WO2018090388A1

WO2018090388A1 - Catalyst for resource utilization of aniline rectification residue and preparation method therefor

Info

Publication number: WO2018090388A1
Application number: PCT/CN2016/107065
Authority: WO
Inventors: 张聪颖; 李鑫; 刘振国; 任树杰; 陈浩; 陈忠英; 倪自林; 王宁宁; 邵仁龙; 张兵; 王小龙; 唐磊; 刘志鹏; 吴健; 王丛; 姜庆梅; 黎源; 华卫琦
Original assignee: 万华化学集团股份有限公司
Priority date: 2016-11-15
Filing date: 2016-11-24
Publication date: 2018-05-24
Also published as: CN108067213A; CN108067213B

Abstract

Provided are a catalyst for resource utilization of a fixed bed aniline rectification residue and a preparation method therefor. The catalyst comprises a carrier and an active component, and optionally a first adjuvant component and a second adjuvant component. The active component comprises Ni and Ru, wherein, based on the total weight of the catalyst, the Ni content is 10% - 40%; and the Ru content is 0.5% - 5%. The catalyst exhibits a relatively high activity and stability during the use in the resource utilization of a fixed bed aniline rectification residue, and cyclohexylamine and dicyclohexylamine can be obtained in a high yield.

Description

Catalyst for resource utilization utilization of aniline rectification residue and preparation method thereof

Technical field

The invention relates to a production method for resource utilization of chemical residue, in particular to a catalyst for resource utilization utilization of aniline rectification residue and preparation method thereof, and continuous production method for resource utilization utilization of aniline rectification residue .

Background technique

Aniline is a colorless oily liquid with strong odor and toxic. It is an important chemical intermediate and is widely used in the production of rubber auxiliaries, dyes, photographic chemicals, pharmaceuticals, pesticides, explosives and polyurethanes. The production methods include phenol amination, iron powder reduction and nitrobenzene catalytic hydrogenation.

Most manufacturers use nitrobenzene catalytic hydrogenation in view of raw material sources, energy consumption and environmental protection. The nitrobenzene catalytic hydrogenation process for aniline is divided into liquid phase method and gas phase method. Due to technical cost and other factors, most aniline production enterprises adopt liquid phase catalytic addition process, and desulfurization of raw material nitrobenzene by oxidation system will be The nitrobenzene and hydrogen are pretreated by mixing, and the reaction is carried out in a fluidized bed reactor, and the catalyst is recycled through the reactor for recycling. Since the reaction has water formation, the crude product (crude aniline) is subjected to extraction and purification after the reaction, unreacted nitrobenzene is recovered, and aniline is obtained by distillation, and the aniline rectification residue is obtained by enrichment in the column. There are two main sources of aniline rectification residue: one is the partial boiling of nitrobenzene in the hydrogenation process due to the excess of hydrogen, and the other is the reaction of the cyclohexanone intermediate formed during the hydrogenation reaction with aniline. The resulting Schiffki aniline rectification residue.

The aniline rectification residue is a black viscous liquid with a pungent odor and contains many aromatic hydrocarbons with a negatively charged π-electron system, such as

), cyclohexylaniline (

), (

Diphenylamine

), 1,2,3,4-tetrahydrocarbazole

), N-p-anilinoaniline (

Phenol, N-o-aniline ring and amine (

), 2-phenylaniline (

), long-chain alkanes, etc., the molecular weight of these substances is high, and if the molecule contains an amino group (—NH ₂ ), then two substances containing the amino group are prone to deamination reaction, resulting in a macromolecular substance containing —NH— . In the presence of nitrobenzene and hydrogen, a certain amount of azo-containing (-N=N-) bonds are also produced.

Such compounds are even oligomers and polymers. Due to the presence of these compounds, the aniline rectification residue has a deep color, a large viscosity, and poor fluidity, and is difficult to be used twice, and is generally used as a fire-resistant material or a waterproof material. The ratio of the amount consumed by these two uses to the total amount of aniline rectification residue is very low. Therefore, most of the aniline rectification residue is treated as a waste liquid, and is treated by incineration, but it generates nitrogen oxides after incineration. The formation of acid rain and pollution of the environment will reduce the output of agriculture and fisheries.

