CN107999089B

CN107999089B - Catalyst for producing diethyltoluenediamine and preparation method and application thereof

Info

Publication number: CN107999089B
Application number: CN201711219000.0A
Authority: CN
Inventors: 任树杰; 张聪颖; 刘振国; 李鑫; 唐磊; 吴健; 姜庆梅; 黎源
Original assignee: Wanhua Chemical Group Co Ltd
Current assignee: Wanhua Chemical Group Co Ltd
Priority date: 2017-11-28
Filing date: 2017-11-28
Publication date: 2021-02-02
Anticipated expiration: 2037-11-28
Also published as: CN107999089A

Abstract

The invention discloses a supported catalyst for producing diethyltoluenediamine, which comprises a modified carrier and a supported active component; wherein the modified carrier is prepared by introducing a soluble silicon-containing compound and a boron-containing compound into a carrier, drying and roasting the carrier to obtain the modified carrier containing SiO obtained by decomposing the soluble silicon-containing compound and the boron-containing compound₂And B₂O₃The modified support of (1); the invention also discloses a preparation method and application of the catalyst. The catalyst of the present invention is suitable for the alkylation reaction of aromatic amine, and has high activity and selectivity for continuously producing diethyl toluene diamine by alkylation of toluene diamine. The catalyst has the advantages of simple preparation process, good economy and good application prospect.

Description

Catalyst for producing diethyltoluenediamine and preparation method and application thereof

Technical Field

The invention relates to the field of preparation of diethyltoluenediamine, and particularly relates to a supported catalyst for producing diethyltoluenediamine, and a preparation method and application thereof.

Background

Diethyltoluenediamine (DETDA) is a low-viscosity, non-toxic, odorless, light yellow liquid which is a mixture of two isomers of 3, 5-diethyl-2, 4-toluenediamine (about 80%) and 3, 5-diethyl-2, 6-toluenediamine (about 20%), and has the following structural formula:

DETDA is a steric type aromatic diamine, and the steric effect of ethyl and methyl makes the activity of DETDDA much lower than that of Toluene Diamine (TDA), and the reaction speed of DETDDA and polyurethane prepolymer is about 30 times faster than that of DMTDA and MOCA. DETDA is a chain extender of polyurethane and polyurea elastomers, can be used as a polyurethane and epoxy resin curing agent, and has the advantages of high reaction speed, high product strength, hydrolysis resistance, heat resistance and the like; in addition, the product can also be used for paint, lubricant, industrial grease antioxidant, chemical synthesis intermediate and the like.

The DETDA usually takes toluenediamine and ethylene as raw materials, and is subjected to alkylation reaction under the conditions of high temperature and high pressure in the presence of a catalyst to obtain a crude product of DETDA, and the crude product of DETDA is further separated and removed from the catalyst and is rectified to obtain a pure product of DETDA.

The reaction process is as follows:

main reaction:

side reaction of deamination:

demethylation side reaction:

n-alkylation side reaction:

from the above chemical reaction process, the alkylation reaction of toluenediamine has several problems:

1) the reaction is complex, the byproducts are many, and the product selectivity is poor;

2) the post-treatment needs to be carried out by the steps of alkali neutralization, filtration, extraction, rectification and the like, and the problems of complicated post-treatment process, large amount of three wastes, difficult solid waste treatment, environmental pollution and the like exist;

3) the product can be qualified only by rectification, but the problems of difficult product separation and the like exist because the boiling points of the by-product and the main product are very close.

Patents US4760185, US5103059, US5124483 and US5072047 disclose processes for the synthesis of DETDA by alkylation of toluenediamine with ethylene. These processes use aluminum, zinc, aluminum/zinc alloys (aluminum/copper alloys, aluminum/magnesium alloys, etc.), Friedel-Crafts catalysts (AlCl)₃、SnCl₄、FeCl₃、BCl₃Etc.) as catalyst, firstly mixing catalyst powder with aromatic amine and stirring for several hours at a certain temperature to form a catalyst system of 'aromatic amine-aluminum', and then introducing high-pressure ethylene and TDA to carry out alkylation reaction to synthesize DETDA. The reaction temperature is generally 250-350 ℃, the reaction pressure is generally 10-20 MPa, and the reaction time is several hours. Ethylene belongs to flammable and explosive hazardous gas, alkylation reaction is carried out at high temperature and high pressure, and great potential safety hazard exists.

The Chinese invention patent (application number: 96102856.4) discloses a method for synthesizing DETDA by alkylating TDA and ethylene, which adopts aluminum powder as a catalyst, catalyzes the TDA and the ethylene to synthesize DETDA by alkylating the TDA and the ethylene after activating aromatic amine, has the preferable reaction temperature of 180-270 ℃ and the reaction pressure of 2-6 MPa, and obtains DETDA after reacting for several hours under the condition. The catalyst has low activity, high temperature and pressure required by reaction, potential safety hazard and long time required for reaction completion.

