Hydrodesulfurization and denitrification catalyst as well as preparation method and application thereof

Abstract

The invention provides a hydrodesulfurization and denitrification catalyst and a preparation method and application thereof.The preparation method comprises the steps that manganate and zircon salt are evenly mixed and then dissolved, a phosphoric acid solution is added, and a heteroatom precursor solution is obtained; uniformly mixing and stirring gamma-aluminum oxide and the heteroatom precursor solution, and drying to obtain a heteroatom modified gamma-aluminum oxide precursor; dissolving and uniformly mixing citric acid and nitric acid to obtain an acid solution; uniformly mixing the heteroatom modified gamma-aluminum oxide precursor with sesbania powder, adding an acid solution, and performing rolling, extrusion molding, drying and roasting to obtain a hydrodesulfurization and denitrification catalyst carrier; and preparing a dipping solution from tungsten salt, nickel salt and ethylenediamine tetraacetic acid, dipping the hydrodesulfurization and denitrification catalyst carrier in a saturated dipping manner, drying, and roasting to obtain the hydrodesulfurization and denitrification catalyst. The hydrogenation catalyst obtained by the preparation method provided by the invention not only has relatively high desulfurization and denitrification activity on inferior wax oil, but also has relatively high denitrification activity, and also improves the yield of paraffin.

Description

Technical Field

[0001] The invention relates to a hydrodesulfurization and denitrification catalyst, in particular to a hydrodesulfurization and denitrification catalyst used in the hydrorefining process of inferior wax oil, a preparation method thereof and application of the catalyst in the hydrodesulfurization and denitrification of inferior wax oil, belonging to the technical field of petrochemical catalysts. Background Art

[0002] Inferior wax oil, including wax oil from thermal processing such as coking wax oil and thermal cracking wax oil, is the product of thermal processing of residual oil. It is rich in heavy aromatics, colloids, sulfur and nitrogen, and is difficult to process. At present, some refineries mix it with straight-run wax oil for catalytic cracking processing. However, due to the characteristics of inferior wax oil, it will reduce the activity of catalytic cracking catalyst, reduce the yield and quality of light oil, increase the coking rate, and reduce the processing capacity of catalytic cracking unit.

[0003] Chinese patent CN108452844A provides a method of 2 O 3 -(ETS-10)-TiO 2 -La 2 O 3 - A hydrogenation catalyst with graphene composite oxide as a carrier and Ni and Mo as active metal components. However, the catalyst has the disadvantages of complex carrier structure and high cost.

[0004] Chinese patent CN105749925A discloses a heavy oil hydrogenation catalyst using hydrothermally treated silicon or fluorine-containing alumina as a carrier and molybdenum, nickel and cobalt as active metals. However, this method has the disadvantages of complex operation and high cost.

[0005] Chinese patent CN111558377A provides a C12A7-O 2- -C12A7-H--C12A7-e - -A l 2 O 3 Hydrodesulfurization and denitrification catalysts with composite oxides as carriers. However, the catalysts have a complex structure and are difficult to apply in industry.

[0006] Chinese patent CN111298800A discloses a hydrodesulfurization catalyst, comprising a heteroatom-modified γ-alumina carrier and an active component, wherein the heteroatom-modified γ-alumina carrier is composed of heteroatom oxides and γ-alumina, and the heteroatom can be manganese, iron, cobalt, gallium, niobium, rhenium and lanthanide elements. However, the catalyst can only be used in the desulfurization process, and it is not shown that it can be used for denitrification and improving the yield of paraffins. The desulfurization rate of the catalyst is only 87% at most, the desulfurization rate is low, and the catalyst selectivity is poor; in addition, the catalyst is only suitable for diesel hydrodesulfurization, and the dry point of the diesel feedstock is ≯350°C, and is not suitable for wax oil fractions with a dry point of ≯520°C.

[0007] In summary, the current hydrodesulfurization and denitrification catalysts using various modified aluminas as carriers still have shortcomings such as harsh preparation conditions, complex preparation methods, and low hydrodesulfurization activity. Therefore, developing a hydrogenation catalyst with a simple preparation method and good hydrodesulfurization effect has become the focus of current research. Summary of the invention

[0008] The object of the present invention is to provide a method for preparing a hydrodesulfurization and denitrification catalyst. The hydrodesulfurization and denitrification catalyst obtained by the preparation method can simultaneously improve the desulfurization rate, denitrification activity and the yield of paraffins, and can be used in the hydrorefining process of inferior wax oil.

