Alumina carrier as well as preparation method and application thereof

Abstract

The invention provides an alumina carrier as well as a preparation method and application thereof. The method comprises the following steps: (1) purchasing or preparing pseudo-boehmite powder; (2) mixing gelatin, a fluorine-containing compound and water to prepare a mixed solution, and performing cooling and curing treatment to obtain composite hydrogel; and (3) uniformly mixing the pseudo-boehmite powder obtained in the step (1) and the composite hydrogel obtained in the step (2), and sequentially carrying out forming, drying and roasting treatment to obtain the alumina carrier. The fluorine element is introduced to a specific position by utilizing the characteristic of low-temperature solidification of gelatin, so that the distribution condition of acid sites in pores of the alumina carrier can be modulated, and the activity of the catalyst is further improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of petroleum chemical industry, and particularly relates to an alumina carrier and a preparation method and application thereof. BACKGROUND

[0002] With the aggravation of the heavy and poor trend of petroleum resources, the properties of crude oil are getting worse, and poor heavy oil becomes an important raw material in the future. Hydroprocessing is one of the important technical means for processing poor heavy oil, and the above factors put higher requirements on the hydroprocessing catalyst. At present, the hydroprocessing catalyst is mainly a supported catalyst, and alumina is usually used as the carrier. In order to further improve the performance of the catalyst, the alumina carrier often needs to be modified.

[0003] Studies have shown that the modification of the alumina carrier by fluorine elements can enhance the acid properties of the alumina carrier, and thus improve the performance of the catalyst. CN114471503A provides a hydroprocessing catalyst carrier, a catalyst and a preparation method and application thereof. The preparation method of the hydroprocessing catalyst carrier comprises the following steps: (1) acid treatment, washing, and drying of pseudo-boehmite to obtain acid-treated pseudo-boehmite; (2) dispersing the material obtained in step (1) in a solvent with polyvinylidene fluoride and a blending agent, and then performing heat treatment, washing, and drying to obtain modified pseudo-boehmite; (3) mixing and stirring the modified pseudo-boehmite obtained in step (2) with an aluminum source solution, and then performing washing and drying to obtain structure-remodeled modified pseudo-boehmite; and (4) kneading and shaping the material obtained in step (3), and then performing drying and calcination to obtain the hydroprocessing catalyst carrier.

[0004] CN1302848A discloses a hydrogenation catalyst and a preparation method thereof. The catalyst is prepared by loading W and Ni on alumina prepared by a special method. The alumina prepared by the special method is modified by adding fluorine, and one or more than one oxide of boron, silicon, phosphorus, magnesium, titanium, zirconium, and gallium is added. The catalyst contains 18-30 m% of tungsten oxide, 3-8 m% of nickel oxide, 3-10 m% of fluorine, and 1-5 m% of the oxide of boron, silicon, phosphorus, magnesium, titanium, zirconium, and gallium.

[0005] When the above patent modifies the alumina carrier by fluorine elements, fluorine-containing compounds are introduced into the alumina carrier without selection and targeting, and the effect of the fluorine-containing compounds on the adjustment of the acid properties of the alumina carrier is limited. When the catalyst with the above alumina as the carrier is used for heavy oil hydroprocessing, the activity of the catalyst needs to be improved. SUMMARY

[0006] In view of the deficiencies in the prior art, the present application provides an alumina carrier and a preparation method and application thereof, which utilizes the characteristics of gelatin low-temperature coagulation to introduce fluorine elements into specific positions, can adjust the distribution of acidic sites in the pores of the alumina carrier, and further improves the activity of the catalyst.

[0007] The first aspect of the present application provides a preparation method of an alumina carrier, comprising the following contents:

[0008] (1) purchasing or preparing boehmite powder;

[0009] (2) mixing gelatin, a fluorine-containing compound and water to prepare a mixed solution, and then performing a cooling and solidification treatment to obtain a composite hydrogel;

[0010] (3) uniformly mixing the boehmite powder obtained in step (1) and the composite hydrogel obtained in step (2), and then sequentially performing a molding, drying and calcination treatment to obtain the alumina carrier.