The Chinese invention patent (application number: 200410042698.X) discloses a method for synthesizing DETDA by catalyzing TDA and ethylene alkylation by using aluminum trichloride, wherein the reaction conditions are harsh, the reaction temperature is 200-400 ℃, and the reaction pressure is up to 15-50 MPa. The reaction needs to be carried out under the conditions of high temperature and high pressure, potential safety hazards exist, and in addition, AlCl₃Coking is easy to occur in the reaction process, HCl is released by decomposition, and the corrosion to equipment is serious.

The literature (synthesis and use of diethyltoluenediamine, dawn chemical, 1995, (1):32-35) reports that aluminum alkyls can be used for catalyzing the synthesis of DETDDA by the alkylation of TDA and ethylene. Particularly, when triethyl aluminum is used as a catalyst, the TDA conversion rate and the DETDA selectivity are high, but the reaction conditions are harsh, the reaction temperature is up to 300 ℃, the reaction pressure is 10.0MPa, and the reaction time is 7 hours. The reaction needs to be carried out under the conditions of high temperature and high pressure, potential safety hazards exist, and the aluminum alkylate has strong toxicity.

The Chinese invention patent (application number: 200710156324.4) discloses a method for synthesizing DETDA. The method uses aluminum, zinc, aluminum trichloride and alkylated aluminum as catalysts, firstly the catalysts and TDA are stirred for 1-1.5 hours at 105-200 ℃ to form an arylamine-aluminum catalyst system, and then high-pressure ethylene is introduced for alkylation reaction to synthesize DETDA. Compared with the single use of an aluminum alkyl catalyst or an aluminum trichloride catalyst, the catalyst system of the 'arylamine-aluminum' has higher activity, can reduce the reaction pressure and shorten the reaction time. But the reaction temperature is still as high as 290-330 ℃ and the reaction pressure is 6-8 MPa.

In summary, the catalysts used in the prior art include aluminum trichloride, alkylated aluminum, a mixed system of aluminum, zinc, aluminum alloy, aluminum trichloride, or a mixed system of aluminum, zinc, aluminum trichloride and alkylated aluminum. The catalysts are required to catalyze alkylation reaction at high temperature and high pressure, so that potential safety hazards exist; when aluminum trichloride is used as a catalyst independently, the material is easy to coke at high temperature and high pressure, and HCl is released by decomposition, so that the corrosion to equipment is serious; when the aluminum alkyl is used alone as the catalyst, the catalyst is expensive and has a great toxicity, and the like. Meanwhile, the adoption of the catalytic system has the problems of complicated post-treatment process (including the steps of alkali neutralization, filtration, extraction, rectification and the like), large amount of three wastes, difficult treatment of solid wastes, environmental pollution and the like.

It is known in the art to produce cycloalkylated aromatic amine compounds by catalytic reaction of an aromatic amine with an olefin in the presence of a zeolite catalyst. Liquid phase zeolite-based alkylation technology has replaced outdated, inefficient aluminum chloride-based technologies due to its high product purity, low capital and operating costs.

For example, U.S. Pat. No. 4,4740620 discloses the selective ring alkylation of aromatic amines to ortho alkylated products using acidic crystalline molecular sieves. The disadvantage of this invention is that the reaction conditions are severe, especially for the alkylation of ethylene, higher temperatures and pressures (temperatures up to 375 ℃ C., pressures up to 3000psig) are required. Meanwhile, the conversion rate of raw materials is low, alkylation products are mainly mono-substituted ortho-position naphthenic alkylation products, and a large amount of N-alkylation byproducts are generated in the reaction process.

Disclosure of Invention

It is an object of the present invention to provide a supported catalyst for the production of diethyltoluenediamine, which is used for the alkylation of toluenediamine to produce diethyltoluenediamine, and has high activity and selectivity.

The invention also aims to provide a preparation method of the supported catalyst, and the supported catalyst has the advantages of simple preparation process, good economy and good application prospect.

The invention also aims to provide application of the supported catalyst in the preparation of diethyltoluenediamine by alkylation of toluenediamine and ethylene.

In order to achieve one aspect of the above object, the invention adopts the following technical scheme:

a supported catalyst for the production of diethyltoluenediamine, said catalyst comprising a modified support and a supported active component; wherein the modified carrier is prepared by introducing a soluble silicon-containing compound and a boron-containing compound into a carrier, drying and roasting the carrier to obtain the modified carrier containing SiO obtained by decomposing the soluble silicon-containing compound and the boron-containing compound₂And B₂O₃The modified support of (1).

