CN114507123B

CN114507123B - Preparation method of 2-alkyl cyclohexanone homolog

Info

Publication number: CN114507123B
Application number: CN202011288013.5A
Authority: CN
Inventors: 孙承林; 薛伟洋; 顾彬; 李敬美; 吴慧玲; 刘梦洋
Original assignee: Dalian Institute of Chemical Physics of CAS
Current assignee: Dalian Institute of Chemical Physics of CAS
Priority date: 2020-11-17
Filing date: 2020-11-17
Publication date: 2023-10-10
Anticipated expiration: 2040-11-17
Also published as: CN114507123A

Abstract

The application discloses a preparation method of a 2-alkyl cyclohexanone homolog, which comprises the steps of carrying out contact reaction on a raw material containing fatty aldehyde and cyclohexanone and/or cyclohexanone homolog with a catalyst in a reaction vessel with hydrogen atmosphere to obtain the 2-alkyl cyclohexanone homolog. The catalyst is alkaline active components and hydrogenation active components loaded by porous alkaline oxide. The catalyst has the double active centers of solid alkali and hydrogenation metal, can catalyze fatty aldehyde and cyclohexanone containing carbonyl alpha-H to prepare 2-alkyl cyclohexanone homologue through aldol condensation and hydrogenation one-step method, has the advantages of high raw material conversion rate, good product selectivity, multiple use of the catalyst and environmental protection, does not need to adjust reaction temperature and pressure in the reaction process, is simple and safe to operate, and has good application prospect.

Description

Preparation method of 2-alkyl cyclohexanone homolog

Technical Field

The application relates to a preparation method of a 2-alkyl cyclohexanone homolog, belonging to the field of perfume synthesis.

Background

The 2-alkylcyclohexanone homolog is an important fine chemical intermediate that can be used to prepare a number of important downstream products. For example, 2-butylcyclohexanone can be sequentially subjected to Baeyer-Villiger oxidation, saponification and dehydration reaction to prepare the milk lactone, which is an important spice and has milk fragrance, can be used for preparing various types of essences such as milk, cream, yoghurt, strawberries and the like, and has wide application. At present, the method for synthesizing 2-butylcyclohexanone reported in the literature comprises the following steps: 1) Cyclohexanone is used as a raw material, and is subjected to a series of deprotonation and bromoalkane hydrolysis under the action of N-methyl hydrazine and the catalysis of trifluoroacetic acid; 2) From suberic acid, decarboxylation is carried out through esterification, condensation, alkylation and hydrolysis; 3) N-butyraldehyde and cyclohexanone are used as starting materials, and aldol condensation and hydrogenation reduction are carried out. Wherein, the process for preparing 2-butylcyclohexanone by aldol condensation and selective hydrogenation of n-butyraldehyde and cyclohexanone is practical, raw materials are easy to obtain, and the method is the most main synthesis method. The traditional alkyl cyclohexanone synthesis method represented by 2-butyl cyclohexanone is a two-step method, firstly, aldehyde and cyclohexanone homologues are subjected to aldol condensation reaction under the action of alkaline water, and the separated condensation product is subjected to selective catalytic hydrogenation to obtain the alkyl cyclohexanone.

For example, the Chinese patent application publication No. CN1266841A discloses that n-butyraldehyde and cyclohexanone are used as raw materials, sodium hydroxide is added into a reaction system to catalyze aldol condensation, pd/C catalyst is added after extractive distillation to prepare 2-butylcyclohexanone by selective hydrogenation step reaction, and the step reaction requires purification, and the addition of sodium hydroxide complicates the post-treatment of the product, so that the cost of the whole synthesis route is high, more sewage is generated, and the catalyst is difficult to recycle.

Chinese patent application publication No. CN109651128A and CN109678699A both disclose continuous production methods of milk lactone, which comprise aldol condensation reaction under the condition of alkaline water, hydrogenation reaction, oxidation ring expansion, acid continuous hydrolysis and dehydration to obtain milk lactone spice product.

Chinese patent application publication CN103864601a discloses a method for obtaining 2-butylcyclohexanone by performing alkaline condensation on n-butyraldehyde and cyclohexanone as raw materials under the action of a phase transfer catalyst, and catalytic hydrogenation after dehydration, but still requires to react in NaOH solution.

