NL8001993A - HYDROGENATION CATALYST AND METHOD FOR PREPARING THE SAME, AND METHOD FOR HYDROGENATING TREATMENT OF HYDROCARBON MATERIALS. - Google Patents

Description

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Hydrogenation catalyst and process for its preparation, as well as process for hydrotreating hydrocarbon materials.

The invention relates to an improved catalyst suitable for the hydrotreating of hydrocarbon materials, which catalyst contains a Group VIB metal of the Periodic Table of the Elements and a metal of Group VIII of the Periodic System of the 5 Elements and a carrier, and to methods of preparing this catalyst.

Hydrogenation treatments include hydrodesulfuration, hydrodenitrogenation and demetallation of hydrocarbon materials. The invention is particularly directed to the preparation of a catalytic composition having superior hydrogenation activity in the removal of sulfur and nitrogen from heavy hydrocarbon materials. Examples of these heavy materials are whole crude oil, crude residue, gas oil obtained at atmospheric pressure, gas oil obtained under reduced pressure and recycled oil.

Crude oil and heavy hydrocarbon fractions and / or distillates obtained from raw materials contain components such as nitrogen, sulfur and metals. These impurities can exist as hetero atoms in compounds and are often present in relatively large amounts. The impurities can poison or modify catalysts used to improve the quality of petroleum fractions in reforming or cracking operations. Nitrogen and sulfur are also objectionable because combustion of hydrocarbon fuels containing these impurities releases nitrogen and sulfur oxides. These gases formed as by-products are harmful and corrosive and lead to serious air pollution problems.

The removal and / or conversion of these impurities is expediently accomplished by catalytic hydrotreating, wherein a sulfur and nitrogen-containing feedstock is contacted with a support-containing catalyst in the presence of hydrogen. The hydrogenation conditions can span a wide range of temperatures, pressures and volume rates determined by commercial refineries.

Supported catalysts generally contain metals and as support a heat-resistant inorganic oxide of synthetic or natural origin with a moderate to high specific surface area and a well-developed pore structure. Metals with hydrogenation activity present as components in these catalysts may include the metals of the 8001993 4 r - 2 - r groups VIB and VIII of the Periodic System of the Elements.

Methods for preparing support-containing catalysts for hydrogenation treatments have been described in numerous references. Catalytic metals can be applied to a molded or non-molded support by various known impregnation methods. This is usually followed by a shaping operation (if necessary) and by calcination to convert the compounds of the catalytic metals into oxides.

Several methods have been proposed for preparing active hydrogenation catalysts by a single impregnation method using acid-stabilized solutions of the catalytically active metals.

US patent 3,232,887 describes a method for impregnating catalyst supports, wherein the metal-containing impregnation solution is stabilized with an acidic compound. The acidic stabilizer can be organic (e.g. gluconic or citric acid) or inorganic. The preferred acid is phosphoric acid. The acid stabilized solution contains Group VIB and VIII metals, in the case of phosphoric acid the molar ratio of phosphorus to Group VIB metal (eg P / Mo) ranges from 0.25: 1 to 2.5: 1.

U.S. Patent 3,287,280 describes a process for preparing a hydrodesulfurization catalyst by impregnating a formed aluminum oxide support with a phosphoric acid stabilized solution of molybdenum salt and nickel salt. The solution contains "at least about 0.2 moles of phosphoric acid per mole of molybdenum metal" and the molar ratio P / Mo is limited in some claims to 0.2: 1 - 0.8: 1.

U.S. Pat. Nos. 3,817,873 and 3,755,196 relate to a stable metal solution, a method of preparing this solution, a method of preparing a catalyst with this metal solution and the resulting catalyst. The metal solution contains molybdenum, nickel and / or cobalt and a phosphorus-containing acid, the molar ratio P / Mo being 0.1: 1 - 0.25: 1.

US Pat. No. 3,840,472 describes the preparation of an impregnation solution, wherein "the promoter solution of the invention consists essentially of molybdenum trioxide, at least one of said Group VIII metal compounds and phosphoric acid dissolved in water." The molar ratio P / Mo in the solution can range from 0.065: 1 to 2.5: 1.

In addition to the above single impregnation methods with op 80 0 1 9 93

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* - 3 - acid stabilized releases are known methods of preparing hydrogenation catalysts by multiple impregnations and / or stepwise methods of incorporating the active metals into the formed or non-formed support.

