阅读说明：本技术 一种氧化钛-氧化铝复合载体及其制备方法和应用 (Titanium oxide-aluminum oxide composite carrier and preparation method and application thereof ) 是由 杜周 张富春 季静 纪玉国 熊凯 任玉梅 于 2020-05-12 设计创作，主要内容包括：本发明公开了一种氧化钛-氧化铝复合载体及其制备方法和应用。该氧化钛-氧化铝复合载体的制备方法包括：(1)将氧化铝、偏钛酸和溶剂进行混合,得到混合物I；(2)将所述混合物I进行高能球磨,得到中值粒径小于0.1μm的混合物II；(3)将所述混合物II进行干燥,再将所得的干燥产物与酸液进行混合,并依次进行成型、烘干和焙烧。该制备方法所使用的钛源成本低,制备过程较少污染,且得到的氧化钛-氧化铝复合载体中的TiO-(2)分布均匀。(The invention discloses a titanium oxide-aluminum oxide composite carrier and a preparation method and application thereof. The preparation method of the titanium oxide-aluminum oxide composite carrier comprises the following steps: (1) mixing alumina, metatitanic acid and a solvent to obtain a mixture I; (2) carrying out high-energy ball milling on the mixture I to obtain a mixture II with the median particle size of less than 0.1 mu m; (3) drying the mixture II, mixing the obtained dried product with acid liquor, and sequentially forming, drying and bakingAnd (6) burning. The titanium source used by the preparation method has low cost and less pollution in the preparation process, and the TiO in the obtained titanium oxide-aluminum oxide composite carrier 2 The distribution is uniform.)

1. A preparation method of a titanium oxide-alumina composite carrier comprises the following steps:

(1) mixing alumina, metatitanic acid and a solvent to obtain a mixture I;

(2) carrying out high-energy ball milling on the mixture I to obtain a mixture II with the median particle size of less than 0.1 mu m;

(3) and drying the mixture II, mixing the obtained dried product with acid liquor, and sequentially forming, drying and roasting.

2. The method as claimed in claim 1, wherein the specific surface area of the alumina is 150-300m²The pore volume is 0.6-1.2mL/g, preferably 0.8-1 mL/g.

3. A process according to claim 1 or 2, characterized in that the weight ratio between alumina and metatitanic acid is (5-10): 1, preferably (5-7): 1;

preferably, the weight ratio of the total weight of alumina and metatitanic acid to solvent is 5: (1-5);

more preferably, the solvent is one or more of deionized water, ethanol, and methanol.

4. The method of any one of claims 1 to 3, wherein the conditions of the high energy ball mill comprise: the time is 6-10h, the revolution speed of the ball mill is 30-350r/min, and the rotation speed of the ball mill is 70-670 r/min;

preferably, the high energy ball milling is a stirred ball milling, a vibratory ball milling or a planetary ball milling, more preferably a planetary ball milling.

5. The method according to any one of claims 1 to 4, wherein the drying conditions comprise: the temperature is 110-150 ℃, preferably 110-130 ℃, and the time is 2-16h, preferably 3-12 h.

6. The method according to any one of claims 1 to 5, wherein the solute in the acid solution is an organic acid and/or an inorganic acid; and/or the solvent in the acid solution is deionized water;

preferably, the concentration of solute in the acid liquor is 0.5-4 wt%;

preferably, the weight ratio of the acid liquid to the dried product, calculated as the solvent, is (1-4): 5, preferably (2-4): 5;

more preferably, the organic acid is one or more of acetic acid, oxalic acid, citric acid and tartaric acid;

more preferably, the inorganic acid is one or more of hydrochloric acid, sulfuric acid and nitric acid, more preferably nitric acid.

7. A method according to any of claims 1-6, characterized in that the method of forming is extrusion.

8. The method according to any one of claims 1 to 7, wherein the drying conditions include: the temperature is 110-150 ℃, preferably 110-130 ℃, and the time is 2-16h, preferably 3-12 h;

preferably, the conditions of the calcination include: the temperature is 500-900 ℃, preferably 550-800 ℃ and the time is 3-16h, preferably 4-12 h.

9. The titania-alumina composite support prepared by the method of any one of claims 1 to 8.

10. Use of the titania-alumina composite support of claim 9 and/or the titania-alumina composite support prepared according to the method of any one of claims 1 to 8 in pyrolysis gasoline hydrogenation and DCC pyrolysis naphtha hydrogenation.

Technical Field

The invention belongs to the field of composite oxides, and particularly relates to a titanium oxide-aluminum oxide composite carrier and a preparation method and application thereof.

