阅读说明：本技术 一种加氢脱残炭催化剂的制备方法 (Preparation method of hydrogenation carbon residue removal catalyst ) 是由 季洪海 凌凤香 王少军 张会成 沈智奇 于 2019-04-23 设计创作，主要内容包括：本发明公开了一种加氢脱残炭催化剂的制备方法,包括如下内容：(1)将扩孔剂与拟薄水铝石混合,得到混合物A；(2)将偏高岭土、碳酸氢铵和水混合,密封晶化,晶化后物料经干燥、焙烧,脱铝处理,干燥得到物料B；(3)混合物A经滚球成型,得到前驱体I；(4)将物料B与前驱体I混合,进行滚球成型,然后干燥、焙烧,然后负载活性组分,得到加氢脱残炭催化剂。该方法制备的催化剂具有较高的大孔含量及适宜的表面酸性,该加氢脱残炭催化剂具有较高的脱残炭活性的同时具有较高的加氢脱硫、脱氮活性。(The invention discloses a preparation method of a hydrogenation carbon residue removal catalyst, which comprises the following steps: (1) mixing a pore-expanding agent with pseudo-boehmite to obtain a mixture A; (2) mixing metakaolin, ammonium bicarbonate and water, sealing and crystallizing, drying, roasting and dealuminizing the crystallized material, and drying to obtain a material B; (3) forming the mixture A by rolling balls to obtain a precursor I; (4) and mixing the material B with the precursor I, carrying out ball rolling molding, then drying, roasting, and then loading an active component to obtain the hydrogenation carbon residue removal catalyst. The catalyst prepared by the method has high macroporous content and proper surface acidity, and the hydrogenation carbon residue removal catalyst has high carbon residue removal activity and high hydrodesulfurization and denitrification activity.)

1. The preparation method of the hydrogenation carbon residue removal catalyst is characterized by comprising the following steps: mixing a pore-expanding agent with pseudo-boehmite to obtain a mixture A; (2) mixing metakaolin, ammonium bicarbonate and water, sealing and crystallizing, drying, roasting and dealuminizing the crystallized material, and drying to obtain a material B; (3) forming the mixture A by rolling balls to obtain a precursor I; (4) and mixing the material B with the precursor I, carrying out ball rolling molding, then drying, roasting, and then loading an active component to obtain the hydrogenation carbon residue removal catalyst.

2. The method of claim 1, wherein: the pore-expanding agent in the step (1) is one or more of graphite, activated carbon, starch or cellulose, and the mass ratio of the pore-expanding agent to the pseudo-boehmite is 1:100-1: 20.

3. The method of claim 1, wherein: the mass ratio of the ammonium bicarbonate to the metakaolin in the step (2) is 1.5:1-5.0:1, and the mass ratio of the water to the total of the metakaolin and the ammonium bicarbonate is 2:1-4: 1.

4. The method of claim 1, wherein: the sealing crystallization conditions in the step (2) are as follows: the temperature is 120-160 ℃, and the crystallization time is 4-8 hours.

5. The method of claim 1, wherein: the drying temperature in the step (2) is 100-160 ℃, and the drying time is 6-10 hours; the roasting temperature is 600-850 ℃, and the roasting time is 4-8 hours.

6. The method of claim 1, wherein: the dealuminization treatment in the step (2) is carried out in an acidic solution, the acidic solution is nitric acid, hydrochloric acid or phosphoric acid water solution, the mass percent concentration of the solution is 15-30%, and the liquid-solid mass ratio of the dealuminization treatment is 20:1-40: 1.

7. The method according to claim 1 or 6, characterized in that: the dealuminization treatment in the step (2) is carried out under the ultrasonic condition, the ultrasonic treatment temperature is 30-60 ℃, the frequency during ultrasonic treatment is 40-80kHz, and the treatment time is 2-6 hours.