[0009] The invention discloses a method for preparing a hydrodesulfurization and denitrification catalyst, which comprises the following steps:

[0010] (1) After the manganate and the zirconium salt are uniformly mixed, they are dissolved and a phosphoric acid solution is added to obtain a heteroatom precursor solution, wherein the mass ratio of the manganate, the zirconium salt and the phosphoric acid added is MnO:ZrO based on the corresponding oxides. 2 :P 2 O 5 =60wt%: (20-30)wt%: (10-20)wt%;

[0011] (2) mixing the γ-alumina and the heteroatom precursor solution, stirring them uniformly, and drying them to obtain a heteroatom-modified γ-alumina precursor;

[0012] (3) dissolving citric acid and nitric acid and mixing them uniformly to obtain an acid solution, wherein the amount of citric acid and nitric acid added is 6-9wt% and 3-5wt% of the mass of the hydrodesulfurization and denitrification catalyst carrier;

[0013] (4) uniformly mixing the heteroatom-modified γ-alumina precursor and the sesbania powder, adding the acid solution prepared in step (3), rolling, extruding, drying, and calcining to obtain a hydrodesulfurization and denitrification catalyst carrier;

[0014] (5) Tungsten salt, nickel salt and ethylenediaminetetraacetic acid are prepared into an impregnation solution, and the solution is impregnated into a hydrodesulfurization and denitrification catalyst carrier, and then dried and calcined to obtain a hydrodesulfurization and denitrification catalyst.

[0015] In the preparation method of the hydrodesulfurization and denitrification catalyst of the present invention, the manganate is at least one of potassium permanganate, manganese sulfate and manganese nitrate; and the zirconium salt is at least one of zirconium oxychloride, zirconium tetrachloride and zirconium n-propoxide.

[0016] In the method for preparing the hydrodesulfurization and denitrification catalyst of the present invention, in step (2), the heteroatom-modified γ-alumina precursor is composed of 11-20 wt% of heteroatom precursor oxide and 80-89 wt% of γ-alumina.

[0017] In the method for preparing a hydrodesulfurization and denitrification catalyst of the present invention, in step (4), the atomic modified γ-alumina precursor accounts for 92-95wt% of the mass of the hydrodesulfurization and denitrification catalyst carrier, and the sesbania powder accounts for 5%-8% of the mass of the hydrodesulfurization and denitrification catalyst carrier.

[0018] The preparation method of the hydrodesulfurization and denitrification catalyst of the present invention, in step (5), in the impregnation solution, the amount of nickel salt added is 2-10wt% of the mass of the hydrodesulfurization and denitrification catalyst in terms of NiO, and the amount of tungsten salt added is 10wt% of the mass of the hydrodesulfurization and denitrification catalyst in terms of WO 3 The amount of ethylenediaminetetraacetic acid added accounts for 20-28wt% of the mass of the hydrodesulfurization and denitrification catalyst, and the amount of ethylenediaminetetraacetic acid added accounts for 2-8wt% of the mass of the hydrodesulfurization and denitrification catalyst.

[0019] The method for preparing the hydrodesulfurization and denitrification catalyst of the present invention has a specific surface area of ​​180-350m 2 / g, pore volume is 0.4-0.8cm 3 / g, the average pore size is 6-10nm, and the particle size is 20-40 mesh.

[0020] In the preparation method of the hydrodesulfurization and denitrification catalyst of the present invention, in step (5), the impregnation time is 1-2 hours; the drying temperature is 100-120° C., and the time is 2-4 hours; the calcination temperature is 500-600° C., and the time is 3-6 hours.

[0021] The present invention also provides a hydrodesulfurization and denitrification catalyst obtained by the above preparation method.

[0022] The present invention further provides an application of the hydrodesulfurization and denitrification catalyst obtained by the above preparation method in the hydrorefining process of inferior Russian wax oil.

[0023] In the application of the present invention, the reaction conditions of the hydrofining process are: reaction temperature of 320-400°C, hydrogen partial pressure of 10-17MPa, hydrogen-oil volume ratio of 500-1000:1, liquid hourly space velocity of 1.5-2.5h -1 .

[0024] The invention discloses a method for preparing a hydrodesulfurization and denitrification catalyst. After gamma-alumina is modified by a composite heteroatom precursor solution, the modification by P can improve the acidity of the hydrodesulfurization and denitrification catalyst carrier. The heteroatom precursor solution prepared by composite heteroatom manganese, zirconium and an organic complexing solvent is more conducive to the interaction between gamma-alumina and active metals, improves the stacking layer number and sulfurization degree of the active phase, improves the dispersion, and obtains a carrier with good pore properties and suitable acid distribution. The prepared hydrodesulfurization and denitrification catalyst can simultaneously improve the hydrodesulfurization and denitrification activities and the paraffin yield in the hydrorefining of inferior wax oil, the desulfurization rate is ≮98%, the denitrification rate is ≮99%, and the paraffin yield is increased by at least 6%, and is suitable for the hydrorefining process of heavier fraction oil. DETAILED DESCRIPTION

[0025] In order to have a clearer understanding of the purpose, technical solutions and beneficial effects of the present invention, the technical solutions in the present invention are now described in detail and completely as follows, but this should not be considered as limiting the scope of implementation of the present invention.

