阅读说明：本技术 一种馏分油加氢催化剂及其制备方法 (Distillate oil hydrogenation catalyst and preparation method thereof ) 是由 段为宇 姚运海 刘丽 杨成敏 郭蓉 周勇 丁莉 孙进 郑步梅 于 2019-10-25 设计创作，主要内容包括：本发明公开了一种馏分油加氢催化剂及其制备方法。本发明的馏分油加氢催化剂包括加氢活性金属和氧化铝载体,所述的加氢活性金属为第VIB族金属和第VIII族金属,第VIB族金属为Mo和/或W,第VIII族金属为Ni和/或Co,以催化剂总重量计,MoS-2和/或WS-2为6%～30%,Co-9S-8和/或Ni-3S-2为4%～10%,MoO-3和/或WO-3为3%～15%。制备方法如下：(1)用浸渍液I浸渍氧化铝载体,经干燥后进行硫化处理；其中浸渍液I中含有第VIB族金属、第VIII族金属和有机化合物I；(2)用浸渍液II浸渍硫化物料,经干燥后,制备出硫化物-氧化物复合型催化剂；浸渍液II含有第VIB族金属和有机化合物。本发明催化剂活性金属分散性好,具有较高的硫化度和II类活性中心数,催化剂活性高,适用于馏分油的加氢脱硫反应。(The invention discloses a distillate oil hydrogenation catalyst and a preparation method thereof. The distillate oil hydrogenation catalyst comprises hydrogenation active metals and an alumina carrier, wherein the hydrogenation active metals are VIB group metals and VIII group metals, the VIB group metals are Mo and/or W, the VIII group metals are Ni and/or Co, and MoS is calculated by the total weight of the catalyst 2 And/or WS 2 6 to 30 percent of Co 9 S 8 And/or Ni 3 S 2 4 to 10 percent of MoO 3 And/or WO 3 3% -15%. The preparation method comprises the following steps: (1) impregnating alumina carrier with impregnating solution I, dryingThen carrying out vulcanization treatment; wherein the impregnation liquid I contains VIB group metals, VIII group metals and organic compounds I; (2) impregnating the vulcanized material with the impregnation liquid II, and drying to prepare a sulfide-oxide composite catalyst; the impregnation liquid II contains VIB group metals and organic compounds. The catalyst has the advantages of good active metal dispersibility, higher vulcanization degree and II-type active center number, high activity and suitability for the hydrodesulfurization reaction of distillate oil.)

1. A distillate oil hydrogenation catalyst comprises hydrogenation active metal and an alumina carrier, and is characterized in that: the hydrogenation active metals are VIB group metals and VIII group metals, the VIB group metals are Mo and/or W, the VIII group metals are Ni and/or Co, and MoS is calculated by the total weight of the catalyst₂And/or WS₂6 to 30 percent of Co₉S₈And/or Ni₃S₂4 to 10 percent of MoO₃And/or WO₃3% -15%.

2. The catalyst of claim 1, wherein: MoS based on the total weight of the catalyst₂And/or WS₂10 to 20 weight percent of Co₉S₈And/or Ni₃S₂5% -8% of MoO₃And/or WO₃5wt% to 10 wt%.

3. The catalyst of claim 1, wherein: the pore volume of the distillate oil hydrogenation catalyst is 0.3-1.3 mL/g, and the specific surface area is 150-400 m²/g。

4. A method for preparing a distillate oil hydrogenation catalyst according to any one of claims 1 to 3, characterized by comprising the following steps: (1) impregnating an alumina carrier with the impregnating solution I, drying the impregnated carrier, and then vulcanizing; wherein the impregnation liquid I contains VIB group metals, VIII group metals and organic compounds I; (2) impregnating the vulcanized material obtained in the step (1) with an impregnating solution II, and drying to prepare a distillate oil hydrogenation catalyst; the impregnation liquid II contains VIB group metals and organic compounds; the organic compound in the step (1) and the step (2) is one or more of organic acid, organic alcohol and sugar.

5. The method of claim 4, wherein: the alumina carrier contains one or more auxiliary agents of silicon, titanium, magnesium, boron or zirconium, and the content of the auxiliary agent is 0.1-10% of the weight of the alumina carrier by element.

