CN111318280A

CN111318280A - Aldehyde or ketone hydrogenation catalyst, preparation method and use method thereof

Info

Publication number: CN111318280A
Application number: CN201811535177.6A
Authority: CN
Inventors: 王中华; 赵聪; 袁帅; 黎源
Original assignee: Wanhua Chemical Group Co Ltd; Wanhua Chemical Ningbo Co Ltd
Current assignee: Wanhua Chemical Group Co Ltd; Wanhua Chemical Ningbo Co Ltd
Priority date: 2018-12-14
Filing date: 2018-12-14
Publication date: 2020-06-23
Anticipated expiration: 2038-12-14
Also published as: CN111318280B

Abstract

The invention relates to the field of chemical industry, and particularly provides a catalyst for hydrogenation of aldehyde or ketone, preferably C3-C5 aldehyde or ketone, more preferably 3-hydroxypropionaldehyde, a preparation method thereof, and a method for preparing alcohol, preferably 1, 3-propanediol by using the catalyst₂The catalyst comprises, by mass, Cu in the catalyst accounts for 20.0-40.0% of the total mass of the catalyst, M, namely the content of a cocatalyst active component accounts for 0.1-1.0% of the total mass of the catalyst, and the balance is a carrier. The preparation method of the catalyst is an ammonia distillation method. Using the catalystUsed in the process of preparing 1, 3-propylene glycol by hydrogenating 3-hydroxypropionaldehyde, the conversion rate of hydrogenation>99.9% selectivity>99.0 percent, the catalyst is stable and not easy to run off in the hydrogenation process, and the stability of the catalyst is not obviously reduced after a service life test of 1000 h.

Description

Aldehyde or ketone hydrogenation catalyst, preparation method and use method thereof

Technical Field

The invention relates to a hydrogenation catalyst for aldehyde or ketone, in particular to a C3-C5 aldehyde or ketone hydrogenation catalyst, in particular to a 3-hydroxypropionaldehyde hydrogenation catalyst and a preparation method thereof, and a method for preparing alcohol under the catalysis of the catalyst, in particular to a method for preparing 1, 3-propanediol from 3-hydroxypropionaldehyde; more particularly, the present invention relates to a Cu-Si system catalyst, a preparation method thereof, and a method for preparing alcohol under the catalysis of the catalyst, especially 1, 3-propanediol prepared from 3-hydroxypropionaldehyde.

Background

1, 3-propylene glycol is an important chemical raw material, and the most important purpose is to be used as a polymer material with excellent polymer monomer synthesis performance, particularly for producing PTT.

The existing production process adopts a 3-hydroxypropionaldehyde hydrogenation method to produce 1, 3-propylene glycol, wherein the production method of the raw material 3-hydroxypropionaldehyde mainly comprises an acrolein hydration method and an ethylene oxide hydroformylation method. The 3-hydroxypropanal hydrogenation process generally adopts a fixed bed process or a kettle type process, and the 3-hydroxypropanal hydrogenation catalyst mainly comprises Raney nickel (namely a supported catalyst taking nickel as an active center) and a supported catalyst taking noble metals such as ruthenium and the like as the active center.

For example, CN1342521A mentions that raney nickel is used as a hydrogenation catalyst for 3-hydroxypropanal, the conversion rate of 3-hydroxypropanal is 100%, and the selectivity of 1, 3-propanediol is > 99%, but raney nickel catalyst has the problem of weak support force of internal framework of particles, resulting in poor mechanical strength of particles, and pulverization of particles due to compression and washing, resulting in loss of catalyst and reduced catalyst activity, and after the lost catalyst Ni enters a rectification column along with a reaction solution, some side reactions may be caused after the concentration of Ni in the column bottom, and products are lost during separation, or other uncertain hazards are caused, and an adsorption process needs to be added before separation to remove Ni in the reaction solution.

US5364984And a Pt/TiO compound₂The method for preparing 1, 3-propylene glycol by catalyst hydrogenation has the selectivity of 3-hydroxypropionaldehyde hydrogenation of 95.6 percent, and the method for preparing 1, 3-propylene glycol by catalyst hydrogenation with ruthenium as an active center and silicon, titanium oxide and active carbon as carriers is mentioned in US6297408, and 5 percent Ru/SiO is adopted₂And 2% Ru/TiO₂According to this document, 5% Ru/SiO can be obtained₂And 2% Ru/TiO₂The conversion of 3-hydroxypropanal after hydrogenation was 89% and 69%, respectively.

