CN114192162A

CN114192162A - Dimethyl benzyl alcohol hydrogenolysis catalyst and preparation method and application thereof

Info

Publication number: CN114192162A
Application number: CN202111522871.6A
Authority: CN
Inventors: 李作金; 詹吉山; 于海波; 沙宇; 孙康; 王同济; 叶飞; 王雷雷; 蒙萌; 王勤隆; 黎源
Original assignee: Wanhua Chemical Group Co Ltd
Current assignee: Wanhua Chemical Group Co Ltd
Priority date: 2021-12-13
Filing date: 2021-12-13
Publication date: 2022-03-18
Anticipated expiration: 2041-12-13
Also published as: CN114192162B

Abstract

The invention provides a dimethyl benzyl alcohol hydrogenolysis catalyst and a preparation method and application thereof, wherein the active components of the dimethyl benzyl alcohol hydrogenolysis catalyst comprise Pd, Ru, Cu and Ni, the Pd and the Ru in the active components are highly dispersed on the surface layer of the catalyst, so that the generation of side reactions such as excessive hydrogenation and the like can be inhibited, the dimethyl benzyl alcohol diffused to the inside of the pore channel of the catalyst can generate hydrogenolysis reaction under the catalysis of Cu and Ni to generate isopropylbenzene, but is difficult to be further hydrogenated to generate a byproduct isopropylcyclohexane; the carrier of the dimethyl benzyl alcohol hydrogenolysis catalyst comprises ZnO and SiO₂And Al₂O₃The composite carrier is beneficial to obtaining the high-efficiency hydrogenolysis catalyst with highly dispersed active components, reliable strength and moderate acidity; the dimethyl benzyl alcohol hydrogenolysis catalyst has the advantages of high dispersion degree of active components, smooth catalyst pore channel and the like, and has excellent activity and selectivity when being used for preparing isopropyl benzene by the hydrogenolysis of dimethyl benzyl alcohol.

Description

Dimethyl benzyl alcohol hydrogenolysis catalyst and preparation method and application thereof

Technical Field

The invention relates to the technical field of hydrogenolysis catalysts, and particularly relates to a dimethylbenzyl alcohol hydrogenolysis catalyst and a preparation method and application thereof.

Background

Industrial processes for the production of Propylene Oxide (PO) include mainly chlorohydrin process, direct oxidation of hydrogen peroxide process and co-oxidation process (Halcon process). The chlorohydrin method is a main route for producing PO at present, and the process has the problems of serious equipment corrosion, environmental pollution and the like. The direct hydrogen peroxide oxidation route suffers from high raw material cost and economic impact. The co-oxidation process is a process in which an organic peroxide and propylene are reacted to produce propylene oxide. Although the traditional isobutane co-oxidation method and the ethylbenzene co-oxidation method avoid serious pollution of a chlorohydrin method with high investment and long process flow to the environment, a large amount of byproducts are co-produced in the PO production process, and the production cost of PO is greatly influenced by the price fluctuation of co-products.

The cumene co-oxidation method (PO-CHP process) comprises three core reactions of cumene peroxidation, propylene epoxidation and dimethyl benzyl alcohol hydrogenolysis and related separation procedures, wherein cumene hydroperoxide is used as an oxygen source, the coproduced dimethyl benzyl alcohol is subjected to hydrogenolysis to generate the cumene, the cumene returns to a peroxidation unit to react to obtain the cumene hydroperoxide, and the cumene is recycled. Compared with other processes, the cumene co-oxidation method has the advantages of high conversion rate and selectivity, short process route, less equipment investment, no coproduct, more stable economic benefit and the like.

The dimethylbenzyl alcohol hydrogenolysis reaction is one of the core reactions of the PO-CHP process. The dimethylbenzyl alcohol hydrogenolysis catalyst mainly comprises a platinum-palladium noble metal catalyst, a nickel-based catalyst, a copper-based catalyst and the like, and is reported in many patents.

US3337646 provides a method for preparing isopropylbenzene by gas phase hydrogenolysis of alpha, alpha-dimethyl benzyl alcohol, which adopts Ni-Cr-Al₂O₃The catalyst contains Cr, and has serious environmental pollution problems in the preparation, use and recovery treatment processes of the catalyst.

Patent CN1308273C discloses a method for preparing cumene by catalytic hydrogenolysis of alpha, alpha-dimethylbenzyl alcohol, which adopts 2 wt% of Pd-C catalyst, the cost of the catalyst is high, and substances such as halogenated aromatic hydrocarbon, sodium formate, formic acid, indole and the like need to be introduced during the reaction, thereby increasing the separation difficulty and the cost.

Patent CN104230640A discloses a method for preparing isopropylbenzene by hydrogenolysis of alpha, alpha-dimethyl benzyl alcohol, which adopts Mg/Ca/Ba modified Pd-Ni/SiO₂The selectivity of the catalyst for generating the isopropyl benzene by hydrogenolysis reaction is generally less than 98.5 percent, the cost of the catalyst is high, and the selectivity is low.

Patent CN104874406 discloses a Pt-loaded hydrogenolysis catalyst, which takes phenolic resin-based activated carbon as a carrier, the catalyst preparation process is complex, the amplification preparation difficulty is large, the catalyst selectivity is obviously reduced after the catalyst is operated for 300 hours, and the catalyst stability is poor.

Patent CN1257138C proposes to use H₂The method of reducing Cu catalyst with CO mixture gas still uses Cu-Cr catalyst, and the patent does not disclose the stability index of catalyst.

Patent CN101992098 discloses a Cu-Zn-Al catalyst for preparing isopropylbenzene by hydrogenolysis of dimethyl benzyl alcohol, and the space velocity adopted by the patent is 1.5h^-1The space velocity is low and the patent does not disclose the use of a catalystThe latter state and the catalyst strength.

Patent CN112569930A discloses a preparation method of isopropyl benzene and the obtained isopropyl benzene, wherein Pd and a carbon-containing precursor are loaded on an alumina carrier, the content of carbon residue after roasting is less than 1.5%, the loading amount of Pd is 0.5%, and the cost of the catalyst is high. Further, the patent does not mention the method of forming the catalyst and the state of the catalyst particles after the reaction.

When the conventional noble metal catalyst is used for the hydrogenolysis reaction of dimethyl benzyl alcohol, the defects of high catalyst cost, easy aromatic ring saturation, poor cumene selectivity and the like exist; the nickel-based and copper-based catalysts have the defects of low activity, poor selectivity, easy sintering, poor liquid resistance of the catalysts and the like.

At present, when the catalyst prepared by the prior art is used for preparing cumene by catalytic hydrogenolysis of dimethyl benzyl alcohol, the problems of high loading of noble metal Pt/Pd and the like, low activity, poor selectivity, poor high-temperature stability, poor liquid resistance and serious environmental pollution exist. Therefore, it is important to develop a hydrogenolysis catalyst having excellent hydrogenolysis reaction performance.

Disclosure of Invention

In order to solve the technical problems, the invention provides a dimethyl benzyl alcohol hydrogenolysis catalyst and a preparation method and application thereof, wherein the active components of the dimethyl benzyl alcohol hydrogenolysis catalyst comprise Pd, Ru, Cu and Ni, the Pd and the Ru in the active components are highly dispersed on the surface layer of the catalyst, so that the generation of side reactions such as excessive hydrogenation and the like can be inhibited, the dimethyl benzyl alcohol diffused to the inside of the pore channel of the catalyst can generate a hydrogenolysis reaction under the catalysis of Cu and Ni to generate isopropylbenzene, but is difficult to further hydrogenate to generate a byproduct of isopropylcyclohexane; the carrier of the dimethyl benzyl alcohol hydrogenolysis catalyst comprises ZnO and SiO₂And Al₂O₃The composite carrier is beneficial to obtaining the high-efficiency hydrogenolysis catalyst with highly dispersed active components, reliable strength and moderate acidity; the dimethyl benzyl alcohol hydrogenolysis catalyst has the advantages of high dispersion degree of active components, smooth catalyst pore channel and the like, has excellent activity and selectivity when being used for preparing isopropyl benzene by the hydrogenolysis of dimethyl benzyl alcohol, and has good liquid resistance and high stability.