8. The method of claim 1, wherein: the material B in the step (2) has a columnar structure, the length is 1-5 mu m, the diameter is 100-500nm, the silicon-aluminum ratio is 6.5:1-8.5:1, the silicon-aluminum ratio is the mass ratio of silicon oxide to aluminum oxide, the total acid amount is 0.3-0.5mmol/g, the weak acid content is 0.05-0.15mmol/g, the medium strong acid content is 0.05-0.15mmol/g, the strong acid content is 0.1-0.25mmol/g, and the specific surface area is 200-350-^m2The pore volume is 0.3-0.5mL/g, and the diameter of several pores is 10-30 nm.

9. The method of claim 1, wherein: the rolling ball forming in the step (3) is carried out in a turntable forming machine, and the rotation operating conditions of the turntable forming machine are as follows: the inclination angle of the rotary table is 40-70 degrees, and the rotating speed of the rotary table is 10-30 rpm; the molding time of the material in the turntable is 5-30 min; spraying aqueous solution containing a glue solvent into the material in the forming process; the aqueous solution of the glue-containing solvent is one or a mixture of several of aqueous solutions of nitric acid, phosphoric acid, oxalic acid or acetic acid, and the mass percentage concentration of the solution is 1-3%.

10. The method of claim 1, wherein: the active component in the step (4) is VIB group and/or VIII group metal, the VIB group metal is selected from one or more of W, Mo, and the VIII group metal is selected from one or more of Co and Ni.

Technical Field

The invention relates to the field of catalyst preparation, in particular to a preparation method of a hydrogenation carbon residue removal catalyst.

Background

The residual oil contains the heaviest components of crude oil, including various complex hydrocarbons, as well as high concentrations of sulfur, nitrogen, and metals (primarily nickel and vanadium), and is characterized by high viscosity, high carbon residue, and the like. Because the carbon residue value of the produced oil is one of the key indexes influencing the feed ratio of a downstream FCC device and is also an important reason for catalyst deactivation, the hydrogenation and carbon residue removal of residual oil is an important link in the hydrotreating process. The precursor of residual carbon is mainly composed of larger condensed ring aromatic hydrocarbon in asphaltene or colloid, and the capability of the catalyst for the hydroconversion of the substances needs to be improved in order to remove the impurities as far as possible. The catalyst thus selected must have a large pore size and pore volume, a suitable specific surface area and a suitable surface acidity.

CN1321726A discloses a residual oil hydrotreating catalyst and a preparation method thereof, in particular to a residual oil hydrodenitrogenation and hydrodecarbonization catalyst and a preparation method thereof. The preparation method of the catalyst comprises the steps of mixing nickel-containing metal salts in the kneading process of monohydrate aluminum hydroxide to provide the nickel content required by the catalyst, then adding a neutral solution for mixing, adding an acidic solution for kneading, and preparing the Al containing nickel and silicon₂O₃The carrier is then loaded with the molybdenum-containing compound once by the impregnation method. The catalyst prepared by the method has high 6-8nm pore channel content and relatively less macroporous content, is not beneficial to the diffusion of macromolecular reactants, and in addition, the surface acid amount of the carrier needs to be further improved.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a preparation method of a hydrogenation carbon residue removal catalyst, the catalyst prepared by the method has higher macroporous content and proper surface acidity, and the hydrogenation carbon residue removal catalyst has higher carbon residue removal activity and simultaneously has higher hydrodesulfurization and denitrification activity.

The preparation method of the hydrogenation carbon residue removal catalyst comprises the following steps:

(1) mixing a pore-expanding agent with pseudo-boehmite to obtain a mixture A;

(2) mixing metakaolin, ammonium bicarbonate and water, sealing and crystallizing, drying, roasting and dealuminizing the crystallized material, and drying to obtain a material B;

(3) forming the mixture A by rolling balls to obtain a precursor I;

(4) and mixing the material B with the precursor I, carrying out ball rolling molding, then drying, roasting, and then loading an active component to obtain the hydrogenation carbon residue removal catalyst.

