firing step described later, X For example, it is preferred to wash in such a way that the conductivity of the filtrate after washing becomes 5mS / cm or less.

[0049] The separated precursor can be formed into various shapes as needed. For example, it can be formed into a spherical shape, a columnar shape or a shape similar thereto, preferably into a columnar shape or a shape similar thereto. The columnar shape also includes shapes such as a cylindrical shape, a trilobate shape, and a quadrilobate shape. Specifically, it is preferably formed into a columnar shape, and its diameter is in the range of 0.5 mm to 5 mm and its length is in the range of 1 mm to 10 mm. Regarding the method of forming into such a shape, existing known methods such as tablet forming and extrusion forming can be used.

[0050] [Firing process] The manufacturing method of the present invention includes a step of firing the precursor separated in the above step. In this step, it is important to decompose the precipitate contained in the precursor to generate nickel oxide. The fired precursor can be used as an oxide catalyst in a method for hydrogenating aldehydes to produce alcohols. When using an oxide catalyst, a pretreatment is required, and the pretreatment is to reduce the nickel oxide to a metallic state using a reducing substance such as hydrogen.

[0051] In this process, the precursor can be fired using an existing well-known device. For example, the catalyst precursor can be fired using a muffle furnace, a rotary kiln, a gas furnace, etc. In addition, the firing temperature depends on the temperature at which the precursor decomposes, and it is preferably fired in a temperature range of 300° C. to 500° C. In addition, the firing time also depends on the amount of the precursor, and it can be fired within a range of 1 hour to 24 hours. The firing atmosphere is preferably an air atmosphere, and it can also be fired in a state of circulating air.

[0052] In this process, as needed, the oxide catalyst obtained after the calcined precursor can be reduced by hydrogen, etc. For example, the oxide catalyst is filled into a reaction vessel, and the reaction temperature is maintained at 380°C to 450°C for 1 hour to 48 hours under hydrogen flow, thereby nickel oxide can be reduced to metallic nickel. In addition, for the metallic nickel generated by reducing nickel oxide, if it is directly exposed to the atmosphere, there is a situation where heat is generated due to the oxidation reaction and the catalyst burns. Therefore, after reducing the nickel oxide, it is recommended to gradually supply oxygen to form a film of nickel oxide on the surface of the metallic nickel. In addition, carbon dioxide, etc. can also be adsorbed on the surface of the metallic nickel. The catalyst obtained by such a reduction stabilization step can be used as a reduction stabilization catalyst in a method for hydrogenating aldehydes to manufacture alcohols. Compared with the above-mentioned oxide catalyst, the reduction stabilization catalyst greatly reduces the time required for pretreatment, so it is preferred.

[0053] Hereinafter, examples of the present invention are shown together with comparative examples. In addition, the present invention is not limited to these examples. In the examples and comparative examples, various measurements or evaluations were performed as follows.

[0054] [pH measurement] The pH value was measured at a liquid temperature of 40° C. using a pH meter (“MM43-X” manufactured by Yamagata Toa DKK Co., Ltd.) and a pH electrode (“GST-5841C” manufactured by Yamagata Toa DKK Co., Ltd.).

[0055] [Composition Analysis] (Ni, Zr and Si) The sample was dissolved in acid, and the filtrate was diluted with water to an appropriate concentration, and then the contents of Ni, Zr and Si were measured using an ICP emission spectrometer (manufactured by Agilent Technologies, 730ICP-OES, inductively coupled plasma emission spectrometry). In addition, based on the total amount of the catalyst, each content was calculated by converting Ni to NiO, Zr to ZrO2, and Si to SiO2.