According to the above prior art, it can be seen that, in the current method for preparing alcohol by hydrogenation of aldehyde or ketone, especially for preparing 1, 3-propanediol by hydrogenation of 3-hydroxypropanal, raney nickel and nickel-based catalysts are mainly used, but due to the characteristics of the Ni-based catalysts, the strength of the catalyst skeleton is deviated or easily dissolved and lost, the activity of the catalyst in the use process is gradually weakened, and meanwhile, the lost catalysts are easily enriched, concentrated and catalyzed by other side reactions in the separation process, thereby causing certain process hazards.

There are also methods using supported catalysts having a noble metal such as ruthenium as an active center, and these catalysts contain a noble metal, resulting in high catalytic production costs. And the catalysts are easy to lose in the using process, so that the activity of the catalysts is influenced, and the conversion rate of the 3-hydroxypropionaldehyde is low.

Therefore, there is a need to develop a new catalyst for the hydrogenation of aldehydes or ketones to alcohols, especially 3-hydroxypropanal to 1, 3-propanediol, to overcome the above-mentioned problems in the prior art.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a high-activity copper-based catalyst for catalyzing aldehyde or ketone hydrogenation to prepare alcohol, in particular C3-C5 aldehyde or ketone hydrogenation to prepare alcohol, and more particularly aims at the process of hydrogenating and converting 3-hydroxypropionaldehyde into 1, 3-propanediol.

The catalyst of the invention has higher stability and good particle mechanical strength, overcomes the problems of easy loss of Raney nickel and nickel catalysts in the using process and high production cost of noble metal catalysis, and has the problems of low catalyst activity, incomplete hydrogenation and high aldehyde group of products. The method realizes the preparation of alcohol by catalyzing aldehyde or ketone hydrogenation by a catalyst without precious metal or with a small amount of precious metal, in particular to the preparation of alcohol by C3-C5 aldehyde or ketone hydrogenation, and in particular to the preparation of 1, 3-propylene glycol by 3-hydroxypropionaldehyde hydrogenation. Compared with the existing process for preparing alcohol by aldehyde or ketone hydrogenation, the preparation process adopting the catalyst can be carried out at lower temperature, the conversion rate of aldehyde or ketone, especially 3-hydroxypropionaldehyde is higher, the selectivity of 1, 3-propanediol is higher, and the economic benefit is improved.

The invention firstly provides a catalyst for aldehyde or ketone hydrogenation, which is characterized in that the catalyst is a Cu-Si system catalyst, and the content of Cu in the catalyst is 20.0-40.0% of the total mass of the catalyst by mass.

Preferably, the catalyst has a structural formula of Cu-M-SiO₂Wherein M is a group VIII element.

In the structural formula of the catalyst, Cu is used as a main active component, M is used as a cocatalyst active component, and SiO₂Is a carrier.

In the present invention, the carrier may also be one or more of the following substances:

molecular sieves, diatomaceous earth, titanium dioxide, zirconium dioxide, activated carbon, silicon carbide, carbon black, carbon fibers, and carbon nanotubes.

Preferably, the content of M in the catalyst is 0.1-1.0% by mass of the total mass of the catalyst, and the SiO is₂The content of (A) is 59.9-79.0% of the total mass of the catalyst.

Preferably, M is selected from one or more of Ni, Ru, Rh, Pd, Os, Ir and Pt.

Preferably, the specific surface area of the catalyst is 300-600m²Per g, pore volume of 0.5-1.0cm³/g。

The invention also provides a method for preparing the Cu-Si system catalyst, which is characterized by comprising the following steps:

1) dissolving copper salt in water to prepare copper salt solution, wherein the copper salt is preferably copper sulfate, copper phosphate, copper nitrate or copper hydrochloride, and is more preferably copper nitrate;

2) adding one or more C1-C5 monohydric alcohols and one or more organosilicon compounds to the copper salt solution obtained in the step 1), wherein the C1-C5 monohydric alcohols are preferably methanol, ethanol, propanol, isopropanol, butanol, sec-butanol, isobutanol, pentanol or 3-methyl butanol, more preferably methanol, ethanol or propanol, the organosilicon compounds are preferably orthosilicate esters of C1-C5 alcohols, more preferably tetramethyl orthosilicate, tetraethyl orthosilicate, tetrapropyl orthosilicate, tetraisopropyl orthosilicate, tetrabutyl orthosilicate, tetraisobutyl orthosilicate, tetra-sec-butyl orthosilicate or tetrapentyl orthosilicate, particularly preferably tetramethyl orthosilicate, tetraethyl orthosilicate or tetrapropyl orthosilicate, the mass ratio of the water, the C1-C5 monohydric alcohols and the organosilicon compounds is water, the C1-C5 monohydric alcohols, the organosilicon compounds are 1-3 (1-5), stirring to form sol-gel liquid;