Background

TiO₂The hydrogenation catalyst developed as the carrier has the characteristics of high activity, good low-temperature activity, strong anti-poisoning property and the like, but TiO₂The catalyst support also has some weaknesses, such as relatively small specific surface area, easy conversion of active anatase into inert rutile structure at high temperature, poor mechanical strength and weak acidity, generally through TiO formation₂-Al₂O₃And the composite oxide is used as a carrier to overcome the defects and reach the standard of industrial application. Conventional industrial production of TiO-containing₂The method for preparing the composite carrier comprises an impregnation method, a coprecipitation method and a kneading method, wherein the impregnation method mainly adopts organic matters of titanium such as tetraethyl titanate, tetrabutyl titanate and the like as active components to impregnate the formed alumina, the coprecipitation method of the organic matters can adopt titanium chloride or metatitanic acid dissolved by concentrated sulfuric acid as a titanium source, and the methods need to use an expensive organic titanium source or pre-treat the metatitanic acid by concentrated acid and/or concentrated alkali, so that the problems of corrosion of pipelines and containers can occur, and anions influencing subsequent production can be generated, so that the production cost is high, and pollution emission is caused. Preparation of TiO-containing materials by kneading₂With a content of metatitanic acidIncrease height and appear TiO in the composite carrier₂Uneven distribution, and the surface activity of the carrier is inferior to that of the catalyst prepared by an impregnation method or a coprecipitation method, thereby influencing the hydrogenation activity and stability of the catalyst under the condition of high space velocity.

Therefore, the prior art for preparing the titanium oxide-alumina composite carrier has the defects of expensive titanium source, corrosion of pipelines and containers, pollutant generation and TiO in the titanium oxide-alumina composite carrier₂Uneven distribution and thus influence the hydrogenation activity and stability.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a titanium oxide-alumina composite carrier, a preparation method and an application thereof aiming at the defects of the prior art, wherein the titanium source used in the preparation method has low cost, so that the preparation cost is reduced, the pollution in the preparation process is small, the requirement on equipment is low, and the TiO in the obtained titanium oxide-alumina composite carrier₂The distribution is uniform, and the hydrogenation catalyst and the hydrogenation protective agent prepared by the titanium oxide-alumina composite carrier have the advantages of high hydrogenation activity and good stability.

To this end, a first aspect of the present invention provides a method for preparing a titania-alumina composite carrier, comprising:

(1) mixing alumina, metatitanic acid and a solvent to obtain a mixture I;

(2) carrying out high-energy ball milling on the mixture I to obtain a mixture II with the median particle size of less than 0.1 mu m;

(3) and drying the mixture II, mixing the obtained dried product with acid liquor, and sequentially forming, drying and roasting.

According to some embodiments of the preparation method of the present invention, the mixing order of the alumina, the metatitanic acid, and the solvent is for the purpose of enabling sufficient mixing, and it is preferable that the alumina and the metatitanic acid are mixed, added to the solvent, and mixed.

According to some embodiments of the preparation method of the present invention, the specific surface area of the alumina is 150-300m²(ii) in terms of/g. For example 150m²/g、160m²/g、170m²/g、180m²/g、190m²/g、200m²/g、210m²/g、220m²/g、230m²/g、240m²/g、250m²/g、260m²/g、270m²/g、280m²/g、290m²/g、300m²(iv)/g, and any value between any two of the foregoing values.

According to some embodiments of the preparation method of the present invention, the alumina has a pore volume of 0.6 to 1.2mL/g, preferably 0.8 to 1 mL/g. Such as 0.8mL/g, 0.9mL/g, 1mL/g, and any value therebetween.

According to some embodiments of the method of preparing of the present invention, the alumina is a powder, i.e. alumina powder.

According to some embodiments of the preparation method of the present invention, the weight ratio of alumina to metatitanic acid is (5-10): 1, preferably (5-7): 1.

according to some embodiments of the method of preparing of the present invention, the weight ratio of the total weight of alumina and metatitanic acid to the solvent is 5: (1-5).

According to some embodiments of the preparation method of the present invention, the solvent may be any solvent capable of sufficiently dissolving alumina and metatitanic acid, and preferably, the solvent is one or more of deionized water, ethanol, and methanol.

According to some embodiments of the method of making of the present invention, the conditions of the high energy ball milling comprise: the time is 6-10h, the revolution speed of the ball mill is 30-350r/min, and the rotation speed of the ball mill is 70-670 r/min. The time, revolution speed and rotation speed of the ball mill are used to obtain a mixture II with a median particle size of less than 0.1 μm.

According to some embodiments of the preparation method of the present invention, the high energy ball milling is a stirring ball milling, a vibration ball milling or a planetary ball milling, more preferably a planetary ball milling. The high-energy ball milling apparatus may be a high-energy ball mill, such as a stirred ball mill, a vibratory ball mill or a planetary ball mill, and more preferably a planetary ball mill.

According to some embodiments of the method of manufacturing of the present invention, the drying conditions comprise: the temperature is 110-150 ℃, preferably 110-130 ℃, and the time is 2-16h, preferably 3-12 h. The drying conditions are such as to evaporate the water present in the mixture II. In the present invention, the drying apparatus may be an oven as is conventional in the art.

According to some embodiments of the method of manufacturing of the present invention, the acid solution comprises a solute and a solvent. Further preferably, the solute in the acid solution is an organic acid and/or an inorganic acid; and/or the solvent in the acid solution is deionized water. Preferably, the solute concentration in the acid solution is 0.5-4 wt%. Such as 0.5 wt%, 1 wt%, 1.5 wt%, 1.8 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, and any value between any two of the foregoing.