One of the purposes of the invention is to provide a dimethyl benzyl alcohol hydrogenolysis catalyst, wherein the total weight of the dimethyl benzyl alcohol hydrogenolysis catalyst is 100 wt%, and the dimethyl benzyl alcohol hydrogenolysis catalyst comprises the following components in percentage by weight of inorganic oxides:

the active components of the dimethyl benzyl alcohol hydrogenolysis catalyst comprise Pd, Ru, Cu and Ni, the Pd and the Ru in the active components are highly dispersed on the surface layer of the catalyst, so that the occurrence of side reactions such as excessive hydrogenation and the like can be inhibited, the dimethyl benzyl alcohol diffused to the inside of the pore channel of the catalyst can generate a hydrogenolysis reaction under the catalysis of Cu and Ni to generate isopropylbenzene, but is difficult to further hydrogenate to generate a byproduct of isopropylcyclohexane; the carrier of the dimethyl benzyl alcohol hydrogenolysis catalyst comprises ZnO and SiO₂And Al₂O₃The composite carrier is beneficial to obtaining the high-efficiency hydrogenolysis catalyst with highly dispersed active components, reliable strength and moderate acidity.

The dimethylbenzyl alcohol hydrogenolysis catalyst includes PdO 0.01 to 0.3 wt%, for example, 0.01 wt%, 0.05 wt%, 0.1 wt%, 0.15 wt%, 0.2 wt%, 0.25 wt%, or 0.3 wt%, etc., based on the total weight of the dimethylbenzyl alcohol hydrogenolysis catalyst being 100 wt% and calculated as an inorganic oxide, but is not limited to the enumerated values, and other unrecited values within the above-described range of values are also applicable.

The dimethylbenzyl alcohol hydrogenolysis catalyst comprises RuO (RuO) in an amount of inorganic oxide, wherein the total weight of the dimethylbenzyl alcohol hydrogenolysis catalyst is 100 wt%₂0.05 to 0.8 wt.%, for example 0.05 wt.%, 0.1 wt.%, 0.2 wt.%, 0.3 wt.%, 0.4 wt.%, 0.5 wt.%, 0.6 wt.%, 0.7 wt.% or 0.8 wt.%, etc., but not limited to the recited values, and other values not recited within the above-mentioned numerical ranges are equally applicable.

The dimethylbenzyl alcohol hydrogenolysis catalyst comprises CuO 15.0 to 25.0 wt%, for example, 15.0 wt%, 17.0 wt%, 19.0 wt%, 20.0 wt%, 21.0 wt%, 23.0 wt%, or 25.0 wt%, based on the total weight of the dimethylbenzyl alcohol hydrogenolysis catalyst taken as 100 wt% and calculated as the inorganic oxide, but is not limited to the recited values, and other values not recited in the above range of values are also applicable.

The dimethylbenzyl alcohol hydrogenolysis catalyst comprises 15.0 to 25.0 wt% ZnO, for example, 15.0 wt%, 17.0 wt%, 19.0 wt%, 20.0 wt%, 21.0 wt%, 23.0 wt%, or 25.0 wt%, based on the total weight of the dimethylbenzyl alcohol hydrogenolysis catalyst taken as 100 wt% and calculated as the inorganic oxide, but is not limited to the recited values, and other values not recited in the above range of values are also applicable.

The dimethylbenzyl alcohol hydrogenolysis catalyst comprises 2.0 to 10.0 wt% of NiO, such as 2.0 wt%, 4.0 wt%, 5.0 wt%, 6.0 wt%, 7.0 wt%, 8.0 wt%, or 10.0 wt%, based on the total weight of the dimethylbenzyl alcohol hydrogenolysis catalyst taken as 100 wt% and calculated as inorganic oxide, but is not limited to the recited values, and other values not recited within the above-mentioned range of values are also applicable.

The dimethyl benzyl alcohol hydrogenolysis catalyst comprises Al, wherein the weight percentage of the total weight of the dimethyl benzyl alcohol hydrogenolysis catalyst is 100 wt%, and the weight percentage is calculated by inorganic oxide₂O₃15.0 to 40.0 wt.%, for example 15.0 wt.%, 20.0 wt.%, 25.0 wt.%, 30.0 wt.%, 35.0 wt.% or 40.0 wt.%, etc., but not limited to the recited values, and other values not recited within the above-mentioned range of values are also applicable.

The dimethyl benzyl alcohol hydrogenolysis catalyst comprises SiO in terms of inorganic oxide, and the total weight of the dimethyl benzyl alcohol hydrogenolysis catalyst is 100wt percent₂20.0 to 45.0 wt.%, for example 20.0 wt.%, 25.0 wt.%, 30.0 wt.%, 35.0 wt.%, 40.0 wt.% or 45.0 wt.%, etc., but not limited to the recited values, and other values not recited within the above-mentioned range of values are also applicable.

In the preferred technical scheme of the invention, in the dimethylbenzyl alcohol hydrogenolysis catalyst, the molar ratio of Pd to Ru is 1 (1-10), the molar ratio of Cu to Zn is 1 (0.5-1.0), and the molar ratio of Cu to Ni is 1 (0.1-0.5).

In the dimethyl benzyl alcohol hydrogenolysis catalyst, the molar ratio of Pd to Ru is 1 (1-10), when the content of Pd is higher and the content of Ru is lower, the catalyst is higher in cost and serious in over-hydrogenation, and when the content of Pd is lower and the content of Ru is higher, the activity of the catalyst is insufficient; the molar ratio of Cu to Zn is 1 (0.5-1.0), the molar ratio of Cu to Ni is 1 (0.1-0.5), when the content of Cu is higher, the dispersion degree of Cu is poor, but the activity of the catalyst is influenced, and when the content of Cu is lower, the activity of the catalyst is insufficient; zn with proper content is introduced into the catalyst, so that the dispersion degree of Cu can be obviously improved; the catalyst activity is high but the selectivity is poor when the Ni content is high, and the catalyst activity is low when the Ni content is low. Therefore, the appropriate contents of Pd, Ru, Cu, Ni and Zn are advantageous for obtaining a hydrogenolysis catalyst with high activity and selectivity.

In a preferred embodiment of the present invention, the dimethylbenzyl alcohol hydrogenolysis catalyst has a hollow ring shape, an outer diameter of 3 to 5mm, for example, 3mm, 3.5mm, 4mm, 4.5mm or 5mm, and an inner diameter of 1 to 3mm, for example, 1mm, 1.5mm, 2mm, 2.5mm or 3mm, and a length of 3 to 8mm, for example, 3mm, 4mm, 5mm, 6mm, 7mm or 8mm, but the catalyst is not limited to the above-mentioned values, and other values not listed in the above-mentioned value range are also applicable.

The dimethylbenzyl alcohol hydrogenolysis catalyst is in a hollow ring shape, so that the mass transfer performance of the catalyst can be improved, the occurrence of side reactions is reduced, and the bed pressure drop is lower.