3) aging the sol-gel formed in step 2) at room temperature;

4) drying the aged sol-gel liquid obtained in the step 3) in an oven to obtain a catalyst precursor;

5) preparing an ammonia water solution with the pH value of 10-12, adding the catalyst precursor obtained in the step 4) into the prepared ammonia water solution, evaporating ammonia until the pH value is 7-8, preferably 7-7.5, stopping ammonia evaporation, cooling to room temperature, performing suction filtration, drying and roasting the solid to obtain the catalyst.

The invention also provides a Cu-M-SiO catalyst for preparation₂The method is characterized in that the method is an ammonia evaporation method, an organic silicon compound is taken as a silicon source, and the specific preparation method comprises the following steps:

1) dissolving copper salt and M salt in water to prepare a mixed salt solution, wherein the copper salt is preferably copper sulfate, copper phosphate, copper nitrate or copper hydrochloride, more preferably copper nitrate, the M salt is preferably M sulfate, M phosphate, M nitrate or M hydrochloride, and more preferably M nitrate;

2) adding one or more C1-C5 monohydric alcohols and one or more organosilicon compounds to the mixed salt solution obtained in step 1), wherein the C1-C5 monohydric alcohol is preferably methanol, ethanol, propanol, isopropanol, butanol, sec-butanol, isobutanol, pentanol or 3-methyl butanol, more preferably methanol, ethanol or propanol, the organosilicon compound is preferably an orthosilicate ester of a C1-C5 alcohol, more preferably tetramethyl orthosilicate, tetraethyl orthosilicate, tetrapropyl orthosilicate, tetraisopropyl orthosilicate, tetrabutyl orthosilicate, tetraisobutyl orthosilicate, tetra-sec-butyl orthosilicate or tetrapentyl orthosilicate, particularly preferably tetramethyl orthosilicate, tetraethyl orthosilicate or tetrapropyl orthosilicate, and the mass ratio of the water, the C1-C5 monohydric alcohol and the organosilicon compound is water: C1-C5 monohydric alcohol, namely organic silicon compound 1, (1-3) and (1-5), and stirring to form sol gel;

3) aging the sol-gel formed in step 2) at room temperature;

In the above-mentioned method for producing the catalyst, it is preferable that

The aging time in the step 3) is 20-30 h;

in the step 4), the aged sol-gel liquid is dried in an oven for 26 to 55 hours at the drying condition of 50 to 170 ℃;

in the step 5), ammonia evaporation is carried out at the temperature of 60-90 ℃, and the solid is dried and roasted at the temperature of 200-400 ℃ for 5-15 h.

Preferably, in the step 4), the process of drying the aged sol-gel in the oven is as follows:

drying at 50-100 deg.C for 5-10 h, drying at 110-130 deg.C for 20-40 h, and drying at 140-170 deg.C for 1-5 h.

Preferably, in the step 5), the process of drying and roasting the solid is as follows:

drying at 200-300 deg.C for 5-10 h, and calcining at 350-400 deg.C for 0.5-5 h.

Preferably, in the step 2), the stirring to form the sol-gel is performed for 2 to 5 hours at the temperature of between 40 and 100 ℃;

preferably, in the step 2), the monohydric alcohol of C1-C5 and the organosilicon compound are added into the mixed salt solution obtained in the step 1) under the condition of stirring.

The room temperature in the above method means 10 to 35 ℃.

In the method, in the step 5), the catalyst precursor is added into the prepared ammonia water solution, wherein the mass ratio of the catalyst precursor to the ammonia water solution is 1 (5-20).