In the present invention, the solubility preferably means water-solubility. The soluble silicon-containing compound may be sodium silicate or ammonium fluorosilicate, preferably ammonium fluorosilicate. The soluble boron-containing compound can be one or more of boric acid, ammonium pentaborate and ammonium tetraborate, and boric acid is preferred.

In the present invention, the soluble silicon-containing compound and the soluble boron-containing compound may be introduced onto the support separately or simultaneously, for example, the soluble silicon-containing compound may be introduced onto the support before the soluble boron-containing compound is introduced onto the catalyst support; or the soluble silicon-containing compound and the soluble shedder-containing compound are introduced simultaneously onto the catalyst support. Those skilled in the art will understand that the introduction method can be various, for example, spraying method or dipping method can be used, and dipping method is preferred, which is simple and convenient.

It is understood by those skilled in the art that the concentration of the solution, the impregnation time or the spraying amount can be adjusted to adjust the amount of the target substance adsorbed on the carrier and thereby control the content thereof, and the introduction process can be performed once or repeatedly. In one embodiment, the excess solvent may also be removed by controlling the volume ratio of the metal salt solution to the support within a suitable range or by evaporating the resulting solid-liquid mixture of support and solution. Wherein, the impregnation method can be equal-volume impregnation or excess impregnation; the impregnation may be carried out a plurality of times or may be carried out once. For efficiency, it is preferred to use one impregnation of equal volume so that the solution is substantially completely absorbed by the support.

In step 1) of the preparation method of the catalyst of the present invention, the content of silicon introduced into the carrier of the soluble silicon-containing compound is 0.5% to 10%, preferably 3.0% to 8.0%, and more preferably 4.0% to 6.0% of the weight of the catalyst carrier, calculated as silica. The boron content of the soluble boron-containing compound introduced into the carrier is 0.05-5% of the weight of the catalyst carrier, preferably 0.1-3.0%, and more preferably 0.5-1.0% of boron trioxide.

According to the supported catalyst of the invention, the introduced soluble silicon-containing compound is decomposed into SiO after being calcined₂The soluble boron-containing compound will decompose to B₂O₃(ii) a Preferably, SiO obtained by decomposition₂0.5 to 10 percent of the modified carrier, preferably 3.0 to 8.0 percent, and more preferably 4.0 to 6.0 percent; b obtained by decomposition₂O₃0.05 to 5 percent of the modified carrier weight, preferably 0.1 percentAbout 3.0%, and more preferably about 0.5% to about 1.0%.

According to the supported catalyst of the present invention, the active component may be an active component commonly used in the art for catalyzing alkylation of toluene diamine to produce diethyl toluene diamine, preferably, the active component is selected from one or more of Pt, Pd, Ru, Rh and Ir, preferably from one or more of Pt, Pd and Ru, more preferably, the active component contains at least Ru, for example, the mass content of Ru in the active component may be not less than 20%, 40%, 60% or 80%. The content of the active component is preferably 0.05 to 5 wt%, more preferably 0.5 to 3.0 wt%, still more preferably 1.0 to 2.5 wt%, such as 2 wt%, based on the total weight of the catalyst.

In a preferred embodiment of the invention, the catalyst consists of a support, an active component and optionally auxiliaries. In the present invention, the term "optionally" means either the presence or absence thereof.

The auxiliary agent is selected from one or more of Ni, Cu, Fe, Zn, Cr, Co, Ti, V, Mo, Mn and Bi, preferably from one or more of Ni, Cu, Fe, Zn and Mo, and more preferably from Ni and/or Cu; the content of the promoter is 0 to 15 wt%, preferably 2.0 to 10.0 wt%, more preferably 4.0 to 8.0 wt%, such as 6 wt%, based on the total weight of the catalyst, to further improve the catalytic effect. In the present invention, when the content of a certain component is 0%, it means that the component is not contained.

In the present invention, the carrier may be a porous oxide carrier for catalysts commonly used in the art, and the porous metal oxide is Al₂O₃、ZrO₂、TiO₂、SiO₂And SiO₂-Al₂O₃One or more of the composites, preferably SiO₂-Al₂O₃The composite, in which the Si/Al atomic ratio may be 20-100, such as 40, 50, 80. Methods for preparing the above porous oxides are well known in the art, e.g., for Al₂O₃Mixing Al₂(SO₄)₃Preparing 6 wt% aqueous solution, adding 20 wt% NH₃·H₂O reacts for 1h under vigorous stirring to give Al (OH)₃Precipitating, filtering, washing with water, drying to obtain aluminum hydroxide product, extruding into strips, calcining at 550 deg.C for 4 hr to obtain Al₂O₃. The specific surface area of the carrier may be generally 200-600m²G, e.g. 300, 400 or 500m²The pore size may typically be 50-100nm, such as 80nm per gram.