However, the two-step method has complicated steps, high cost of a synthetic route, low yield of products, difficult recovery of the catalyst, and serious environmental pollution, and can generate a large amount of alkaline wastewater. Therefore, the solid alkali is developed as a catalytic center, and the catalytic aldol condensation reaction has economic value and environmental protection significance.

For example, chinese patent No. CN102019177B discloses a method for aldol condensation of a composite material loaded with at least one basic metal oxide, which uses a composite oxide as a carrier, thereby avoiding the use of an alkaline aqueous solution, reducing the treatment and emission of organic wastewater, and having excellent catalytic performance for aldol condensation reaction.

For example, chinese patent No. CN101205170B discloses the use of alumina-based solid catalysts to support alkali or alkaline earth metal oxides and transition metal oxides to catalyze the self-condensation of cyclohexanone.

However, since the solid alkali used in the above application has a lower alkali strength than the liquid alkali, resulting in a slower aldol condensation reaction rate, the solid alkali catalyzed condensation reaction often requires a higher temperature to obtain a high reaction rate, and at the same time, the condensation reaction rate is significantly decreased due to a decrease in the raw material ratio and an increase in the condensation product ratio with the progress of the reaction, the side reaction is increased, and the selectivity is decreased, which is very important for developing a new green synthesis process and a new catalyst for alkylcyclohexanone.

Disclosure of Invention

Aiming at the defects of the existing synthesis method of the 2-alkyl cyclohexanone homologue, the application provides a novel synthesis method of the 2-alkyl cyclohexanone homologue, and realizes the efficient, green, simple and safe synthesis of the 2-alkyl cyclohexanone homologue.

A preparation method of 2-alkyl cyclohexanone homolog, which comprises the steps of carrying out contact reaction on a raw material containing aliphatic aldehyde and cyclohexanone and/or cyclohexanone homolog with a catalyst in a closed reaction vessel with hydrogen atmosphere to obtain the 2-alkyl cyclohexanone homolog; the catalyst comprises a porous alkaline oxide carrier, an alkaline active component and a hydrogenation active component; the porous basic oxide carrier is at least one selected from zinc oxide, titanium oxide, zirconium oxide, aluminum oxide, na-ZSM-5, naY and Na-Beta molecular sieves; the alkaline active component contains alkaline active elements; the alkaline active element is selected from at least one of alkali metal element, alkaline earth metal element or rare earth metal element; the hydrogenation active component contains hydrogenation active elements; the hydrogenation active element is at least one selected from Pt element, pd element, ru element, rh element and Ni element.

In the present application, "cyclohexanone homologue" means cyclohexanone which may contain αh and has an alkyl substituent at the 2-6 position.

In the present application, "fatty aldehyde" means C ₃ -C ₁₁ Preferably C ₃ -C ₈ Is a monovalent saturated aldehyde.

As a preferred embodiment, the alkali metal element is selected from sodium and/or potassium elements; the alkaline earth metal element is at least one of calcium, magnesium or barium; the rare earth metal element is at least one selected from yttrium, lanthanum and cerium.

As a preferable technical scheme, in the catalyst, the content of the alkaline active component is 0.5-10%, and the content of the hydrogenation active component is 0.05-10%; wherein the content of the alkaline active component is calculated by the mass percentage of the alkaline active element contained in the alkaline active component; the content of the hydrogenation active component is calculated by the mass percentage of the hydrogenation active element contained in the hydrogenation active component;

preferably, the content of the hydrogenation active component is 0.1-2%, and the content of the alkaline active component is 0.5-5%;

preferably, the upper limit of the content of the hydrogenation-active component is selected from 0.1%, 0.2%, 0.5%, 1%, 1.5%, 2%, 2.5%, 5%, 7%, 9% or 10%; the lower limit is selected from 0.05%, 0.1%, 0.2%, 0.5%, 1%, 1.5%, 2%, 2.5%, 5%, 7% or 9%;

preferably, the upper limit of the alkaline active component content is selected from 1%, 1.5%, 2%, 3%, 5%, 6%, 7%, 8%, 9% or 10%; the lower limit is selected from 0.5%, 1%, 1.5%, 2%, 3%, 5%, 6%, 7%, 8% or 9%.