Chinese patent CN201310396100.6 provides a catalyst which can be used for resource utilization of fixed bed aniline rectification residue and a preparation method thereof, but there is no practical industrial production method. The catalyst preparation method reported in this patent is complicated, the industrialization amplification is low in achievability, and the catalyst life is short, which will result in high overall cost of the catalyst. Because of its resource utilization, the use of aniline rectification residue is only 50%-70% utilization, and it is difficult to achieve industrial application due to low economic efficiency.

Summary of the invention

In view of the above technical deficiencies, the present invention provides a catalyst which can be used for resource utilization of aniline rectification residue, a preparation method thereof, and a method for resource utilization of aniline rectification residue, which is used for resource utilization of aniline rectification residue Utilizing, it has extremely high selectivity and stability.

In order to achieve an aspect of the above object, the technical scheme for the catalyst for resource utilization utilization of aniline rectification residue provided by the present invention is as follows:

A catalyst for resource utilization of an aniline rectification residue, the catalyst comprising a carrier and an active component; the active component comprising Ni and Ru, wherein the Ni content is 8%-40% based on the total weight of the catalyst , preferably 10% to 25%, such as 15% or 20%; Ru content is 0.5% to 5%, It is preferably from 1.5% to 3%, such as 2% or 2.5%. In one embodiment, the balance is a carrier.

The catalyst of the present invention optionally further comprises a first auxiliary component and a second auxiliary component, and in the present invention, "optional" means that it may or may not be present. Wherein, the first auxiliary component is one or more of Fe, Mo, Cr, Cu and Zn, and the content is 2%-15%, preferably 3%-10%, based on the total weight of the catalyst, For example, 4%, 6% or 8%; the second auxiliary component is one or more of Re, Zr, Y and Ce, and the content is 1%-10% based on the total weight of the catalyst, preferably 2%-5%, such as 3% or 4%. In one embodiment, the balance is a carrier.

In the present invention, the support may be a porous oxide support for a hydrocracking catalyst commonly used in the art, such as Al ₂ O ₃ or MgO, and the like. The preparation method of the above porous oxide is well known in the art. For example, for Al ₂ O ₃ , Al ₂ (SO ₄ ) _{3 is} formulated into an aqueous solution, and an alkali solution such as NH ₃ ·H ₂ O is added for precipitation reaction to obtain Al(OH). ₃ precipitate, and then filtered, washed, and dried to obtain the aluminum hydroxide product, which is formed by extrusion of a binder, and calcined by firing (for example, 400 to 500 ° C) to obtain an Al ₂ O ₃ carrier.

In a preferred embodiment of the present invention, the carrier is an alkaline earth metal oxide modified Al ₂ O ₃ , wherein the alkaline earth metal oxide: alumina molar ratio may be 1:4 to 4:1, such as 1 2 to 2:1, for example, 1:1.5 or 1:1; preferably, the alkaline earth metal oxide is one or more of MgO, CaO, SrO, and BaO; further preferably, the alkaline earth metal is oxidized The substance is MgO and/or CaO. For the alkaline earth metal oxide-modified Al ₂ O ₃ carrier of the present invention, it is preferably also prepared by the following steps:

a, the salt solution of the alkaline earth metal and the salt solution of aluminum are dissolved in water according to the ratio to obtain a mixed salt solution; the alkaline earth metal element and the aluminum element in the mixed salt solution are coprecipitated by the alkali solution;

Further preferably, during the precipitation process, the mixed salt solution is injected into the sedimentation tank with the stirring device and the alkaline solution, and the pH in the precipitation tank is maintained at 6.5-7.5, and the precipitation temperature is maintained. After 55 to 65 ° C; after the completion of the precipitation, continue to maintain the stirring speed and precipitation temperature, so that the precipitated product is aged for at least 4h;

b. The precipitate is filtered and washed, and the washed precipitate is dried, calcined and crushed to obtain an oxide powder of an alkaline earth metal and aluminum; the oxide powder is mixed with a binder, molded, and then calcined to obtain the carrier.