[0026] Example 1

[0027] (1) 7.3 g of potassium permanganate and 3.1 g of zirconium tetrachloride were added to 30 g of deionized water and dissolved and mixed evenly, and 0.76 g of phosphoric acid was gradually added dropwise. After being fully stirred, a heteroatom precursor solution A1 was obtained.

[0028] (2) 44.5 g of γ-alumina and the heteroatom precursor solution A1 were impregnated in equal volumes, mixed and stirred evenly, and then dried at 120° C. for 2 h to obtain a heteroatom-modified γ-alumina precursor.

[0029] (3) Add 3 g of citric acid and 1.5 g of nitric acid to 45 g of deionized water, dissolve and mix evenly to prepare acid solution B1.

[0030] (4) 47.5 g of heteroatom-modified γ-alumina precursor and 2.5 g of sesbania powder were mixed evenly, and the acid solution B1 prepared in step (3) was added dropwise, and the mixture was rolled into blocks, extruded into strips, dried at 120° C. for 2 h, and calcined at 550° C. for 4 h to obtain a hydrodesulfurization and denitrification catalyst carrier.

[0031] (5) The water absorption rate of the hydrodesulfurization and denitrification catalyst carrier was measured to be 62%. 67.3 g of ammonium metatungstate, 53.4 g of nickel nitrate, and 2 g of ethylenediaminetetraacetic acid were added to a beaker filled with deionized water to dissolve and prepare 100 mL of impregnation solution. 67 g of the hydrodesulfurization and denitrification catalyst carrier was taken and the impregnation solution was added to the carrier by an equal volume impregnation method. The carrier was impregnated for 2 h, dried at 120 ° C for 4 h, and calcined at 500 ° C in air atmosphere for 4 h to obtain the hydrodesulfurization and denitrification catalyst C1.

[0032] Example 2

[0033] (1) 8.3 g of manganese nitrate and 2.4 g of zirconium oxychloride were added to 30 g of deionized water and dissolved and mixed evenly, and 0.76 g of phosphoric acid was gradually added dropwise. After being fully stirred, a heteroatom precursor solution A2 was obtained.

[0034] (2) 44.5 g of γ-alumina and heteroatom precursor solution A2 were impregnated in equal volumes, mixed and stirred evenly, and dried at 120° C. for 2 h to obtain a heteroatom-modified γ-alumina precursor.

[0035] (3) Add 3 g of citric acid and 1.5 g of nitric acid to 45 g of deionized water, dissolve and mix evenly to prepare acid solution B2.

[0036] (4) 47.5 g of heteroatom-modified γ-alumina precursor and 2.5 g of sesbania powder were mixed evenly, and the acid solution B2 prepared in step (3) was added dropwise, and the mixture was rolled into blocks, extruded into strips, dried at 120° C. for 2 h, and calcined at 550° C. for 4 h to obtain a hydrodesulfurization and denitrification catalyst carrier.

[0037] (5) The water absorption rate of the hydrodesulfurization and denitrification catalyst carrier was measured to be 62%. 67.3 g of ammonium metatungstate, 53.4 g of nickel nitrate, and 2 g of ethylenediaminetetraacetic acid were added to a beaker filled with deionized water to dissolve and prepare 100 mL of impregnation solution. 67 g of the hydrodesulfurization and denitrification catalyst carrier was taken and the impregnation solution was added to the carrier by an equal volume impregnation method. The carrier was impregnated for 2 h, dried at 120 ° C for 4 h, and calcined at 500 ° C in air atmosphere for 4 h to obtain the hydrodesulfurization and denitrification catalyst C2.

[0038] Example 3

[0039] (1) 7.85 g of manganese sulfate monohydrate and 2.4 g of zirconium oxychloride were added to 30 g of deionized water and dissolved and mixed evenly, and 0.76 g of phosphoric acid was gradually added dropwise. After being fully stirred, a heteroatom precursor solution A3 was obtained.

[0040] (2) 44.5 g of γ-alumina and the heteroatom precursor solution A3 were impregnated in equal volumes, mixed and stirred evenly, and dried at 120° C. for 2 h to obtain a heteroatom-modified γ-alumina precursor.

[0041] (3) Add 3 g of citric acid and 1.5 g of nitric acid to 45 g of deionized water, dissolve and mix evenly to prepare acid solution B3.

[0042] (4) 47.5 g of heteroatom-modified γ-alumina precursor and 2.5 g of sesbania powder were mixed evenly, and the acid solution B3 prepared in step (3) was added dropwise, and the mixture was rolled into blocks, extruded into strips, dried at 120° C. for 2 h, and calcined at 550° C. for 4 h to obtain a hydrodesulfurization and denitrification catalyst carrier.