As a preferred technical scheme, the molar ratio of the cyclohexanone and/or cyclohexanone homologue to the fatty aldehyde is 1:1-10:1;

preferably, the molar ratio of cyclohexanone and/or cyclohexanone homologues to fatty aldehydes is from 2:1 to 5:1;

preferably, the upper limit of the molar ratio of cyclohexanone to aldehydes of the alpha-H containing cyclohexanone homolog is selected from 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1 or 10:1; the lower limit is selected from 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, or 9:1.

As a preferable technical scheme, the dosage of the catalyst is 0.5-15% of the total mass of the raw materials;

preferably, the dosage of the catalyst is 0.5-10% of the total mass of the raw materials;

preferably, the catalyst is used in an amount such that the upper limit of the total mass of the feedstock is selected from 0.8%, 0.83%, 1%, 2%, 3%, 5%, 6%, 7%, 8%, 9%, 10% or 15%; the lower limit is selected from 0.5%, 0.8%, 0.9%, 1%, 2%, 3%, 5%, 6%, 7%, 8%, 9% or 10%.

As a preferred technical scheme, the cyclohexanone homolog is a cyclohexanone homolog containing carbonyl alpha hydrogen;

preferably, the cyclohexanone homologue is selected from at least one of cyclohexanone, 2-ethylcyclohexanone, 3-propylcyclohexanone, 4-isopropylcyclohexanone or 4-methylcyclohexanone;

preferably, the fatty aldehyde is at least one selected from the group consisting of propionaldehyde, n-butyraldehyde, n-valeraldehyde, n-caproaldehyde, n-heptanal, n-caprylic aldehyde, isobutyraldehyde and n-isovaleraldehyde.

As a preferable technical scheme, the pressure of the hydrogen in the reaction vessel is 0.5-5.0 Mpa;

preferably, the pressure of the hydrogen in the reaction vessel is 1.0 to 4.0Mpa.

Preferably, the pressure of the hydrogen is 0.5-4.5 Mpa.

Preferably, the pressure of the hydrogen is 1.0-3.5 Mpa.

Preferably, the pressure of the hydrogen is 0.5-4 Mpa.

Preferably, the pressure of the hydrogen is 1.0-3.0 Mpa.

Preferably, the upper limit of the pressure of the hydrogen is selected from 1Mpa, 1.5Mpa, 2Mpa, 2.5Mpa, 3Mpa, 3.5Mpa, 4Mpa, 4.5Mpa or 5Mpa; the lower limit is selected from 0.5Mpa, 1Mpa, 1.5Mpa, 2Mpa, 2.5Mpa, 3Mpa, 3.5Mpa, 4Mpa or 4.5Mpa.

As a preferable technical scheme, the temperature of the reaction is 80-180 ℃;

preferably, the temperature of the reaction is 100 to 160 ℃.

Preferably, the upper limit of the temperature of the reaction is selected from 110 ℃, 120 ℃, 130 ℃, 140 ℃, 150 ℃, 160 ℃, 170 ℃ or 180 ℃; the lower limit is selected from 100 ℃, 110 ℃, 120 ℃, 130 ℃, 140 ℃, 150 ℃, 160 ℃ or 170 ℃.

Preferably, the reaction is terminated when the pressure of the hydrogen gas in the closed reaction vessel is no longer reduced.

In the application, along with the consumption of hydrogen in the actual reaction, the pressure of the hydrogen can be slowly reduced, the solvent can be subjected to self-condensation hydrogenation under the action of the catalyst, and the reaction degree can be determined by sampling in a kettle on line in a laboratory.

In another aspect of the application, a process for preparing a catalyst for preparing a 2-alkylcyclohexanone homolog is provided, comprising at least the steps of: the porous alkaline carrier or the precursor thereof is immersed in a solution containing alkaline active elements and hydrogenation active elements, and then dried and calcined to obtain the catalyst, wherein the soluble salt is preferably at least one of corresponding acetate, oxalate, nitrate or chloride.