6. The method of claim 4, wherein: the VIB group metal is Mo and/or W, and the VIII group metal is Ni and/or Co.

7. The method of claim 4, wherein: the drying temperature after each dipping is 80-200 ℃, and the drying time is 3-24 hours.

8. The method of claim 4, wherein: the vulcanization treatment in the step (1) adopts an in-situ or ex-situ vulcanization process, the amount of the introduced vulcanizing agent is 90-150% of the theoretical sulfur demand of the catalyst, and the vulcanization process adopts temperature programming, wherein the temperature is raised to 200-350 ℃ and is kept constant for 1-16 h.

9. The method of claim 8, wherein: the vulcanizing agent is one or more of carbon disulfide, dimethyl disulfide, methyl sulfide or n-butyl sulfide.

10. The method of claim 4, wherein: the organic acid is at least one selected from dibasic acids with the carbon number of 2-10; the organic alcohol is selected from one or more of aliphatic alcohol with 3-10 carbon atoms and dihydric alcohol; the saccharide is selected from one or more of monosaccharide, disaccharide and polysaccharide with the carbon number of 3-10.

11. Use of the distillate oil hydrogenation catalyst of any one of claims 1 to 3 in a hydrodesulfurization process of a liquefied gas, gasoline, kerosene, diesel oil or wax oil fraction.

12. A distillate oil hydrogenation catalyst according to any one of claims 1 to 3, characterized in that: after the distillate oil hydrogenation catalyst is vulcanized, the average length of the active phase is 4-7 nm, the average number of the platelets in a single stacked layer is 1-5, and the proportion of stacked layers with 3-5 layers is 40-90% based on the total number of the stacked layers.

Technical Field

The invention relates to a distillate oil hydrogenation catalyst and a preparation method thereof.

Background

The environment protection, green, low carbon and environmental protection are always the subject of continuous pursuit of human beings, and developed countries and regions such as Europe are always earlier than China in the establishment of diesel oil standards. In the last 5 years in China, the upgrading pace of diesel oil quality is accelerated, the upgrading from the national IV diesel oil standard to the national VI standard is completed in a shorter time, the diesel oil quality standard is equivalent to the advanced indexes in the world such as Europe, and the pollution of diesel oil fuel to the environment is effectively reduced. The high-quality clean fuel standard accelerates the development of diesel hydrogenation catalysts of various petroleum companies in the world, and in recent years, Mo-Co and Mo-Ni series high-activity diesel ultra-deep hydrogenation desulfurization catalysts with continuous technological progress are developed by respectively adopting different technologies.

The diesel oil deep desulfurization catalysts developed by various companies represented by Albemarle, Criterion, Tops Brother and Axens abroad are all II-class active center catalysts. The class II active site catalyst is characterized by MoS₂With weaker interaction with the alumina support, using improved support and impregnationThe preparation method has the core that an organic complexing agent is introduced to weaken the interaction between the active metal and the carrier, improve the dispersion degree of the active metal on the carrier and promote the formation of the II-type active center catalyst.

CN201610767708.9 describes a preparation method of a hydrogenation catalyst. In the method, part of active metal components and organic acid complexing agents are introduced in the carrier forming process, the carrier is formed through a certain roasting treatment procedure, and then the subsequent active metal impregnation step is carried out to obtain the second-class active center catalyst.

The second class of active center catalysts generally adopt a special starting method to achieve a good activity effect. CN201010222027.7 discloses a start-up sulfuration method of a second-class active center hydrogenation catalyst. The method introduces the vulcanizing oil with a lower wetting temperature than the conventional vulcanizing temperature. The start-up vulcanization method of the catalyst requires the temperature to be less than 120 ℃, so that the catalyst is favorable for forming more second-class hydrogenation active centers, and the service performance of the catalyst is improved.

The above patents have a certain promotion effect on increasing the number of the second-class active centers of the catalyst in both the preparation method and the vulcanization process by adopting a special start-up method, but still cannot maximize the number of the second-class active centers of the catalyst, and further improvement is needed.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a distillate oil hydrogenation catalyst and a preparation method thereof. The catalyst prepared by the method has good active metal dispersibility, higher vulcanization degree and II-type active center number, high activity and suitability for the hydrodesulfurization reaction of distillate oil.