[0056] [NH3-TPD determination] The amount of ammonia released is measured by the ammonia temperature desorption method (NH3-TPD method). Using BELCAT-II (registered trademark) manufactured by Microtrac Bel, 0.05 g of sample is placed in the measuring unit and pretreated at 250°C for 1 hour in a hydrogen atmosphere. The temperature is then set to 100°C, and ammonia is introduced and adsorbed for 1 hour. Next, after exhaust treatment at 100°C for 1 hour in a helium atmosphere, the temperature is raised from 100°C to 600°C at 10°C per minute under a helium flow of 30 ml per minute, and the amount of ammonia released as the temperature rises is detected with a TCD detector, once per second. Finally, the calibration factor is calculated based on the TCD signal intensity under 100% helium flow and the TCD signal intensity of the 5.14 Vol%-NH3 / He mixed gas. Using this calibration factor, the TCD signal from 100°C to 600°C is converted into NH3 amount (mmol), and this is divided by the sample weight to obtain the amount of ammonia released per 1g of sample at each time. A graph is made with the amount of ammonia released per 1g of sample as the vertical axis and the time as the horizontal axis, and the time from the time when the temperature reaches 250°C to the time when the temperature reaches 600°C is integrated to obtain the amount of ammonia released at 250°C to 600°C. In addition, the amount of ammonia released at 100°C or above to less than 250°C is also obtained by the same method. These calculations are performed using the analysis software that comes with the device.

[0057] [Crystalline diameter measurement] The samples were subjected to X-ray diffraction measurement using an X-ray diffraction device (Rigaku MultiFlex) manufactured by Rigaku Co., Ltd. First, the sample to be measured was crushed and loaded into a sample plate, and X-ray diffraction (source Cu-Kα ray) was measured under the conditions of tube voltage 40kV, tube current 20mA, scanning range 10°~70°, divergence slit 1.0mm, scattering slit 1.0mm, light receiving slit 0.3mm, and scanning speed 4° / min. The diffraction peak with a peak near 2θ=44° was detected by X-ray diffraction measurement, and the crystallite diameter of Ni was calculated by Scherrer's formula using analytical software (JADE Version 5.0). In addition, when calculating the NiO crystallite diameter of the oxide catalyst, it was calculated based on the diffraction peak with a peak near 2θ=62°.

[0058] [Specific surface area measurement] The specific surface area was calculated by the nitrogen adsorption method (BET method). Specifically, a specific surface area measuring device (manufactured by Mountech, Macsorb 1220) was used to place about 0.1 g of the sample in the measuring unit. After degassing for 40 minutes at 250°C in a nitrogen gas flow, the sample was kept at liquid nitrogen temperature in a mixed gas flow of 30% by volume of nitrogen and 70% by volume of helium to allow nitrogen to be adsorbed on the sample in equilibrium. Then, the temperature of the sample was gradually raised to room temperature while the mixed gas was allowed to flow, and the amount of nitrogen released during the process was measured, and the amount was divided by the weight of the sample after the measurement to calculate the specific surface area of ​​the sample.

[0059] [XPS measurement] XPS measurement was performed under the following conditions using a measurement apparatus (Thermo Fisher: ESCALAB 220I-X). In addition, a commercially available reagent (zirconium oxide, 3N, manufactured by Kanto Chemical Co., Ltd.) was used as a standard sample. Line source: monochromatic Al Kα line Accelerating voltage, current: 10KV, 19.0mA Pass energy: 20eV Dwell time: 50ms Energy step: 0.1eV