In the method of the present invention, the pseudoboehmite described in the step (1) may be a pseudoboehmite prepared by any method, for example, prepared by a precipitation method, an aluminum alkoxide hydrolysis method, an inorganic salt sol-gel method, a hydrothermal method, a vapor deposition method, and the like. The pore-expanding agent can be one or more of graphite, activated carbon, starch and cellulose, preferably starch, and the mass ratio of the pore-expanding agent to the pseudo-boehmite is 1:100-1: 20.

In the method of the present invention, the metakaolin in the step (2) is obtained by activating kaolin, wherein the activation temperature is generally 750-.

In the method, the mass ratio of the ammonium bicarbonate to the metakaolin in the step (2) is 1.5:1-5.0:1, and the mass ratio of the water to the total mass of the metakaolin and the ammonium bicarbonate is 2:1-4: 1; the metakaolin, the ammonium bicarbonate and the water can be added and mixed in any sequence, for example, the water can be added into the mixture of the metakaolin and the ammonium bicarbonate, or the metakaolin is immersed into the aqueous solution of the ammonium bicarbonate.

In the method of the invention, the sealing crystallization conditions in the step (2) are as follows: the temperature is 120-160 ℃, and the crystallization time is 4-8 hours; generally in an autoclave. The drying temperature is 100-160 ℃, the drying time is 6-10 hours, the roasting temperature is 600-850 ℃, and the roasting time is 4-8 hours.

In the method, the dealuminization treatment in the step (2) is generally carried out in an acidic solution, the acidic solution is a nitric acid, hydrochloric acid or phosphoric acid aqueous solution, preferably a hydrochloric acid solution, the mass percentage concentration of the solution is 15-30%, and the liquid-solid mass ratio is 20:1-40: 1; further preferably, the ultrasonic treatment is carried out under ultrasonic conditions, wherein the ultrasonic treatment temperature is 30-60 ℃, the frequency during ultrasonic treatment is 40-80kHz, and the treatment time is 2-6 hours. The drying temperature after dealuminization is 100-160 ℃, and the drying time is 6-10 hours.

In the method, the material B in the step (2) has a columnar structure, the length is 1-5 mu m, the diameter is 100-500nm, the silicon-aluminum ratio is 6.5:1-8.5:1, the silicon-aluminum ratio is the mass ratio of silicon oxide to aluminum oxide, the total acid amount is 0.3-0.5mmol/g, the weak acid content is 0.05-0.15mmol/g, the medium strong acid content is 0.05-0.15mmol/g, the strong acid content is 0.1-0.25mmol/g, and the specific surface area is 200-350m²The pore volume is 0.3-0.5mL/g, and the diameter of several pores is 10-30 nm.

In the method, the rolling ball forming in the step (3) is carried out in a turntable forming machine, and the rotation operating conditions of the turntable forming machine are as follows: the inclination angle of the rotary table is 40-70 degrees, and the rotating speed of the rotary table is 10-30 rpm; the molding time of the material in the turntable is 5-30 min. Spraying aqueous solution containing a glue solvent into the material in the forming process; the aqueous solution of the glue-containing solvent is one or a mixture of several of aqueous solutions of nitric acid, phosphoric acid, oxalic acid and acetic acid, the mass percentage concentration of the solution is 1-3%, and the aqueous solution of the acetic acid is preferred.

In the method, the drying time in the step (4) is 1-5 hours, preferably 2-4 hours, the drying temperature is 60-180 ℃, and preferably 80-150 ℃; the roasting temperature is 350-800 ℃, preferably 500-700 ℃, and the roasting time is 2-6 hours, preferably 2-4 hours.