The invention also provides a method for preparing alcohol by catalyzing aldehyde or ketone hydrogenation, preferably C3-C5 aldehyde or ketone hydrogenation, in particular 3-hydroxypropionaldehyde hydrogenation to prepare 1, 3-propanediol by using the catalyst or the catalyst prepared by the method;

preferably, the starting material of the hydrogenation reaction comprises an aldehyde or ketone aqueous solution with the mass concentration of 10-30%;

more preferably, the temperature of the hydrogenation reaction is 50-140 ℃, more preferably, the pressure of the hydrogenation reaction is 2-7 Mpa, and further preferably, the volume space velocity of the hydrogenation reaction is 0.5-5h^-1。

Preferably, the method adopts a mode of externally circulating and diluting the aqueous solution of aldehyde or ketone, preferably, the hydrogenated reaction liquid is externally circulated to the inlet of the reactor, and the aqueous solution of aldehyde or ketone and the hydrogenated reaction liquid are mixed in a mass ratio of 1:5-1:20 and then are subjected to catalytic hydrogenation.

The method for diluting the aqueous solution of aldehyde or ketone by external circulation is that after the raw materials are added into the reactor, the generation of products is detected at the outlet of the reactor, once the generation of the products is detected, hydrogenated reaction liquid containing the products is connected back to the inlet of the reactor from the outlet of the reactor, and enters the reactor together with the raw materials for continuous reaction, and the hydrogenated reaction liquid is circulated in such a way.

Preferably, the hydrogenation reaction is carried out in a fixed bed reactor.

The invention aims to solve the problems that the active components of Raney nickel catalysts and supported nickel catalysts used in the existing production process for preparing alcohol by hydrogenation of aldehyde or ketone, especially 1, 3-propylene glycol, are easy to lose, and other side reactions are easy to enrich, concentrate and catalyze in the separation process, and the stability of the catalysts is poor. And the supported catalysts which use noble metals such as ruthenium and the like as active centers are adopted, the catalysts contain noble metals, so that the catalytic production cost is high, and the catalysts are easy to run off to influence the activity of the catalysts, so that the conversion rate of the 3-hydroxypropionaldehyde is low, and the selectivity of the 1, 3-propanediol is low.

The Cu-Si system catalyst of the invention uses Cu with lower price, and is different from the Cu system catalyst added with zinc, chromium, alkali metal and the like at present, the Cu content of the Cu-Si system catalyst is optimized, and a small amount of noble metal (the mass content of the noble metal in the catalyst of the invention is at least half of that in the prior art) or no noble metal is adopted, so that compared with the process of preparing 1, 3-propylene glycol by the hydrogenation of the nickel system or the noble metal catalyst mainly used at present, the hydrogenation cost is obviously reduced, the Cu-Si system catalyst is more economic, and accords with the green chemical concept.

In the Cu-Si system catalyst of the present invention, Cu-M-SiO is preferable₂In the preferred catalyst, Cu is used as a main active ingredient and has a synergistic effect with a cocatalyst active ingredient M, so that the catalytic system disclosed by the invention has higher catalytic activity at a lower temperature, the thorough hydrogenation can be ensured, the aldehyde group content of a hydrogenated product is reduced, the reaction operation temperature is reduced, and the problem of excessive side reactions caused by poor thermal stability of 3-hydroxypropionaldehyde due to high temperature is solved. The catalyst is used in the process of preparing 1, 3-propylene glycol by hydrogenating 3-hydroxypropionaldehyde, and the conversion rate of the 3-hydroxypropionaldehyde is>99.9% selectivity to 1, 3-propanediol>99.0 percent, the catalyst is stable and not easy to run off in the hydrogenation process, and the stability of the catalyst is not obviously reduced after a service life test of 1000 h.

In the preparation process of the catalyst, the monohydric alcohol of C1-C5, especially the introduction of ethanol, is introduced into the catalyst precursor, so that the dispersion of a silicon source in a solution is increased, the dispersion of active components of the catalyst is increased, the components in the catalyst precursor are distributed more uniformly, the local aggregation of the active components is avoided, the components in the formed catalyst precursor are distributed more uniformly, the problems of non-uniform distribution of metals in the catalyst and non-uniform distribution of the activity in the production process are avoided, and the stability of the catalyst is improved.

In the preparation process of the catalyst, the catalyst precursor is subjected to ammonia evaporation and drying and roasting treatment at a higher temperature after ammonia evaporation, so that the components in the catalyst precursor are more uniformly distributed, the acidity and the alkalinity of the catalyst are kept in an optimum state, and the selectivity of the product 1-3-propylene glycol is improved. In addition, the ammonia evaporation and the drying and roasting treatment at higher temperature after the ammonia evaporation are favorable for forming the catalyst with a stable layered polyhedral crystal structure, the catalyst is not easy to pulverize, has better mechanical strength and larger specific surface area of the active component, has better stability, and can overcome the problems of poor stability and easy loss of the active component in the hydrogenation process of the existing catalyst.