The shape of the carrier of the present invention may be in various shapes, and the specific shape of the carrier may be designed according to the reactor (for example, a kettle type, a fixed bed, a fluidized bed, a tube tube type or a bubble column type according to actual needs). The selection includes, but is not limited to, one or more of a sheet shape, a strip shape, and a clover shape.

The above catalyst of the present invention is used in the resource utilization of aniline distillation residue. The reaction process of the catalyst for treating aniline rectification residue of the invention belongs to hydrocracking, mainly by C-C, C-N, C=C, N=N molecular chain in the high molecular weight substance in the rectification residue by hydrocracking reaction. Interruption, reduce the viscosity of the system, and obtain small molecular substances such as cyclohexylamine and dicyclohexylamine to facilitate subsequent separation operations. In addition, the catalyst of the present invention does not open the ring in the small molecule, and the reaction principle can be referred to the following reaction formula:

The components in the catalyst of the invention are combined with each other to make the catalyst have high activity and stability. Although the main active metal Ni in the catalyst has good catalytic activity, it is easy to be lost, sintered and accumulated in the high temperature reaction. Carbon has reduced activity and is prone to S poisoning. Especially under alkaline conditions, the activity is obviously reduced. Adding proper Ru element can effectively improve the activity of the catalyst, and also greatly inhibit the breakage of CN bond during the fracture process, ensuring the maximum CN and improving the selectivity of the catalyst. Thereby, the effective amine yield in the product is greatly improved, and the first promoter component such as Fe, Mo, Cr, Cu and Zn is added to reduce the carbon deposition and the degree of sintering, thereby improving the high temperature stability and the life of the catalyst. The second promoter component Re, Zr, Y, Ce can increase the dispersion of the active metal and increase the active center of the catalyst. However, the traditional Al ₂ O ₃ catalyst has strong acidity and is prone to carbon deposition. The modification of Al ₂ O ₃ by alkaline earth metal modification not only reduces the surface acidity of the Al ₂ O ₃ carrier, but also significantly reduces the carbon deposition and reduces the carbon deposition. Excessive hydrogenolysis opens the ring side reaction.

In order to achieve another aspect of the above object, the method for preparing the above catalyst provided by the present invention employs the following technical solutions:

A method for preparing a catalyst for resource utilization of aniline rectification residue, the preparation method comprising the following steps:

1) Preparation of a metal salt solution: weighing a metal salt in proportion and adding deionized water to prepare a metal salt solution; wherein the metal salt comprises a metal salt of the active component, and optionally a first auxiliary agent group a metal salt that is divided into a second auxiliary component;

2) adsorption: using the carrier to adsorb the metal salt solution obtained in step 1) to obtain a carrier after adsorption;

3) Drying, calcination, and reduction to obtain a catalyst.

In the step 1), the metal salt in the metal salt solution includes, but is not limited to, one or more of a metal halide, a nitrate, an organic acid salt, and the like, preferably a nitrate or formic acid of the metal. One or more of a salt, an acetate, an oxalate, and the like, more preferably a nitrate of the metal.

The ratio of the amount of each metal element in the metal salt can be determined according to the ratio of each active component and the auxiliary component in the foregoing catalyst, wherein the metal salt solution is an aqueous solution in which the metal salt is dissolved in water to form a metal salt, and the concentration thereof is It may be from 5 to 60% by weight, such as 20% by weight, 30% by weight or 40% by weight.

In step 2), the method of adsorbing the metal salt solution by means of a carrier is well known in the art, for example, the carrier may be impregnated with the metal salt solution obtained in step 1) or the metal salt solution obtained in step 1) may be sprayed. On the carrier, the adsorbed carrier is obtained. Those skilled in the art understand that the concentration of the solution, the immersion time or the amount of spray, etc. can be adjusted to adjust the gold in the carrier. The adsorption amount of the salt is, in turn, the content of the active component or the auxiliary agent in the catalyst, and the adsorption process can also be carried out once or repeatedly. In one embodiment, the volume ratio of the metal salt solution to the carrier can also be controlled within a suitable range, so that the metal salt solution can be substantially completely absorbed by the carrier or the solid solution mixture of the obtained carrier and the solution can be evaporated to remove Excess solvent.