[0043] (5) The water absorption rate of the hydrodesulfurization and denitrification catalyst carrier was measured to be 62%. 67.3 g of ammonium metatungstate, 53.4 g of nickel nitrate, and 2 g of ethylenediaminetetraacetic acid were added to a beaker filled with deionized water to dissolve and prepare 100 mL of impregnation solution. 67 g of the hydrodesulfurization and denitrification catalyst carrier was taken and the impregnation solution was added to the carrier by equal volume impregnation. The carrier was impregnated for 2 h, dried at 120 ° C for 4 h, and calcined at 500 ° C in air atmosphere for 4 h to obtain the hydrodesulfurization and denitrification catalyst C3.

[0044] Example 4

[0045] (1) 7.3 g of potassium permanganate and 2.1 g of zirconium tetrachloride were added to 30 g of deionized water and dissolved and mixed evenly, and 1.52 g of phosphoric acid was gradually added dropwise. After being fully stirred, a heteroatom precursor solution A4 was obtained.

[0046] (2) 44.5 g of γ-alumina and heteroatom precursor solution A4 were impregnated in equal volumes, mixed and stirred evenly, and dried at 120° C. for 2 h to obtain a heteroatom-modified γ-alumina precursor.

[0047] (3) Add 3 g of citric acid and 1.5 g of nitric acid to 45 g of deionized water, dissolve and mix evenly to prepare acid solution B4.

[0048] (4) 47.5 g of heteroatom-modified γ-alumina precursor and 2.5 g of sesbania powder were mixed evenly, and the acid solution B4 prepared in step (3) was added dropwise, and the mixture was rolled into blocks, extruded into strips, dried at 120° C. for 2 h, and calcined at 550° C. for 4 h to obtain a hydrodesulfurization and denitrification catalyst carrier.

[0049] (5) The water absorption rate of the hydrodesulfurization and denitrification catalyst carrier was measured to be 62%. 67.3 g of ammonium metatungstate, 53.4 g of nickel nitrate, and 2 g of ethylenediaminetetraacetic acid were added to a beaker filled with deionized water to dissolve and prepare 100 mL of impregnation solution. 67 g of the hydrodesulfurization and denitrification catalyst carrier was taken and the impregnation solution was added to the carrier by equal volume impregnation. The carrier was impregnated for 2 h, dried at 120 ° C for 4 h, and calcined at 500 ° C in air atmosphere for 4 h to obtain the hydrodesulfurization and denitrification catalyst C4.

[0050] Example 5

[0051] (1) 7.3 g of potassium permanganate and 2.6 g of zirconium tetrachloride were added to 30 g of deionized water and dissolved and mixed evenly, and 1.14 g of phosphoric acid was gradually added dropwise. After being fully stirred, a heteroatom precursor solution A5 was obtained.

[0052] (2) 44.5 g of γ-alumina and the heteroatom precursor solution A5 were impregnated in equal volumes, mixed and stirred evenly, and then dried at 120° C. for 2 h to obtain a heteroatom-modified γ-alumina precursor.

[0053] (3) Add 3 g of citric acid and 1.5 g of nitric acid to 45 g of deionized water, dissolve and mix evenly to prepare acid solution B5.

[0054] (4) 47.5 g of heteroatom-modified γ-alumina precursor and 2.5 g of sesbania powder were mixed evenly, and the acid solution B5 prepared in step (3) was added dropwise, and the mixture was rolled into blocks, extruded into strips, dried at 120° C. for 2 h, and calcined at 550° C. for 4 h to obtain a hydrodesulfurization and denitrification catalyst carrier.

[0055] (5) The water absorption rate of the hydrodesulfurization and denitrification catalyst carrier was measured to be 62%. 67.3 g of ammonium metatungstate, 53.4 g of nickel nitrate, and 2 g of ethylenediaminetetraacetic acid were added to a beaker filled with deionized water to dissolve and prepare 100 mL of impregnation solution. 67 g of the hydrodesulfurization and denitrification catalyst carrier was taken and the impregnation solution was added to the carrier by an equal volume impregnation method. The carrier was impregnated for 2 h, dried at 120 ° C for 4 h, and calcined at 500 ° C in air atmosphere for 4 h to obtain the hydrodesulfurization and denitrification catalyst C5.

[0056] Example 6

[0057] (1) 13.4 g of potassium permanganate and 5.7 g of zirconium tetrachloride were added to 30 g of deionized water and dissolved and mixed evenly, and 1.38 g of phosphoric acid was gradually added dropwise. After being fully stirred, a heteroatom precursor solution A6 was obtained.