The invention also provides a method for preparing alcohol by catalyzing aldehyde or ketone hydrogenation by using the catalyst, in particular to a method for preparing 1, 3-propylene glycol by catalyzing 3-hydroxypropionaldehyde, wherein a 3-hydroxypropionaldehyde aqueous solution is diluted by external circulation, and the hydrogenated reaction liquid is subjected to circulation dilution, so that the space velocity of the reaction volume can be improved by 10 times, the raw material amount for treatment is obviously improved, the production efficiency is improved, and the selectivity of the 1, 3-propylene glycol is increased under the condition of ensuring the conversion rate of the 3-hydroxypropionaldehyde which is similar to the process without adopting the external circulation dilution.

Drawings

FIG. 1 is a schematic process flow diagram of a hydrogenation process without using external recycle dilution in the example of the present invention, in which 1 ' represents hydrogen, 2 ' represents an aqueous solution of 3-hydroxypropanal, and 3 ' represents a hydrogenated reaction solution at the outlet of a reactor.

FIG. 2 is a schematic process flow diagram of a hydrogenation process using external recycle dilution in an embodiment of the present invention, in which 1 represents hydrogen, 2 represents an aqueous solution of 3-hydroxypropanal, 3 represents a hydrogenated reaction solution at the outlet of a reactor, and 4 represents a hydrogenated reaction solution externally recycled to the inlet of the reactor.

Detailed Description

The following examples are intended to illustrate the practice and advantages of the present invention in more detail and are not intended to limit the scope of the practice of the invention.

In the characterization of the catalysts in the following examples, the composition of the catalysts was determined by an ICP spectrometer, model TY-9920, Chongqing Hakka, and the specific surface area and pore volume were determined by an F-sorb2400 testing specific surface area instrument.

The gas phase analysis conditions in the following examples are as follows:

shimadzu gas chromatograph, RTX-WAX column, standing at 60 deg.C for 5min, heating to 80 deg.C at 10 deg.C/min, standing for 5min, heating to 100 deg.C at 10 deg.C/min, standing for 5min, heating to 160 deg.C at 10 deg.C/min, and standing for 15min, and using correction normalization method.

The sources of materials and reagents in the following examples are shown in table 1 below:

TABLE 1

Instrument and reagent	Origin of origin	Specification of
			ICP spectrometer	Chongqing Hake	TY-9920 type
Gas chromatograph	Shimadzu
			Specific surface area meter	Golden spectrum technology	F-sorb2400
Ethanol	Is commercially available	>99％
			Tetraethyl orthosilicate	Is commercially available	>99％

The inorganic salts used in the following examples are all commercially available unless otherwise specified.

The following examples 1-6 document the preparation of catalysts 1-6.

Example 1

Dissolving 17.6g of copper nitrate and 0.28g of rhodium nitrate in 43g of distilled water to obtain a mixed salt solution, adding 80g of ethanol and 48.2g of tetraethyl orthosilicate while stirring the mixed salt solution, stirring the mixture at 70 ℃ for 4 hours to form a sol gel, aging the gel at room temperature for 24 hours, drying the gel in an oven, drying the gel at 70 ℃ for 8 hours, then drying the gel at 110 ℃ for 40 hours, finally drying the gel at 160 ℃ for 2 hours to obtain a catalyst precursor, adding the obtained catalyst precursor to 170mL of an aqueous ammonia solution with the pH of 11, evaporating ammonia at 80 ℃ until the pH is 7, cooling the solution to room temperature, performing suction filtration, drying the obtained solid at 210 ℃ for 10 hours, and calcining the obtained solid at 390 ℃ for 1 hour to obtain the catalyst 1. ICP analysis is carried out to determine that the following components in the catalyst 1 account for the total mass of the catalyst 1 in percentage by mass: cu 30%, Rh0.5%, the balance being SiO₂The BET analysis showed that the specific surface area of catalyst 1 was 542 (m)²Per g), pore volume of 0.95 (cm)³/g)。

Example 2

In this example, the catalyst was prepared by the same procedure as in example 1 except that 0.28g of rhodium nitrate used in example 1 was changed to 0.22g of palladium nitrate, and the other preparation procedures were the same as in example 1 to obtain catalyst 2. ICP analysis determines that the catalyst 2 comprises the following components in percentage by mass of the total mass of the catalyst 2: cu30 percent, Pd0.5 percent and the balance of SiO₂The specific surface area of the catalyst 2 was 517 (m) by BET analysis²Per g), pore volume of 0.83 (cm)³/g)。