In the method, the active component in the step (4) is a VIB group metal and/or a VIII group metal, the VIB group metal is selected from W, Mo or more, and the VIII group metal is selected from Co and Ni or more. The loading mode adopts an impregnation method, the preparation of the impregnation solution is well known to those skilled in the art, the content of the VIB group metal in the impregnation solution is 5-25g/100mL calculated by metal oxides, and the content of the VIII group metal in the impregnation solution is 1-10g/100mL calculated by metal oxides. The impregnation can be carried out by an equal volume impregnation or a supersaturation impregnation. The drying temperature is 80-160 ℃, the drying time is 6-10 hours, and the roasting is 4-8 hours at the temperature of 450-550 ℃.

Compared with the prior art, the hydrogenation carbon residue removal catalyst has the following advantages:

1. in the preparation process of the catalyst, metakaolin is subjected to ammonium bicarbonate heat treatment to obtain a micron-sized columnar silicon-aluminum composite oxide, then the composite oxide is subjected to dealumination treatment in an acidic solution, more unsaturated aluminum ions and silicon oxide coordinated on the surface of the silicon-aluminum material are exposed due to the removal of aluminum, and the silicon-aluminum material with high acid content and proper acid strength distribution is obtained, on the other hand, corrosion points are formed on the surface of the silicon-aluminum composite oxide due to the removal of aluminum, and the pore channel content of the material is increased by 10-30 nm.

2. When the carrier rolling ball is molded, different types of molding materials are sequentially added, and the two materials have different pore channel structures and surface properties, so that the pore channels and the acid properties of the prepared spherical alumina carrier show different distribution rules, and the spherical alumina carrier has a structure that the pore channels are from large to small and the acid content is from high to bottom from the surface to the inside, namely the pore channels on the surface of the spherical alumina carrier are formed by interweaving columnar silicon-aluminum composite oxides, the pore channels are large and the acid content is high; the internal pore canal is formed by stacking pseudo-boehmite particles, and a proper amount of physical pore-expanding agent is added for expanding pores, so that the pore structure is moderate, and the acid content is low.

(3) When the alumina is used as a carrier to prepare the hydrogenation carbon residue removal catalyst, the prepared hydrogenation carbon residue removal catalyst has higher carbon residue removal activity and simultaneously has higher hydrogenation desulfurization and denitrification activity due to the unique pore channel structure and the surface acid property.

Drawings

FIG. 1 is an SEM image of material B1.

Detailed Description

The following examples are provided to further illustrate the technical solutions of the present invention, but the present invention is not limited to the following examples. In the present invention, wt% is a mass fraction. The pseudo-boehmite adopted in the embodiment and the comparative example of the invention is self-made by a method of using aluminum sulfate and sodium metaaluminate.

Application N₂Physical adsorption-desorption characterization of pore structures of samples of examples and comparative examples, the specific operations are as follows: adopting ASAP-2420 type N₂And the physical adsorption-desorption instrument is used for characterizing the pore structure of the sample. A small amount of samples are taken to be treated for 3 to 4 hours in vacuum at the temperature of 300 ℃, and finally, the product is placed under the condition of liquid nitrogen low temperature (-200 ℃) to be subjected to nitrogen absorption-desorption test. Wherein the specific surface area is obtained according to a BET equation, and the distribution rate of the pore volume and the pore diameter below 50nm is obtained according to a BJH model.

Mercury pressing method: the pore diameter distribution of the samples of the examples and the comparative examples is characterized by applying a mercury porosimeter, and the specific operation is as follows: and characterizing the distribution of sample holes by using an American microphone AutoPore9500 full-automatic mercury porosimeter. The samples were dried, weighed into an dilatometer, degassed for 30 minutes while maintaining the vacuum conditions given by the instrument, and filled with mercury. The dilatometer was then placed in the autoclave and vented. And then carrying out a voltage boosting and reducing test. The mercury contact angle is 130 degrees, and the mercury interfacial tension is 0.485N.cm^-1The distribution ratio of pore diameter of 100nm or more is measured by mercury intrusion method.