The impregnation process can be carried out in various ways. For example, the carrier may be impregnated with a mixture of various metal salt solutions or various different metal salt solutions, or the carriers may be sequentially treated with different metal salt solutions. Impregnation; those skilled in the art understand that the impregnation process and the spraying process can be accomplished in one portion or in multiple steps.

In the step 3), the obtained carrier is dried and calcined to obtain a catalyst. The above treatment process is a common treatment process in the art, for example, drying at 70 ° C - 120 ° C, and baking at 300 ° C - 500 ° C.

It is understood by those skilled in the art that the catalyst precursor obtained by the drying and calcination treatment of the present invention has an active component and an auxiliary component in the form of an oxide, and needs to be subjected to a reduction treatment before use to activate the catalyst for use. Subsequent hydrocracking to produce a reaction of cyclohexylamine and dicyclohexylamine. The above reduction treatment process is a common treatment process in the art, for example, the catalyst is reduced at 200 ° C to 400 ° C; the reduction process is carried out under a reducing atmosphere, and the reduction time may be 4 h to 16 h to make the oxidation state. The active component and the auxiliary component are reduced to the active metal state. a reducing atmosphere such as pure hydrogen or a mixture of an inert gas and hydrogen, including but not limited to nitrogen, helium, neon, argon or helium, preferably nitrogen; based on the total volume of inert gas and hydrogen The inert gas may have a volume content of 5% to 95%, such as 50% to 85%.

In order to achieve still another aspect of the above object, the method for resource utilization of the aniline rectification residue provided by the present invention adopts the following technical solutions:

A method for recycling aniline rectification residue, wherein the aniline rectification residue is diluted by using liquid ammonia or a small molecule organic amine as a diluent; and the diluted aniline is diluted in the presence of hydrogen and a catalyst The residue is subjected to hydrotreatment to obtain cyclohexylamine and dicyclohexylamine.

In the method of the present invention, the aniline rectification residue is diluted with a diluent, thereby A preferably well-flowing diluent is obtained. Preferably, the volume ratio of the diluent to the aniline rectification residue is from 1:4 to 4:1, further preferably from 1:2 to 2:1, such as 1:1. The small molecule organic amine is an organic amine having a C atom number of not more than 5. Preferably, the small molecule organic amine is one or more of methylamine, dimethylamine, ethylamine, trimethylamine and ethylenediamine. . The use of the diluent of the present invention is advantageous for further improving the conversion utilization of the aniline rectification residue.

The production method of the present invention may be carried out batchwise or continuously, preferably continuously. The hydrocracking of the aniline rectification residue by continuous process can be carried out in the form of a liquid phase reaction in a fixed bed or a fluidized bed reactor.

The reaction temperature of the hydrocracking reaction of the present invention may be from 150 ° C to 250 ° C, preferably from 180 ° C to 230 ° C, such as 200 ° C; the reaction pressure (absolute pressure) may be from 1 MPa to 40 MPa, preferably from 10 MPa to 25 MPa, for example 15 or 20 MPa, wherein the volumetric space velocity of the liquid phase feed of the diluent is 0.1 to 2.0 h ^-1 , preferably 0.3 to 1.5 h ^-1 , and the amount of hydrogen is 500 to 3000 h ^-1 , preferably 1000 to 2000 h ^-1 .

The beneficial effects of the invention are:

The catalyst prepared by the invention has high activity and high selectivity, the selectivity of cyclohexylamine and dicyclohexylamine is as high as 80% to 95%, and has good stability, and the product selectivity does not decrease after 500 hours of reaction. In addition, due to the use of supported catalyst preparation technology, the catalyst production cost and the achievability of industrial large-scale production are greatly improved, and the catalyst stability is also significantly improved, which makes the overall economic efficiency of the technology and provides an industry. The practical and continuous production method is conducive to industrial application.

detailed description

The invention is further described in detail below by way of specific examples, but it should be understood that the scope of the invention is limited to the following examples. Various alterations and modifications may be made without departing from the spirit and scope of the invention.