[0011] In the above method step (1), the specific process of preparing the boehmite powder is as follows: mixing an aluminum-containing compound solution and an alkaline precipitant to perform a neutralization and gelation reaction, and then performing an aging treatment on the obtained slurry, and then performing a filtration and drying treatment to obtain the boehmite powder.

[0012] In the above method step (1), the aluminum-containing compound used in the aluminum-containing compound solution is selected from at least one of Al2(SO4)3, AlCl3 and Al(NO3)3; the concentration of the aluminum-containing compound solution is not particularly limited, and preferably, the concentration (calculated as alumina) of the aluminum-containing compound solution is 20-200 g / L.

[0013] In the above method step (1), the alkaline precipitant is at least one of NaOH, NH4OH and NaAlO2.

[0014] In the above method step (1), a magnesium-containing additive can also be introduced in the neutralization and gelation reaction, and preferably, the magnesium-containing additive is mixed with water as a bottom solution, and then the aluminum-containing compound solution and the alkaline precipitant are mixed to perform the neutralization and gelation reaction; the magnesium-containing additive is one or more of magnesium sulfate, magnesium nitrate and magnesium chloride; and the addition amount of the magnesium-containing additive (calculated as MgO) is 0.1-5.0 wt%, preferably 0.5-4.5 wt%, based on the weight (calculated as dry basis) of the alumina carrier.

[0015] In the above method step (1), the neutralization and gelation reaction conditions are as follows: the pH value is 7-10, the temperature is 50-95℃, and the time is 30-120 min.

[0016] In the step (1) of the above method, the aging conditions are: temperature 50-90℃, pH value 8-11, time 3-24h; the drying conditions are: drying at 50-90℃ for 3-10h, and then drying at 90-250℃ for 3-6h.

[0017] In the step (2) of the above method, the gelatin is selected from one or more of marine gelatin, pig gelatin, cow gelatin and chicken gelatin, and has an industrial grade or food grade purity; the molecular weight of the gelatin is 10000-70000, preferably 20000-50000; the amount of the gelatin added is 2-8wt%, preferably 3-6wt%, based on the weight of the alumina carrier (dry basis).

[0018] In the step (2) of the above method, the fluorine-containing compound is one or more of water-soluble fluorine-containing compounds such as ammonium fluoride, ammonium fluorosilicate, hydrogen fluoride, ammonium bifluoride, calcium fluoride and sodium fluoride, preferably ammonium fluorosilicate and / or ammonium fluoride; the amount of the fluorine-containing compound (in terms of elementary substance) added is 0.05wt%-1wt%, preferably 0.1wt%-0.6wt%, based on the weight of the alumina carrier (dry basis).

[0019] In the step (2) of the above method, the specific operation process of mixing the gelatin and the fluorine-containing compound with water is as follows: the gelatin and the fluorine-containing compound are added to water at 5-20℃, and then stirred at 10-140r / min and treated at 30-70℃ until completely dissolved.

[0020] In the step (2) of the above method, the cooling and solidification treatment conditions are as follows: temperature 2-20℃, time 2-6h. Through the cooling and solidification treatment, the mixed solution is converted into a gel state, thereby forming a composite hydrogel; the fluorine element is uniformly distributed in the composite hydrogel.

[0021] In the step (3) of the above method, the mass ratio of the boehmite powder and the composite hydrogel is 0.66-10, preferably 0.8-5.

[0022] In the step (3) of the above method, the mixing and molding processes are both carried out at a temperature of 1-30℃, preferably 15-25℃.

[0023] In the step (3) of the above method, the molding can be carried out by any one of molding means such as drop ball molding, rolling ball granulation, extrusion molding and tablet molding, preferably extrusion molding; the shape of the molding can be any one of spherical, strip-shaped and tablet-shaped, preferably any one of spherical and strip-shaped.

[0024] In the step (3) of the above method, a forming aid can be added in the forming process, the forming aid is at least one of an extrusion aid, a binder and a peptizing agent; the extrusion aid is one or more of amaranth powder, starch and methyl cellulose, preferably amaranth powder; the binder is one or more of inorganic oxides such as titanium oxide, aluminum oxide and zirconium oxide; the peptizing agent is an organic acid and / or an inorganic acid, specifically, the organic acid is nitric acid and / or hydrochloric acid, and the inorganic acid is at least one of oxalic acid, acetic acid and propionic acid.