The second purpose of the present invention is to provide a method for preparing the dimethylbenzyl alcohol hydrogenolysis catalyst, which comprises the following steps:

(1) preparing a mixed solution 1 of a copper-containing compound, a zinc-containing compound and a nickel-containing compound; adding silica sol into urea aqueous solution to obtain mixed solution 2; adding an aminosilane coupling agent into the nano silicon dioxide alcoholic solution to obtain a mixed solution 3; preparing a mixed solution 4 containing a palladium compound and a ruthenium compound;

(2) adding the mixed solution 1 into the mixed solution 2, sequentially stirring, evaporating to dryness and roasting, and mixing the obtained composite metal compound, alumina powder and an extrusion aid to obtain mixed powder;

(3) dropwise adding the mixed solution 4 into the mixed solution 3 to obtain a mixed solution 5;

(4) adding the mixed powder in the step (2) into the mixed solution 5 in the step (3), and sequentially mixing, extruding, molding, drying and roasting to obtain a dimethyl benzyl alcohol hydrogenolysis catalyst;

wherein, the steps (2) and (3) are not in sequence.

The preparation method of the invention firstly prepares the composite metal compound containing copper, zinc and nickel, and then mixes the composite metal compound with alumina powder and extrusion aid to obtain mixed powder, so that active components Cu and Ni can be uniformly dispersed in ZnO and SiO₂And Al₂O₃The dimethyl benzyl alcohol diffused to the inside of the catalyst pore channel can generate the cumene through the hydrogenolysis reaction under the catalysis of Cu and Ni, but the side product of the isopropyl cyclohexane is difficult to generate through further hydrogenation; and then sequentially mixing, extruding and molding, drying and roasting the impregnation liquid (mixed solution 5) containing Pd and Ru and the mixed powder to ensure that Pd and Ru in the active component are highly dispersed on the surface layer of the catalyst, thereby being beneficial to inhibiting the occurrence of side reactions such as excessive hydrogenation and the like.

In addition, the preparation method of the invention mainly limits the preparation process of the mixed solution 5, namely, the mixed solution 4 containing the palladium compound and the ruthenium compound is dripped into the nano-silica alcoholic solution (the mixed solution 3) containing the amino silane coupling agent, and the nano-silica alcoholic solution is adopted to be beneficial to the high dispersion of palladium and ruthenium.

Furthermore, the preparation method of the invention is used for SiO in the composite carrier₂Two sources are provided, namely, the silica sol in the mixed solution 2, the nano-silica alcoholic solution in the mixed solution 3 and the SiO introduced in the form of the alkaline silica sol₂In the catalyst SiO₂20-40 wt% of the total amount, the silica sol in the mixed solution 2 can promote the dispersion of Cu, Zn and Ni, and the nano-silica alcoholic solution in the mixed solution 3 can improve the dispersion degree of Pd and Ru, and the Pd and the Ru supplement each other and are beneficial to improving the activity of the hydrogenolysis catalyst.

As a preferred technical solution of the present invention, in the mixed solution 1 in the step (1), the copper-containing compound includes copper formate and/or copper acetate.

Preferably, in the mixed solution 1 of step (1), the zinc-containing compound includes zinc formate and/or zinc acetate.

Preferably, in the mixed solution 1 of the step (1), the nickel-containing compound includes nickel formate and/or nickel acetate.

Preferably, in the mixed solution 1 of step (1), the molar concentration of the metal ion is 1.0-2.0mol/L, such as 1.0mol/L, 1.1mol/L, 1.3mol/L, 1.5mol/L, 1.7mol/L, 1.9mol/L, or 2.0mol/L, but not limited to the recited values, and other values not recited in the above-mentioned range of values are also applicable.

According to the invention, the mixed solution 1 adopts metal formate and/or metal acetate as raw materials, so that the subsequent reaction of the metal salt in the mixed solution 1 and the urea in the mixed solution 2 is facilitated to obtain slurry, the slurry is not required to be washed, and the slurry can be directly evaporated to dryness and roasted; in addition, formate and/or acetate can be decomposed by heating in the roasting process, so that the porosity of the dimethyl benzyl alcohol hydrogenolysis catalyst can be improved, and the mass transfer performance of the dimethyl benzyl alcohol hydrogenolysis catalyst can be improved.

Preferably, the mass concentration of the aqueous urea solution in step (1) is 15-30 wt%, such as 15 wt%, 18 wt%, 20 wt%, 23 wt%, 25 wt%, 26 wt%, 28 wt% or 30 wt%, etc., but not limited to the recited values, and other values not recited within the above-mentioned range of values are also applicable.

Preferably, the silica sol of step (1) is an alkaline silica sol.

Preferably, the SiO of the alkaline silica sol₂In an amount of 30 to 40 wt.%, e.g., 30 wt.%, 31 wt.%, 33 wt.%, 35 wt.%, 38 wt.% or 40 wt.%, with a particle size of 20 to 40nm, e.g., 20nm, 25nm, 30nm, 35nm or 40nm, and a pH of 8.0 to 10.0, e.g., 8.0, 8.5, 9.0, 9.5 or 10.0, but not limited to the recited values, and other values not recited within the above-mentioned numerical ranges are equally applicable.

Preferably, in the nano-silica alcoholic solution in the step (1), SiO₂In an amount of 15 to 20 wt.%, e.g., 15 wt.%, 16 wt.%, 17 wt.%, 18 wt.%, 19 wt.% or 20 wt.%, and the like, and a particle size of 15 to 30nm, e.g., 15nm, 18nm, 20nm, 23nm, 25nm, 28nm or 30nm, and the like, but is not limited to the recited values, and the above-mentioned ranges are within the rangeValues not listed by him are equally applicable.

The preparation method adopts the alcoholic solution of the nano silicon dioxide to be beneficial to the high dispersion of Pd and Ru; further limiting SiO in the nano-silicon dioxide alcoholic solution₂The content is 15-20 wt%, which can avoid SiO in the nano silicon dioxide alcohol solution₂When the content is too high, the dispersion of Pd and Ru is not favorable, and SiO can be avoided₂When the content is too low, the molding of the catalyst is not facilitated, and the strength of the molded catalyst may be lowered.

Preferably, the alcoholic solvent of the nanosilica alcoholic solution of step (1) comprises any one of methanol, ethanol or propanol or a combination of at least two of said combinations, typical but non-limiting examples of which include: a combination of methanol and ethanol, a combination of methanol and propanol, or a combination of ethanol and propanol, etc.

As a preferred technical solution of the present invention, the aminosilane coupling agent in step (1) comprises any one of or a combination of at least two of gamma-aminopropyltrimethoxysilane, gamma-aminopropyltriethoxysilane, anilinomethyltrimethoxysilane and anilinomethyltriethoxysilane, and typical but non-limiting examples of the combination include: a combination of gamma-aminopropyltrimethoxysilane and gamma-aminopropyltriethoxysilane, a combination of gamma-aminopropyltriethoxysilane and anilinomethyltrimethoxysilane, or a combination of anilinomethyltrimethoxysilane and anilinomethyltriethoxysilane, and the like.

Preferably, the mass ratio of the aminosilane coupling agent to the nanosilicon alcohol solution during the preparation of the mixed solution 3 in the step (1) is controlled to be 1 (20-50), for example, 1:20, 1:25, 1:30, 1:35, 1:40, 1:45, or 1:50, but not limited to the recited values, and other values not recited in the above range of values are also applicable.

According to the preparation method, the aminosilane coupling agent is added, so that the dispersion degree of Pd and Ru can be improved, the hydrogenolysis reaction activity of dimethyl benzyl alcohol is improved, unfavorable substances such as water generated in the reaction and the like are weakened to a certain extent, the damage to active components and a carrier is reduced, and the stability of the catalyst is facilitated; the mass ratio of the amino silane coupling agent to the nano silicon dioxide alcoholic solution is further limited to be 1 (20-50), so that the phenomenon that when the addition amount of the amino silane coupling agent is too small, the effect of improving the dispersion degree of Pd and Ru is not achieved, and when the addition amount of the amino silane coupling agent is too large, the phenomenon that the raw materials and products are not diffused is avoided.

Preferably, in the mixed solution 4 in the step (1), the palladium-containing compound includes palladium acetylacetonate.