The reactor used in the examples was a fixed bed reactor measuring 100 cm in length × 25 mm in inner diameter, and the reaction product was internally coded by Shimadzu GC-2014 gas chromatograph (hydrogen ion flame (FID) detector). Method analysis, the analytical column is SE-30 capillary column (φ0.30mm×30m), gasification chamber 270°C, detector 270°C, column temperature 70°C, constant temperature 1min, then increase to 240°C at 40°C/min , and then keep warm for 5min.

In the examples, the aniline rectification residue is derived from an aniline rectification apparatus of Wanhua Chemical (Ningbo) Co., Ltd. The remaining reagents, if not explicitly stated, were analytically pure.

Unless otherwise specified in the following examples, the contents are all by mass.

Example 1

Each group of drugs was weighed and dissolved in distilled water according to the ratio shown in Table 1 to obtain five groups of solutions having a concentration of about 2.5 mol/L, which were respectively recorded as solutions A1, A2, A3, A4 and A5. Further, sodium hydroxide having a concentration of 7.6 mol/L was taken as the solution B.

The water in the precipitation tank was heated to 60 ° C, and the solutions A1 and B were simultaneously added dropwise to the precipitation tank. During the preparation, the pH and precipitation temperature were maintained at 6.5-7.5 and 60 °C, respectively. After the end of the precipitation, the stirring speed and the precipitation temperature were kept unchanged, aged for 8 hours, filtered and washed to neutrality, and the precipitate was placed in an oven at 110 ° C for 12 hours. After the drying was completed, it was baked in an air atmosphere at 400 ° C for 4 hours. The powder was crushed to 400-600 mesh to obtain a magnesia-modified alumina carrier powder D1 in which the molar ratio of magnesium oxide to alumina was about 1:1.6. The modified powder D2 having a molar ratio of calcium oxide to alumina of about 1.5:1, the modified powder D3 having a molar ratio of cerium oxide to alumina of about 2:1, and the molar ratio of cerium oxide to aluminum oxide are about 1:2 modified powder D4, and alumina powder D5.

The above D1-D5 powders were respectively mixed with a binder (aluminum sol) in a mass ratio of 9:1, and then extruded into a strip having a diameter of about 1.5 mm and a length of about 10 mm, and finally dried, and at about 550. Calcination at °C gave carriers Z1, Z2, Z3, Z4 and Z5.

Table 1 (molar ratio)

组group	硝酸镁/molMagnesium nitrate/mol	甲酸钙/molCalcium formate/mol	氯化钡/molBarium chloride / mol	氯化锶/molBarium chloride / mol	硝酸铝/molAluminum nitrate/mol
11	11	—-	—-	—-	3.23.2
22	—-	33	—-	—-	22
33	—-	—-	22	—-	22
44	—-	—-	—-	11	44

5

-

4

Note: “—” in the table means not added.

Example 2

80 ml of a nitrate immersion liquid containing 15 g of Ni, 0.5 g of Ru, 0.5 g of Fe, 1 g of Mo and 1 g of Zn, 0.5 g of Re, and 0.5 g of Ce was placed, and 81 g of the carrier Z1 was poured into the above immersion liquid, and adsorbed at room temperature for 2 hours. Basically completely absorbed. After the above-mentioned adsorbed carrier Z1 is dried, it is calcined at about 475 ° C for 12 hours, then cooled, and then subjected to a reductive activation treatment at about 350 ° C under a reducing atmosphere, and after the reduction is completed, a Ni-containing 15 wt% and a Ru 0.5 wt% are obtained. Catalyst C1 of Fe 0.5 wt%, Mo 1 wt%, Zn 1 wt%, Re 0.5 wt%, and Ce 0.5 wt%.

The fixed bed reactor was filled with a catalyst C1 having a bulk volume of 10 ml; the liquid ammonia and the aniline rectification residue were mixed in a volume ratio of 1:2 to obtain a diluent, and the reaction temperature was adjusted to 150 ° C, and the system pressure (absolute pressure, The same as below) rose to 15MPa and began to feed, the diluent airspeed was 0.3h ^-1 , H ₂ flow was 200ml / min, after 10h reaction began sampling analysis, cyclohexylamine and dicyclohexylamine content was 31% , 58%. After 500 hours, the content of cyclohexylamine and dicyclohexylamine was 28% and 59%, respectively.