[0025] In the step (3) of the above method, the drying time is 2h-10h, preferably 3h-6h, the drying temperature is 80℃-160℃, preferably 100℃-130℃; the calcination temperature is 400℃-700℃, preferably 450℃-680℃, and the calcination time is 1h-10h, preferably 2h-6h.

[0026] The second aspect of the present application provides the alumina carrier obtained by the above preparation method.

[0027] The third aspect of the present application provides a hydroprocessing catalyst containing the above alumina carrier.

[0028] The fourth aspect of the present application provides the use of the above hydroprocessing catalyst in a hydroprocessing process.

[0029] Compared with the prior art, the present application has the following beneficial effects:

[0030] The preparation method of the alumina carrier provided by the present application mixes gelatin and a fluorine-containing compound with water to prepare a mixed solution, and then performs a cooling and solidification treatment to convert the mixed solution into a "solid-like" gel state to obtain a composite hydrogel; then the pseudo-boehmite powder is mixed with the composite hydrogel, and the mixture is sequentially subjected to a forming, drying and calcination treatment to obtain the alumina carrier. In this process, the composite hydrogel containing fluorine elements can play the role of a pore expander to form secondary pores, so that most of the fluorine elements are enriched in the secondary pores to directionally modify the inner surface of the secondary pore channels. In this way, the distribution of the acidic sites in the pore channels of the alumina carrier is adjusted, and the activity of the catalyst is improved. DETAILED DESCRIPTION

[0031] The present application will be described in detail below by way of examples, but the present application is not limited to the following examples. In addition, in the present application, % is the weight percentage unless otherwise specified.

[0032] In the present application, the gelatin used in the examples and comparative examples is purchased from McKin, CAS: 9000-70-8. The molecular weight of the gelatin is 10000-50000.

[0033] In the present application, the mixing in step (3) and the shaping process in the examples and comparative examples are all carried out at room temperature of 25℃.

[0034] Example 1

[0035] (1) 1L of deionized water and 3.67g of magnesium nitrate were added into a reaction tank as a bottom solution, and the mass fraction of magnesium oxide was 0.5wt% based on the weight of the aluminum oxide carrier (dry basis). 200g / L of aluminum sulfate and 100g / L of sodium metaaluminate solution were respectively placed in the raw material tank, the aluminum sulfate solution was injected into the reaction tank at a rate of 10mL / min, and the sodium metaaluminate solution was injected at the same time and its rate was adjusted to keep the pH value of the solution in the reaction tank constant at 8.0, the temperature of the reaction tank was controlled at 60℃, and the neutralization and gelation reaction was completed after 120min. The temperature of the reaction tank was kept constant at 85℃ and the pH value was kept constant at 8.5, and the aging treatment was carried out for 5h, then deionized water was washed for 3 times, the filter cake was dried at 60℃ for 3h, and then dried at 110℃ for 5h, to obtain a boehmite powder.

[0036] (2) The gelatin and ammonium fluoride were added into cold water at 15℃, then treated under the condition of stirring at 80r / min and temperature of 60℃ until completely dissolved; then solidified at 10℃ for 4h to obtain a composite hydrogel containing gelatin and fluorine; the amount of gelatin added was 2wt% and the amount of ammonium fluoride (calculated as fluorine) added was 0.1wt% based on the weight of the aluminum oxide carrier (dry basis).

[0037] (3) 200g of the boehmite powder prepared in step (1) (dry basis), 200g of the composite hydrogel containing gelatin and fluorine prepared in step (2), 4g of sesbania powder and 4g of citric acid were mixed uniformly to obtain a mixture. 9.5g of dilute nitric acid with a concentration of 68wt% was weighed and diluted to 20mL with deionized water to prepare an acidic solution. The mixture was kneaded for 15min, then rolled for 20min, and the acidic solution was added to the mixture during the rolling process, and water was added moderately according to the dryness of the powder during the process. Finally, the mixture was extruded into a strip with a diameter of 1.7mm using a three-leaf clover hole plate, dried at 120℃ for 4h, and then calcined at 600℃ for 6h. The calcined carrier was denoted as Z1.