US Pat. No. 3,114,701 describes a catalytic hydrodenitrification process using a catalyst prepared by a number of impregnations of a formed support of aluminum oxide with aqueous solutions of nickel nitrate and ammonium molybdate so that the nickel content of the finished catalyst is 4-10 wt. .% and the molyb-10-dane metal content of the finished catalyst is 19-30% by weight, based on the calcined composition.

US Pat. No. 4,097,413 describes the preparation of a desulfurization catalyst by first mixing boehmite alumina with an aqueous solution of ammonium molybdate, drying the resulting mixture and then mixing it with a soluble cobalt salt. The mixture is then extruded and calcined.

US Pat. No. 4,049,115 describes a step-by-step method of preparing a desulfurization catalyst: Column 1, line 58 et seq. Of this US patent states that "... the invention relates to a desulfurization catalyst formed by an inorganic oxide as the support material, a Group VIB metal and a Group Vlli metal, which catalyst is prepared by (a) extruding at least 10% of the Group VIII metal with the inorganic oxide serving as the support material, and (b) impregnation of the obtained extrudate with a sufficient amount of the Group VIB and Group VIII metals to provide a finished catalyst containing the required metal content. "

The invention provides a new hydrogenation catalyst and a process for preparing this catalyst. The present new catalyst is an improved hydrogenation catalyst with high desulfurization and denitrogenation activity. The manufacturing process includes a two-step impregnation using a new acid-stabilized solution in at least one step.

In the field of catalytic hydrogenation, it is well known that materials containing cobalt as promoter give better desulfurization selectivity than materials containing nickel as promoter, while the reverse is true for denitrogenation. The invention also provides a nickel and molybdenum-containing catalyst with an unexpectedly high desulfurization activity, compared to the denitrogenation work 800 1 9 93

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ψ - 4 - ability.

In the field of catalyzed hydrogenation, it is also well known that by simply increasing the catalytically active metal content of a material, the activity at very high metal contents eventually begins to decrease. According to the invention, through the correct application of impregnation in a number of steps, the effectiveness of an increased metal content can be used efficiently.

Hydrogenation catalysts are prepared using multi-stage impregnation and a critical ratio between Group VIB metal and Group VIII metal in one or more steps, to yield catalysts having a removal activity. impurities from hydrocarbon materials, especially as regards the removal of both sulfur and nitrogen, which is higher than normal; these catalysts also contain a relatively small amount of an acidic residue, such as P2 ° 5, an acidic residue, and allow the use of a lower effective operating temperature for a predetermined percentage of contamination removal, for example, for 85% sulfur removal .

The invention provides an impregnation solution for the impregnation of a catalyst support in the preparation of catalysts for the hydrotreating of hydrocarbon materials, which solution is mainly formed by an aqueous solution of a Group VIB metal compound and a compound of a group VIB. Group VIII metal in amounts such that the molar ratio between Group VIB 25 metal and Group VIII metal is approximately 3: 1.

Furthermore, the invention provides a process for preparing a hydrogenation catalyst, according to which a support for a hydrogenation catalyst is impregnated with a hydrogenation metal in a number of steps, the impregnation being carried out with an impregnation solution in at least one of these steps .

"Furthermore, the invention provides a hydrogenation catalyst consisting essentially of a support which is impregnated in several steps with Group VIB and Group VIII metals, the impregnation being carried out in at least one step with a solution of Group 35 VIB metals and Group VIII in a molar ratio of about 3: 1, which solution may contain a stabilizing acid, the molar ratio of stabilizing acid to Group VIB metal being 0 - 0.087: 1.

A general method for preparing a hydrogenation catalyst used according to the invention comprises the following two-step Δ 800 1 9 93

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- 5 - impregnation method: a) Two impregnation solutions "A" and "B" are prepared; solution "A" contains a Group VIB metal and a Group VIII metal and a very small amount of stabilizing acid; solution "B" is a solution of a soluble Group VIII metal salt.

b) An alumina or alumina-silica support is impregnated with the metal solutions "A" and "B" or the equivalent.

c) The impregnated material obtained in step b) is formed by a known method and calcined.

d) The calcined material obtained in step c) is re-impregnated with solution "A" and calcined a second time.

An essential aspect of the invention is the preparation of solution "A". This solution contains about 3 moles of Group 15 VIB metal per mole of Group VIII metal and is stabilized with a small amount of acid. Generally, the stabilized solution "A" is prepared by mixing the required amounts of Group VIII and Group VIB metals in water with the acidic stabilizer. The mixture is then heated and kept at elevated temperature for a sufficient time to obtain a clear solution. This normally takes several hours at 82 ° C or higher temperature. The volume of the solution can be adjusted with water to obtain the desired concentration.