[0060] [Activity evaluation: hydrogenation reaction of aldehydes] <Preprocessing> After adding 4.0 g of the sample to the glass tube, the glass tube was kept at 150° C. for 60 minutes under a hydrogen flow. Then, the glass tube was replaced with nitrogen and cooled to room temperature. Then, the sample was placed in an autoclave in a nitrogen atmosphere. <Hydrogenation Test> 100.3 g of n-butylaldehyde was injected into the autoclave. After injection, the temperature was raised to 100° C. while stirring at 400 rpm. After heating, hydrogen was injected until the pressure in the autoclave reached 5 MPa, and the pressure was maintained at 5 MPa for 2 hours. After maintaining, it was cooled to room temperature to obtain a reaction solution. <Analysis> The obtained reaction solution was analyzed by gas chromatography (GC-14B manufactured by Shimadzu Corporation) to measure the mass content of n-butylaldehyde (NBD), n-butyl alcohol (NBA), dibutyl ether (Et), 2-ethyl-1,3-hexanediol (Diol), and butyraldehyde dibutyl acetal (Ac). Then, the mass content was converted into the molar content of each component, and the conversion rate and selectivity were calculated according to the following formula. [Conversion rate] Conversion rate (%) = (NBD molar content after reaction - NBD molar content before reaction) / NBD molar content before reaction × 100 [NBA selection rate] NBA selectivity (%) = NBA molar content after reaction / (NBD molar content after reaction - NBD molar content before reaction) × 100 [Et selection rate] Et selectivity (%) = Et molar content after reaction × 2 / (NBD molar content after reaction - NBD molar content before reaction) × 100 [Diol selection rate] Diol selectivity (%) = Diol molar content after reaction × 2 / (NBD molar content after reaction - NBD molar content before reaction) × 100 [Ac selection rate] Ac selectivity (%) = Ac molar content after reaction × 3 / (NBD molar content after reaction - NBD molar content before reaction) × 100

[0061] [Example 1] Acidic aqueous solution preparation process After 1418.0 g of nickel sulfate hydrate [Ni(SO4)2·6H2O] (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was dissolved in 5.4 L of tap water, 94.0 g of zirconium sulfate solution (manufactured by Daiichi Kinzoku Chemical Industry Co., Ltd.) was added and the temperature was adjusted to 80° C. to prepare an acidic aqueous solution. The pH of the acidic aqueous solution was 2.1.

[0062] Alkaline suspension preparation process 3.1 L of tap water was poured into a 15 L stirring tank, 333.0 g of sodium carbonate (Na2CO3, manufactured by Kanto Chemical Co., Ltd.) was dissolved therein, and the temperature was adjusted to 80°C. Then, 76.3 g of diatomaceous earth [Celite505] (manufactured by Imerys) and 53.5 g of diatomaceous earth [FilterCel] (manufactured by Imerys) were added. After that, the diatomaceous earth was dispersed by stirring for 60 minutes to prepare an alkaline suspension. The pH of the alkaline suspension was 11.3. By using two types of diatomaceous earth, good formability and good bonding with Ni and Zr can be obtained.

[0063] Neutralization process The acidic aqueous solution was added to the alkaline suspension using a tube pump over 80 minutes to obtain a mixed solution having a pH of 6.3.

[0064] Aging process While maintaining the mixed solution at 80° C., stirring was continued for 1 hour.

[0065] Re-aging process 645.0 g of sodium carbonate (manufactured by Kanto Chemical Co., Ltd.) was dissolved in 3.0 L of tap water and adjusted to 80° C. to prepare an alkaline aqueous solution for pH adjustment. This was added to the mixed solution after the aging step using a tube pump over 10 minutes to adjust the pH to 9.5. After the addition was completed, the mixture was kept at 80° C. and stirred for 120 minutes to obtain a precursor slurry.

[0066] Precursor separation process The precursor slurry was filtered under reduced pressure using a suction filter to obtain a cake-like precursor. The precursor was put into 6L warm water adjusted to 40°C, filtered and suspended for washing. This process was repeated until the conductivity of the filtrate reached 1.5mS / cm. The cake-like precursor was dried at 120°C for 12 hours using a box dryer. The dried cake was crushed using a hammer crusher to obtain a powdered precursor.

[0067] Catalyst precursor calcining process The above precursor was formed into a cylindrical shape with a diameter of 3.2 mm and a height of 3.2 mm using an ingot forming machine. The precursor was fired at 370° C. for 6 hours using a muffle furnace to obtain an oxide catalyst. Further, the oxide catalyst was reduced at 430° C. for 10 hours under a hydrogen atmosphere and stabilized at 80° C. to obtain a catalyst. The manufacturing conditions are shown in Table 1. In addition, the above-mentioned measurements or evaluations were performed using the sample. The results are shown in Table 2.