The catalyst of the present application may be synthesized by conventional impregnation or co-precipitation to support noble metal (e.g., sun Chunhui, in sea bin, chen Yongsheng, xu Yan, liu Wei. Research on co-precipitation to prepare Ni/Al2O3 catalyst [ J ]. Inorganic salt industry, 2014,46 (11): 76-78. Research on co-precipitation to prepare Ni/Al2O3 catalyst).

As a specific embodiment, the process for preparing a 2-alkylcyclohexanone homolog comprises at least:

uniformly mixing a mixture containing fatty aldehyde, cyclohexanone homologue containing alpha H and a catalyst, and carrying out aldol condensation and hydrogenation reaction at the reaction temperature of 80-180 ℃ and the hydrogen pressure of 0.5-5.0 MPa to generate the 2-alkyl cyclohexanone homologue.

Alternatively, the reaction does not require any solvent.

The application has the beneficial effects that:

the preparation method of the 2-alkyl cyclohexanone homologue provided by the application catalyzes fatty aldehyde and alpha-H-containing cyclohexanone homologue to prepare the 2-alkyl cyclohexanone homologue by a one-step method, and adds alkali metal, alkaline earth metal or rare earth metal element auxiliary agents into a catalyst, and removes condensation products through hydrogenation reaction of coupling condensation products, so that the preparation of the 2-alkyl cyclohexanone homologue has the advantages of high raw material conversion rate, good selectivity, stable catalytic activity and environmental protection, low operation pressure, no need of adjusting reaction temperature and pressure in the reaction process, high raw material fatty aldehyde conversion rate of more than 90%, high 2-alkyl cyclohexanone homologue selectivity of more than 80%, and realization of efficient, green, simple and safe synthesis of the 2-alkyl cyclohexanone homologue, simple operation process and good application prospect.

Drawings

FIG. 1 is a bar graph of conversion and selectivity for Cat-29 of example 21 reused 10 times under the same conditions.

FIG. 2 is a nuclear magnetic resonance carbon spectrum of 2-butylcyclohexanone obtained by rectifying the product of example.

FIG. 3 is a nuclear magnetic resonance hydrogen spectrum of 2-butylcyclohexanone obtained by rectifying the product of example.

FIG. 4 is a bar graph of conversion and selectivity for Cat-40 of comparative example 3 reused 10 times under the same conditions.

Detailed Description

The present application is described in detail below with reference to examples, but the present application is not limited to these examples.

Unless otherwise indicated, all starting materials in the examples of the present application were purchased commercially. In the examples, the technical means used are conventional technical means in the art unless otherwise specified. In the examples, the test methods of the given apparatus all use the manufacturer recommended settings unless otherwise specified.

The analysis method in the embodiment of the application is as follows:

the composition of the product after the reaction was analyzed on an Agilent 7890 gas chromatograph, the selectivity of the product was calculated by peak area normalization using a DB-5 column and FID detector, and the conversion was calculated based on the consumption of fatty aldehyde.

Conversion and selectivity in the examples of the present application were calculated as follows, both based on the moles of fatty aldehyde.

i is a fatty aldehyde conversion product, and includes by-products such as fatty alcohols, fatty aldehyde self-condensation products, olefins and polymers thereof, in addition to the target product 2-alkylcyclohexanone homolog.

Example 1 catalyst preparation

Dissolving a certain amount of soluble salt corresponding to one or two of platinum, palladium, ruthenium, rhodium and nickel active components and a certain amount of soluble salt corresponding to one or two of potassium, sodium, magnesium, calcium, barium, yttrium, lanthanum and cerium auxiliary agents in deionized water to form uniform impregnating solution, respectively impregnating alkaline solid porous oxides such as zinc oxide, titanium oxide, zirconium oxide, aluminum oxide or sodium molecular sieve in the impregnating solution for a certain time, evaporating water in an oven at 80-120 ℃, roasting the obtained solid precursors at 450 ℃ to obtain 34 catalysts, namely Cat-1-Cat-34, and recording catalyst reaction raw materials and component compositions in table 1.