Some Group VIII metals suitable for use in the form of salts in the impregnation solution are iron, nickel and cobalt. Carbonate salts are preferred. Nickel carbonate is most preferred. Of the Group VIB metals suitable for obtaining a stable solution, preference is given to molybdenum and tungsten oxides. Most preferred is molybdenum trioxide. Examples of acidic stabilizers to be used are carboxylic acids, such as citric acid, gluconic acid, formic acid and acetic acid; and certain inorganic / oxygen containing acids. Most preferred is phosphoric acid.

The preferred solution "A" is prepared with nickel carbonate, molybdenum trioxide and phosphoric acid. Ni-Mo solutions with a concentration of 120 g of MoO2 / 1 or less were stable for 24 hours without addition of phosphoric acid. For concentrations above 120 g MoO / l, it was necessary to add a small amount of phosphoric acid to stabilize the solution for 24 hours. The concentration of the metals in this solution "A" can be varied from 17.5 g / l to 340 g / l MoO ^ with a @ 00 1993 - 6 - Έ maximum of 20.1 g / l ^. ^ 90 ^ (necessary for stabilization), i.e. a maximum molar ratio P / Mo of 0.087: 1. As mentioned above, solution "B" is the aqueous solution of a soluble salt of a Group VIII metal. The citrate salt is preferred. Nickel citrate is most preferred.

Any known alumina or silica-alumina support for hydrogenation catalysts can be used for the present catalyst.

Several methods are known for impregnating a catalyst support (see, for example, US Pat. No. 3,232,887). The preferred method for the first impregnation according to the invention is a hydrothermal method. However, other methods can also be used, such as impregnation of the pore volume or mixing or grinding operations. For the second impregnation step, several known methods of dispersing metals in a formed support can be used. The preferred methods of the invention are immersion or impregnation of the pore volume. The most preferred method is immersion. The formation of the catalyst can be carried out by any known method; extrusion and the formation of spheres are preferred. In the examples below, the present process and the activity of the resulting catalyst for hydrogenation processes are illustrated. The analytical data and the results of the catalyst effectiveness tests of all examples are shown in the table below.

EXAMPLE I

This example describes the preparation of the impregnation solutions.

Solution "A" (288 g / 1 MoO ^, 47.5 g / 1 NiO and 12.4 g / 1 P2 ° 5) was prepared as follows: A slurry of 9000 ml ^ 0 (21 ° C) was prepared C) with 2880 g of MoO4 and 144 ml of 75% HgPO4 · The nickel carbonate (820 g) was added over 15 minutes The mixture was heated to about 93 ° C with stirring and kept at this temperature for 2 hours. A clear green solution was obtained. The solution had a pH of 3.0, while the molar ratio P / Mo 35 was 0.087: 1. The volume of the solution was adjusted to 10 L with water. The solution was stable indefinitely ( for at least 6 months at room temperature).

Solution "B" (106 g / l NiO) was prepared as follows:

Anhydrous citric acid (80 g) was dissolved in 350 ml of about 24 ° C.

80 0 1 9 93 V * "- 7 -

73.3 g of nickel carbonate were then added over a period of 15 minutes.

The slurry was slowly heated to about 82 ° C with continuous stirring. After heating for 1 hour at about 82 ° C, all the NiCO 2 was dissolved and the pH was 3.8. The volume of the solution was adjusted to 400 ml with water.

Three variations of "A" solutions were prepared in order to determine the range of the amount of phosphoric acid required to obtain stable Ni-Mo solutions of different metal concentrations.

Solution "A" (Variation 1) - A Ni-Mo solution with 10 metal concentrations of 120 g / 1 MoO 3 and 19.8 g / 1 NiO was prepared according to the above method for solution "A". No phosphoric acid was added.

To prepare the solution, 5400 ml ^ 0 (about 27 ° C), 720 g MoO2 and 203 g NiCO2 were slurried. The mixture was stirred and heated to about 88 ° C. After heating for 2 hours at about 88 ° C, a clear green solution was obtained. The volume of the solution was brought to 6000 ml with water.

This solution was stable for about 24 hours, after which a green solid precipitated.

Solution "A" (Variation 2) - This solution was prepared in the same manner as Variation 1, except that 36 ml of 75% H 2 PO 2 20 were added to the 6000 ml final solution. This solution (120 g / l MoO2, 19.8 g / l NiO and 5.15 g / l was 9th stable for at least 45 days at room temperature. The molar ratio P / Mo of the solution was 0.087: 1.