The scanning electron microscope is used for representing the microstructure of a sample, and the specific operation is as follows: and a JSM-7500F scanning electron microscope is adopted to represent the microstructure of the carrier, the accelerating voltage is 5KV, the accelerating current is 20 muA, and the working distance is 8 mm.

Preparation of material B:

(1) preparation of Material B1

200 g of kaolin are activated at 850 ℃ for 5 hours in a high-temperature muffle furnace. Weighing 100g of the activated kaolin and 400 g of ammonium bicarbonate, adding 1500 g of distilled water into the materials, stirring for 20 minutes, transferring the mixed materials into a high-pressure kettle, sealing, heating to 80 ℃ at a speed of 10 ℃/min, keeping the temperature for 3 hours, heating to 135 ℃ at a speed of 5 ℃/min, keeping the temperature for 5 hours, drying the materials at 110 ℃ for 6 hours, and roasting at 750 ℃ for 5 hours.

Weighing 50 g of the materials, placing inAdding 1500 g of hydrochloric acid solution with the mass percentage concentration of 25% into a beaker, placing the beaker into an ultrasonic container for ultrasonic treatment, wherein the ultrasonic frequency is 70kHz, the treatment temperature is 45 ℃, the treatment time is 3 hours, the treated material is dried for 6 hours at 110 ℃ after liquid-solid separation to obtain a material B1, the length of the material is 2-4 mu m, the diameter is 150 nm, the silicon-aluminum ratio is 7.5:1, the silicon-aluminum ratio is the mass ratio of silicon dioxide to aluminum oxide, the total acid amount is 0.45mmol/g, the weak acid content is 0.1mmol/g, the medium strong acid content is 0.11mmol/g, the strong acid content is 0.23mmol/g, and the specific surface area is 112m²The pore volume is 0.41mL/g, and the diameter of several pores is 15 nm.

(2) Preparation of Material B2

The same procedure as for the preparation of material B1 was repeated, except that the activation temperature of kaolin was 900 ℃, the amount of ammonium bicarbonate added was 300 g, the amount of distilled water added was 1000 g, the sealing heat treatment temperature was 145 ℃ and the treatment time was 6 hours. The mass percentage concentration of the hydrochloric acid is 20%, the addition amount is 1200 g, the frequency during ultrasonic treatment is 60kHz, the treatment temperature is 40 ℃, the treatment time is 4 hours, and a material B2 is prepared, wherein the length of the material is 1-3 mu m, the diameter is 120-240nm, the silicon-aluminum ratio is 8.0:1, the silicon-aluminum ratio is the mass ratio of silicon dioxide to aluminum oxide, the total acid amount is 0.47mmol/g, the weak acid content is 0.12mmol/g, the medium strong acid content is 0.12mmol/g, the strong acid content is 0.23mmol/g, and the specific surface area is 109m²The pore volume is 0.45mL/g, and the diameter of several pores is 12.5 nm.

(3) Preparation of Material B3

The same procedure as for the preparation of material B1 was repeated, except that the activation temperature of kaolin was 800 ℃, the amount of ammonium bicarbonate added was 200 g, the amount of distilled water added was 1050 g, the sealing heat treatment temperature was 155 ℃ and the treatment time was 4 hours. The mass percentage concentration of the hydrochloric acid is 15 percent, the addition amount is 1000 g, the frequency during ultrasonic treatment is 50kHz, the treatment temperature is 35 ℃, the treatment time is 5 hours, B3 is prepared, the length of the material is 2-5 mu m, the diameter is 100-200nm, the silicon-aluminum ratio is 7.2:1, the silicon-aluminum ratio is the mass ratio of silicon dioxide to aluminum oxide, the total acid amount is 0.41mmol/g, the weak acid content is 0.1mmol/g, the medium strong acid content is 0.12mmol/g, the strong acid content is 0.19mmol/g, and the specific surface area is 132m²A pore volume of 0.43mL/g and a pore diameter of several poresIs 15 nm.