[0038] Example 2

[0039] (1) 1L of deionized water and 26.9g of magnesium sulfate were added into a reaction tank as a bottom solution, and the mass fraction of magnesium oxide was 4.5wt% based on the weight of the aluminum oxide carrier (dry basis). 200g / L of aluminum sulfate and 100g / L of sodium metaaluminate solution were respectively placed in raw material tanks, the aluminum sulfate solution was injected into the reaction tank at a rate of 10mL / min, while the sodium metaaluminate solution was injected and its rate was adjusted to keep the pH value of the solution in the reaction tank constant at 8.0, and the temperature of the reaction tank was controlled at 60℃, and the neutralization and gelation reaction was completed after 120min. The reaction tank was treated at a constant temperature of 85℃ and a constant pH value of 8.5 for 5h, then washed with deionized water for 3 times, filtered, and the filter cake was dried at 60℃ for 3h, and then dried at 110℃ for 5h to obtain a boehmite powder.

[0040] (2) Gelatin and ammonium fluoride were added into cold water at 15℃, then treated under the conditions of stirring at 80r / min and temperature of 60℃ until completely dissolved; then cooled and solidified at 15℃ for 4h to obtain a composite hydrogel containing gelatin and fluorine; the amount of gelatin added was 8wt% and the amount of ammonium fluoride (calculated as fluorine) added was 0.06wt% based on the weight of the aluminum oxide carrier (dry basis).

[0041] (3) 200g of the boehmite powder prepared in step (1) (dry basis), 40g of the composite hydrogel containing gelatin and fluorine prepared in step (2), 4g of sesbania powder and 4g of citric acid were mixed to obtain a mixture. 9.5g of dilute nitric acid with a concentration of 68wt% was weighed and diluted to 20mL with deionized water to prepare an acidic solution. The mixture was kneaded for 15min, then rolled for 20min, and the acidic solution was added to the mixture during the rolling process, and water was added as needed according to the dryness of the powder. Finally, the mixture was extruded into a strip with a three-leaf clover hole plate with a diameter of 1.7mm, dried at 120℃ for 4h, and then calcined at 600℃ for 6h. The calcined carrier was denoted as Z2.

[0042] Example 3

[0043] (1) 1L of deionized water and 26.9g of magnesium sulfate were added into a reaction tank as a bottom solution, and the mass fraction of magnesium oxide was 4.5wt% based on the weight of the aluminum oxide carrier (dry basis). 200g / L of aluminum sulfate and 100g / L of sodium metaaluminate solution were respectively placed in raw material tanks, the aluminum sulfate solution was injected into the reaction tank at a rate of 10mL / min, while the sodium metaaluminate solution was injected and its rate was adjusted to keep the pH value of the solution in the reaction tank constant at 8.0, and the temperature of the reaction tank was controlled at 60℃, and the neutralization and gelation reaction was completed after 120min. The reaction tank was treated at a constant temperature of 85℃ and a constant pH value of 8.5 for 5h, then washed with deionized water for 3 times, filtered, and the filter cake was dried at 60℃ for 3h, and then dried at 110℃ for 5h to obtain a boehmite powder.

[0044] (2) Gelatin and ammonium fluoride were added to cold water at 15°C, and then treated under stirring at 80 r / min and at a temperature of 60°C until completely dissolved. Then, the temperature was reduced to 5°C for solidification treatment for 4 h to obtain a composite hydrogel containing gelatin and fluorine. The amount of gelatin added was 4 wt% and the amount of ammonium fluoride (in terms of fluorine element) added was 0.2 wt% based on the weight of the alumina carrier (in terms of dry basis).