Example 3

75 ml of a nitrate immersion liquid containing 10 g of Ni, 3 g of Ru, 0.5 g of Fe, 0.5 g of Cr, 5 g of Cu and 5 g of Zr was placed, and 76 g of the carrier Z1 was poured into the above immersion liquid, and adsorbed at room temperature for 2 hours, and the solution was substantially completely absorbed. After the above-mentioned adsorbed carrier Z1 is dried, it is calcined at about 500 ° C for 10 h, then cooled, and then subjected to a reductive activation treatment at about 400 ° C under a reducing atmosphere. After the reduction is completed, Ni-containing 10 wt%, Ru 3 wt%, Cr 2 wt%, Cu 5 wt%, and Zr 5 wt% of catalyst C2.

The fixed bed reactor is filled with a catalyst C2 having a bulk volume of 10 ml; the methylamine and the aniline rectification residue are mixed in a volume ratio of 1:1 to obtain a diluent, and the reaction temperature is adjusted to 200 ° C, and the system pressure (absolute pressure, The same as below) rose to 15MPa and began to feed, the diluent airspeed was 1.0h ^-1 , H ₂ flow was 300ml / min, after 10h reaction began sampling analysis, cyclohexylamine and dicyclohexylamine content was 43% 51%. After 500 hours, the content of cyclohexylamine and dicyclohexylamine was 39% and 52%, respectively.

Example 4

80 ml of a nitrate immersion liquid containing 18 g of Ni, 2 g of Ru, 2 g of Mo and 1 g of Y was placed, and 77 g of the carrier Z1 was poured into the above immersion liquid, and adsorbed at room temperature for 2 hours, and the solution was substantially completely absorbed. After the above-mentioned adsorbed carrier Z1 is dried, it is calcined at about 425 ° C for 8 hours, then cooled, and then subjected to a reduction activation treatment at about 300 ° C under a reducing atmosphere. After the reduction is completed, Ni-containing 18 wt%, Ru 2 wt%, Mo 2 wt% and Y 1 wt% of catalyst C3.

The fixed bed reactor is filled with a catalyst C3 having a bulk volume of 10 ml; the dimethylamine and the aniline rectification residue are mixed in a volume ratio of 1:2 to obtain a diluent, and the reaction temperature is adjusted to 230 ° C, and the system pressure (absolute pressure) , the same below) rose to 20MPa and began to feed, the diluent airspeed was 1.5h ^-1 , H ₂ flow was 400ml / min, after 10h reaction began sampling analysis, cyclohexylamine and dicyclohexylamine content were 29 %, 66%. After 500 hours, the content of cyclohexylamine and dicyclohexylamine was 26% and 62%, respectively.

Example 5

80 ml of a nitrate immersion liquid containing 25 g of Ni, 0.5 g of Ru, 1 g of Cr, 2 g of Zn, 0.5 g of Re and 1 g of Y was placed, and 70 g of the carrier Z2 was poured into the above immersion liquid, and adsorbed at room temperature for 2 hours, the solution was substantially completely absorbed. After the above-mentioned adsorbed carrier Z2 is dried, it is calcined at about 425 ° C for 8 hours, then cooled, and then subjected to a reduction activation treatment at about 300 ° C under a reducing atmosphere, and after the reduction is completed, a Ni-containing 25 wt% and a Ru 0.5 wt% are obtained. , C1 wt%, Re 0.5 wt%, and Y 1 wt% of catalyst C4.

The fixed bed reactor is filled with a catalyst C4 having a bulk volume of 10 ml; the diethylamine and the aniline rectification residue are mixed in a volume ratio of 2:1 to obtain a diluent, and the reaction temperature is adjusted to 230 ° C, the system pressure (absolute pressure, The same as below) rose to 20MPa and began to feed, the diluent airspeed was 1.5h ^-1 , H ₂ flow was 300ml / min, after 10h reaction began sampling analysis, cyclohexylamine and dicyclohexylamine content of 35% 57%. After 500 hours, the content of cyclohexylamine and dicyclohexylamine was 37% and 54%, respectively.