The shape of the carrier of the present invention can be any shape, and the specific shape of the carrier can be selected according to the design of the reactor (for example, the carrier can be a kettle type, a fixed bed, a fluidized bed, a tube type or a bubbling tower type according to the actual requirement), including but not limited to one or more of a sheet shape, a strip shape, a clover shape, etc.

The catalyst of the invention is suitable for alkylation reaction of aromatic amine, and especially has extremely high activity and selectivity for preparing diethyltoluenediamine by alkylation of toluenediamine.

In order to achieve another aspect of the above object, the present invention provides a method for preparing the above catalyst, comprising:

1) after a soluble silicon-containing compound and a boron-containing compound are introduced into a carrier, the carrier is dried and roasted to prepare the modified carrier.

2) Preparing soluble salt solution corresponding to the active component and the optional auxiliary agent, and carrying out impregnation treatment on the modified carrier by using the soluble salt solution to obtain a wet modified carrier;

3) and drying, roasting and reducing the obtained wet modified carrier to obtain the supported catalyst.

Drying and calcination are common process steps in the preparation of catalysts in the art and are well known in the art. In the present invention, the drying conditions may be: at 50-150 deg.C, preferably 100-120 deg.C; the drying time is 1h to 12h, preferably 5h to 10h, such as 3h and 8 h.

In step 1), the calcination temperature may be from 100 ℃ to 700 ℃, preferably from 200 ℃ to 600 ℃, such as 300, 400 or 500 ℃; the calcination time is from 1h to 10h, preferably from 2h to 8h, for example 3,5 or 7 h. In step 3), the calcination temperature may be 200 ℃ to 600 ℃, preferably 300 ℃ to 500 ℃, such as 350, 400 or 450 ℃; the calcination time is 2h to 12h, preferably 4h to 10h, such as 6, 7 or 9 h.

In step 2), the metal salt in the salt solution includes, but is not limited to, one or more of halide, nitrate, organic acid salt and the like of the metal, preferably one or more of nitrate, formate, acetate, oxalate and the like of the metal, and more preferably nitrate of the metal. The dosage ratio of each metal element in the metal salt can be determined according to the proportion of each active component and the auxiliary component in the catalyst. As mentioned above, the impregnation process is well known in the art and will not be described in detail here.

In order to make the active component in the calcined catalyst in an oxidized state and to make the catalyst active, those skilled in the art understand that the catalyst also needs to be subjected to a reduction activation treatment, for example, reduction activation under a pure hydrogen atmosphere, wherein the reduction temperature is 100 ℃ to 400 ℃, preferably 200 ℃ to 300 ℃, such as 250 ℃; the reduction time is from 1h to 24h, preferably from 4h to 16h, such as 6, 8h, 10 or 12 h.

In order to achieve another aspect of the above objects, the present invention provides the use of the above catalyst for the alkylation of toluenediamine with ethylene to produce diethyltoluenediamine;

the process for producing diethyltoluenediamine according to the present invention may be carried out either batchwise or continuously, preferably continuously. The continuous preparation of diethyltoluenediamine is carried out in the form of a liquid-phase reaction in a tubular reactor or in the form of a gas-phase reaction.

According to the use of the present invention, preferably, the molar ratio of ethylene to toluenediamine is (1-50): 1, further preferably (5-35):1, more preferably (10-25):1, such as 15: 1 or 20: 1; preferably, the reaction temperature is 100-300 ℃, preferably 150-250 ℃, such as 180, 200 or 220 ℃; the reaction pressure is from 10bar to 70bar, preferably from 30bar to 50bar, for example 35, 40 or 45 bar.

According to the use of the present invention, preferably, the reaction is carried out in a fixed bed reactor, the catalyst space velocity being between 0.01 and 15 litres of toluenediamine per litre of catalyst per hour, preferably between 0.5 and 10 litres of toluenediamine per litre of catalyst per hour, more preferably between 2.0 and 7.0, such as 4 or 5 litres of toluenediamine per litre of catalyst per hour.

The pressure referred to in the present invention is a relative pressure.

The invention has the beneficial effects that:

the catalyst is used for preparing diethyl toluene diamine by toluene diamine and ethylene alkylation reaction, under mild reaction conditions, the conversion rate of raw materials reaches 100%, the generation of deamination, demethylation and N-alkylation side reactions is greatly inhibited, the product selectivity reaches more than 99.0%, the product yield is more than 99.0%, and the content of by-products is lower than 1.0 wt%;

according to the carrier prepared by the invention, the carrier is modified by adopting a specific soluble silicon-containing compound and a boron-containing compound, and through proper heat treatment, the loaded Si and B can well coordinate to form uniformly distributed silicon boron hydroxyl groups at specific positions on the surface of the carrier, so that more acidic proper acid centers are formed on the surface of the carrier and are matched with the original acid phase in the carrier, the acidity and the acid distribution of the carrier are more reasonable, the content of strong acid is reduced, and the expected reaction is facilitated to be carried out;

the catalyst is added with an active component Ru which is coordinated and matched with the acid center of the carrier, so that the catalytic activity of the catalyst is greatly improved, and the selectivity of the product is greatly improved by the synergistic effect of the active component and the auxiliary agent element through the addition of one or more of the auxiliary agent elements such as Ni, Cu, Fe, Zn, Cr, Co, Ti, V, Mo, Mn and Bi.