Preferably, in the mixed solution 4 of step (1), the ruthenium-containing compound includes ruthenium acetylacetonate.

According to the preparation method, palladium acetylacetonate and ruthenium acetylacetonate are respectively used as a palladium source and a ruthenium source, and compared with palladium chloride/palladium nitrate and ruthenium chloride/ruthenium nitrate, the preparation method is more favorable for improving the dispersion degree of Pd and Ru, and further improves the reaction activity of the dimethyl benzyl alcohol hydrogenolysis catalyst.

Preferably, the solvent of the mixed solution 4 of step (1) includes any one of benzene, toluene or chloroform or a combination of at least two thereof, typical but non-limiting examples of which include: a combination of benzene and toluene, a combination of toluene and chloroform, or a combination of benzene and chloroform, etc.

In the step (2), the ratio of the number of moles of metal ions in the mixed solution 1 to the number of moles of urea in the mixed solution 2 is controlled to be 1 (2.0 to 3.0), for example, 1:2.0, 1:2.2, 1:2.4, 1:2.5, 1:2.7, 1:2.9, or 1:3.0, but the present invention is not limited to the above-mentioned values, and other values not listed in the above-mentioned value range are also applicable.

The preparation method limits the dosage of the urea, not only can avoid the disadvantages that the increase of the porosity of the catalyst is not facilitated when the dosage of the urea is too small, but also can avoid the disadvantages that the bulk density of the catalyst is smaller and the number of active bits on the catalyst per unit volume is lower when the dosage of the urea is too large.

Preferably, the temperature for evaporating in step (2) is 80-100 deg.C, such as 80 deg.C, 85 deg.C, 90 deg.C, 95 deg.C or 100 deg.C, but not limited to the recited values, and other values not recited in the above-mentioned range of values are also applicable.

Preferably, the time for evaporating to dryness in step (2) is 4-24h, such as 4h, 8h, 12h, 16h, 20h or 24h, but not limited to the recited values, and other values not recited in the above-mentioned value range are also applicable.

Preferably, the temperature of the calcination in step (2) is 250-400 ℃, such as 250 ℃, 280 ℃, 300 ℃, 320 ℃, 350 ℃, 380 ℃ or 400 ℃, but not limited to the recited values, and other unrecited values within the above-mentioned range of values are also applicable.

Preferably, the calcination time in step (2) is 2-8h, such as 2h, 3h, 4h, 5h, 6h, 7h or 8h, but not limited to the recited values, and other values not recited in the above range of values are also applicable.

In a preferred embodiment of the present invention, the alumina powder in the step (2) has a particle size of 80 to 150 mesh, for example, 80 mesh, 90 mesh, 100 mesh, 110 mesh, 120 mesh, 130 mesh, 140 mesh, or 150 mesh, but is not limited to the above-mentioned values, and other values not listed in the above-mentioned range of values are also applicable.

The preparation method of the invention adds alumina powder with proper granularity, which can avoid the disadvantage of alumina dispersion when the alumina powder is too coarse and the disadvantage of diffusion performance of the formed catalyst when the alumina powder is too fine.

Preferably, the alumina powder in step (2) is used in an amount of 15 to 40 wt%, such as 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, or 40 wt%, based on the sum of the mass of the composite metal compound and the mass of the alumina powder, but not limited to the recited values, and other unrecited values within the above-mentioned range of values are also applicable.

The preparation method provided by the invention can provide proper acidity for the catalyst by adding the alumina powder with proper content, so that not only can the problem of insufficient activity of the catalyst caused by less acidic sites be avoided, but also the problem of dehydration polymerization of dimethyl benzyl alcohol caused by excessive acidic sites and further the influence on the selectivity of the catalyst can be avoided.

Preferably, the extrusion aid in the step (2) comprises sesbania powder.

Preferably, the extrusion aid in step (2) is used in an amount of 2-5 wt%, such as 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, or 5 wt%, based on the mass sum of the composite metal compound and the alumina powder, but not limited to the recited values, and other values not recited in the above-mentioned range of values are also applicable.

As a preferable technical solution of the present invention, the extrusion molding process conditions in the step (4) include: fully kneading various materials for molding, and performing extrusion molding by adopting an F-26 twin-screw extruder at room temperature.

Preferably, the extrusion pressure of the extrusion molding is 100-200N, such as 100N, 120N, 150N, 180N or 200N, etc., and the screw rotation speed is 10-50r/min, such as 10r/min, 20r/min, 30r/min, 40r/min or 50r/min, etc., but not limited to the recited values, and other unrecited values within the above-mentioned range of values are also applicable.

Preferably, the drying temperature in step (4) is 100-120 ℃, such as 100 ℃, 105 ℃, 110 ℃, 115 ℃ or 120 ℃, but not limited to the recited values, and other unrecited values within the above-mentioned range of values are equally applicable.

Preferably, the drying time in step (4) is 4-12h, such as 4h, 8h, 12h, 16h, 20h or 24h, but not limited to the recited values, and other values not recited in the above numerical range are also applicable.

Preferably, the temperature of the calcination in step (4) is 300-450 deg.C, such as 300 deg.C, 330 deg.C, 350 deg.C, 380 deg.C, 400 deg.C, 430 deg.C or 450 deg.C, but is not limited to the recited values, and other values not recited in the above-mentioned range of values are also applicable.

Preferably, the calcination time in step (4) is 2-8h, such as 2h, 3h, 4h, 5h, 6h, 7h or 8h, but not limited to the recited values, and other values not recited in the above range of values are also applicable.

As a preferred technical scheme of the invention, the preparation method comprises the following steps:

(1) preparing a solution:

preparing a mixed solution 1 of a copper-containing compound, a zinc-containing compound and a nickel-containing compound; wherein the copper-containing compound comprises copper formate and/or copper acetate, the zinc-containing compound comprises zinc formate and/or zinc acetate, and the nickel-containing compound comprises nickel formate and/or nickel acetate; the molar concentration of metal ions in the mixed solution 1 is 1.0-2.0 mol/L;

adding alkaline silica sol into a urea aqueous solution with the mass concentration of 15-30 wt% to obtain a mixed solution 2; wherein the SiO of the alkaline silica sol₂30-40 wt%, particle size of 20-40nm, and pH of 8.0-10.0;

adding an aminosilane coupling agent into a nano-silica alcoholic solution, and controlling the mass ratio of the aminosilane coupling agent to the nano-silica alcoholic solution to be 1 (20-50) to obtain a mixed solution 3; wherein, in the nano silicon dioxide alcoholic solution, SiO₂15-20 wt% of the active carbon, and the particle size is 15-30 nm; the alcoholic solvent of the nano-silica alcoholic solution comprises any one or the combination of at least two of methanol, ethanol or propanol; the amino silane coupling agent comprises any one or the combination of at least two of gamma-aminopropyl trimethoxy silane, gamma-aminopropyl triethoxy silane, aniline methyl trimethoxy silane and aniline methyl triethoxy silane;

preparing a mixed solution 4 containing a palladium compound and a ruthenium compound; wherein the palladium-containing compound comprises palladium acetylacetonate, the ruthenium-containing compound comprises ruthenium acetylacetonate, and the solvent of the mixed solution 4 comprises any one of benzene, toluene or chloroform or a combination of at least two of the benzene, the toluene or the chloroform;

(2) adding the mixed solution 1 into the mixed solution 2, stirring, controlling the ratio of the mole number of metal ions in the mixed solution 1 to the mole number of urea in the mixed solution 2 to be 1 (2.0-3.0), evaporating to dryness at 80-100 ℃ for 4-24h, roasting at 250-400 ℃ for 2-8h, and mixing the obtained composite metal compound with alumina powder with the particle size of 80-150 meshes and an extrusion aid to obtain mixed powder; wherein the amount of the alumina powder accounts for 15-40 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder, and the amount of the extrusion aid accounts for 2-5 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder;

(4) adding the mixed powder in the step (2) into the mixed solution 5 in the step (3) for stirring, fully kneading various materials for molding, performing extrusion molding by adopting an F-26 double-screw extruder at room temperature, controlling the extrusion pressure of the extrusion molding to be 100-;

wherein, the steps (2) and (3) are not in sequence.