The distillate oil hydrogenation catalyst comprises hydrogenation active metals and an alumina carrier, wherein the hydrogenation active metals are VIB group metals and VIII group metals, the VIB group metals are Mo and/or W, the VIII group metals are Ni and/or Co, and MoS is calculated by the total weight of the catalyst₂And/or WS₂6 to 30 percent, preferably 10 to 20 percent by weight of Co₉S₈And/or Ni₃S₂4 to 10 percent, preferably 5 to 8 percent of MoO₃And/or WO₃3 to 15 percent, preferably 5 to 10 percent by weight.

The distillate oil hydrogenation catalyst has the pore volume of 0.3-1.3 mL/g and the specific surface area of 150-400 m²/g。

The preparation method of the distillate oil hydrogenation catalyst comprises the following steps of (1) impregnating an alumina carrier with an impregnating solution I, drying the impregnated carrier, and then vulcanizing; wherein the impregnation liquid I contains VIB group metals, VIII group metals and organic compounds I; (2) impregnating the vulcanized material obtained in the step (1) with an impregnating solution II, and drying to prepare a distillate oil hydrogenation catalyst; the impregnation liquid II contains VIB group metals and organic compounds; the organic compound in the step (1) and the step (2) is one or more of organic acid, organic alcohol and sugar.

In the method, the alumina carrier can be prepared by a conventional method, the alumina carrier can contain a small amount of auxiliary agent such as one or more of silicon, titanium, magnesium, boron and zirconium, and the content of the auxiliary agent is 0.1-10% of the weight of the alumina carrier by element. The properties of the alumina support are generally required as follows: the pore volume is 0.3-1.5 ml/g, the specific surface area is 150-450 m²/g。

In the method, the VIB group metal is Mo and/or W, and the VIII group metal is Ni and/or Co. The preparation of the impregnation solution in the process of the invention is well known to the person skilled in the art and generally a water-soluble compound containing the metal element is used as source, the concentration of the impregnation solution and the amount added being determined according to the composition of the catalyst.

In the method, the drying temperature is 80-200 ℃ after each dipping, and the drying time is 3-24 hours.

In the method, the vulcanizing treatment in the step (1) adopts an in-situ or ex-situ vulcanizing process, the amount of the introduced vulcanizing agent is 90-150% of the theoretical sulfur demand of the catalyst, and the vulcanizing process adopts temperature programming, wherein the temperature is raised to 200-350 ℃ and is kept for 1-16 hours. The vulcanizing agent is typically one or more of carbon disulfide, dimethyl disulfide, methyl sulfide, n-butyl sulfide.

In the method, the organic acid is at least one selected from dibasic acids with 2-10 carbon atoms; the organic acid is one or more of citric acid, citric anhydride, isocitric acid, malic acid, tartaric acid, oxalic acid, succinic acid, glutaric acid, adipic acid, benzoic acid, phthalic acid, isophthalic acid, salicylic acid or malonic acid; the organic alcohol is selected from one or more of aliphatic alcohol with 3-10 carbon atoms and dihydric alcohol; the organic alcohol is one or more of fatty alcohol, ethylene glycol, propylene glycol, glycerol, trimethylene ethane, trimethylene propane, diethylene glycol, dipropylene glycol, trimethylene glycol, triethylene glycol, tributylene glycol, tetraethylene glycol, tetrapropylene glycol, polyethylene glycol, diethylene methyl glycol, diethylene ethyl glycol, diethylene allyl glycol and diethylene butyl glycol; the saccharide is at least one selected from monosaccharide, disaccharide and polysaccharide with the carbon number of 3-10.

The distillate oil hydrogenation catalyst is suitable for the hydrogenation and desulfurization process of fractions such as liquefied gas, gasoline, kerosene, diesel oil, wax oil and the like, and is particularly suitable for the hydrogenation and desulfurization process of diesel oil.