Compared with the batch process, the fixed bed process is adopted, so that the continuous large-scale production of the diethyltoluenediamine is realized, and the production efficiency is improved.

By adopting the fixed bed process, qualified products can be obtained without complicated post-treatment, the problems of three wastes and environmental pollution are thoroughly solved, the energy consumption is reduced, and the production cost is saved.

Detailed Description

The present invention will be further described with reference to the following examples, but the present invention is not limited to the examples listed, and it should also include equivalent modifications and variations to the technical solutions defined in the claims appended to the present application.

Gas chromatograph: shimadzu GC-2014(FID) Detector, DB-5 capillary column

The sample inlet is 300 ℃, and the detector is 320 ℃; temperature rising procedure: the product was measured by raising the temperature from 80 ℃ to 230 ℃ at 10 ℃/min and then to 300 ℃ at 20 ℃/min for 12 min.

The alkylation reactor in the examples is a fixed bed reactor.

The vectors are described below:

Al₂O₃carrier with specific surface area of 400m²(ii)/g, pore diameter 80 nm;

ZrO₂carrier with specific surface area of 550m²(ii)/g, pore size 70 nm;

SiO₂carrier with specific surface area of 450m²(ii)/g, pore diameter 85 nm;

SiO₂-Al₂O₃carrier with a specific surface area of 500m²(ii)/g, pore diameter of 100nm, and Si/Al atomic ratio of 40.

SiO₂-Al₂O₃Carrier with specific surface area of 600m²(ii)/g, the pore diameter is 90nm, and the atomic ratio of Si to Al is 80.

Examples 1 to 1

2 wt% Ru-4% Ni-6% Cu/modified SiO₂-Al₂O₃Preparation of

At normal temperature, 100g of strip SiO₂-Al₂O₃The carrier (Si: Al atomic ratio 40) was completely immersed in 100ml of a mixed aqueous solution containing 26.0g of ammonium silicofluoride and 1.4g of boric acid for 12 hours to allow adsorption equilibrium, then placed in an oven for 6 hours at 130 ℃ and finally transferred to a muffle furnace for calcination at 500 ℃ for 7 hours to obtain a carrier containing 8% of introduced SiO₂And 0.7% B₂O₃Modified SiO of₂-Al₂O₃And (3) a carrier.

6.9g of ruthenium nitrate, 21.7g of nickel nitrate hexahydrate and 24.8g of copper nitrate trihydrate are dissolved in 100ml of deionized water, the mixture is stirred uniformly, and then the modified SiO is added₂-Al₂O₃Support, impregnationAfter 18h for adsorption equilibrium, the mixture is put into an oven to be baked for 10h at 120 ℃, and finally the mixture is transferred to a muffle furnace to be baked for 6h at 400 ℃. Obtaining 2 wt% Ru-4% Ni-6% Cu/modified SiO₂-Al₂O₃Precursor of catalyst A-1.

Examples 1 to 2

1 wt% Pd-8% Ni-2% Fe/modified SiO₂-Al₂O₃Preparation of

At normal temperature, 100g of strip SiO₂-Al₂O₃The carrier (Si: Al atomic ratio is 80) is completely immersed in 100ml of mixed aqueous solution containing 19.0g of ammonium fluorosilicate and 0.9g of boric acid, the carrier is immersed for 18h to be adsorbed and balanced, then the carrier is placed in an oven to be baked for 9h at 100 ℃, finally the carrier is transferred to a muffle furnace to be baked for 3h at 450 ℃, and the carrier containing 6 percent of introduced SiO is obtained₂And 0.5% B₂O₃Modified SiO of₂-Al₂O₃And (3) a carrier.

2.3g of palladium nitrate, 42.4g of nickel nitrate hexahydrate and 15.4g of ferric nitrate nonahydrate are dissolved in 100ml of deionized water, the mixture is stirred uniformly, and then the modified SiO is added₂-Al₂O₃The carrier is soaked for 14h for adsorption equilibrium, then is put in an oven for baking for 4h at 150 ℃, and finally is transferred to a muffle furnace for baking for 9h at 350 ℃.1 wt% Pd-8% Ni-2% Fe// modified SiO₂-Al₂O₃Precursor of catalyst A-2.