The third purpose of the present invention is to provide an application of the dimethylbenzyl alcohol hydrogenolysis catalyst, wherein the dimethylbenzyl alcohol hydrogenolysis catalyst prepared by the first purpose or the second purpose preparation method is applied to a reaction for preparing cumene by dimethylbenzyl alcohol hydrogenolysis, and a specific process is referred to CN 104230642B.

Compared with the prior art, the invention has at least the following beneficial effects:

the dimethyl benzyl alcohol hydrogenolysis catalyst has the advantages of high dispersion degree of active components, smooth catalyst pore channel and the like, has excellent activity and selectivity when being used for preparing isopropyl benzene by the hydrogenolysis of dimethyl benzyl alcohol, and has good liquid resistance and high stability.

Detailed Description

For the purpose of facilitating an understanding of the present invention, the present invention will now be described by way of examples. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.

< sources of raw materials >

Cumene, purchased from Shanghai Allantin Biotechnology GmbH;

dimethylbenzyl alcohol, available from echiicai chemical synthesis industries development limited;

sodium silica sol, available from linyi cohn silicon products, ltd;

palladium acetylacetonate, available from Shanghai Allantin Biotechnology Ltd;

ruthenium acetylacetonate, available from Shanghai Allantin Biotechnology Ltd;

copper formate, available from Shanghai Allantin Biotechnology, Inc.;

zinc formate, available from Shanghai Allantin Biotechnology, Inc.;

nickel formate, available from Shanghai Allantin Biotechnology, Inc.;

urea, available from shanghai alatin biochem technologies, ltd;

alcohol solutions of silicon dioxide, Xuancheng crystal material, ltd;

alumina powder, available from Shanghai Aladdin Biotechnology GmbH.

< test methods >

1. Analyzing the composition of the dimethyl benzyl alcohol hydrogenolysis catalyst by adopting an X-ray fluorescence spectrometer (XRF);

2. conversion of dimethylbenzyl alcohol (1-mole of dimethylbenzyl alcohol remaining in reaction solution/mole of dimethylbenzyl alcohol contained in raw material) × 100%;

cumene selectivity-100% moles of cumene formed/moles dimethylbenzyl alcohol converted;

wherein, the mole number of dimethyl benzyl alcohol contained in the raw material, the mole number of generated isopropyl benzene and the mole number of the dimethyl benzyl alcohol remained in the reaction solution are calculated after being analyzed by an Agilent 7820A gas chromatograph, and the test conditions comprise: adopts DB-5 chromatographic column and FID detector, the vaporizing chamber temperature is 260 deg.C, the detector temperature is 260 deg.C, and the carrier gas is high-purity N₂The flow rate was 30 ml/min.

Example 1

This example provides a preparation method of a dimethylbenzyl alcohol hydrogenolysis catalyst, which includes the following steps:

(1) preparing a solution:

672.4g of water is added into a reaction kettle, 96.4g of copper formate, 24.7g of nickel formate and 85.6g of zinc formate are added, and the mixture is fully stirred and dissolved to obtain a mixed solution 1;

an aqueous urea solution was obtained by dissolving 133.3g of urea in 755.2g of water, and then 78.0g of alkaline silica Sol (SiO) was added₂Content 30 wt%, particle size 30nm, pH 9.0) and sufficiently stirring to obtain a mixed solution 2;

11.6g of gamma-aminopropyltrimethoxysilane were added to 253.5g of nanosilica ethanol Solution (SiO)₂20 wt% in a particle size of 30nm), and sufficiently stirring to obtain a mixed solution 3;

dissolving 0.5g of palladium acetylacetonate and 4.2g of ruthenium acetylacetonate in 93.8g of benzene, and sufficiently stirring to obtain a mixed solution 4;

(2) adding the mixed solution 1 into the mixed solution 2, stirring, evaporating to dryness at 95 ℃ for 12 hours, roasting at 300 ℃ for 6 hours, and mixing the obtained composite metal compound, 40.0g of alumina powder with the particle size of 100 meshes and 4.3g of sesbania powder to obtain mixed powder; wherein the amount of the alumina powder accounts for 27.8 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder, and the amount of the extrusion aid accounts for 3.0 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder;

(4) adding the mixed powder in the step (2) into the mixed solution 5 in the step (3) for stirring, fully kneading various materials for molding, performing extrusion molding by adopting an F-26 double-screw extruder at room temperature, controlling the extrusion pressure of the extrusion molding to be 150N, controlling the screw rotation speed to be 30r/min, drying at 110 ℃ for 4h, and then roasting at 450 ℃ for 4h to obtain a dimethylbenzyl alcohol hydrogenolysis catalyst A;

wherein, the steps (2) and (3) are not in sequence.

Analysis by X-ray fluorescence spectroscopy (XRF) of catalyst a composition (in inorganic oxides): PdO 0.10 wt%, RuO₂ 0.70wt％，CuO 17.0wt％，NiO 5.0wt％，ZnO 18.2wt％，Al₂O₃ 20.0wt％，SiO₂ 39.0wt％。

And (3) catalyst reduction:

the catalyst A is arranged in a fixed bed hydrogenation reactor,the catalyst loading was 100 ml. Before the catalyst is used, the catalyst is reduced under the mixed gas of nitrogen and hydrogen, and the volume space velocity of the mixed gas is kept for 300h in the reduction process^-1Firstly, the temperature of the reactor is raised to 160 ℃, the temperature is kept constant for 2 hours, the physical water absorbed by the catalyst is removed, and then H with the volume fraction of 5v percent is introduced₂The mixed gas of hydrogen and nitrogen is pre-reduced for 1h, then the proportion of hydrogen in the mixed gas of hydrogen and nitrogen is gradually increased to 10 v%, 20 v%, 50 v% and 100%, the temperature of the hot spot of the catalyst bed layer in the process is controlled not to exceed 250 ℃, and finally the temperature is increased to 250 ℃ to be reduced for 4h under the pure hydrogen atmosphere.

Evaluation of catalyst Performance:

the raw material is 25 wt% of isopropyl benzene solution of dimethyl benzyl alcohol, and the isopropyl benzene solution is prepared at the pressure of 2.0MPa, the temperature of 150 ℃ and the H₂The mol ratio of alcohol to alcohol is 8:1, and the liquid hourly space velocity is 3h^-1The reaction is carried out under the conditions of (1). The results of the hydrogenolysis reaction are shown in Table 1.

Example 2

(1) preparing a solution:

672.4g of water is added into a reaction kettle, and then 124.8g of copper formate, 12.4g of nickel formate and 75.0g of zinc formate are added, and the mixture is fully stirred and dissolved to obtain a mixed solution 1;

145.9g of urea was dissolved in 583.5g of water to obtain an aqueous urea solution, and 83.6g of alkaline silica Sol (SiO)₂40 wt%, particle size 40nm, pH 9.0) and fully stirring to obtain a mixed solution 2;

6.5g of gamma-aminopropyltriethoxysilane was added to 264.0g of nanosilica ethanol Solution (SiO)₂20 wt% in a particle size of 30nm), and sufficiently stirring to obtain a mixed solution 3;

dissolving 0.75g of palladium acetylacetonate and 2.4g of ruthenium acetylacetonate in 62.8g of benzene, and sufficiently stirring to obtain a mixed solution 4;

(2) adding the mixed solution 1 into the mixed solution 2, stirring, evaporating to dryness at 99 ℃ for 12 hours, then roasting at 350 ℃ for 4 hours, and mixing the obtained composite metal compound, 30.0g of alumina powder with the particle size of 100 meshes and 4.3g of sesbania powder to obtain mixed powder; wherein the amount of the alumina powder accounts for 20.8 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder, and the amount of the extrusion aid accounts for 3.0 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder;

(4) adding the mixed powder in the step (2) into the mixed solution 5 in the step (3) for stirring, fully kneading various materials for molding, performing extrusion molding by adopting an F-26 double-screw extruder at room temperature, controlling the extrusion pressure of the extrusion molding to be 150N, controlling the screw rotation speed to be 30r/min, drying at 110 ℃ for 8h, and then roasting at 400 ℃ for 4h to obtain a dimethylbenzyl alcohol hydrogenolysis catalyst which is marked as a catalyst B;

wherein, the steps (2) and (3) are not in sequence.