After the distillate oil hydrogenation catalyst is vulcanized, the active phase (in MoS)₂For example) has an average length of 4-7 nm, the average number of the platelets in a single stacked layer is 1-5, and the ratio of stacked layers with 3-5 layers is 40-90%, preferably 40-70%, based on the total number of stacked layers.

Because the VIB group metal is harder to vulcanize than the VIII group metal, the phenomenon that the vulcanized VIII group metal is wrapped by the vulcanized VIB group metal is easy to cause, the sulfide-oxide composite catalyst of the invention adopts a method of dipping the VIB group metal on the vulcanized VIB group metal and the VIII group metal, and the vulcanization operation is carried out after the VIB group metal and the VIII group metal are partially dipped firstly, so that the phenomenon that the vulcanized VIII group metal is wrapped by the vulcanized VIB group metal can be avoided, and stronger adsorption sites on the surface of a carrier can be covered, the interaction force between the subsequent dipped active metal and the surface of the carrier is weakened, the subsequent VIB group active metal can be better dispersed, and the full play can be realizedThe group metal auxiliary agent promotes the generation of II active centers, thereby improving the activity of the catalyst.

Drawings

FIG. 1 is a transmission electron micrograph of a catalyst of example 1 of the present invention.

FIG. 2 is a transmission electron micrograph of a comparative example 1 catalyst.

Detailed Description

In the present invention, the specific surface area and the pore volume are measured by a low-temperature liquid nitrogen adsorption method. The length of the lamella and the layer number ratio of the stacking layers are measured by a field emission transmission electron microscope, and the specific method comprises the following steps: selecting more than 350 MoS₂Counting and arranging the average layer number, the average length and the proportion of 3-5 layers of wafers by using the platelets, wherein the statistical formula is as follows:

and

wherein l_iRepresenting the wafer length, N_iRepresents the number of i layers, a_iRepresentative wafer l_iNumber of (a), (b)_iNumber of representative layers N_iThe number of (2). In the present invention, wt% means mass percentage.

Example 1

100g of alumina carrier (water absorption rate of 80mL/100 g) is placed in a rolling pot, under the condition of rotation, 80mL of aqueous solution containing 20.2g of molybdenum trioxide, 14.5g of basic cobalt carbonate, 0.2g of ethylene glycol and 2.0g of citric acid is sprayed into the alumina carrier in the rolling pot in an atomizing mode, after the solution is sprayed, the rolling pot is rotated for 30 minutes, and the drying is carried out for 4 hours at 110 ℃, so as to prepare the first-stage oxidation state catalyst A. And (3) carrying out vulcanization treatment on the first-stage oxidation state catalyst A by adopting an in-situ vulcanization process, introducing dimethyl disulfide accounting for 120% of the theoretical sulfur demand of the catalyst, and carrying out temperature programming in the vulcanization process, wherein the temperature is raised to 320 ℃ and is kept constant for 10 hours, so as to obtain the first-stage vulcanization catalyst A. Putting a section of the sulfidation catalyst A into a rolling pot, spraying 40mL of aqueous solution containing 8.8g of molybdenum trioxide, 0.1g of ethylene glycol and 0.3g of citric acid into an alumina carrier in the rolling pot in an atomization mode under the rotating condition, continuously rotating the rolling pot for 30 minutes after the solution is sprayed, and drying the rolling pot for 4 hours at the temperature of 110 ℃ to obtain the finished sulfide-oxide composite catalyst A.

Example 2

100g of alumina carrier (water absorption rate of 80mL/100 g) is placed in a rolling pot, under the condition of rotation, 80mL of aqueous solution containing 21.3g of molybdenum trioxide, 17.9g of basic cobalt carbonate, 0.4g of ethylene glycol and 1.6g of citric acid is sprayed into the alumina carrier in the rolling pot in an atomizing mode, after the solution is sprayed, the rolling pot is rotated for 30 minutes, and the drying is carried out for 4 hours at 110 ℃, so as to prepare the first-stage oxidation state catalyst B. And (3) carrying out vulcanization treatment on the first-stage oxidation state catalyst B by adopting an in-situ vulcanization process, introducing 120% of the theoretical sulfur demand of the catalyst by using the amount of dimethyl disulfide, and carrying out temperature programming in the vulcanization process, wherein the temperature is raised to 320 ℃ and is kept for 10 hours to obtain the first-stage vulcanization catalyst B. Putting a section of the sulfidation catalyst A into a rolling pot, spraying 38mL of aqueous solution containing 9.0g of molybdenum trioxide, 0.2g of ethylene glycol and 0.4g of citric acid into the alumina carrier in the rolling pot in an atomization mode under the rotating condition, rotating the rolling pot for 30 minutes after the solution is sprayed, and drying the rolling pot for 4 hours at the temperature of 110 ℃ to obtain a finished product sulfide-oxide composite catalyst B.