[0045] (3) 200 g of the pseudoboehmite powder prepared in step (1) (in terms of dry basis), 100 g of the composite hydrogel containing gelatin and fluorine prepared in step (2), 4 g of sesbania powder and 4 g of citric acid were uniformly mixed to obtain a mixture. 9.5 g of dilute nitric acid with a concentration of 68 wt% was weighed and diluted to 20 mL with deionized water to prepare an acidic solution. The mixture was kneaded for 15 min, and then rolled for 20 min. The acidic solution was added to the mixture during the rolling process, and water was appropriately supplemented according to the dryness of the powder during the process. Finally, the mixture was extruded into a strip through a three-leaf clover hole plate with a diameter of 1.7 mm, and then dried at 120°C for 4 h and calcined at 600°C for 6 h. The carrier after calcination was recorded as Z3.

[0046] Example 4

[0047] (1) 1 L of deionized water and 14.7 g of magnesium nitrate were added to a reaction tank as a bottom solution. The mass fraction of magnesium oxide was 2% based on the weight of the alumina carrier (in terms of dry basis). 200 g / L of aluminum sulfate and 100 g / L of sodium metaaluminate solution were respectively placed in the raw material tank. The aluminum sulfate solution was injected into the reaction tank at a rate of 10 mL / min, and the sodium metaaluminate solution was injected into the reaction tank while adjusting the rate to keep the pH value of the solution in the reaction tank constant at 8.0. The temperature of the reaction tank was controlled at 60°C, and the neutralization and gelation reaction was completed after 120 min. Aging treatment was performed at a constant temperature of 85°C and a constant pH value of 8.5 in the reaction tank for 5 h, and then washed with deionized water for 3 times. The filter cake was dried at 60°C for 3 h, and then dried at 110°C for 5 h to obtain the pseudoboehmite powder.

[0048] (2) Gelatin and ammonium fluoride were added to cold water at 15°C, and then treated under stirring at 80 r / min and at a temperature of 60°C until completely dissolved. Then, the temperature was reduced to 15°C for solidification treatment for 4 h to obtain a composite hydrogel containing gelatin and fluorine. The amount of gelatin added was 6 wt% and the amount of ammonium fluoride (in terms of fluorine element) added was 0.6 wt% based on the weight of the alumina carrier (in terms of dry basis).

[0049] (3) Take 200 g of the pseudo-boehmite powder prepared in step (1) (on a dry basis), 50 g of the composite hydrogel containing gelatin and fluorine prepared in step (2), 4 g of sesbania powder, and 4 g of citric acid, mix them uniformly to obtain a mixture. Take 9.5 g of dilute nitric acid with a concentration of 68 wt% and dilute it to 20 mL with deionized water to prepare an acidic solution. Knead the mixture for 15 min, then roll it for 20 min. Add the acidic solution to the mixture during the rolling process, and appropriately supplement water according to the dryness of the powder. Finally, extrude the mixture into a strip through a three-leaf clover hole plate with a diameter of 1.7 mm. After drying at 120°C for 4 h, calcine it at 600°C for 6 h. The calcined carrier is denoted as Z4.

[0050] Example 5

[0051] (1) Put 1 L of deionized water and 17.9 g of magnesium sulfate into a reaction tank as a bottom solution. The mass fraction of magnesium oxide is 3% based on the weight of the aluminum oxide carrier (on a dry basis). Put 200 g / L of aluminum sulfate and 100 g / L of sodium metaaluminate solution into the raw material tank, respectively. Inject the aluminum sulfate solution into the reaction tank at a rate of 10 mL / min, while injecting the sodium metaaluminate solution and adjusting its rate to keep the pH value of the solution in the reaction tank constant at 8.0. Control the temperature of the reaction tank at 60°C. After 120 min, end the neutralization and gelation reaction. Perform aging treatment at a constant temperature of 85°C and a constant pH value of 8.5 for 5 h in the reaction tank, then wash it with deionized water for 3 times. After filtration, dry the filter cake at 60°C for 3 h, and then at 110°C for 5 h to obtain the pseudo-boehmite powder.