TABLE 1 composition of the catalyst obtained in example 1

Example 2 2 preparation of butylcyclohexanone

2.46g of Cat-1 to Cat-34 catalyst obtained in the example 1 are respectively weighed and added into a reaction kettle with 36g of cyclohexanone and 13.2g of n-butyraldehyde, after the reaction kettle is sealed, nitrogen is introduced to enable the air pressure of the reaction kettle to reach 0.2Mpa, the gas of the reaction kettle is discharged through an exhaust port, the reaction kettle is repeated three times, hydrogen is introduced again for 1Mpa, the exhaust is repeated three times again, the hydrogen of 2.5Mpa is introduced again, after the stirring is started and fully mixed, the temperature is raised to 140 ℃ until the reaction pressure in the kettle is not reduced, the reaction is finished, the reaction kettle is cooled, the exhaust and the filtered product and the liquid product are sequentially marked as Pro-1 to Pro34.

The conversion and selectivity to product are shown in Table 2.

Example 3 2 preparation of butylcyclohexanone

0.41g,2.95g and 4.92g of Cat-6 catalyst obtained in example 1 were weighed into a reaction vessel having 36g of cyclohexanone and 13.2g of n-butyraldehyde, respectively, and the rest was exactly the same as in example 2, and the obtained products were successively identified as Pro-35 to Pro-37, the conversion and the selectivity of the products, and the results are shown in Table 2.

Example 42 preparation of butylcyclohexanone

0.94g of Cat-6 catalyst obtained in example 1 was weighed into a reaction vessel having 18g of cyclohexanone and 13.2g of n-butyraldehyde, and the rest of the operation was exactly the same as in example 2, and the obtained product was designated Pro-38.

Example 52 preparation of butylcyclohexanone

3.1g of Cat-6 catalyst obtained in example 1 was weighed into a reaction vessel having 90g of cyclohexanone and 13.2g of n-butyraldehyde, and the rest of the operation was exactly the same as in example 2, and the obtained product was designated Pro-39.

Example 6 2 preparation of butylcyclohexanone

5.8g of Cat-6 catalyst obtained in example 1 was weighed into a reaction vessel having 180g of cyclohexanone and 13.2g of n-butyraldehyde, and the rest of the operation was exactly the same as in example 2, and the obtained product was designated Pro-40.

Example 7 2 preparation of butylcyclohexanone

2.46g of Cat-6 catalyst obtained in example 1 was weighed into a reaction vessel having 36g of cyclohexanone and 13.2g of n-butyraldehyde, the reaction temperature was 100℃and the rest of the operation was exactly the same as in example 2, and the obtained product was designated Pro-41.

Example 82 preparation of butylcyclohexanone

2.46g of Cat-6 catalyst obtained in example 1 was weighed into a reaction vessel having 36g of cyclohexanone and 13.2g of n-butyraldehyde, the reaction temperature was 160℃and the rest of the operation was exactly the same as in example 2, and the obtained product was designated Pro-42.

Example 92 preparation of butylcyclohexanone

2.46g of Cat-6 catalyst obtained in example 1 was weighed into a reaction vessel having 36g of cyclohexanone and 13.2g of n-butyraldehyde, the reaction temperature was 180℃and the rest of the operation was exactly the same as in example 2, and the obtained product was designated Pro-43.

Example 10 preparation of 2-butylcyclohexanone

2.46g of Cat-6 catalyst obtained in example 1 was weighed into a reaction vessel having 36g of cyclohexanone and 13.2g of n-butyraldehyde, the reaction pressure was 0.5MPa, and the other operations were exactly the same as in example 7, and the obtained product was designated Pro-44.

Example 11 preparation of 2-butylcyclohexanone

2.46g of Cat-6 catalyst obtained in example 1 was weighed into a reaction vessel having 36g of cyclohexanone and 13.2g of n-butyraldehyde, the reaction pressure was 1.0MPa, and the other operations were exactly the same as in example 7, and the obtained product was designated Pro-45.

Example 12 preparation of 2-butylcyclohexanone

2.46g of Cat-6 catalyst obtained in example 1 was weighed into a reaction vessel having 36g of cyclohexanone and 13.2g of n-butyraldehyde, the reaction pressure was 4.5MPa, and the other operations were exactly the same as in example 7, and the obtained product was designated Pro-46.

EXAMPLE 13 preparation of 2-propylcyclohexanone

2.46g of Cat-4 catalyst obtained in example 1 was weighed into a reaction vessel having 36g of cyclohexanone and 13.2g of n-propionaldehyde, and the rest of the operation was exactly the same as in example 2, and the obtained product was designated Pro-47 in turn.