Example 3

13.5g of copper nitrate and 0.45g of rhodium nitrate were dissolved in 43g of distilled water to obtain a mixed salt solution, 90g of ethanol and 52.8g of tetraethyl orthosilicate are added while the mixed salt solution is stirred, stirring at 50 deg.C for 5h to form sol gel, aging at room temperature for 27h, drying in an oven, drying at 90 deg.C for 5 hr, drying at 120 deg.C for 30 hr, drying at 140 deg.C for 5 hr to obtain catalyst precursor, adding the catalyst precursor into 200mL ammonia water solution with pH of 11, performing ammonia distillation at 90 ℃ until the pH value is 7, stopping ammonia distillation, cooling to room temperature, performing suction filtration, drying the obtained solid at 260 ℃ for 6 hours, and roasting at 360 ℃ for 3 hours to obtain a catalyst 3, wherein ICP analysis determines that the catalyst 3 comprises the following components in percentage by mass based on the total mass of the catalyst 3: cu 23%, Rh0.8%, the balance being SiO₂Catalyst 3 had a specific surface area of 487 (m) by BET analysis²Per g), pore volume of 0.81 (cm)³/g)。

Example 4

In this example, the catalyst was prepared in the same manner as in example 3 except that 0.45g of rhodium nitrate used in example 3 was changed to 0.35g of palladium nitrate, and the other preparation process was the same as in example 3 to obtain catalyst 4. ICP analysis determines that the catalyst 4 comprises the following components in percentage by mass of the total mass of the catalyst 4: cu 23%, Pd0.8%, and SiO in balance₂The BET analysis of the specific surface area of the catalyst 2 was 467 (m)²Per g), pore volume of 0.71 (cm)³/g)。

Example 5

Dissolving 22.3g of copper nitrate and 0.11g of rhodium nitrate in 43g of distilled water to obtain a mixed salt solution, adding 80g of ethanol and 42.8g of tetraethyl orthosilicate while stirring the mixed salt solution, stirring the mixture at 100 ℃ for 2 hours to form sol gel, aging the sol gel at room temperature for 24 hours, drying the gel in an oven, drying the gel at 80 ℃ for 7 hours in sequence, and then drying the dried gel at 130 ℃ for 23 hoursAnd finally drying at 150 ℃ for 3h to obtain a catalyst precursor, adding the obtained catalyst precursor into 150mL of ammonia water solution with the pH value of 11, evaporating ammonia at 70 ℃ until the pH value is 7, stopping ammonia evaporation, cooling to room temperature, performing suction filtration, drying the obtained solid at 240 ℃ for 8h, and calcining at 370 ℃ for 2h to obtain a catalyst 5, wherein the percentage of the following components in the catalyst 5 in terms of the total mass of the catalyst is determined by ICP analysis, and the percentage of the total mass of the catalyst is as follows: cu 38%, Rh0.2%, the balance being SiO₂The BET analysis showed that the specific surface area of the catalyst 5 was 436 (m)²Per g), pore volume of 0.69 (cm)³/g)。

Example 6

In this example, the catalyst was prepared by the same procedure as in example 5 except that 0.11g of rhodium nitrate used in example 5 was changed to 0.87g of palladium nitrate, and the other preparation procedures were the same as in example 5 to obtain catalyst 6. ICP analysis determines that the catalyst 6 comprises the following components in percentage by mass of the total mass of the catalyst 6: cu 38%, Pd0.2%, and SiO as the rest₂The specific surface area of the catalyst 6 was 427 (m) by BET analysis²Per g), pore volume of 0.65 (cm)³/g)。

Example 7

The catalyst 1-6 is used for catalyzing the hydrogenation of 3-hydroxypropanal to prepare 1, 3-propanediol:

the catalysts 1-6 are respectively filled in six fixed beds, and the volume space velocity is 0.5h under the conditions of the concentration of the 3-hydroxypropionaldehyde aqueous solution, the temperature and the pressure of the hydrogenation reaction shown in the table 2^-1The process flow diagram of the hydrogenation process of the embodiment is shown in fig. 1, and the specific flow is as follows: adding the 3-hydroxypropionaldehyde aqueous solution into different fixed beds respectively filled with catalysts 1-6, hydrogenating at the temperature and the pressure and at the volume space velocity, reacting, and obtaining the 1, 3-propylene glycol at the outlet of the reactor. The hydrogenation results under different conditions are also shown in table 2.