[0058] (2) 40 g of γ-alumina and the heteroatom precursor solution A6 were impregnated in equal volumes, mixed and stirred evenly, and then dried at 120° C. for 2 h to obtain a heteroatom-modified γ-alumina precursor.

[0059] (3) Add 3 g of citric acid and 1.5 g of nitric acid to 45 g of deionized water, dissolve and mix evenly to prepare acid solution B6.

[0060] (4) 47.5 g of heteroatom-modified γ-alumina precursor and 2.5 g of sesbania powder were mixed evenly, and the acid solution B6 prepared in step (3) was added dropwise, and the mixture was rolled into blocks, extruded into strips, dried at 120° C. for 2 h, and calcined at 550° C. for 4 h to obtain a hydrodesulfurization and denitrification catalyst carrier.

[0061] (5) The water absorption rate of the hydrodesulfurization and denitrification catalyst carrier was measured to be 62%. 45.6 g of ammonium metatungstate, 16.4 g of nickel nitrate, and 2 g of ethylenediaminetetraacetic acid were added to a beaker filled with deionized water to dissolve and prepare 100 mL of impregnation solution. 78 g of the hydrodesulfurization and denitrification catalyst carrier was taken and the impregnation solution was added to the carrier by equal volume impregnation. The carrier was impregnated for 2 h, dried at 120 ° C for 4 h, and calcined at 500 ° C in air atmosphere for 4 h to obtain the hydrodesulfurization and denitrification catalyst C6.

[0062] Example 7

[0063] (1) 7.3 g of potassium permanganate and 3.1 g of zirconium tetrachloride were added to 30 g of deionized water and dissolved and mixed evenly, and 0.76 g of phosphoric acid was gradually added dropwise. After being fully stirred, a heteroatom precursor solution A7 was obtained.

[0064] (2) 44.5 g of γ-alumina and the heteroatom precursor solution A7 were impregnated in equal volumes, mixed and stirred evenly, and dried at 120° C. for 2 h to obtain a heteroatom-modified γ-alumina precursor.

[0065] (3) Add 4.5 g of citric acid and 2.5 g of nitric acid to 45 g of deionized water, dissolve and mix well to prepare acid solution B7.

[0066] (4) 47.5 g of heteroatom-modified γ-alumina precursor and 2.5 g of sesbania powder were mixed evenly, and the acid solution B7 prepared in step (3) was added dropwise, and the mixture was rolled into blocks, extruded into strips, dried at 120° C. for 2 h, and calcined at 550° C. for 4 h to obtain a hydrodesulfurization and denitrification catalyst carrier.

[0067] (5) The water absorption rate of the hydrodesulfurization and denitrification catalyst carrier was measured to be 62%. 80.3 g of ammonium metatungstate, 102.4 g of nickel nitrate, and 8 g of ethylenediaminetetraacetic acid were added to a beaker filled with deionized water to dissolve and prepare 100 mL of impregnation solution. 39 g of the hydrodesulfurization and denitrification catalyst carrier was taken and the impregnation solution was added to the carrier by equal volume impregnation. The catalyst was impregnated for 2 h, dried at 120 ° C for 4 h, and calcined at 500 ° C in air atmosphere for 4 h to obtain the hydrodesulfurization and denitrification catalyst C7.

[0068] Example 8

[0069] (1) 7.3 g of potassium permanganate and 2.6 g of zirconium tetrachloride were added to 30 g of deionized water and dissolved and mixed evenly, and 1.14 g of phosphoric acid was gradually added dropwise. After being fully stirred, a heteroatom precursor solution A8 was obtained.

[0070] (2) 44.5 g of γ-alumina and heteroatom precursor solution A8 were impregnated in equal volumes, mixed and stirred evenly, and dried at 120° C. for 2 h to obtain a heteroatom-modified γ-alumina precursor.

[0071] (3) Add 3 g of citric acid and 1.5 g of nitric acid to 45 g of deionized water, dissolve and mix well to prepare acid solution B8.

[0072] (4) 47.5 g of heteroatom-modified γ-alumina precursor and 2.5 g of sesbania powder were mixed evenly, and the acid solution B8 prepared in step (3) was added dropwise, and the mixture was rolled into blocks, extruded into strips, dried at 120° C. for 2 h, and calcined at 550° C. for 4 h to obtain a hydrodesulfurization and denitrification catalyst carrier.

[0073] (5) The water absorption rate of the hydrodesulfurization and denitrification catalyst carrier was measured to be 62%. 45.6 g of ammonium metatungstate, 16.4 g of nickel nitrate, and 2 g of ethylenediaminetetraacetic acid were added to a beaker filled with deionized water to dissolve and prepare 100 mL of impregnation solution. 78 g of the hydrodesulfurization and denitrification catalyst carrier was taken and the impregnation solution was added to the carrier by equal volume impregnation. The catalyst was impregnated for 2 h, dried at 120 ° C for 4 h, and calcined at 500 ° C in air atmosphere for 4 h to obtain the hydrodesulfurization and denitrification catalyst C8.