Examples 1 to 3

2.5 wt% Ru-10% Ni-4% Mo/modified Al₂O₃Preparation of

At room temperature, 100g of strip-shaped Al₂O₃The carrier is completely immersed in 100ml of mixed aqueous solution containing 9.3g of ammonium fluosilicate and 1.9g of boric acid, the carrier is immersed for 14h to be adsorbed and balanced, then the carrier is placed in an oven to be dried for 7h at 120 ℃, finally the carrier is transferred to a muffle furnace to be roasted for 8h at 400 ℃, and 3% SiO is obtained₂And 1% of B₂O₃Modified Al of (2)₂O₃And (3) a carrier.

Dissolving 8.2g of ruthenium nitrate, 51.6g of nickel nitrate hexahydrate and 8.5g of ammonium molybdate in 100ml of deionized water, stirring uniformly, and adding the modified Al₂O₃Soaking the carrier for 16h for adsorption equilibrium, and then drying in an oven at 130 deg.C for 6hAnd finally, transferring the muffle furnace, and roasting at 450 ℃ for 7 hours. 2.5 wt% Ru-10% Ni-4% Mo// modified Al was obtained₂O₃Precursor of catalyst A-3.

Examples 1 to 4

0.5 wt% Pd-1% Ru-8% Cu/modified ZrO₂Preparation of

100g of spherical ZrO was put at ordinary temperature₂The carrier is completely immersed in 100ml of mixed aqueous solution containing 15.7g of ammonium fluosilicate and 1.1g of boric acid, the carrier is immersed for 16h until the adsorption is balanced, then the carrier is placed in an oven to be dried for 8h at the temperature of 110 ℃, finally the carrier is transferred to a muffle furnace to be roasted for 10h at the temperature of 300 ℃, and the carrier containing 5 percent of SiO is obtained₂And 0.6% B₂O₃Modified ZrO of₂And (3) a carrier.

1.1g of palladium nitrate, 3.3g of ruthenium nitrate and 32.0g of copper nitrate trihydrate were dissolved in 100ml of deionized water, and the mixture was stirred well, and the above-mentioned modified ZrO was added₂Soaking the carrier for 12h for adsorption balance, then placing the carrier in an oven for baking for 10h at 120 ℃, finally transferring the carrier to a muffle furnace for baking for 10h at 300 ℃. 0.5 wt% Pd-1% Ru-8% Cu/modified ZrO was obtained₂Precursor of catalyst A-4.

Examples 1 to 5

1.5% Ru-10% Cu-3% Zn/modified SiO₂Preparation of

At normal temperature, 100g of spherical SiO₂The carrier is completely immersed in 100ml of mixed aqueous solution containing 22.5g of ammonium fluosilicate and 1.5g of boric acid, the carrier is immersed for 20 hours to be adsorbed and balanced, then the carrier is placed in an oven to be dried for 5 hours at 150 ℃, finally the carrier is transferred to a muffle furnace to be roasted for 5 hours at 600 ℃, and 7 percent of introduced SiO is obtained₂And 0.8% B₂O₃Modified SiO of₂And (3) a carrier.

5.1g of ruthenium nitrate, 40.9g of copper nitrate trihydrate and 14.9g of zinc nitrate are dissolved in 100ml of deionized water, the mixture is stirred uniformly, and then the modified SiO is added₂Soaking the carrier for 20h for adsorption balance, then placing the carrier in an oven for baking for 12h at 120 ℃, finally transferring the carrier to a muffle furnace for baking for 5h at 500 ℃. 1.5% Ru-10% Cu-3% Zn/modified SiO₂Precursor of catalyst A-5.

Comparative example 1

2wt％Ru-4％Ni-6％Cu/SiO₂-Al₂O₃Preparation of

Comparative example 1 differs from example 1-1 in that SiO₂-Al₂O₃Without any modification treatment.

6.9g of ruthenium nitrate, 21.7g of nickel nitrate hexahydrate and 24.8g of copper nitrate trihydrate are dissolved in 100ml of deionized water, stirred uniformly and then 100g of SiO is added₂-Al₂O₃Soaking the carrier for 18h to be adsorbed and balanced, then placing the carrier in an oven to bake for 10h at 120 ℃, finally transferring the carrier to a muffle furnace to bake for 6h at 400 ℃. Obtaining 2 wt% Ru-4% Ni-6% Cu/modified SiO₂-Al₂O₃Precursor of catalyst A-6.