According to some embodiments of the method of the present invention, the weight ratio of the acid solution to the dried product based on the solvent is (1-4): 5, preferably (2-4): 5. "acid solution in terms of solvent" means calculated on the solvent in the acid solution.

According to some embodiments of the preparation method of the present invention, the organic acid is one or more of acetic acid, oxalic acid, citric acid, and tartaric acid; more preferably, the inorganic acid is one or more of hydrochloric acid, sulfuric acid and nitric acid, more preferably nitric acid. For example, the acid solution is an aqueous nitric acid solution or an aqueous hydrochloric acid solution, and more preferably an aqueous nitric acid solution.

According to some embodiments of the method of manufacturing of the present invention, the method of forming is extrusion molding. The extrusion molding equipment can be a screw rod extruder conventional in the field.

According to some embodiments of the method of manufacturing of the present invention, the drying conditions include: the temperature is 110-150 ℃, preferably 110-130 ℃, and the time is 2-16h, preferably 3-12 h. In the present invention, the drying apparatus may be an oven as is conventional in the art.

According to some embodiments of the method of manufacturing of the present invention, the conditions of the firing include: the temperature is 500-900 ℃, preferably 550-800 ℃ and the time is 3-16h, preferably 4-12 h. In the present invention, the apparatus for calcination may be a muffle furnace, which is conventional in the art.

In a second aspect, the invention provides a titania-alumina composite carrier prepared by the above method.

The titanium oxide-aluminum oxide composite carrier prepared by the method of the invention, TiO in the carrier₂And Al₂O₃The distribution is uniform, and the carrier can be characterized by SEM-Mapping by using a scanning electron microscope. The specific characterization method can be as follows: and (3) coating the ground sample on a conductive adhesive, spraying gold on the surface of the conductive adhesive by using an ion sputtering instrument, drying, spraying carbon on the sample before characterization, and characterizing the sample by using a QUANTA 200 scanning electron microscope of FEI company. The characterization result can be shown in fig. 1a and 1b, and it can be seen from fig. 1a and 1b that the distribution of aluminum atoms and titanium atoms of the titania-alumina composite carrier prepared by the present invention is uniform (since the original image is a color image, it can be clearly seen that the uniform distribution is observed, and the display effect is affected after the arrangement is a black-and-white image).

In a third aspect, the present invention provides the use of the above titania-alumina composite support and/or the titania-alumina composite support prepared according to the above method in pyrolysis gasoline hydrogenation and DCC pyrolysis naphtha hydrogenation. The application in pyrolysis gasoline hydrogenation and DCC pyrolysis naphtha hydrogenation.

The term "DCC" as used herein refers to catalytic cracking. According to the present invention DCC cracked naphtha refers to cracked naphtha produced by catalytic cracking.

In an embodiment of the present invention, the hydrogenation catalyst is prepared by loading a first active component and a second active component on the above titanium oxide-alumina composite carrier, wherein the first active component is molybdenum oxide, and the second active component is cobalt oxide and nickel oxide. Preferably, the content of the first active component is 12-20 wt% and the content of the second active component is 1-15 wt% based on the total weight of the hydrogenation catalyst. Preferably, the content of cobalt oxide in the second active component is 0.5-14.5 wt%, and the content of nickel oxide in the second active component is 0.5-14.5 wt%And (4) percent of the total amount. The hydrogenation catalyst is applied to C of pyrolysis gasoline₆～C₈、C₉～C₁₀In the distillate hydrogenation process, the method has the characteristics of good low-temperature activity, high hydrogenation activity at high airspeed and good stability.

According to a specific embodiment of the present invention, the preparation method of the hydrogenation catalyst comprises: and (2) impregnating the compound containing the first active component and the compound containing the second active component in the titanium oxide-alumina composite carrier, drying and roasting to obtain the hydrogenation catalyst, wherein the first active component is molybdenum element, and the second active component is cobalt element and nickel element. Preferably, the compound comprising the first active component is ammonium molybdate. Preferably, the compound containing the second active component is nickel nitrate or cobalt nitrate. Preferably, the drying conditions include: the temperature is 110-150 ℃, preferably 110-130 ℃, and the time is 2-16h, preferably 3-12 h. Preferably, the conditions of the calcination include: the temperature is 500-900 ℃, preferably 550-800 ℃ and the time is 3-16h, preferably 4-12 h.

And performing SEM-Mapping on the prepared hydrogenation catalyst for characterization. The results of the characterization can be shown in fig. 2a, 2b, 2c, 2d and 2e, and it can be seen from the figure that the aluminum atoms, titanium atoms, molybdenum atoms, cobalt atoms and nickel atoms of the hydrogenation catalyst prepared by the present invention are uniformly distributed (since the original image is a color image, the uniform distribution can be clearly seen, and the display effect is affected after the arrangement as a black-and-white image).