[0074] Comparative Example 1

[0075] The difference from Example 1 is that a γ-alumina carrier is used.

[0076] (1) Dissolve 67.7 g aluminum nitrate in 180 mL deionized water and stir until clear to obtain 1 mol·L -1 Aluminum nitrate solution; take appropriate amount of ammonia water and deionized water in a volume ratio of 1:1 to mix and dilute; add diluted ammonia water dropwise to the aluminum nitrate solution at a water bath temperature of 50°C and under continuous stirring until the pH of the system is 10, and continue stirring for 10 minutes; the obtained aluminum hydroxide suspension is placed at room temperature for aging for 3 hours, and then filtered until the supernatant and the liquid dripping from the bottom of the funnel have a pH of 7; the obtained filter cake is placed in an oven at 100°C for 12 hours and calcined at 550°C for 4 hours to obtain a γ-alumina carrier, and the γ-alumina carrier is pressed into tablets at 30MPa and sieved to form particles of 20-40 mesh.

[0077] (2) Weigh 67g of the above-mentioned γ-alumina carrier and determine its water absorption rate to be 62%. Then weigh 67.3g of ammonium metatungstate, 53.4g of nickel nitrate and 2g of ethylenediaminetetraacetic acid and add them to a beaker filled with deionized water to dissolve and prepare 100mL of impregnation solution. Take 67g of the γ-alumina carrier and add the above-mentioned impregnation solution to the carrier by equal volume impregnation. Impregnate for 2h, dry at 120℃ for 4h, and calcine at 500℃ in air atmosphere for 4h to obtain a hydrogenation catalyst with γ-alumina as the carrier, named A1.

[0078] Comparative Example 2

[0079] The difference from Example 1 is that zirconium-aluminum composite oxide is used as the catalyst carrier.

[0080] (1) Dissolve 67.7 g aluminum nitrate in 180 mL deionized water and stir until clear to obtain 1 mol·L -1 Aluminum nitrate solution was prepared by dissolving 2.09 g zirconium oxychloride in 13 mL deionized water and stirring until clear to obtain 0.5 mol·L -1 zirconium oxychloride solution, mix the two evenly to obtain a zirconium-aluminum mixed solution; take appropriate amounts of ammonia water and deionized water and mix and dilute them in a volume ratio of 1:1; add diluted ammonia water dropwise to the zirconium-aluminum mixed solution at a water bath temperature of 50°C and continuous stirring until the pH value of the system is 10, and continue stirring for 10 minutes; the obtained composite hydroxide suspension is placed at room temperature for aging for 3 hours, and then filtered until the supernatant and the liquid dripping from the bottom of the funnel have a pH value of 7; the obtained filter cake is placed in an oven at 100°C and dried for 12 hours, and calcined at 550°C for 4 hours to obtain a zirconium-aluminum composite oxide carrier with a zirconium oxide content of 8wt%, and the zirconium-aluminum composite oxide is extruded into strips, dried at 120°C for 2 hours, and calcined at 550°C for 4 hours to obtain a hydrodesulfurization and denitrification catalyst carrier.

[0081] (2) The water absorption rate of the hydrodesulfurization and denitrification catalyst carrier was measured to be 62%. 67.3 g of ammonium metatungstate, 53.4 g of nickel nitrate, and 2 g of ethylenediaminetetraacetic acid were added to a beaker filled with deionized water to dissolve and prepare 100 mL of impregnation solution. 67 g of the hydrodesulfurization and denitrification catalyst carrier was taken and the impregnation solution was added to the carrier by an equal volume impregnation method. The carrier was impregnated for 2 h, dried at 120 ° C for 4 h, and calcined at 500 ° C in air atmosphere for 4 h to obtain the hydrodesulfurization and denitrification catalyst A2.

[0082] Comparative Example 3

[0083] The difference from Example 1 is that phosphoric acid is not added during the preparation of the heteroatom precursor solution.

[0084] (1) 7.3 g of potassium permanganate and 3.1 g of zirconium tetrachloride were added into 30 g of deionized water and dissolved and mixed evenly to obtain a heteroatom precursor solution DA1.

[0085] (2) 44.5 g of γ-alumina and the heteroatom precursor solution DA1 were impregnated in equal volumes, mixed and stirred evenly, and then dried at 120° C. for 2 h to obtain a heteroatom-modified γ-alumina precursor.

[0086] (3) Add 3 g of citric acid and 1.5 g of nitric acid to 45 g of deionized water, dissolve and mix evenly to prepare an acid solution DB1.