TABLE 2

Example 8

17.6g of copper nitrate was dissolved in 43g of distilled water, 80g of ethanol and 48.2g of tetraethyl orthosilicate were added with stirring, and then the procedure of example 1 was followed, stirring at 70 deg.C for 4 hr to form sol gel, aging at room temperature for 24 hr, drying in an oven, drying at 70 deg.C for 8 hr, drying at 110 deg.C for 40 hr, drying at 160 deg.C for 2 hr to obtain catalyst precursor, adding the catalyst precursor into 170mL of ammonia water solution with pH of 11, and (2) evaporating ammonia at 80 ℃ until the pH value is 7, stopping ammonia evaporation, cooling to room temperature, performing suction filtration, drying the obtained solid at 210 ℃ for 10h, and roasting at 390 ℃ for 1h to obtain the supported Cu-Si catalyst taking silicon dioxide as a carrier, wherein the Cu content in the catalyst is 32.7%, and the rest is SiO.₂The technological process shown in FIG. 1 is adopted, namely, a 20% aqueous solution of 3-hydroxypropanal is added into a fixed bed filled with the supported Cu-Si catalyst with 32.7% copper content, and the mixture is subjected to reaction at 140 ℃ and under 5MPa for 0.5h^-1Hydrogenation is carried out at a volume space velocity, and 1, 3-propylene glycol is obtained at the outlet of the reactor. In this example, the conversion of 3-hydroxypropanal was 86.3% and the selectivity to 1, 3-propanediol was 89.5%.

As can be seen from the results of examples 1 to 8 above, in the case of preparing 1, 3-propanediol by catalyzing 3-hydroxypropionaldehyde with a Cu-Si system catalyst, Cu-M-SiO, which is a simplified structure, is used₂Compared with a Cu-Si catalyst (namely a Cu-Si system catalyst without M), the catalyst can further reduce the reaction temperature, so that the 3-hydroxypropionaldehyde reacts in a more stable state, side reactions are further reduced, and the conversion rate of the 3-hydroxypropionaldehyde and the selectivity of the 1, 3-propanediol are improved.

Example 9

A long-period experiment is carried out by using the catalyst 5, and the process flow shown in figure 1 is adopted, namely, 3-hydroxypropionaldehyde aqueous solution with the concentration of 20 percent is added into a fixed bed filled with the catalyst 5, and the mixture is subjected to reaction at the temperature of 110 ℃ and the pressure of 5Mpa for 0.5h^-1Hydrogenation is carried out at a volume space velocity, reaction is carried out, the continuous operation is carried out for 1000h, and 1, 3-propylene glycol is obtained at the outlet of the reactor. The results measured at different run times are shown in table 3 below.

TABLE 3

Example 10

The catalyst 5 is used for catalyzing the hydrogenation of 3-hydroxypropanal to prepare the 1, 3-propanediol, in the embodiment, the preparation process adopts a mode of diluting the 3-hydroxypropanal aqueous solution in an external circulation mode, the product generation is detected by a gas phase analyzer at the outlet of the reactor, the obtained hydrogenated reaction liquid is externally circulated back to the inlet of the reactor after the product generation is detected, the concentration of the 3-hydroxypropanal aqueous solution is 20 percent, the proportion of the hydrogenated reaction liquid and the raw material 3-hydroxypropanal is shown in the following table 4, the temperature of the hydrogenation reaction is 130 ℃, the pressure is 5Mpa, and the volume space velocity is 5h^-1The process flow diagram of the hydrogenation process adopted in this example is shown in fig. 2, and the specific process flow is as follows: adding 20% 3-hydroxypropanal aqueous solution into a fixed bed filled with catalyst 5, and heating at 130 deg.C under 5Mpa for 5 hr^-1Hydrogenation is carried out under a volume space velocity, the generation of 1, 3-propylene glycol is detected at the outlet of the reactor, once the generation of the 1, 3-propylene glycol is detected, the hydrogenated reaction liquid containing the 1, 3-propylene glycol is connected back to the inlet of the reactor from the outlet of the reactor according to the proportion shown in the table 4, and enters the reactor together with hydrogen and 3-hydroxypropanal aqueous solution for continuous reaction, and the hydrogenated reaction liquid is circulated in this way. The results at different ratios of the hydrogenated reaction liquid to the feed 3-hydroxypropanal are shown in Table 4 below.