Example 2-1

Loading a bulk volume of 50ml of supported catalyst precursor A-1 into a fixed bed reactor, reducing the supported catalyst precursor A-1 with a mixed gas of 5% of hydrogen and 95% of nitrogen at 300 ℃ for 6h, after the reduction is finished, reducing the reaction temperature to 200 ℃, increasing the system pressure (absolute pressure, the same below) to 40bar and starting feeding, wherein the space velocity is 5.0 l of toluenediamine per liter of catalyst per hour, and the molar ratio of ethylene to toluenediamine is 15: 1, through gas chromatographic analysis, toluene diamine is not detected, the content of diethyl toluene diamine is 99.5 percent, the content of monoethyl toluene diamine is 0.5 percent, the conversion rate of raw materials is 100 percent, and the yield of products is 99.5 percent.

Examples 2 to 2

Loading a bulk volume of 50ml of supported catalyst precursor A-2 into a fixed bed reactor, reducing the supported catalyst precursor A-2 with a mixed gas of 5% of hydrogen and 95% of nitrogen at 200 ℃ for 12h, after the reduction is finished, reducing the reaction temperature to 160 ℃, increasing the system pressure (absolute pressure, the same below) to 35bar and starting feeding, wherein the space velocity is 4.0 l of toluenediamine per liter of catalyst per hour, and the molar ratio of ethylene to toluenediamine is 20: 1, through gas chromatographic analysis, toluene diamine is not detected, the content of diethyl toluene diamine is 99.0 percent, the content of monoethyl toluene diamine is 1.0 percent, the conversion rate of raw materials is 100 percent, and the yield of products is 99.0 percent.

Examples 2 to 3

Loading a bulk volume of 50ml of supported catalyst precursor A-3 into a fixed bed reactor, reducing the supported catalyst precursor A-3 with a mixed gas of 5% of hydrogen and 95% of nitrogen for 10 hours at 250 ℃, after the reduction is finished, reducing the reaction temperature to 240 ℃, increasing the system pressure (absolute pressure, the same below) to 30bar and starting feeding, wherein the space velocity is 7.0 l of toluenediamine per liter of catalyst per hour, and the molar ratio of ethylene to toluenediamine is 18: 1, through gas chromatography analysis, toluene diamine is not detected, the content of diethyl toluene diamine is 97.5%, the content of monoethyl toluene diamine is 2.5%, the conversion rate of raw materials is 100%, and the yield of products is 97.5%.

Examples 2 to 4

Loading a bulk volume of 50ml of supported catalyst precursor A-4 into a fixed bed reactor, reducing the supported catalyst precursor A-4 with a mixed gas of 5% of hydrogen and 95% of nitrogen for 8 hours at 400 ℃, after the reduction is finished, reducing the reaction temperature to 220 ℃, increasing the system pressure (absolute pressure, the same below) to 45bar and starting feeding, wherein the space velocity is 6.0 l of toluenediamine per liter of catalyst per hour, and the molar ratio of ethylene to toluenediamine is 25: 1, according to gas chromatographic analysis, toluene diamine is not detected, the content of diethyl toluene diamine is 98.5%, the content of monoethyl toluene diamine is 1.5%, the conversion rate of raw materials is 100%, and the yield of products is 98.5%.

Examples 2 to 5

Loading a bulk volume of 50ml of supported catalyst precursor A-5 into a fixed bed reactor, reducing the supported catalyst precursor A-5 with a mixed gas of 5% of hydrogen and 95% of nitrogen for 14h at 350 ℃, after the reduction is finished, reducing the reaction temperature to 180 ℃, increasing the system pressure (absolute pressure, the same below) to 50bar and starting feeding, wherein the space velocity is 3.0 l of toluenediamine per liter of catalyst per hour, and the molar ratio of ethylene to toluenediamine is 10: 1, according to gas chromatographic analysis, toluene diamine is not detected, the content of diethyl toluene diamine is 98.7%, the content of monoethyl toluene diamine is 1.3%, the conversion rate of raw materials is 100%, and the yield of products is 98.7%.

Comparative example 2

Loading a bulk volume of 50ml of supported catalyst precursor A-6 into a fixed bed reactor, reducing the supported catalyst precursor A-6 with a mixed gas of 5% of hydrogen and 95% of nitrogen at 300 ℃ for 6h, reducing the reaction temperature to 200 ℃ after the reduction is finished, raising the system pressure (absolute pressure, the same below) to 40bar and starting feeding, wherein the space velocity is 5.0 l of toluenediamine per liter of catalyst per hour, and the ethylene/toluenediamine molar ratio is 15: 1, through gas chromatographic analysis, toluene diamine is not detected, the content of diethyl toluene diamine is 80.0 percent, the content of monoethyl toluene diamine is 3.0 percent, the content of demethylation by-products is 2.0 percent, the content of N-alkylation by-products is 15 percent, the conversion rate of raw materials is 100 percent, and the yield of products is 80.0 percent.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. Not all embodiments are exhaustive. All obvious changes or modifications of the technical solution of the present invention are within the spirit of the present invention.