Analysis by X-ray fluorescence spectroscopy (XRF) of catalyst B composition (in inorganic oxides): PdO 0.15 wt%, RuO₂ 0.40wt％，CuO 22.0wt％，NiO 2.5wt％，ZnO 15.95wt％，Al₂O₃ 15.0wt％，SiO₂ 44.0wt％。

The catalyst B was subjected to a catalyst reduction test and catalyst performance evaluation, the specific process conditions and operation were as in example 1, and the results of the hydrogenolysis reaction are shown in Table 1.

Example 3

(1) preparing a solution:

750.3g of water is firstly added into a reaction kettle, and then 113.5g of copper formate, 39.6g of nickel formate and 78.2g of zinc formate are added, and the mixture is fully stirred and dissolved to obtain a mixed solution 1;

189.3g of urea was dissolved in 441.6g of water to obtain an aqueous urea solution, and 70.0g of alkaline silica Sol (SiO) was added thereto₂Content 30 wt%, particle size 30nm, pH 9.0) and sufficiently stirring to obtain a mixed solution 2;

6.8g of anilinomethyltrimethoxysilane are added to 248.0g of Nanosilicone propanol Solution (SiO)₂Content of 15 wt% and particle size of 30nm), and fully stirring to obtain a mixed solution 3;

dissolving 0.90g of palladium acetylacetonate and 1.2g of ruthenium acetylacetonate in 41.9g of chloroform, and sufficiently stirring to obtain a mixed solution 4;

(2) adding the mixed solution 1 into the mixed solution 2, stirring, evaporating to dryness at 95 ℃ for 12h, then roasting at 300 ℃ for 8h, and mixing the obtained composite metal compound with 50.0g of alumina powder with the particle size of 100 meshes and 4.8g of sesbania powder to obtain mixed powder; wherein the amount of the alumina powder accounts for 31.2 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder, and the amount of the extrusion aid accounts for 3.0 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder;

(4) adding the mixed powder in the step (2) into the mixed solution 5 in the step (3) for stirring, fully kneading various materials for molding, performing extrusion molding by adopting an F-26 double-screw extruder at room temperature, controlling the extrusion pressure of the extrusion molding to be 150N, controlling the screw rotation speed to be 30r/min, drying at 110 ℃ for 12h, and then roasting at 400 ℃ for 8h to obtain a dimethylbenzyl alcohol hydrogenolysis catalyst which is marked as a catalyst C;

wherein, the steps (2) and (3) are not in sequence.

Analysis by X-ray fluorescence spectroscopy (XRF) of catalyst C composition (in inorganic oxides): PdO 0.18 wt%, RuO₂ 0.20wt％，CuO 20.0wt％，NiO 8wt％，ZnO 16.62wt％，Al₂O₃25.0wt％，SiO₂30.0wt％。

The catalyst C was subjected to a catalyst reduction test and catalyst performance evaluation, the specific process conditions and operation were as in example 1, and the results of the hydrogenolysis reaction are shown in table 1.

Example 4

(1) preparing a solution:

725.4g of water is added into a reaction kettle, and then 141.8g of copper formate, 14.8g of nickel formate and 72.6g of zinc formate are added, and the mixture is fully stirred and dissolved to obtain a mixed solution 1;

169.9g of urea was dissolved in 509.7g of water to give an aqueous urea solution, after which 26.3g of alkaline silica Sol (SiO)₂40 wt%, particle size 30nm, pH 9.0) and fully stirring to obtain a mixed solution 2;

9.4g of aniline methyl triethoxysilane was added to 196.0g of nanosilica ethanol Solution (SiO)₂Content of 15 wt% and particle size of 30nm), and fully stirring to obtain a mixed solution 3;

dissolving 0.60g of palladium acetylacetonate and 2.7g of ruthenium acetylacetonate in 65.8g of benzene, and sufficiently stirring to obtain a mixed solution 4;

(2) adding the mixed solution 1 into the mixed solution 2, stirring, evaporating to dryness at 90 ℃ for 12 hours, roasting at 400 ℃ for 4 hours, and mixing the obtained composite metal compound, 70.0g of alumina powder with the particle size of 100 meshes and 5.0g of sesbania powder to obtain mixed powder; wherein the amount of the alumina powder accounts for 41.8 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder, and the amount of the extrusion aid accounts for 3.0 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder;

(4) adding the mixed powder in the step (2) into the mixed solution 5 in the step (3) for stirring, fully kneading various materials for molding, performing extrusion molding by adopting an F-26 double-screw extruder at room temperature, controlling the extrusion pressure of the extrusion molding to be 150N, controlling the screw rotation speed to be 30r/min, drying at 120 ℃ for 4h, and then roasting at 450 ℃ for 6h to obtain a dimethylbenzyl alcohol hydrogenolysis catalyst which is marked as a catalyst D;

wherein, the steps (2) and (3) are not in sequence.

Analysis by X-ray fluorescence spectroscopy (XRF) of catalyst D composition (in inorganic oxides): PdO 0.12 wt%, RuO₂ 0.45wt％，CuO 25.0wt％，NiO 3wt％，ZnO 15.43wt％，Al₂O₃ 35.0wt％，SiO₂ 21.0wt％。

The catalyst D was subjected to a catalyst reduction test and a catalyst performance evaluation, the specific process conditions and the operation were as in example 1, and the results of the hydrogenolysis reaction are shown in Table 1.

Example 5

(1) preparing a solution:

774.6g of water is added into a reaction kettle, 130.5g of copper formate, 24.7g of nickel formate and 86.1g of zinc formate are added, and a mixed solution 1 is obtained after full stirring and dissolution;

160.5g of urea was dissolved in 642.0g of water to give an aqueous urea solution, after which 30.7g of alkaline silica Sol (SiO)₂Content of 30 wt%, particle size of 40nm, pH of 9.0) and sufficiently stirring to obtain a mixed solution 2;

9.6g of gamma-aminopropyltrimethoxysilane were added to 223.9g of a nanosilica ethanol Solution (SiO)₂Content of 15 wt% and particle size of 30nm), and fully stirring to obtain a mixed solution 3;

dissolving 1.0g of palladium acetylacetonate and 3.0g of ruthenium acetylacetonate in 79.8g of benzene, and sufficiently stirring to obtain a mixed solution 4;

(2) adding the mixed solution 1 into the mixed solution 2, stirring, evaporating to dryness at 95 ℃ for 12h, then roasting at 300 ℃ for 8h, and mixing the obtained composite metal compound with 60.0g of alumina powder with the particle size of 100 meshes and 4.9g of sesbania powder to obtain mixed powder; wherein the amount of the alumina powder accounts for 37.1 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder, and the amount of the extrusion aid accounts for 3.0 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder;

(4) adding the mixed powder in the step (2) into the mixed solution 5 in the step (3) for stirring, fully kneading various materials for molding, performing extrusion molding by adopting an F-26 double-screw extruder at room temperature, controlling the extrusion pressure of the extrusion molding to be 150N, controlling the screw rotation speed to be 30r/min, drying at 120 ℃ for 8h, and then roasting at 350 ℃ for 8h to obtain a dimethylbenzyl alcohol hydrogenolysis catalyst which is marked as a catalyst E;

wherein, the steps (2) and (3) are not in sequence.