[0068] The NH3-TPD measurement curve of this catalyst is shown together with the catalysts of Comparative Example 1 and Comparative Example 2. Figure 1 . Figure 1 The NH3 desorption amount and the heating temperature are shown accordingly. In addition, the XPS curve of Zr of the catalyst is compared with that of ZrO2, as shown in Figure 2 .

[0069] [Example 2] A catalyst was obtained in the same manner as in Example 1 except that 500.0 g of sodium carbonate (manufactured by Kanto Chemical Co., Ltd.) was used in the re-aging step and the pH of the mixed solution was adjusted to 8.8. The above-mentioned measurements or evaluations were performed on the obtained catalyst.

[0070] [Example 3] A catalyst was obtained in the same manner as in Example 1 except that 64.1 g of diatomaceous earth [Celite 505] (manufactured by Imerys) and 45.0 g of diatomaceous earth [FilterCel] (manufactured by Imerys) were added in the alkaline suspension preparation step. The above-mentioned measurements or evaluations were performed on the obtained catalyst.

[0071] [Example 4] A catalyst was obtained in the same manner as in Example 1 except that 43.1 g of a zirconium sulfate solution (manufactured by Daiichi Kinzo Chemical Industry Co., Ltd.) was added in the acidic aqueous solution preparation step, and 64.1 g of diatomaceous earth [Celite 505] (manufactured by Imerys) and 45.0 g of diatomaceous earth [FilterCel] (manufactured by Imerys) were added in the alkaline suspension preparation step. The obtained catalyst was subjected to the above-mentioned measurements or evaluations.

[0072] [Comparative Example 1] A catalyst was obtained in the same manner as in Example 1 except that 379.5 g of sodium carbonate (manufactured by Kanto Chemical Co., Ltd.) was used in the re-aging step and the pH of the mixed solution was adjusted to 7.5. The above-mentioned measurements or evaluations were performed on the obtained catalyst.

[0073] [Comparative Example 2] A catalyst was obtained in the same manner as in Example 1 except that the holding time in the re-aging step was 0. The above-mentioned measurements or evaluations were performed on the obtained catalyst.

[0074] [Table 1]

[0075] [Table 2]

Claims

1. A nickel diatomite catalyst, characterized in that The nickel diatomaceous earth catalyst is a catalyst for hydrogenating aldehydes. The catalyst comprises Ni, Zr and diatomaceous earth, The content of Ni is in the range of 40 mass % to 90 mass % in terms of NiO. The content of Zr is in the range of 0.5 mass % to 10 mass % as converted to ZrO2. The content of silicon dioxide is in the range of 10 mass % to 40 mass % as SiO2. In the temperature-increasing desorption measurement of NH 3 , the amount of NH 3 desorbed in the temperature range of 250° C. to 600° C. was 1.00 mmol / g or more.

2. The nickel diatomite catalyst according to claim 1, characterized in that The diameter of Ni crystallites is in the range of 2nm to 8nm.

3. The nickel diatomite catalyst according to claim 2, characterized in that The specific surface area is 80m 2 / g or above.

4. The nickel diatomaceous earth catalyst according to any one of claims 1 to 3, characterized in that The bond energy of Zr is more than 0.4 eV higher than that of ZrO2.

5. A method for producing a nickel diatomite catalyst, characterized in that: The production method is a method for producing a catalyst for hydrogenating aldehydes, and the production method comprises: An acidic aqueous solution preparation step to obtain an acidic aqueous solution in which Ni and Zr are dissolved; An alkaline suspension preparation step to obtain an alkaline suspension in which at least one of NaOH and Na2CO3 is dissolved and diatomaceous earth is dispersed; A neutralization step, adding the acidic aqueous solution to the alkaline suspension to obtain a mixed solution; A aging step, adjusting the pH of the mixed solution to below 6.5 and maintaining the pH for more than 30 minutes; A further aging step, wherein the pH of the mixed solution obtained in the aging step is adjusted to a range of 8.5 to 9.5 and maintained for more than 60 minutes to obtain a precursor slurry; A separation step of separating the precursor from the precursor slurry; The precursor is fired in a firing step.

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