Claims

1. A supported catalyst for the production of diethyltoluenediamine, said catalyst comprising a modified support and a supported active component; the method is characterized in that the modified carrier is prepared by introducing a soluble silicon-containing compound and a boron-containing compound into the carrier, drying and roasting the carrier to obtain the modified carrier containing SiO obtained by decomposing the soluble silicon-containing compound and the boron-containing compound₂And B₂O₃The modified support of (1);

SiO obtained by decomposition₂The weight of the modified carrier is 3.0-8.0 percent, and B is obtained by decomposition₂O₃Accounting for 0.1 to 3.0 percent of the weight of the modified carrier;

the active component is selected from one or more of Pt, Pd, Ru, Rh and Ir;

based on the total weight of the catalyst, the content of the active component is 0.05-5 wt%;

the soluble silicon-containing compound is ammonium fluorosilicate.

2. The supported catalyst of claim 1, wherein the SiO obtained by decomposition₂Accounting for 4.0 to 6.0 percent of the weight of the modified carrier; b obtained by decomposition₂O₃Accounting for 0.5 to 1.0 percent of the weight of the modified carrier.

3. A supported catalyst according to claim 1 or 2, wherein the active component is selected from one or more of Pt, Pd and Ru; the content of the active component is 0.5-3.0 wt% based on the total weight of the catalyst.

4. The supported catalyst of claim 3, wherein the active component comprises at least Ru; based on the total weight of the catalyst, the content of the active component is 1.0 to 2.5 weight percent.

5. The supported catalyst of claim 1 or 2, wherein the catalyst comprises an auxiliary selected from one or more of Ni, Cu, Fe, Zn, Cr, Co, Ti, V, Mo, Mn, Bi;

the content of the auxiliary agent is 0-15 wt% and is not 0 based on the total weight of the catalyst.

6. The supported catalyst of claim 5, wherein the promoter is selected from one or more of Ni, Cu, Fe, Zn and Mo; based on the total weight of the catalyst, the content of the auxiliary agent is 2.0-10.0 wt%.

7. The supported catalyst of claim 6, wherein the promoter is selected from the group consisting of Ni and/or Cu; based on the total weight of the catalyst, the content of the auxiliary agent is 4.0-8.0 wt%.

8. The supported catalyst of claim 1, wherein the support is porous Al₂O₃、ZrO₂、TiO₂、SiO₂And SiO₂-Al₂O₃One or more of the complexes.

9. The supported catalyst of claim 8, wherein the support is porous SiO₂-Al₂O₃The composite.

10. A process for preparing a supported catalyst according to any one of claims 1 to 9, comprising the steps of:

1) introducing soluble silicon-containing compound and boron-containing compound into a carrier, and drying and roasting to prepare a modified carrier;

11. The method of claim 10 wherein the soluble boron-containing compound is one or more of boric acid, ammonium pentaborate, and ammonium tetraborate.

12. The method of claim 11 wherein the soluble boron-containing compound is boric acid.

13. The method as claimed in claim 11, wherein the roasting temperature in step 1) is 100 ℃ to 700 ℃; the roasting time is 1-10 h;

in the step 3), the roasting temperature is 200-600 ℃; the roasting time is 2-12 h.

14. The method as claimed in claim 13, wherein the roasting temperature in step 1) is 200-600 ℃; the roasting time is 2-8 h;

in the step 3), the roasting temperature is 300-500 ℃; the roasting time is 4-10 h.

15. Use of a catalyst according to any one of claims 1 to 9 or a supported catalyst prepared by a process according to any one of claims 10 to 14 for the preparation of diethyltoluenediamine by alkylation of toluenediamine with ethylene.

16. Use according to claim 15, wherein the molar ratio of ethylene to toluenediamine is (1-50): 1; the reaction temperature is 100 ℃ and 300 ℃, and the reaction pressure is 10bar-70 bar.

17. Use according to claim 16, wherein the molar ratio of ethylene to toluenediamine is (5-35): 1; the reaction temperature is 150 ℃ and 250 ℃, and the reaction pressure is 30-50 bar.

18. Use according to claim 17, wherein the molar ratio of ethylene to toluenediamine is (10-25): 1.

19. use according to claim 15, wherein the reaction is carried out in a fixed bed reactor and the catalyst space velocity is from 0.01 to 15 litres of toluenediamine per litre of catalyst per hour.

20. Use according to claim 19, wherein the catalyst space velocity is from 0.5 to 10 litres of toluenediamine per litre of catalyst per hour.

21. Use according to claim 20, wherein the catalyst space velocity is from 2.0 to 7.0 litres of toluenediamine per litre of catalyst per hour.