Example 6

80 ml of a nitrate immersion liquid containing 12 g of Ni, 5 g of Ru, 1 g of Fe, 2 g of Cu, 1.5 g of Zr and 0.5 g of Ce was placed, and 78 g of the carrier Z3 was poured into the above immersion liquid, and adsorbed at room temperature for 2 hours, and the solution was substantially completely absorbed. After the above-mentioned adsorbed carrier Z3 is dried, it is calcined at about 425 ° C for 8 hours, then cooled, and then subjected to a reduction activation treatment at about 300 ° C under a reducing atmosphere, and after the reduction is completed, a Ni-containing 12 wt%, Ru 5 wt%, Fe1 wt is obtained. Catalyst C5 of %, Cu 2 wt%, Zr 1.5 wt%, and Ce 0.5 wt%.

The fixed bed reactor was filled with a catalyst C5 having a bulk volume of 10 ml; the trimethylamine and the aniline rectification residue were mixed in a volume ratio of 1:1 to obtain a diluent, and the reaction temperature was adjusted to 230 ° C, and the system pressure (absolute pressure, The same as below) rose to 20MPa and began to feed, the dilution airspeed was 1h ^-1 , H ₂ flow was 300ml / min, after 10h reaction began sampling analysis, the content of cyclohexylamine and dicyclohexylamine were 29%, 53%. After 500 hours, the content of cyclohexylamine and dicyclohexylamine was 29% and 53%, respectively.

Example 7

80 ml of a nitrate immersion liquid containing 20 g of Ni, 1 g of Ru, 3 g of Cr and 2 g of Ce was placed, and 74 g of the carrier Z4 was poured into the above immersion liquid, and adsorbed at room temperature for 2 hours, and the solution was substantially completely absorbed. After the above-mentioned adsorbed carrier Z4 is dried, it is calcined at about 425 ° C for 8 hours, then cooled, and then subjected to a reduction activation treatment at about 300 ° C under a reducing atmosphere, and after the reduction is completed, a Ni-containing 20 wt%, Ru1 wt%, Cr3 wt is obtained. % and Ce 2 wt% of catalyst C6.

The fixed bed reactor is filled with a catalyst C6 having a bulk volume of 10 ml; the ethylene diamine and the aniline rectification residue are mixed in a volume ratio of 2:1 to obtain a diluent, and the reaction temperature is adjusted to 230 ° C, and the system pressure (absolute pressure) , the same below) rose to 20MPa and began to feed, the diluent airspeed was 1.5h ^-1 , H ₂ flow was 300ml / min, after 10h reaction began sampling analysis, cyclohexylamine and dicyclohexylamine content of 18 %, 75%. After 500 hours, the content of cyclohexylamine and dicyclohexylamine was 15% and 71%, respectively.

Example 8

The difference from Example 2 is that the carrier used is Z5 and the others are the same.

After 10 hours of reaction, sampling analysis was started, and the contents of cyclohexylamine and dicyclohexylamine were 31% and 58%, respectively. After 200 hours, the content of cyclohexylamine and dicyclohexylamine was 29% and 58%, respectively. After 500 hours, samples were analyzed and the contents of cyclohexylamine and dicyclohexylamine were 22% and 53%, respectively.

Comparative example 1

The difference from Example 4 is that the nitrate immersion liquid does not contain strontium, and the others are the same.

After 10 hours of reaction, sampling analysis was started, and the contents of cyclohexylamine and dicyclohexylamine were 17% and 33%, respectively.

Conclusion: It can be seen from the above that the specific combination of active components nickel and ruthenium in the catalyst of the invention can greatly improve the activity and selectivity of the catalyst, and the selectivity of cyclohexylamine and dicyclohexylamine is as high as 80% to 95%; The catalyst of the invention has good stability, and the product selectivity has not decreased after 500 hours of reaction.