[0052] (2) Put gelatin and ammonium fluoride into cold water at 15°C, then perform treatment under stirring at 80 r / min and at a temperature of 60°C until complete dissolution. Then perform cooling and solidification treatment at 15°C for 4 h to obtain the composite hydrogel containing gelatin and fluorine. The amount of gelatin added is 8 wt% based on the weight of the aluminum oxide carrier (on a dry basis), and the amount of ammonium fluoride (in terms of fluorine element) added is 0.4 wt%.

[0053] (3) Take 200 g of the pseudo-boehmite powder prepared in step (1) (on a dry basis), 200 g of the composite hydrogel containing gelatin and fluorine prepared in step (2), 4 g of sesbania powder, and 4 g of citric acid, mix them uniformly to obtain a mixture. Take 9.5 g of dilute nitric acid with a concentration of 68 wt% and dilute it to 20 mL with deionized water to prepare an acidic solution. Knead the mixture for 15 min, then roll it for 20 min. Add the acidic solution to the mixture during the rolling process, and appropriately supplement water according to the dryness of the powder. Finally, extrude the mixture into a strip through a three-leaf clover hole plate with a diameter of 1.7 mm. After drying at 120°C for 4 h, calcine it at 600°C for 6 h. The calcined carrier is denoted as Z5.

[0054] Comparative Example 1

[0055] The difference from Example 4 is that no gelatin is added in step (2) and only the fluorine-containing compound is mixed with water to prepare a mixed solution. The details are as follows.

[0056] (1) 1 L of deionized water and 14.7 g of magnesium nitrate were added into a reaction tank as a bottom solution, with the mass fraction of magnesium oxide being 2 wt% based on the weight of the alumina carrier (dry basis). A 200 g / L aluminum sulfate solution and a 100 g / L sodium metaaluminate solution were respectively placed in raw material tanks, the aluminum sulfate solution was injected into the reaction tank at a rate of 10 mL / min, and the sodium metaaluminate solution was injected into the reaction tank while adjusting the rate to keep the pH value of the solution in the reaction tank constant at 8.0. The temperature of the reaction tank was controlled at 60°C, and the neutralization and gelation reaction was completed after 120 min. Aging treatment was performed at a constant temperature of 85°C and a constant pH value of 8.5 for 5 h, followed by deionized water washing for 3 times, filtration, drying of the filter cake at 60°C for 3 h, and then drying at 110°C for 5 h to obtain a boehmite powder.

[0057] (2) 2.3 g of ammonium fluoride was dissolved in water to prepare a fluorine-containing solution of 100 g. The amount of ammonium fluoride (in terms of fluorine element) was 0.6 wt% based on the weight of the alumina carrier (dry basis).

[0058] (3) 200 g of the boehmite powder prepared in step (1) (dry basis), 100 g of the fluorine-containing solution prepared in step (2), 4 g of sesbania powder, and 4 g of citric acid were mixed to obtain a mixture. 9.5 g of dilute nitric acid with a concentration of 68 wt% was weighed and diluted to 20 mL with deionized water to prepare an acidic solution. The mixture was kneaded for 15 min, and then rolled for 20 min. The acidic solution was added to the mixture during the rolling process, and water was appropriately supplemented according to the dryness of the powder. Finally, the mixture was extruded into a strip through a three-leaf clover hole plate with a diameter of 1.7 mm, dried at 120°C for 4 h, and then calcined at 600°C for 6 h. The calcined carrier is denoted as DZ1.

[0059] Comparative Example 2

[0060] The difference from Example 4 is that no gelatin is used in step (2), but polyethylene glycol 8000 is used instead. The details are as follows.

[0061] (1) Put 1 L of deionized water and 14.7 g of magnesium nitrate into a reaction tank as a bottom solution, with the mass fraction of magnesium oxide being 2% based on the weight of the alumina carrier (dry basis). Put 200 g / L of aluminum sulfate and 100 g / L of sodium metaaluminate solutions into raw material tanks respectively, inject the aluminum sulfate solution into the reaction tank at a rate of 10 mL / min, and inject the sodium metaaluminate solution while adjusting the rate to keep the pH value of the solution in the reaction tank constant at 8.0, control the temperature of the reaction tank at 60°C, and end the neutralization gelation reaction after 120 min. After aging treatment at a constant temperature of 85°C and a constant pH value of 8.5 for 5 h, wash with deionized water for 3 times, filter, dry the filter cake at 60°C for 3 h, and then dry at 110°C for 5 h to obtain a boehmite powder.