EXAMPLE 14 preparation of 2-pentylcyclohexanone

2.46g of Cat-4 catalyst obtained in example 1 was weighed into a reaction vessel having 36g of cyclohexanone and 13.2g of n-valeraldehyde, and the rest of the operation was exactly the same as in example 2, and the obtained product was designated Pro-48 in turn.

Example 15 preparation of 2-hexyl cyclohexanone

2.46g of Cat-4 catalyst obtained in example 1 was weighed into a reaction vessel having 36g of cyclohexanone and 13.2g of n-hexanal, and the rest was exactly the same as in example 2, and the obtained product was designated Pro-49 in turn.

EXAMPLE 16 preparation of 2-heptyl Cyclohexanone

2.46g of Cat-4 catalyst obtained in example 1 was weighed into a reaction vessel having 36g of cyclohexanone and 13.2g of n-heptanal, and the rest of the operation was exactly the same as in example 2, and the obtained product was designated Pro-50 in turn.

EXAMPLE 17 preparation of 2-octyl cyclohexanone

2.46g of Cat-4 catalyst obtained in example 1 was weighed into a reaction vessel having 36g of cyclohexanone and 13.2g of n-octanal, and the rest was exactly the same as in example 2, and the obtained product was designated Pro-51 in turn.

EXAMPLE 18 preparation of 2-isobutyl Cyclohexanone

2.46g of Cat-4 catalyst obtained in example 1 was weighed into a reaction vessel having 36g of cyclohexanone and 13.2g of isobutyraldehyde, and the rest of the operation was exactly the same as in example 2, and the obtained product was designated Pro-52 in turn.

Example 19 preparation of 2-butyl, 6-ethylcyclohexanone

2.46g of Cat-4 catalyst obtained in example 1 was weighed into a reaction vessel having 36g of 2-ethylcyclohexanone and 13.2g of n-butyraldehyde, and the rest of the procedure was exactly the same as in example 2, and the obtained product was designated Pro-53 in turn.

EXAMPLE 20 preparation of 2-butyl, 4-isopropyl Cyclohexanone

2.46g of Cat-4 catalyst obtained in example 1 was weighed into a reaction vessel having 36g of 4-isopropylcyclohexanone and 13.2g of n-butyraldehyde, and the rest was exactly the same as in example 2, and the obtained product was designated Pro-54 in turn.

Example 21 Cat-29 stable repeatability experiment

2.46g of Cat-29 catalyst in example 1 is weighed and added into a reaction kettle with 36g of cyclohexanone and 13.2g of n-butyraldehyde, after the reaction kettle is sealed, nitrogen is introduced to ensure that the pressure of the reaction kettle reaches 0.2Mpa, the gas of the reaction kettle is discharged through a gas outlet and is repeated three times, hydrogen is introduced again for 1Mpa, the gas is discharged again for three times, hydrogen of 2.5Mpa is introduced again, stirring is started and fully mixed, the temperature is raised to 140 ℃, the temperature is kept constant until the reaction pressure in the kettle is not reduced, and the reaction is ended.

After cooling, venting and complete settling of the stationary catalyst, the liquid was removed and 36g cyclohexanone and 13.2g n-butyraldehyde were added and the above procedure repeated for a total of 10 experiments.

Analysis of the obtained products was designated Re-1 to Re-10, and the data are recorded in Table 3 and FIG. 1.

FIG. 1 shows that the catalyst prepared by the application not only has excellent single-pass reaction performance, but also has more stable recycling performance.

The nuclear magnetic resonance spectra in fig. 2 and 3 show nuclear magnetic resonance spectra corresponding to the target product, and do not show peaks of chemical shift values corresponding to carbon-carbon double bonds and hydroxyl groups, which indicates that the patent has excellent reaction performance for preparing 2-alkyl cyclohexanone homologs, such as 2-butylcyclohexanone.