TABLE 4

According to the results of example 10, it can be seen that the adoption of the external circulation dilution method of the 3-hydroxypropanal aqueous solution can increase the reaction volume airspeed by 10 times, significantly increase the amount of raw materials to be treated, increase the production efficiency, and increase the selectivity of 1, 3-propanediol while ensuring the conversion rate of 3-hydroxypropanal similar to the process without the external circulation dilution.

Comparative example 1

Raney nickel (Grace Ni228, provided by Grace corporation) is used as a catalyst, the process flow shown in figure 1 is adopted, namely, 3-hydroxypropionaldehyde aqueous solution with the concentration of 20 percent is added into a fixed bed filled with Raney nickel, and the mixture is heated at the temperature of 110 ℃ and under the pressure of 5MPa for 0.5h^-1Hydrogenation is carried out at a volume space velocity, the reaction is continuously operated for 60h, and the results measured at different operation times are shown in the following table 5.

TABLE 5

Comparative example 2

A supported nickel catalyst with alumina as carrier is used as catalyst (Zhuangxin Ni 500, provided by Zhuangxin Wanfeng), wherein the content of nickel is 20%, and the rest is alumina, the process shown in figure 1 is adopted, namely, a 3-hydroxypropionaldehyde aqueous solution with the concentration of 20% is added into a fixed bed filled with the supported nickel catalyst with alumina as carrier, and the mixture is subjected to reaction at the temperature of 110 ℃ and the pressure of 5Mpa for 0.5h^-1Hydrogenation is carried out at a volume space velocity, the reaction is continuously operated for 60h, and the results measured at different operation times are shown in the following table 6.

TABLE 6

It can be seen from comparative examples 1 and 2 that, compared with the existing raney nickel or supported nickel catalyst, the loss of the active component of the catalyst is significantly reduced after the running time of 60 hours or even 1000 hours, so that the catalyst is not easy to be pulverized and lost, the internal supporting force is good, and the mechanical property is significantly improved.

Claims

1. The catalyst for hydrogenation of aldehyde or ketone is characterized by being a Cu-Si system catalyst, wherein the content of Cu in the catalyst is 20.0-40.0% of the total mass of the catalyst by mass.

2. The catalyst of claim 1, wherein the catalyst has the structural formula Cu-M-SiO₂Wherein M is a group VIII element.

3. The catalyst according to claim 2, wherein the content of M in the catalyst is 0.1% to 1.0% by mass of the total mass of the catalyst, and the SiO is₂The content of (A) is 59.9-79.0% of the total mass of the catalyst.

4. A catalyst according to claim 2 or 3, wherein M is selected from one or more of Ni, Ru, Rh, Pd, Os, Ir and Pt.

5. The catalyst as claimed in any one of claims 1 to 4, wherein the specific surface area of the catalyst is 300-600m²Per g, pore volume of 0.5-1.0cm³/g。

6. A method of preparing the catalyst of claim 1, comprising the steps of:

3) aging the sol-gel formed in step 2) at room temperature;

7. A process for the preparation of a catalyst according to any one of the preceding claims 2 to 5, characterized in that it is an ammonia distillation process, using an organosilicon compound as silicon source, comprising the following steps:

3) aging the sol-gel formed in step 2) at room temperature;

8. The method according to claim 6 or 7,

the aging time in the step 3) is 20-30 h;

9. The method according to claim 8, wherein in the step 4), the aged sol-gel solution is dried in an oven as follows:

10. The method as claimed in claim 8, wherein in the step 5), the drying and roasting processes of the solid are as follows:

drying at 200-300 deg.C for 5-10 h, and calcining at 350-400 deg.C for 0.5-5 h.

11. The method according to claim 6 or 7, wherein in the step 2), the stirring to form the sol-gel is performed for 2 to 5 hours at 40 to 100 ℃;

12. A process for catalyzing an aldehyde or ketone hydrogenation reaction to produce an alcohol using a catalyst as claimed in any one of claims 1 to 5 or a catalyst produced by a process as claimed in any one of claims 6 to 11;

13. The method for preparing alcohol according to claim 12, wherein the method employs an external circulation dilution method for aldehyde or ketone aqueous solution, preferably the hydrogenated reaction solution is externally circulated to the inlet of the reactor, and the aldehyde or ketone aqueous solution and the hydrogenated reaction solution are mixed in a mass ratio of 1:5-1:20 and then are subjected to catalytic hydrogenation.