Analysis by X-ray fluorescence spectroscopy (XRF) of catalyst E composition (in inorganic oxides): PdO 0.2 wt%, RuO₂ 0.5wt％，CuO 23.0wt％，NiO 5.0wt％，ZnO 18.3wt％，Al₂O₃ 30.0wt％，SiO₂23.0wt％。

The catalyst E was subjected to a catalyst reduction test and a catalyst performance evaluation, the specific process conditions and the operation were as in example 1, and the results of the hydrogenolysis reaction are shown in Table 1.

Example 6

(1) preparing a solution:

644.1g of water is added into a reaction kettle, 102.1g of copper formate, 19.8g of nickel formate and 77.8g of zinc formate are added, and the mixture is fully stirred and dissolved to obtain a mixed solution 1;

156.7g of urea were dissolved in 470.0g of water to give an aqueous urea solution, after which 32.2g of alkaline silica Sol (SiO)₂40 wt%, particle size 40nm, pH 9.0) and fully stirring to obtain a mixed solution 2;

6.8g of gamma-aminopropyltriethoxysilane was added to 208.5g of nanosilica propanol Solution (SiO)₂Content of 15 wt% and particle size of 30nm), and fully stirring to obtain a mixed solution 3;

dissolving 0.8g of palladium acetylacetonate and 1.8g of ruthenium acetylacetonate in 51.9g of chloroform, and sufficiently stirring to obtain a mixed solution 4;

(2) adding the mixed solution 1 into the mixed solution 2, stirring, evaporating to dryness at 90 ℃ for 12 hours, then roasting at 400 ℃ for 8 hours, and mixing the obtained composite metal compound with 76.0g of alumina powder with the particle size of 100 meshes and 5.0g of sesbania powder to obtain mixed powder; wherein the amount of the alumina powder accounts for 45.8 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder, and the amount of the extrusion aid accounts for 3.0 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder;

(4) adding the mixed powder in the step (2) into the mixed solution 5 in the step (3) for stirring, fully kneading various materials for molding, performing extrusion molding by adopting an F-26 double-screw extruder at room temperature, controlling the extrusion pressure of the extrusion molding to be 150N, controlling the screw rotation speed to be 30r/min, drying at 100 ℃ for 12h, and then roasting at 400 ℃ for 4h to obtain a dimethylbenzyl alcohol hydrogenolysis catalyst which is marked as a catalyst F;

wherein, the steps (2) and (3) are not in sequence.

Analysis by X-ray fluorescence spectroscopy (XRF) of catalyst F composition (in inorganic oxides): PdO 0.16 wt%, RuO₂ 0.3wt％，CuO 18.0wt％，NiO 4.0wt％，ZnO 16.54wt％，Al₂O₃ 38.0wt％，SiO₂ 23.0wt％。

The catalyst F was subjected to a catalyst reduction test and a catalyst performance evaluation, the specific process conditions and the operation were as in example 1, and the results of the hydrogenolysis reaction are shown in Table 1.

Comparative example 1

This comparative example provides a method for preparing a dimethylbenzyl alcohol hydrogenolysis catalyst, with reference to example 1, the only difference being that: the step (1) does not use urea aqueous solution, i.e., the mixed solution 2 is alkaline silica Sol (SiO)₂30 wt%, particle size of 30nm, pH of 9.0); the resulting dimethylbenzyl alcohol hydrogenolysis catalyst was designated as catalyst G.

The catalyst G was subjected to catalyst reduction test and catalyst performance evaluation, the specific process conditions and operation were as in example 1, and the results of hydrogenolysis reaction are shown in table 1.

Comparative example 2

This comparative example provides a method for preparing a dimethylbenzyl alcohol hydrogenolysis catalyst, with reference to example 2, the only difference being that: alumina powder is not used in the step (2), namely, the obtained composite metal compound is directly mixed with 4.3g of sesbania powder to obtain mixed powder; the resulting dimethylbenzyl alcohol hydrogenolysis catalyst was designated as catalyst H.

The catalyst H was subjected to a catalyst reduction test and evaluation of catalyst performance, the specific process conditions and operation were as in example 1, and the results of hydrogenolysis reaction are shown in Table 1.

Comparative example 3

This comparative example provides a method for preparing a dimethylbenzyl alcohol hydrogenolysis catalyst, with reference to example 3, the only difference being that: aminosilane coupling agent (aniline methyl trimethoxy silane) is not used in the step (1), namely, the mixed solution 3 is nano silicon dioxide propanol Solution (SiO)₂15 wt% of the powder and 30nm in particle size); the resulting dimethylbenzyl alcohol hydrogenolysis catalyst was designated as catalyst I.

The catalyst I was subjected to catalyst reduction test and catalyst performance evaluation, the specific process conditions and operation were as in example 1, and the results of hydrogenolysis reaction are shown in Table 1.

Comparative example 4

This comparative example provides a method for preparing a dimethylbenzyl alcohol hydrogenolysis catalyst, see example 4, with the only difference that: step (1) does not use nano silicon dioxide ethanol Solution (SiO)₂Content of 15 wt% and particle diameter of 30nm), and mixing the alkaline silica Sol (SiO) of step (1)₂40 wt%, particle size 30nm, pH 9.0) from 26.3g to 99.8 g; the resulting dimethylbenzyl alcohol hydrogenolysis catalyst was designated as catalyst J.

The catalyst J was subjected to a catalyst reduction test and evaluation of catalyst performance, and the specific process conditions and operation were as in example 1, and the results of hydrogenolysis reaction are shown in table 1.

Comparative example 5

This comparative example provides a method for preparing a dimethylbenzyl alcohol hydrogenolysis catalyst, with reference to example 5, the only difference being that: palladium acetylacetonate is not used in the step (1), and ruthenium acetylacetonate with the same molar quantity is adopted for substitution, namely, 1.30g of ruthenium acetylacetonate is additionally added; the resulting dimethylbenzyl alcohol hydrogenolysis catalyst was designated as catalyst K.

The catalyst K was subjected to a catalyst reduction test and a catalyst performance evaluation, the specific process conditions and the operation were as in example 1, and the results of the hydrogenolysis reaction are shown in Table 1.

Comparative example 6

This comparative example provides a method for preparing a dimethylbenzyl alcohol hydrogenolysis catalyst, with reference to example 5, the only difference being that: step (1) does not use ruthenium acetylacetonate, and uses palladium acetylacetonate of the same molar quantity to substitute, namely, add palladium acetylacetonate of 2.30g in addition; the resulting dimethylbenzyl alcohol hydrogenolysis catalyst was designated as catalyst L.

The catalyst L was subjected to a catalyst reduction test and a catalyst performance evaluation, and the specific process conditions and the operation were as in example 1, and the results of the hydrogenolysis reaction are shown in table 1.

Comparative example 7

This comparative example provides a method of preparing a dimethylbenzyl alcohol hydrogenolysis catalyst, see example 6, with the only difference that: respectively replacing palladium acetylacetonate and ruthenium acetylacetonate with palladium chloride and ruthenium chloride in equal molar quantity, namely dissolving 0.46g of palladium chloride and 0.94g of ruthenium chloride in 28.0g of water, and fully stirring to obtain a mixed solution 4; the resulting dimethylbenzyl alcohol hydrogenolysis catalyst was designated as catalyst M.

The catalyst M was subjected to a catalyst reduction test and a catalyst performance evaluation, and specific process conditions and operation procedures were as in example 1, and the results of the hydrogenolysis reaction are shown in Table 1.