Comparative example 1 alkali-free active ingredient

Dissolving a certain amount of soluble salt corresponding to one or two of active components of platinum, palladium, ruthenium, rhodium and nickel in deionized water to form uniform impregnation solution, respectively impregnating alkaline solid porous oxides such as zinc oxide, titanium oxide, zirconium oxide, aluminum oxide or sodium molecular sieve in the impregnation solution for a certain time, evaporating water in an oven at 80-120 ℃, and roasting the obtained solid precursors at 450 ℃ to obtain 5 catalysts, namely Cat-35-Cat-40, wherein the catalyst reaction raw materials and the component compositions are listed in Table 2.

TABLE 2 composition of the catalyst obtained in comparative example 1

Catalyst numbering	Reaction raw materials	Composition (mass percent)
			Cat-35	0.1334g of chloroplatinic acid, 10g of zinc oxide	0.5％Pt
Cat-36	0.1334g of chloroplatinic acid, 10g of titanium oxide	0.5％Pt
			Cat-37	0.1334g of chloroplatinic acid, 10g of zirconia	0.5％Pt
Cat-38	0.1334g of chloroplatinic acid, 10g of alumina	0.5％Pt
			Cat-39	0.1334g of chloroplatinic acid, 10g of Na-ZSM-5	0.5％Pt
Cat-40	0.0882g of palladium chloride, 10g of alumina	0.5％Pd

Comparative example 2 2 preparation of butylcyclohexanone

2.46g of Cat-35 to Cat-39 catalyst obtained in comparative example 1 are respectively weighed and added into a reaction kettle with 36g of cyclohexanone and 13.2g of n-butyraldehyde, after the reaction kettle is sealed, nitrogen is introduced to enable the air pressure of the reaction kettle to reach 0.2Mpa, the gas of the reaction kettle is discharged through an exhaust port, the reaction kettle is repeated three times, hydrogen is introduced again for 1Mpa, the exhaust is repeated three times again, the hydrogen of 2.5Mpa is introduced again, after stirring is started and fully mixed, the temperature is raised to 140 ℃ until the reaction pressure in the kettle is not reduced, the reaction is finished, cooling, the exhaust and the filtered product are sequentially marked as Pro-55 to Pro59.

Comparative example 3 Cat-40 stable repeatability experiment

2.46g of Cat-40 catalyst in comparative example 1 is weighed and added into a reaction kettle with 36g of cyclohexanone and 13.2g of n-butyraldehyde, after the reaction kettle is sealed, nitrogen is introduced to ensure that the pressure of the reaction kettle reaches 0.2Mpa, the gas of the reaction kettle is discharged through a gas outlet, the reaction is repeated for three times, hydrogen is introduced again for 1Mpa, the gas is discharged again for three times, the hydrogen is filled again for 2.5Mpa, after stirring is started and fully mixed, the temperature is raised to 140 ℃, the temperature is kept constant until the reaction pressure in the kettle is not reduced, and the reaction is ended.

The analysis of the resulting product was recorded as ARe-1 to ARe-10 and the data are recorded in Table 3 and FIG. 4.

Fig. 1 and 4 are pairs of views illustrating that the stability of the catalysts prepared according to the present application is significantly higher than that of single oxides such as alumina supported catalysts. The reason is presumed to be that the hydrothermal stability of a single oxide such as alumina is generally poor, and it is reported that the presence of water affects the activity and stability of the catalyst, and that the reaction is a sealed water-producing reaction, and thus the catalyst is susceptible to water (e.g., tai, J. And R. J. Davis (2007), "Synthesis of methacrylic acid by aldol condensation of propionic acid with formaldehyde over acid-base bifunctional catalysts.," catalyst Today123 (1-4): 42-49).

The results of product analysis for the preparation of the 2-alkylcyclohexanone homolog are summarized in Table 3 below.

TABLE 3 analysis of reaction products

As can be seen from the data in Table 3, the synthesis method of the 2-alkyl cyclohexanone homologue provided by the application has the advantages of high raw material conversion rate, good product selectivity and environmental protection, and has good application prospect, and the reaction temperature and pressure do not need to be adjusted in the reaction process, so that the operation is simple and safe. Compared with catalyst Cat-55 to Cat-59 without addition agent, the aldehyde conversion rate of the catalyst with addition agent is more than 90%, the product selectivity is more than 80%, and the aldehyde conversion rate and the product selectivity of the catalyst without addition agent are far higher.