Example 3

100g of alumina carrier (water absorption rate of 80mL/100 g) is placed in a rolling pot, under the condition of rotation, 80mL of aqueous solution containing 14.5g of basic cobalt carbonate, 18.0g of molybdenum trioxide, 1.0g of glycerol and 0.2g of oxalic acid is sprayed into the alumina carrier in the rolling pot in an atomization mode, after the solution is sprayed, the rolling pot is rotated for 30 minutes, and the primary oxidation state catalyst C is prepared after drying at 110 ℃ for 4 hours. And (3) carrying out vulcanization treatment on the first-stage oxidation state catalyst C by adopting an in-situ vulcanization process, introducing dimethyl disulfide accounting for 120% of the theoretical sulfur demand of the catalyst, and carrying out temperature programming in the vulcanization process, wherein the temperature is raised to 320 ℃ and is kept constant for 10 hours, so as to obtain the first-stage vulcanization catalyst C. And (2) placing a section of the sulfidation catalyst C in a rolling pot, spraying 42mL of aqueous solution containing 11.0g of molybdenum trioxide, 0.5g of glycerol and 0.3g of oxalic acid into the alumina carrier in the rolling pot in an atomization mode under the rotation condition, continuing to rotate in the rolling pot for 30 minutes after the solution is sprayed, and drying at 110 ℃ for 4 hours to obtain the finished sulfide-oxide composite catalyst C.

Example 4

100g of alumina carrier (water absorption rate of 80mL/100 g) is placed in a rolling pot, under the condition of rotation, 80mL of aqueous solution containing 19.3g of basic nickel carbonate, 3.5g of molybdenum trioxide, 24.3g of ammonium metatungstate, 0.2g of ethylene glycol and 1.8g of citric acid is sprayed into the alumina carrier in the rolling pot in an atomization mode, after the solution is sprayed, the rolling pot is rotated for 30 minutes continuously, and drying is carried out for 4 hours at 110 ℃ to prepare the first-stage oxidation state catalyst D. And (3) carrying out vulcanization treatment on the first-stage oxidation state catalyst D by adopting an in-situ vulcanization process, introducing dimethyl disulfide accounting for 120% of the theoretical sulfur demand of the catalyst, and carrying out temperature programming in the vulcanization process, wherein the temperature is raised to 320 ℃ and is kept constant for 10 hours, so as to obtain the first-stage vulcanization catalyst D. Putting a section of the sulfidation catalyst D into a rolling pot, spraying 39mL of an aqueous solution containing 2.9g of molybdenum trioxide, 7.1g of ammonium metatungstate, 0.1g of ethylene glycol and 0.7g of citric acid into an alumina carrier in the rolling pot in an atomization mode under the rotation condition, continuing rotating the rolling pot for 30 minutes after the solution is sprayed, and drying the rolling pot for 4 hours at the temperature of 110 ℃ to obtain a finished product of the sulfide-oxide composite catalyst D.

Example 5

On a 200mL small-sized hydrogenation device of a fixed bed, A, B, C, D catalysts are respectively adopted, the hydrogen partial pressure is 6.4MPa, and the liquid hourly space velocity is 1.5h^-1The volume ratio of hydrogen to oil is 500Nm³/m³And the average reaction temperature is 360 ℃, and the raw materials in the table 1 are hydrotreated.