[0087] (4) 47.5 g of heteroatom-modified γ-alumina precursor and 2.5 g of sesbania powder were mixed evenly, and the acid solution DB1 prepared in step (3) was added dropwise, and the mixture was rolled into blocks, extruded into strips, dried at 120° C. for 2 h, and calcined at 550° C. for 4 h to obtain a hydrodesulfurization and denitrification catalyst carrier.

[0088] (5) The water absorption rate of the hydrodesulfurization and denitrification catalyst carrier was measured to be 62%. 67.3 g of ammonium metatungstate, 53.4 g of nickel nitrate, and 2 g of ethylenediaminetetraacetic acid were added to a beaker filled with deionized water to dissolve and prepare 100 mL of impregnation solution. 67 g of the hydrodesulfurization and denitrification catalyst carrier was taken and the impregnation solution was added to the carrier by an equal volume impregnation method. The carrier was impregnated for 2 h, dried at 120 ° C for 4 h, and calcined at 500 ° C in air atmosphere for 4 h to obtain the hydrodesulfurization and denitrification catalyst A3.

[0089] Comparative Example 4

[0090] The difference from Example 1 is that the γ-alumina is modified with manganese and zirconium heteroatoms, and the heteroatom-modified γ-alumina precursor consists of 5 wt % of heteroatom precursor oxide and 95 wt % of γ-alumina.

[0091] (1) 3.34 g of potassium permanganate and 1.9 g of zirconium tetrachloride were added to 30 g of deionized water and dissolved and mixed evenly, and 0.76 g of phosphoric acid was gradually added dropwise. After being fully stirred, a heteroatom precursor solution DA2 was obtained.

[0092] (2) 47.5 g of γ-alumina and the heteroatom precursor solution DA2 were impregnated in equal volumes, mixed and stirred evenly, and dried at 120° C. for 2 h to obtain a heteroatom-modified γ-alumina precursor.

[0093] (3) Add 3 g of citric acid and 1.5 g of nitric acid to 45 g of deionized water, dissolve and mix evenly to prepare acid solution DB2.

[0094] (4) 47.5 g of heteroatom-modified γ-alumina precursor and 2.5 g of sesbania powder were mixed evenly, and the acid solution DB2 prepared in step (3) was added dropwise, and the mixture was rolled into blocks, extruded into strips, dried at 120° C. for 2 h, and calcined at 550° C. for 4 h to obtain a hydrodesulfurization and denitrification catalyst carrier.

[0095] (5) The water absorption rate of the hydrodesulfurization and denitrification catalyst carrier was measured to be 62%. 67.3 g of ammonium metatungstate, 53.4 g of nickel nitrate, and 2 g of ethylenediaminetetraacetic acid were added to a beaker filled with deionized water to dissolve and prepare 100 mL of impregnation solution. 67 g of the hydrodesulfurization and denitrification catalyst carrier was taken and the impregnation solution was added to the carrier by an equal volume impregnation method. The carrier was impregnated for 2 h, dried at 120 ° C for 4 h, and calcined at 500 ° C in air atmosphere for 4 h to obtain the hydrodesulfurization and denitrification catalyst A4.

[0096] Example 9

[0097] This example provides a comparative experiment on the hydrorefining performance of catalysts for inferior wax oil.

[0098] The catalysts in Examples 1-8 and Comparative Examples 1-4 were used to conduct a hydrorefining experiment on low-quality wax oil; the raw materials used in the experiment were wax oil fractions with a dry point of ≯520°C from a refinery, a sulfur content of ≮3000μg / g, and a nitrogen content of ≮1500μg / g.

[0099] The reaction conditions for evaluating the catalyst's performance in hydrorefining of inferior wax oil were: reaction temperature of 375°C, hydrogen partial pressure of 15 MPa, hydrogen-oil volume ratio of 1000:1, and space velocity of 1.5 h -1 .

[0100] The catalyst properties and the experimental evaluation results of the catalyst's performance on the hydrorefining of inferior wax oil are shown in Table 1.

[0101] Table 1

[0102]

[0103]

[0104] The results of Table 1 show that compared with the unmodified catalyst, the hydrodesulfurization and denitrification catalyst modified with manganese, zirconium and phosphorus composite heteroatoms of the present invention shows higher hydrogenation activity for inferior wax oil. When γ-alumina is modified by different modification methods, the catalyst shows different hydrorefining activities for inferior wax oil, which is mainly determined by the mixing level of composite heteroatoms manganese, zirconium, phosphorus atoms and aluminum. When phosphoric acid is not added or the content of heteroatom precursor oxide is reduced, the desulfurization, denitrification and paraffin yield of the catalyst are significantly reduced. The heteroatom precursor solution prepared by the present invention using composite heteroatoms manganese, zirconium and phosphoric acid is more conducive to the interaction between γ-alumina and active metals tungsten and nickel, increases the number of stacking layers and the degree of sulfidation of the active phase, and simultaneously increases the denitrification rate and paraffin yield, the desulfurization rate ≮98%, the denitrification rate ≮99%, and the paraffin yield is increased by at least 6%.