According to a preferred embodiment of the present invention, the above hydrogenation catalyst is applied to C of pyrolysis gasoline₆～C₈、C₉～C₁₀In the distillate hydrogenation process. Before hydrogenation reaction, the hydrogenation catalyst needs to be sulfurized, and the sulfurization method can be a method conventional in the art, for example, at the reactor temperature of 280 ℃ and 350 ℃, the hydrogen-oil volume ratio is 100-^-1And vulcanizing for 10-24h, and reducing the temperature to room temperature after vulcanization.

Preferably, the above hydrogenation catalyst is applied to the cracked steamC of oil₆-C₈When fraction hydrogenation is carried out, the inlet temperature of the reactor is 220 ℃ and 280 ℃, and the volume space velocity is 2-4h^-1The hydrogen-oil volume ratio is 300-500:1, and the pressure is 2.5-3.5 Mp.

Preferably, the hydrogenation catalyst is applied to C of pyrolysis gasoline₉～C₁₀When fraction hydrogenation is carried out, the inlet temperature of the reactor is 220 ℃ and 300 ℃, and the volume space velocity is 1-2h^-1The volume ratio of hydrogen to oil is 400-800:1, and the pressure is 2.5-3.5 Mpa.

In another embodiment of the invention, the hydrogenation protective agent is obtained by loading molybdenum oxide and nickel oxide on the titanium oxide-alumina composite carrier. Preferably, the molybdenum oxide is present in an amount of 5 to 20 wt% and the nickel oxide is present in an amount of 4 to 15 wt%, based on the total weight of the hydrogenation protection agent. The hydrogenation protective agent is applied to the hydrogenation process of DCC cracked naphtha, and has the characteristics of good low-temperature activity, capability of reducing the inlet temperature of a reactor and improvement on the operation stability of the device.

According to a specific embodiment of the present invention, the preparation method of the hydrogenation protective agent comprises: and (3) impregnating the titanium oxide-alumina composite carrier with a molybdenum-containing compound and a nickel-containing compound, drying and roasting to obtain the hydrogenation protective agent. Preferably, the compound containing molybdenum element is ammonium molybdate. Preferably, the compound containing nickel element is nickel nitrate. Preferably, the drying conditions include: the temperature is 110-150 ℃, preferably 110-130 ℃, and the time is 2-16h, preferably 3-12 h. Preferably, the conditions of the calcination include: the temperature is 500-900 ℃, preferably 550-800 ℃ and the time is 3-16h, preferably 4-12 h.

And performing SEM-Mapping on the prepared hydrogenation protective agent for characterization. The characterization result shows that the aluminum atoms, the titanium atoms, the molybdenum atoms and the nickel atoms of the hydrogenation protective agent prepared by the invention are uniformly distributed.

According to a preferred embodiment of the present invention, the above-described hydrogenation catalyst is applied to a hydrogenation process of DCC cracked naphtha. Before the reaction, the hydrogenation protective agent needs to be vulcanized, and the vulcanization method can be a method conventional in the field, for example, a reaction at 280-350 DEG CAt the reactor temperature, the hydrogen-oil volume ratio is 100-200:1, a cyclohexane solution with the DMDS (dimethyl disulfide) content of 1-5 weight percent is used, and the volume space velocity is 1-2h^-1And vulcanizing for 10-24h, and reducing the temperature to room temperature after vulcanization.

Preferably, the conditions of the hydrogenation process of DCC cracked naphtha comprise: the inlet temperature of the reactor is 120-180 ℃, and the volume space velocity is 2-4h^-1The hydrogen-oil volume ratio is 300-500:1, and the pressure is 3.5-8 Mpa.

Compared with the existing hydrogenation catalyst and hydrogenation protective agent, the hydrogenation catalyst and hydrogenation protective agent prepared by the titanium oxide-aluminum oxide composite carrier provided by the invention have the advantages of good low-temperature activity, high hydrogenation activity at high space velocity and good stability in the fields of pyrolysis gasoline hydrogenation and DCC naphtha hydrogenation, and the titanium source of the invention is metatitanic acid with relatively low price, so that the problem that the titanium source is expensive in the prior art is solved.

Drawings

FIG. 1a is an SEM-Mapping chart of the distribution of aluminum atoms in a titania-alumina composite carrier provided in example 1 of the present invention;

FIG. 1b is an SEM-Mapping chart of the titanium atom distribution in the titanium oxide-alumina composite carrier provided in example 1 of the present invention;

FIG. 2a is an SEM-Mapping chart of the distribution of aluminum atoms in a hydrogenation catalyst provided in example 4 of the present invention;

FIG. 2b is an SEM-Mapping chart of the distribution of titanium atoms in the hydrogenation catalyst provided in example 4 of the present invention;

FIG. 2c is an SEM-Mapping chart of the distribution of cobalt atoms in the hydrogenation catalyst provided in example 4 of the present invention;

FIG. 2d is an SEM-Mapping chart of the distribution of molybdenum atoms in the hydrogenation catalyst provided in example 4 of the present invention;

FIG. 2e is an SEM-Mapping chart of the distribution of nickel atoms in the hydrogenation catalyst provided in example 4 of the present invention.