The results of the hydrogenolysis reaction for the catalysts prepared in the above examples and comparative examples are summarized in table 1 below.

TABLE 1

From table 1, the following points can be seen:

(1) the catalysts A-F obtained by the preparation method have good activity and selectivity, which shows that the catalyst for the hydrogenolysis of the dimethyl benzyl alcohol has high dispersion degree of active components and smooth catalyst pore passage, and has excellent activity and selectivity when being used for preparing isopropylbenzene by the hydrogenolysis of the dimethyl benzyl alcohol;

(2) through comparison between the example 1 and the comparative example 1, the urea is added in the preparation process of the dimethylbenzyl alcohol hydrogenolysis catalyst, so that the mass transfer performance of the catalyst can be improved, and the reaction activity and selectivity can be improved;

(3) by comparing example 2 with comparative example 2, it is shown that the absence of alumina powder in the preparation of the dimethylbenzyl alcohol hydrogenolysis catalyst results in a weaker acidity of the catalyst, which is not favorable for the conversion of dimethylbenzyl alcohol, and a lower activity of the catalyst;

(4) comparison between example 3 and comparative example 3 shows that addition of an aminosilane coupling agent in the preparation process of the dimethylbenzyl alcohol hydrogenolysis catalyst is helpful for improving the dispersion degree of noble metals, and further improving the reaction conversion rate;

(5) by comparing example 4 with comparative example 4, it is shown that adding nano-sized silica alcohol solution during the preparation of the dimethylbenzyl alcohol hydrogenolysis catalyst helps to improve the hydrogenolysis reaction activity of the catalyst;

(6) by comparing example 5 with comparative examples 5 and 6, it is shown that only Ru or only Pd as the noble metal active component in the dimethylbenzyl alcohol hydrogenolysis catalyst can cause lower hydrogenolysis activity, and excessive Pd content can promote excessive hydrogenation side reaction;

(7) by comparing example 6 with comparative example 6, it is demonstrated that palladium acetylacetonate and ruthenium acetylacetonate are preferred as the noble metal palladium source and ruthenium source in the dimethylbenzyl alcohol hydrogenolysis catalyst, which is beneficial to improving the dispersion degree of Pd and Ru, and further improving the reaction activity of the dimethylbenzyl alcohol hydrogenolysis catalyst.

The present invention is illustrated by the above-mentioned examples, but the present invention is not limited to the above-mentioned detailed process equipment and process flow, i.e. it is not meant to imply that the present invention must rely on the above-mentioned detailed process equipment and process flow to be practiced. It should be understood by those skilled in the art that any modification of the present invention, equivalent substitutions of the raw materials of the product of the present invention, addition of auxiliary components, selection of specific modes, etc., are within the scope and disclosure of the present invention.

Claims

1. The dimethyl benzyl alcohol hydrogenolysis catalyst is characterized by comprising the following components in percentage by weight based on the total weight of the dimethyl benzyl alcohol hydrogenolysis catalyst being 100 wt% and calculated by inorganic oxides:

2. the dimethylbenzyl alcohol hydrogenolysis catalyst of claim 1 wherein the dimethylbenzyl alcohol hydrogenolysis catalyst comprises a molar ratio of Pd to Ru of 1 (1-10), a molar ratio of Cu to Zn of 1 (0.5-1.0), and a molar ratio of Cu to Ni of 1 (0.1-0.5);

preferably, the dimethylbenzyl alcohol hydrogenolysis catalyst is in a hollow ring shape, the outer diameter is 3-5mm, the inner diameter is 1-3mm, and the length is 3-8 mm.

3. A preparation method for preparing the dimethylbenzyl alcohol hydrogenolysis catalyst as claimed in claim 1 or 2, comprising the steps of:

wherein, the steps (2) and (3) are not in sequence.

4. The production method according to claim 3, wherein, in the mixed solution 1 in the step (1), the copper-containing compound includes copper formate and/or copper acetate;

preferably, in the mixed solution 1 of step (1), the zinc-containing compound includes zinc formate and/or zinc acetate;

preferably, in the mixed solution 1 of the step (1), the nickel-containing compound includes nickel formate and/or nickel acetate;

preferably, in the mixed solution 1 in the step (1), the molar concentration of the metal ions is 1.0-2.0 mol/L;

preferably, the mass concentration of the urea aqueous solution in the step (1) is 15-30 wt%;

preferably, the silica sol of step (1) is an alkaline silica sol;

preferably, the SiO of the alkaline silica sol₂30-40 wt%, particle size of 20-40nm, and pH of 8.0-10.0;

preferably, in the nano-silica alcoholic solution in the step (1), SiO₂15-20 wt% of the active carbon, and the particle size is 15-30 nm;

preferably, the alcoholic solvent of the nanosilica alcoholic solution of step (1) comprises any one of methanol, ethanol or propanol or a combination of at least two thereof.

5. The method according to claim 3 or 4, wherein the aminosilane coupling agent of step (1) comprises any one of or a combination of at least two of γ -aminopropyltrimethoxysilane, γ -aminopropyltriethoxysilane, anilinomethyltrimethoxysilane, anilinomethyltriethoxysilane;

preferably, in the preparation process of the mixed solution 3 in the step (1), the mass ratio of the aminosilane coupling agent to the nano-silica alcohol solution is controlled to be 1 (20-50);

preferably, in the mixed solution 4 in the step (1), the palladium-containing compound includes palladium acetylacetonate;

preferably, in the mixed solution 4 of step (1), the ruthenium-containing compound includes ruthenium acetylacetonate;

preferably, the solvent of the mixed solution 4 in the step (1) comprises any one or a combination of at least two of benzene, toluene or chloroform.

6. The production method according to any one of claims 3 to 5, wherein in the step (2), the ratio of the number of moles of the metal ions in the mixed solution 1 to the number of moles of the urea in the mixed solution 2 is controlled to 1 (2.0 to 3.0);

preferably, the temperature for evaporating in the step (2) is 80-100 ℃;

preferably, the time for evaporating in the step (2) is 4-24 h;

preferably, the roasting temperature in the step (2) is 250-400 ℃;

preferably, the roasting time of the step (2) is 2-8 h.

7. The production method according to any one of claims 3 to 6, wherein the particle size of the alumina powder of step (2) is 80 to 150 mesh;

preferably, the amount of the alumina powder in the step (2) is 15-40 wt% of the sum of the mass of the composite metal compound and the mass of the alumina powder;

preferably, the extrusion aid in the step (2) comprises sesbania powder;

preferably, the extrusion aid in the step (2) is used in an amount of 2-5 wt% of the total mass of the composite metal compound and the alumina powder.

8. The production method according to any one of claims 3 to 7, wherein the extrusion molding process conditions of step (4) include: fully kneading various materials used for molding, and performing extrusion molding by adopting an F-26 twin-screw extruder at room temperature;

preferably, the extrusion pressure of the extrusion molding is 100-200N, and the screw rotation speed is 10-50 r/min;

preferably, the temperature for drying in step (4) is 100-120 ℃;

preferably, the drying time of the step (4) is 4-12 h;

preferably, the roasting temperature in the step (4) is 300-450 ℃;

preferably, the roasting time of the step (4) is 2-8 h.

9. The method according to any one of claims 3 to 8, characterized by comprising the steps of:

(1) preparing a solution:

wherein, the steps (2) and (3) are not in sequence.

10. The use of a dimethylbenzyl alcohol hydrogenolysis catalyst, characterized in that the dimethylbenzyl alcohol hydrogenolysis catalyst according to claim 1 or 2 or the dimethylbenzyl alcohol hydrogenolysis catalyst prepared by the preparation method according to any one of claims 3 to 9 is used in a reaction for preparing cumene by dimethylbenzyl alcohol hydrogenolysis.