[0105] The hydrodesulfurization and denitrification catalyst using heteroatom-modified γ-alumina as a carrier and the preparation method thereof are suitable for the hydroprocessing process of inferior wax oil, and show excellent performance in the hydrodesulfurization and denitrification of inferior wax oil and improving the paraffin yield.

[0106] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, technicians familiar with the field may make various corresponding changes and deformations based on the present invention, but these corresponding changes and deformations should all fall within the scope of protection of the claims of the present invention.

Claims

1. A preparation method of a hydrodesulfurization and denitrification catalyst, characterized in that, it comprises the following steps: (1) After uniformly mixing the manganate and zirconium salt, dissolving them, and adding a phosphoric acid solution, a heteroatom precursor solution is obtained. Among them, the mass ratio of the manganate, zirconium salt, and phosphoric acid added, calculated based on the corresponding oxides, is MnO:ZrO 2 :P 2 O 5 = 60 wt%:(20 - 30) wt%:(10 - 20) wt%; (2) Mix γ-alumina with a heteroatom precursor solution and stir evenly, then dry to obtain a heteroatom-modified γ-alumina precursor; (3) Dissolve and mix citric acid and nitric acid evenly to obtain an acid solution, wherein the addition amounts of citric acid and nitric acid are 6-9 wt% and 3-5 wt% of the mass of the hydrodesulfurization and denitrification catalyst support; (4) Mix the heteroatom-modified γ-alumina precursor with sesbania powder evenly, add the acid solution prepared in step (3), roll, extrude into strips, dry, and calcine to obtain a hydrodesulfurization and denitrification catalyst support; (5) Prepare an impregnation solution from a tungsten salt, a nickel salt, and ethylenediaminetetraacetic acid, impregnate the hydrodesulfurization and denitrification catalyst support, dry, and calcine to obtain a hydrodesulfurization and denitrification catalyst.

2. The preparation method of the hydrodesulfurization and denitrification catalyst according to claim 1, characterized in that, the manganate is at least one of potassium permanganate, manganese sulfate, and manganese nitrate; the zirconium salt is at least one of zirconium oxychloride, zirconium tetrachloride, and zirconium n-propoxide.

3. The preparation method of the hydrodesulfurization and denitrification catalyst according to claim 1, characterized in that, in step (2), the heteroatom-modified γ-alumina precursor is composed of 11-20 wt% of heteroatom precursor oxide and 80-89 wt% of γ-alumina.

4. The preparation method of the hydrodesulfurization and denitrification catalyst according to claim 1, characterized in that, in step (4), the atom-modified γ-alumina precursor accounts for 92-95 wt% of the mass of the hydrodesulfurization and denitrification catalyst support, and the sesbania powder accounts for 5%-8% of the mass of the hydrodesulfurization and denitrification catalyst support.

5. The preparation method of the hydrodesulfurization and denitrification catalyst according to claim 1, characterized in that, In step (5), in the impregnation solution, the addition amount of nickel salt, calculated as NiO, accounts for 2-10 wt% of the mass of the hydrodesulfurization and denitrification catalyst, and the addition amount of tungsten salt, calculated as WO 3 3, accounts for 20-28 wt% of the mass of the hydrodesulfurization and denitrification catalyst, and the addition amount of ethylenediaminetetraacetic acid accounts for 2-8 wt% of the mass of the hydrodesulfurization and denitrification catalyst.

6. The preparation method of the hydrodesulfurization and denitrification catalyst according to claim 1, characterized in that, The specific surface area of the hydrodesulfurization and denitrification catalyst is 180 - 350 m 2 / g, the pore volume is 0.4 - 0.8 cm 3 / g, the average pore diameter is 6 - 10 nm, and the particle size is 20 - 40 mesh.

7. The preparation method of the hydrodesulfurization and denitrification catalyst according to claim 1, characterized in that, in step (5), the impregnation time is 1-2 h; the drying temperature is 100-120 °C and the time is 2-4 h; the calcination temperature is 500-600 °C and the time is 3-6 h.

8. A hydrodesulfurization and denitrification catalyst obtained by the preparation method according to any one of claims 1-7.

9. An application of a hydrodesulfurization and denitrification catalyst obtained by the preparation method according to any one of claims 1-7 in the hydrorefining process of inferior Russian wax oil.

10. The application according to claim 9, characterized in that, The reaction conditions of the hydrofining process are as follows: the reaction temperature is 320 - 400 °C, the hydrogen partial pressure is 10 - 17 MPa, the hydrogen-oil volume ratio is 500 - 1000:1, and the liquid hourly space velocity is 1.5 - 2.5 h -1 .

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