TABLE 1 Properties of the raw materials

Comparative example 1

Preparing 80mL of aqueous solution containing 29.0g of molybdenum trioxide, 14.5g of basic cobalt carbonate, 0.3g of ethylene glycol and 2.3g of citric acid, putting 100g of alumina carrier in a rolling pot, spraying the solution into the alumina carrier in the rolling pot in an atomization mode under the rotating condition, continuing rotating the rolling pot for 30 minutes after the solution is sprayed, then standing for 18 hours, and drying at 110 ℃ for 5 hours to obtain the oxidation state catalyst E. And (3) carrying out vulcanization treatment on the oxidation state catalyst E by adopting an in-situ vulcanization process, introducing 120% of dimethyl disulfide of the theoretical sulfur demand of the catalyst, and carrying out temperature programming in the vulcanization process, wherein the temperature is raised to 320 ℃ and is kept constant for 10 hours to obtain a finished product catalyst E.

Comparative example 2

Preparing 80mL of aqueous solution containing 30.3g of molybdenum trioxide, 17.9g of basic cobalt carbonate, 0.6g of ethylene glycol and 2.0g of citric acid, putting 100g of alumina carrier in a rolling pot, spraying the solution into the alumina carrier in the rolling pot in an atomization mode under the rotating condition, continuing rotating the rolling pot for 30 minutes after the solution is sprayed, then standing for 18 hours, and drying at 110 ℃ for 5 hours to obtain the oxidation state catalyst F. Carrying out vulcanization treatment on the oxidation state catalyst F by adopting an in-situ vulcanization process, wherein the amount of introduced dimethyl disulfide is 120% of the theoretical sulfur demand of the catalyst, and the vulcanization process adopts temperature programming, and the temperature is raised to 320 ℃ and kept constant for 10 hours to obtain the finished product catalyst F.

Comparative example 3

Preparing 80mL of aqueous solution containing 29.0G of molybdenum trioxide, 14.5G of basic cobalt carbonate, 1.5G of glycerol and 0.5G of oxalic acid, putting 100G of alumina carrier in a rolling pot, spraying the solution into the alumina carrier in the rolling pot in an atomization mode under the rotating condition, after the solution is sprayed, continuously rotating the rolling pot for 30 minutes, then standing for 18 hours, and drying at 110 ℃ for 5 hours to obtain the oxidation state catalyst G. Carrying out vulcanization treatment on the oxidation state catalyst G by adopting an in-situ vulcanization process, introducing dimethyl disulfide accounting for 120% of the theoretical sulfur demand of the catalyst, and carrying out temperature programming in the vulcanization process, wherein the temperature is raised to 320 ℃ and is kept constant for 10 hours, so as to obtain a finished product catalyst G.

Comparative example 4

100g of alumina carrier (water absorption rate of 80mL/100 g) is placed in a rolling pot, under the condition of rotation, 80mL of aqueous solution containing 16.7g of basic nickel carbonate, 6.5g of molybdenum trioxide, 27.3g of ammonium metatungstate, 0.3g of ethylene glycol and 2.2g of citric acid is sprayed into the alumina carrier in the rolling pot in an atomizing mode, after the solution is sprayed, the rolling pot is rotated for 30 minutes continuously, and drying is carried out for 4 hours at 110 ℃ to prepare the oxidation state catalyst H. Carrying out vulcanization treatment on the oxidation state catalyst H by adopting an in-situ vulcanization process, introducing dimethyl disulfide accounting for 120% of the theoretical sulfur demand of the catalyst, and carrying out temperature programming in the vulcanization process, raising the temperature to 320 ℃ and keeping the temperature for 10 hours to obtain the finished product catalyst H.

Comparative example 5

The catalyst E, F, G, H was evaluated in the same manner as in example 5.

Example 6

The results of comparing the physical and chemical properties of the catalysts prepared in the above examples with those of the catalysts prepared in the above examples, which were operated in a small-sized hydrogenation apparatus for 600 hours, are shown in tables 2 and 3.

TABLE 2 catalyst key Properties

TABLE 3 test results of the catalysts

The results in Table 3 show that the catalyst of the invention has better hydrotreating activity and better ultra-deep desulfurization and denitrification performance compared with the comparative catalyst.