[0062] (2) Put polyethylene glycol 8000 and ammonium fluoride into cold water at 15°C, then treat under the conditions of stirring at 80 r / min and a temperature of 60°C until complete dissolution, and then treat at 15°C for 4 h to obtain a composite solution containing polyethylene glycol 8000 and fluorine; the amount of polyethylene glycol 8000 added is 6 wt% and the amount of ammonium fluoride (calculated as fluorine) added is 0.6 wt% based on the weight of the alumina carrier (dry basis).

[0063] (3) Take 200 g of the boehmite powder prepared in step (1) (dry basis), 200 g of the composite hydrogel containing polyethylene glycol 8000 and fluorine prepared in step (2), 4 g of sesbania powder and 4 g of citric acid, and mix uniformly to obtain a mixture. Weigh 9.5 g of dilute nitric acid with a concentration of 68 wt% and dilute to 20 mL with deionized water to prepare an acidic solution. Knead the mixture for 15 min, then roll for 20 min, add the acidic solution to the mixture during the rolling process, and appropriately supplement water according to the dryness of the powder during the process. Finally, extrude the mixture into a strip with a three-leaf clover hole plate with a diameter of 1.7 mm, dry at 120°C for 4 h, and then calcine at 600°C for 6 h. The carrier after calcination is denoted as DZ2.

[0064] Example 6

[0065] In this example, the alumina obtained in the above examples and comparative examples is used as a carrier to prepare a hydroprocessing catalyst.

[0066] Take the alumina carrier strips prepared in the examples and comparative examples, immerse in Mo, Ni and P solutions respectively in equal volumes for 2 h, dry at 120°C for 6 h, and calcine at 550°C for 5 h to obtain a hydroprocessing catalyst.

[0067] Table 3 Composition of the catalyst

[0068] Catalyst composition C1 C2 C3 C4 C5 DC1 DC2 MoO3, wt% 20.31 20.28 20.32 20.35 20.30 20.29 20.32 NiO, wt% 3.97 4.01 4.05 4.00 4.03 4.02 4.01

[0069] Example 7

[0070] The catalytic performance evaluation test of the hydroprocessing catalyst: using Iranian VGO as raw material, the properties of the raw oil are shown in Table 4. The activity evaluation of the catalyst was carried out on a small hydrogenation device with a catalyst loading of 100 mL, a reaction temperature of 380°C, a reaction pressure of 14.2 MPa, a volume space velocity of 2.0 h -1 , and a hydrogen / oil volume ratio of 800. The evaluation results of the catalyst prepared in the examples and comparative examples are shown in Table 5.

[0071] Table 4 Properties of raw oil

[0072] Density (20°C), g-cm -3 ]] 0.9052 Distillation range, °C 256～543 S, wt% 1.64 [N, pg g -1 ]]> 1036

[0073] Table 5 Evaluation results

[0074]

[0075] * The relative activity is based on Comparative Example DC-1.

[0076] As can be seen from Table 5, compared with the comparative catalyst, the hydroprocessing catalyst prepared by the support of the application has higher activity, and is particularly suitable for the field of heavy feedstock hydroprocessing.

Claims

1. A process for the preparation of an alumina support, characterized in that: The application comprises the following steps: (1) purchasing or preparing pseudo-boehmite powder; (2) mixing gelatin, fluorine-containing compound and water to prepare a mixed solution, and then solidifying the mixed solution to obtain a composite hydrogel; (3) mixing the pseudo-boehmite powder obtained in step (1) and the composite hydrogel obtained in step (2) uniformly, and then sequentially performing shaping, drying and calcining to obtain an alumina carrier.

2. The method of claim 1, wherein: In step (1), the pseudo-boehmite powder is prepared by mixing an aluminum-containing compound solution and an alkaline precipitant to perform neutralization and gelation reaction, and then filtering and drying the slurry obtained after aging.