Detailed Description

In order that the present invention may be more readily understood, the following detailed description of the invention is given by way of example only, and is not intended to limit the scope of the invention.

The test method of the invention is as follows:

(1) method for measuring median particle size the laser light scattering method for determining the particle size distribution of the catalytic cracking catalyst was referred to standard NB/SH/T0951-2017.

(2) The SEM-Mapping characterization method comprises the following steps: and (3) coating the ground sample on a conductive adhesive, spraying gold on the surface of the conductive adhesive by using an ion sputtering instrument, drying, spraying carbon on the sample before characterization, and characterizing the sample by using a QUANTA 200 scanning electron microscope of FEI company.

[ example 1 ]

This example illustrates the preparation of a titania-alumina composite support.

Alumina (specific surface area 200 m)²Per g, pore volume of 1mL/g) and metatitanic acid are added into deionized water to be uniformly mixed, wherein the weight ratio of alumina to metatitanic acid is 5:1, and the weight ratio of the total weight of alumina and metatitanic acid to the solvent is 5: 4. After mixing well, a mixture I is obtained. Putting the mixture I into a high-energy planetary ball mill for planetary ball milling, wherein the revolution speed of the ball mill is 200r/min, the rotation speed of the ball mill is 500r/min, the high-energy ball mill is 8h, the mixture II with the median particle size of 0.087 mu m is obtained after ball milling, putting the mixture II into an oven for drying overnight at 120 ℃, putting the obtained dried product into a screw rod type extruding machine, adding a nitric acid aqueous solution (the solute is nitric acid, the solvent is deionized water, and the concentration of the solute is 2 wt%), wherein the weight ratio of the deionized water in the acid solution to the dried product is 3:5, extruding and molding, drying for 5h at 110 ℃, then putting into a muffle furnace for roasting for 6h at 550 ℃, and obtaining the titanium oxide-aluminum oxide composite carrier A.

SEM-Mapping characterization was performed on the titania-alumina composite carrier A, and the characterization results are shown in FIG. 1a and FIG. 1 b. It can be seen from FIGS. 1a and 1b that the titania-alumina composite carrier A prepared by the present invention has a uniform distribution of aluminum atoms and titanium atoms.

[ example 2 ]

This example illustrates the preparation of a titania-alumina composite support.

Alumina (specific surface area 150 m)²Per g, pore volume of 0.8mL/g) and metatitanic acid in a weight ratio of 6:1, and a solvent in a weight ratio of 1: 1. After mixing well, a mixture I is obtained. Putting the mixture I into a high-energy planetary ball mill for planetary ball milling, wherein the revolution speed of the ball mill is 300r/min, the rotation speed of the ball mill is 600r/min, the high-energy ball mill is 8h, the mixture II with the median particle size of 0.093 mu m is obtained after ball milling, putting the mixture II into an oven for drying overnight at 120 ℃, putting the obtained dried product into a screw rod type extruding machine, adding a nitric acid aqueous solution (the solute is nitric acid, the solvent is deionized water, and the concentration of the solute is 1.8 wt%), wherein the weight ratio of the deionized water in the acid solution to the dried product is 4:5, extruding and molding, drying for 3h at 130 ℃, and then putting into a muffle furnace for roasting for 4h at 800 ℃ to obtain the titanium oxide-aluminum oxide composite carrier B.

And performing SEM-Mapping characterization on the titanium oxide-alumina composite carrier B, wherein the characterization result is similar to that of the figure 1a and the figure 1B. The titanium oxide-aluminum oxide composite carrier B prepared by the invention has uniform distribution of aluminum atoms and titanium atoms.

[ example 3 ]

This example illustrates the preparation of a titania-alumina composite support.

Alumina (specific surface area 300 m)²Per g, pore volume of 1.2mL/g) and metatitanic acid were added to deionized water and mixed uniformly, wherein the weight ratio of alumina to metatitanic acid was 7:1, and the weight ratio of the total weight of alumina and metatitanic acid to the solvent was 5: 3. After mixing well, a mixture I is obtained. Placing the mixture I into a high-energy planetary ball mill for planetary ball milling, wherein the revolution rotating speed of the ball mill is 300r/min, the rotation rotating speed of the ball mill is 300r/min, the high-energy ball mill is 10h, obtaining a mixture II with the median particle size of 0.082 mu m after ball milling, placing the mixture II into an oven for drying overnight at 120 ℃, placing the obtained dried product into a screw rod type extruding machine, adding a hydrochloric acid aqueous solution (the solute is hydrochloric acid, the solvent is deionized water, and the concentration of the solute is 2.5 wt%), wherein the weight ratio of the deionized water in the acid solution to the dried product isAnd 2:5, extruding and molding, drying for 3h at 150 ℃, and then roasting for 12h at 550 ℃ in a muffle furnace to obtain the titanium oxide-aluminum oxide composite carrier C.

The titanium oxide-alumina composite carrier C is subjected to SEM-Mapping characterization, and the characterization results are similar to those of FIG. 1a and FIG. 1 b. The titanium oxide-aluminum oxide composite carrier C prepared by the invention has uniform distribution of aluminum atoms and titanium atoms.