The catalyst has double active centers of solid alkali and hydrogenation metal, and can catalyze fatty aldehyde and cyclohexanone containing carbonyl alpha-H to prepare 2-alkyl cyclohexanone homologue by aldol condensation and hydrogenation one-step method.

While the application has been described in terms of preferred embodiments, it will be understood by those skilled in the art that various changes and modifications can be made without departing from the scope of the application, and it is intended that the application is not limited to the specific embodiments disclosed.

Claims

1. A process for producing a 2-alkylcyclohexanone homolog, characterized in that a raw material containing aliphatic aldehyde and cyclohexanone and/or cyclohexanone homolog is contacted with a catalyst in a reaction vessel having a hydrogen atmosphere to obtain the 2-alkylcyclohexanone homolog;

the catalyst comprises a porous alkaline oxide carrier, an alkaline active component and a hydrogenation active component;

the porous basic oxide carrier is at least one selected from zinc oxide, titanium oxide, zirconium oxide, aluminum oxide, na-ZSM-5, naY and Na-Beta molecular sieves;

the alkaline active component contains alkaline active elements; the alkaline active element is selected from at least one of alkali metal element, alkaline earth metal element or rare earth metal element;

the hydrogenation active component contains hydrogenation active elements; the hydrogenation active element is at least one selected from Pt element, pd element, ru element, rh element and Ni element;

in the catalyst, the content of alkaline active components is 0.5-10%, and the content of hydrogenation active components is 0.05-10%;

wherein the content of the alkaline active component is calculated by the mass percentage of the alkaline active element contained in the alkaline active component; the content of the hydrogenation active component is calculated by the mass percentage of the hydrogenation active element contained in the hydrogenation active component;

the dosage of the catalyst is 0.5-15% of the total mass of the raw materials;

the conversion rate of the reacted fatty aldehyde is more than 90%, and the selectivity of the 2-alkyl cyclohexanone homolog is more than 80%.

2. The method of manufacturing according to claim 1, characterized in that: the alkali metal element is selected from sodium and/or potassium elements;

the alkaline earth metal element is at least one of calcium, magnesium or barium; the rare earth metal element is at least one selected from yttrium, lanthanum and cerium.

3. The method of manufacturing according to claim 1, characterized in that:

the content of hydrogenation active components is 0.1% -2%, and the content of alkaline active components is 0.5% -5%.

4. The method of manufacturing according to claim 1, characterized in that: the molar ratio of the cyclohexanone and/or cyclohexanone homologue to the fatty aldehyde is 1:1-10:1.

5. The process according to claim 1, wherein the molar ratio of cyclohexanone and/or cyclohexanone homologues to fatty aldehydes is from 2:1 to 5:1.

6. The method of manufacturing according to claim 1, characterized in that:

the dosage of the catalyst is 0.5-10% of the total mass of the raw materials.

7. The method of manufacturing according to claim 1, characterized in that: the cyclohexanone homolog is a cyclohexanone homolog containing carbonyl alpha hydrogen.

8. The method of claim 1, wherein the cyclohexanone homolog is selected from at least one of cyclohexanone, 2-ethylcyclohexanone, 3-propylcyclohexanone, 4-isopropylcyclohexanone, or 4-methylcyclohexanone.

9. The method according to claim 1, wherein the fatty aldehyde is at least one selected from the group consisting of propionaldehyde, n-butyraldehyde, n-valeraldehyde, n-caproaldehyde, n-heptanal, n-octanal, isobutyraldehyde, and n-isovaleraldehyde.

10. The method of manufacturing according to claim 1, characterized in that: the pressure of the hydrogen in the reaction vessel is 0.5-5.0 Mpa.

11. The method according to claim 1, wherein the pressure of hydrogen in the reaction vessel is 1.0 to 4.0Mpa.

12. The method of manufacturing according to claim 1, characterized in that: the temperature of the reaction is 80-180 ℃.

13. The process according to claim 1, wherein the temperature of the reaction is 100 to 160 ℃.

14. A process for preparing a catalyst for preparing a 2-alkylcyclohexanone homolog, characterized by: the method comprises the following steps:

and (3) immersing the porous alkaline carrier or the precursor thereof in a solution containing alkaline active elements and hydrogenation active elements, drying and calcining to obtain the catalyst.