Claims

A catalyst for resource utilization of an aniline rectification residue, the catalyst comprising a carrier and an active component; the active component comprising Ni and Ru, wherein the Ni content is 8%-40% based on the total weight of the catalyst The Ru content is from 0.5% to 5%; preferably, the Ni content is from 10% to 25%; and the Ru content is from 1.5% to 3%.
The catalyst according to claim 1, wherein the catalyst further comprises a first auxiliary component and a second auxiliary component, wherein

The first auxiliary component is one or more of Fe, Mo, Cr, Cu and Zn, and the content is 2%-15%, preferably 3%-10%, based on the total weight of the catalyst;

The second auxiliary component is one or more of Re, Zr, Y and Ce, and the content is from 1% to 10%, preferably from 2% to 5%, based on the total weight of the catalyst.
The catalyst according to claim 1 or 2, wherein the carrier is an alkaline earth metal oxide-modified Al 2 O 3 , wherein the alkaline earth metal oxide:alumina molar ratio is 1:4 to 4:1. Preferably, the alkaline earth metal oxide is one or more of MgO, CaO, SrO and BaO; further preferably, the alkaline earth metal oxide is MgO and/or CaO.
The catalyst according to claim 3, wherein the carrier is prepared by the following steps:

a, the salt solution of the alkaline earth metal and the salt solution of aluminum are dissolved in water according to the ratio to obtain a mixed salt solution; the alkaline earth metal element and the aluminum element in the mixed salt solution are coprecipitated by the alkali solution;

Preferably, during the precipitation process, the mixed salt solution and the alkali solution are simultaneously injected into the precipitation tank containing the water and the stirring device, so that the pH in the precipitation tank is maintained at 6.5-7.5, and the precipitation temperature is maintained at 55~65 ° C; after the completion of the precipitation, continue to maintain the stirring speed and precipitation temperature, so that the precipitated product is aged for at least 4h;

b. The precipitate is filtered and washed, and the washed precipitate is dried, calcined and crushed to obtain an oxide powder of an alkaline earth metal and aluminum; the oxide powder is mixed with a binder, molded, and then calcined to obtain the carrier.
A method of preparing a catalyst according to any one of claims 1 to 4, comprising the steps of:

1) Preparation of a metal salt solution: weighing a metal salt in proportion and adding deionized water to prepare a metal salt solution; wherein the metal salt comprises a metal salt of the active component, and optionally a first auxiliary agent group a metal salt that is divided into a second auxiliary component;

2) adsorption: using the carrier to adsorb the metal salt solution obtained in step 1) to obtain a carrier after adsorption;

3) Drying, calcination, and reduction to obtain a catalyst.
The method according to claim 5, wherein the metal salt is one or more of a metal halide, a nitrate and an organic acid salt, preferably a nitrate or formate of the metal. One or more of acetate, oxalate, and more preferably a metal nitrate.
The use of the catalyst according to any one of claims 1 to 4, or the catalyst prepared by the method according to any one of claims 5 to 6, for the utilization of aniline rectification residue.
A method for recycling aniline rectification residue, characterized in that the aniline rectification residue is diluted by using liquid ammonia or a small molecule organic amine as a diluent; and the diluted aniline in the presence of hydrogen and a catalyst The rectification residue is hydrotreated to obtain cyclohexylamine and dicyclohexylamine; wherein the catalyst is the catalyst according to any one of claims 1 to 4 or the catalyst prepared according to the method of claim 5 or 6. .
The method according to claim 8, wherein the small molecule organic amine is one or more of methylamine, dimethylamine, ethylamine, trimethylamine and ethylenediamine; preferably, a diluent and The volume ratio of the aniline rectification residue is 1:4 to 4:1.
The method according to claim 8 or 9, wherein the hydrotreating reaction is carried out in a fixed bed reactor, wherein the volumetric space velocity of the liquid phase feed is 0.1 to 1.5 h -1 and the reaction pressure is 1 to 25MPa, the reaction temperature is between 150 and 250 ° C, and the volume ratio of the amount of hydrogen to the amount of aniline rectification residue is 500 to 3000:1.