[ example 4 ]

This example illustrates the preparation of a hydrogenation catalyst.

Preparing an ammonium molybdate tetrahydrate aqueous solution with the concentration of 26.68g/100mL (26.68 g of ammonium molybdate tetrahydrate is contained in 100mL of deionized water), adding 5mL of ammonia water with the concentration of 14 weight percent to fully dissolve the ammonium molybdate tetrahydrate, taking 100g of the titanium oxide-alumina composite carrier A prepared in the example 1, impregnating for 2h at normal temperature, filtering, drying for 4h at the temperature of 110 ℃, and roasting for 4h at the temperature of 550 ℃ to obtain a precursor. Then the precursor is impregnated with an aqueous solution of nickel nitrate hexahydrate with a concentration of 23.48g/100mL and cobalt nitrate hexahydrate with a concentration of 11.62g/100mL (23.48 g and 11.62g of nickel nitrate hexahydrate per 100mL of deionized water), impregnated at normal temperature for 2h, filtered, dried at 110 ℃ for 4h, and calcined at 550 ℃ for 4h to obtain MoO₃Hydrogenation catalyst A (MoO) having a content of 15 wt.%, a CoO content of 2.0 wt.% and a NiO content of 4.0 wt.%₃-CoO-NiO/Al₂O₃-TiO₂)。

The hydrogenation catalyst A was subjected to SEM-Mapping characterization, and the results are shown in FIG. 2a, FIG. 2b, FIG. 2c, FIG. 2d and FIG. 2 e. It can be seen from the figure that the hydrogenation catalyst A prepared by the present invention has uniform distribution of aluminum atoms, titanium atoms, molybdenum atoms, cobalt atoms and nickel atoms.

[ example 5 ]

This example illustrates the preparation of a hydrogenation catalyst.

Preparing an ammonium molybdate tetrahydrate aqueous solution with the concentration of 26.68g/100mL, then adding 5mL of ammonia water with the concentration of 14 weight percent to fully dissolve the ammonium molybdate tetrahydrate, taking 100g of the titanium oxide-alumina composite carrier B prepared in the example 2, dipping for 2h at normal temperature, filtering, drying for 4h at 110 ℃, and roasting for 4h at 550 ℃ to obtain a precursor.Then impregnating the precursor with an aqueous solution of nickel nitrate hexahydrate and cobalt nitrate hexahydrate with the concentration of 17.61g/100mL, impregnating at normal temperature for 2h, filtering, drying at 110 ℃ for 4h, and roasting at 550 ℃ for 4h to obtain MoO₃Hydrogenation catalyst B (MoO) having a content of 15 wt.%, a CoO content of 3.5 wt.% and a NiO content of 3.0 wt.%₃-CoO-NiO/Al₂O₃-TiO₂)。

SEM-Mapping characterization was performed on hydrogenation catalyst B, and the characterization results were similar to those in FIG. 2a, FIG. 2B, FIG. 2c, FIG. 2d and FIG. 2 e. It can be seen from the figure that the hydrogenation catalyst B prepared by the present invention has a uniform distribution of aluminum atoms, titanium atoms, molybdenum atoms, cobalt atoms and nickel atoms.

[ example 6 ]

This example illustrates the preparation of a hydroprotectant.

Preparing an ammonium molybdate tetrahydrate aqueous solution with the concentration of 15.62g/100mL, then adding 5mL of ammonia water with the concentration of 14 weight percent to fully dissolve the ammonium molybdate tetrahydrate, taking 100g of the titanium oxide-alumina composite carrier C prepared in the example 3, dipping for 2h at normal temperature, filtering, drying for 4h at 110 ℃, and roasting for 4h at 550 ℃ to obtain a precursor. Then impregnating the precursor with aqueous solution of nickel nitrate hexahydrate with the concentration of 55.272g/100mL, impregnating at normal temperature for 2h, filtering, drying at 110 ℃ for 4h, and roasting at 550 ℃ for 4h to obtain MoO₃A hydrogenation protective agent C (MoO) with a content of 8.5 wt% and a NiO content of 10.5 wt%₃-NiO/Al₂O₃-TiO₂)。

SEM-Mapping characterization was performed on the hydro-protectant C, and the characterization results were similar to those in FIG. 2a, FIG. 2b, FIG. 2d and FIG. 2 e. It can be seen from the figure that the hydrogenation catalyst C prepared by the present invention has uniform distribution of aluminum atoms, titanium atoms, molybdenum atoms and nickel atoms.

[ example 7 ]

A titania-alumina composite carrier was prepared by the method of example 1, except that the specific surface area was set to 200m²The alumina with the pore volume of 1mL/g is replaced by the alumina with the specific surface area of 370m²Alumina with a pore volume of 0.53 mL/g. And a hydrogenation catalyst was prepared as in example 4 and designated hydrogenation catalyst D.