3. The method of claim 2, wherein: In step (1), the aluminum-containing compound in the aluminum-containing compound solution is at least one selected from Al2(SO4)3, AlCl3 and Al(NO3)3; the concentration of the aluminum-containing compound solution is not particularly limited, and preferably, the concentration of the aluminum-containing compound solution (calculated as Al2O3) is 20-200 g / L.

4. The method of claim 2, wherein: In step (1), the alkaline precipitant is at least one selected from NaOH, NH4OH and NaAlO2.

5. The method of claim 2, wherein: In step (1), a magnesium-containing additive is introduced into the neutralization and gelation reaction, and preferably, the magnesium-containing additive is mixed with water as a bottom solution, and then the aluminum-containing compound solution and the alkaline precipitant are mixed to perform the neutralization and gelation reaction; the magnesium-containing additive is one or more selected from magnesium sulfate, magnesium nitrate and magnesium chloride; the amount of the magnesium-containing additive (calculated as MgO) is 0.1-5.0 wt%, preferably 0.5-4.5 wt%, based on the weight of the alumina carrier (calculated as the dry weight).

6. The method of claim 2, wherein: In step (1), the neutralization and gelation reaction is performed under the following conditions: pH value is 7-10, temperature is 50-95 ℃, and time is 30-120 min.

7. The method of claim 2, wherein: In step (1), the aging is performed under the following conditions: temperature is 50-90 ℃, pH value is 8-11, and time is 3-24 h; the drying is performed under the following conditions: drying at 50-90 ℃ for 3-10 h, and then drying at 90-250 ℃ for 3-6 h.

8. The method of claim 1, wherein: In step (2), the gelatin is one or more selected from marine gelatin, pig gelatin, cow gelatin and chicken gelatin, and the purity grade is industrial grade or food grade; the molecular weight of the gelatin is 10,000-70,000, preferably 20,000-50,000; the amount of the gelatin is 2-8 wt%, preferably 3-6 wt%, based on the weight of the alumina carrier (calculated as the dry weight).

9. The method of claim 1, wherein: In step (2), the fluorine-containing compound is one or more selected from water-soluble fluorine-containing compounds such as ammonium fluoride, ammonium fluorosilicate, hydrogen fluoride, ammonium bifluoride, calcium fluoride and sodium fluoride, and preferably ammonium fluorosilicate and / or ammonium fluoride; the amount of the fluorine-containing compound (calculated as the elementary substance) is 0.05 wt%-1 wt%, preferably 0.1 wt%-0.6 wt%, based on the weight of the alumina carrier (calculated as the dry weight).

10. The method of claim 1, wherein: In step (2), the specific operation process of mixing the gelatin and the fluorine-containing compound with water is as follows: the gelatin and the fluorine-containing compound are added to water at 5 ℃-20 ℃, and then stirring is performed at 10-140 r / min and the temperature is controlled at 30-70 ℃ until complete dissolution.

11. The method of claim 1, wherein: In step (2), the temperature of the cooling solidification treatment is 2-20°C, and the time is 2-6 hours.

12. The method of claim 1, wherein: In step (3), the mass ratio of the boehmite powder to the composite hydrogel is 0.66-10, preferably 0.8-5.

13. The method of claim 1, wherein: In step (3), the mixing and molding are both carried out at a temperature of 1-30°C, preferably 15-25°C.

14. The method of claim 1, wherein: In step (3), the molding is carried out by any one of drop ball molding, ball granulation, extrusion molding and tablet molding, preferably extrusion molding; the shape of the molding is any one of a ball, a strip and a tablet, preferably any one of a ball and a strip.

15. The method of claim 1, wherein: In step (3), the drying time is 2-10 hours, preferably 3-6 hours, the drying temperature is 80-160°C, preferably 100-130°C; the calcination temperature is 400-700°C, preferably 450-680°C, and the calcination time is 1-10 hours, preferably 2-6 hours.

16. An alumina carrier prepared by the preparation method of any one of claims 1-15.

17. A hydroprocessing catalyst comprising the alumina carrier of claim 16.

18. Use of the hydroprocessing catalyst of claim 17 in a hydroprocessing process.

Images