[ example 8 ]

A titania-alumina composite carrier was prepared by the method of example 1, except that the specific surface area was set to 200m²The alumina with the pore volume of 1mL/g is replaced by the alumina with the specific surface area of 350m²Alumina with a pore volume of 1.5 mL/g. And a hydrogenation catalyst was prepared as in example 4 and designated hydrogenation catalyst E.

[ example 9 ]

A titania-alumina composite carrier was prepared according to the method of example 1, except that the weight ratio of alumina to metatitanic acid was 15: 1. and a hydrogenation catalyst was prepared as in example 4 and is designated hydrogenation catalyst F.

[ example 10 ]

A titania-alumina composite carrier was prepared according to the method of example 1, except that the weight ratio of alumina to metatitanic acid was 3: 1. and a hydrogenation catalyst was prepared as in example 4 and designated hydrogenation catalyst G.

Comparative example 1

Alumina (specific surface area 200 m)²Per g, pore volume of 1mL/g) and metatitanic acid are added into deionized water to be uniformly mixed, wherein the weight ratio of alumina to metatitanic acid is 5:1, and the weight ratio of the total weight of alumina and metatitanic acid to the solvent is 5: 4. And (4) uniformly mixing to obtain a mixture. And putting the mixture into an oven for drying at 120 ℃ overnight, putting the obtained dried product into a screw rod type extruding machine, adding a nitric acid aqueous solution (the solute is nitric acid, the solvent is deionized water, and the concentration of the solute is 2 wt%), wherein the weight ratio of the deionized water in the acid solution to the dried product is 3:5, extruding and molding, drying at 110 ℃ for 5 hours, and then putting into a muffle furnace for roasting at 550 ℃ for 6 hours to obtain the composite carrier D-1.

Preparing ammonium molybdate tetrahydrate aqueous solution with the concentration of 26.68g/100mL, then adding 5mL of ammonia water with the concentration of 14 weight percent to fully dissolve the ammonium molybdate tetrahydrate, taking 100g of the composite carrier D-1, soaking at normal temperature for 2h, filtering, drying at 110 ℃ for 4h, and roasting at 550 ℃ for 4h to obtain the precursor. The precursor was then treated with nickel nitrate hexahydrate at a concentration of 23.48g/100mL and nitric acid hexahydrate at a concentration of 11.62g/100mLSoaking in cobalt water solution at room temperature for 2 hr, filtering, drying at 110 deg.C for 4 hr, and calcining at 550 deg.C for 4 hr to obtain MoO₃Hydrogenation catalyst DC-1 (MoO) having a content of 15 wt.%, a CoO content of 2.0 wt.% and a NiO content of 4.0 wt.%₃-CoO-NiO/Al₂O₃-TiO₂)。

Comparative example 2

A titania-alumina composite carrier D-2 was prepared according to the method of example 1 of CN 1184289C. The specific operation is as follows:

taking the specific surface area of 160 meters²90 g of cloverleaf alumina with pore volume of 0.58 ml/g and most probable pore diameter of 130 angstrom is soaked in 53ml of dilute sulfuric acid solution of 0.557 g/ml of titanium sulfate, stirred for 15 min, dried at 120 ℃ for 8h and then roasted at 900 ℃ for 4h to obtain the compound D-2. The resulting composite had a titanium oxide content of 10% by weight and a specific surface area of 144 m²A pore volume of 0.56 ml/g, and a pore diameter of 125 angstroms.

Preparing ammonium molybdate tetrahydrate aqueous solution with the concentration of 26.68g/100mL, then adding 5mL of ammonia water with the concentration of 14 weight percent to fully dissolve the ammonium molybdate tetrahydrate, taking 100g of the composite carrier D-2, soaking at normal temperature for 2h, filtering, drying at 110 ℃ for 4h, and roasting at 550 ℃ for 4h to obtain the precursor. Then impregnating the precursor with an aqueous solution of nickel nitrate hexahydrate and cobalt nitrate hexahydrate with the concentration of 17.61g/100mL, impregnating at normal temperature for 2h, filtering, drying at 110 ℃ for 4h, and roasting at 550 ℃ for 4h to obtain MoO₃Hydrogenation catalyst DC-2 (MoO) having a content of 15 wt.%, a CoO content of 3.5 wt.% and a NiO content of 3.0 wt.%₃-CoO-NiO/Al₂O₃-TiO₂)。

Comparative example 3

Alumina (specific surface area 200 m)²Per g, pore volume of 1mL/g) and metatitanic acid are added into deionized water to be uniformly mixed, wherein the weight ratio of alumina to metatitanic acid is 5:1, and the weight ratio of the total weight of alumina and metatitanic acid to the solvent is 5: 4. And (4) uniformly mixing to obtain a mixture. Drying the mixture in an oven at 120 deg.C overnight, putting the dried product into a screw rod type extruding machine, and adding nitric acid waterAnd (2) extruding the solution (the solute is nitric acid, the solvent is deionized water, and the concentration of the solute is 2 wt%) at a weight ratio of 3:5, drying at 110 ℃ for 5h, and roasting in a muffle furnace at 550 ℃ for 6h to obtain the composite carrier D-3.

Preparing ammonium molybdate tetrahydrate aqueous solution with the concentration of 26.68g/100mL, then adding 5mL of ammonia water with the concentration of 14 weight percent to fully dissolve the ammonium molybdate tetrahydrate, taking 100g of the composite carrier D-3, soaking at normal temperature for 2h, filtering, drying at 110 ℃ for 4h, and roasting at 550 ℃ for 4h to obtain the precursor. Then impregnating the precursor with aqueous solution of nickel nitrate hexahydrate with the concentration of 55.272g/100mL, impregnating at normal temperature for 2h, filtering, drying at 110 ℃ for 4h, and roasting at 550 ℃ for 4h to obtain MoO₃The hydrogenation protective agent DC-3 with the content of 8.5 weight percent and the NiO content of 10.5 weight percent.

Comparative example 4

The procedure is as in example 1, except that, after ball milling, a mixture II having a median particle diameter of 0.15 μm is obtained. A hydrogenation catalyst, designated hydrogenation catalyst DC-4, was prepared according to the procedure of example 4.

[ test example 1 ]

Benzene production apparatus C using China petrochemical Yanshan petrochemical olefin part₆～C₈The first-stage hydrogenation product of the fraction is used as a hydrofining raw material, the total sulfur content of the raw material is 98ppm, and the bromine number is 19.09 (gBr)₂Per 100g of oil). The hydrogenation catalyst A, B, D, E, F, G and the hydrogenation catalysts DC-1, DC-2 and DC-4 (all having a loading of 100mL) were evaluated in comparison. The evaluation conditions and product analysis are shown in Table 1.

TABLE 1

[ test example 2 ]

Benzene production apparatus C using China petrochemical Yanshan petrochemical olefin part₆～C₈The first-stage hydrogenation product of the fraction is used as a hydrofining raw material, the total sulfur content of the raw material is 98ppm, and the bromine number is 19.09 (gBr)₂Per 100g of oil). The comparative evaluation was carried out on the hydrogenation catalyst B and the hydrogenation catalyst DC-2 (both having a loading of 100 mL). The evaluation conditions and product analysis are shown in Table 2.

TABLE 2

[ test example 3 ]

Chemical engineering plant C from Tianli high New company of Dushan mountain in Xinjiang₉～C₁₀Fraction two-stage hydrogenation raw material with total sulfur content of 400ppm and bromine number of 29 (gBr)₂Per 100g of oil). The hydrogenation catalyst A, B, D, E, F, G and the hydrogenation catalysts DC-1, DC-2 and DC-4 (all having a loading of 100mL) were evaluated for comparison. The results of the product analysis are shown in Table 3.

TABLE 3

[ test example 4 ]

DCC naphtha hydrogenation raw material of certain chemical plant in Shaanxi is used as raw material, and the diene content of the raw material is 10.5 (gI)₂Per 100g of oil) bromine number of 31 (gBr)₂Per 100g of oil). Comparative evaluation was carried out on the hydrogenation protective agent C and the hydrogenation protective agent DC-3 (both having a loading of 100 mL). The evaluation conditions and product analysis are shown in Table 4.

TABLE 4

[ test example 5 ]

DCC naphtha hydrogenation raw material of certain chemical plant in Shaanxi is used as raw material, and the diene content of the raw material is 10.5 (gI)₂Per 100g of oil) bromine number of 31 (gBr)₂Per 100g of oil). 100mL fixed bed reactors are used for series connection, a first-stage reactor is filled with 100mL hydrogenation catalyst B, a first-stage hydrogenation product is used as a raw material at the inlet of a second-stage reactor, and the second-stage reactor is filled with 100mL hydrogenation protective agent C. The results of the evaluation of the hydrogenated product are shown in Table 5.

TABLE 5

As can be seen from FIGS. 1a and 1b, the titanium oxide-alumina composite carrier prepared by the method of the present invention has a uniform distribution of aluminum atoms and titanium atoms, i.e., TiO₂The distribution is uniform. And as can be seen from fig. 2a, 2b, 2c, 2d and 2e, the hydrogenation catalyst prepared using the titania-alumina composite carrier of the present invention has a uniform distribution of aluminum atoms, titanium atoms, molybdenum atoms, cobalt atoms and nickel atoms.

In addition, it can be seen from test examples 1 to 5 and tables 1 to 5 that the hydrogenation catalyst and the hydrogenation protective agent prepared by using the titanium oxide-alumina composite carrier of the present invention have higher low temperature activity and hydrogenation activity and stability at high space velocity in the fields of pyrolysis gasoline hydrogenation and DCC naphtha hydrogenation, and are suitable for large-scale industrial production due to the use of metatitanic acid as a titanium source, and the preparation cost is low.

It should be noted that the above-mentioned embodiments are only for explaining the present invention, and do not constitute any limitation to the present invention. The present invention has been described with reference to exemplary embodiments, but the words which have been used herein are words of description and illustration, rather than words of limitation. The invention can be modified, as prescribed, within the scope of the claims and without departing from the scope and spirit of the invention. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein, but rather extends to all other methods and applications having the same functionality.