Solution "A" (Variation 3) - This solution was prepared according to the above-described method for Solution "A", except that the amounts of the reactants were changed. The amounts were 900 ml ^ 0.340 g MqO ^, 96 g NiCO2 and 17 ml 75% H ^ PO2. The solution was brought to a volume of 1000 ml with water and was found to be stable for at least 45 days. The molar ratio P / Mo of the solution was 0.087: 1. The concentrations of the metals in the final solution were 340 g / l MoO 2 and 56 g / l NiO, while the P 2 O concentration was 14.6 g / l.

EXAMPLE II

This example describes the preparation of the catalyst of the invention. In this example, the solution "A" of Example I was used which contained 288 g / l MoO 2 and had a molar ratio P / Mo of 0.087: 1.

16.2 kg of alumina silica powder, containing 22% solids, were slurried in 4 L of water. The alumina-silica 800 1 9 93-8 contained 2.8% SiC 2 (based on the dry material) and the remainder mainly Al 2 O 3. The slurry was mixed with 2522 ml of solution "A" from Example I and 844 ml of solution "B" from Example I. The slurry was heated to about 93 ° C and kept at this temperature for 1 hour. After impregnation, the slurry was filtered. The filtrate was saved. The filter cake was dried at about 82 ° C for 2 hours. The impregnated and dried filter cake had a free moisture content of 42%, determined with a "0-Haus" moisture meter using a 10 g sample heated for 20 minutes, adjusted to 75. 10 about 8 was added. 2 kg of the dried filter cake in a Simpson mixer.

The filtrate (3800 ml) was also introduced into the mixer. The material was subjected to a mixing operation for 20 minutes and then extruded through a 0.185 cm nozzle at a free moisture content of 55%. The extrudates were pre-dried at about 149 ° C for 3 hours and then calcined at about 593®C for 2 hours. The calcined, impregnated extrudates after the first impregnation contained 17 wt.% MoO2, 3.73 wt.% NiO and 0.78 wt.% P2 ° 5. About 2.3 kg of the above-mentioned extrudate was immersed for 16 hours in 9080 ml of solution "A". After impregnation, the solution was allowed to drain and the impregnated catalyst was dried beforehand at about 149 ° C, after which it was calcined at about 593®C for 2 hours.

The finished catalyst contained 28 wt.% MoO 2, 6.4 wt.% NiO and 3.1 wt.% P 2 O 2. The chemical analysis is given in the table below.

EXAMPLE III

This example is for comparison with Example II; in this example, the immersion time was shortened from 16 hours to 1 hour. All other catalyst preparation steps were the same as in Example II. The analysis results are given in the table below.

EXAMPLE IV

This example shows the effect of low metal contents after the first impregnation. The catalyst was prepared in the same manner as the catalysts in Examples II and III, except that in this example the calcined extrudate after the first impregnation was 11.8 wt.% MoO, 3.51 wt. 50% by weight. After an immersion time of 1 hour in the second impregnation, the finished catalyst contained 26.2 wt.% MoO2, 5.59 wt.% NiO and, 1.6 wt.% P2®5. The analysis results are in the given in the table below.

EXAMPLE V

In this example, the metal contents after the first impregnation 800 1 9 93 - 9 - are further reduced; after the first impregnation, the extrudate contained 5.9 wt.% MoO2, 3.08 wt.% NiO and 0.05 wt.% P2 ° 5. The impregnation of metals in the first step was carried out by the adding metals such as MoO 2 and NiCO 2 and citric acid in solid form instead of as solutions "A" 5 and "B". In all other respects, the preparation of the finished catalyst followed the procedure described in Examples III and IV. The final catalyst obtained contained 23.6 wt% MoO 2, 5.76 wt% NiO and 1.3 wt% P2® 5 * analytical results are shown in the table below.

EXAMPLE VI

This example shows the effect of completely omitting the Group VIB metal from the first impregnation step. The procedure of Example V was followed, with the difference, however, that only nickel carbonate and citric acid were used in the impregnation of the aluminum oxide-silica support. The extrudates obtained after the first impregnation step contained 2.85 wt% NiO and the catalyst obtained after the second impregnation step contained 22.8 wt% MoO, 5.85 wt% NiO and 1.4 wt% P2 ° Analytical results are given in the table below.

EXAMPLE VII

This example shows the effect of the concentration of the solution during the last impregnation on the activity of the catalyst.

The calcined extrudate obtained after the first impregnation step was prepared according to the procedure described in Example IV. In the second impregnation, 454 g of the calcined extrudate was immersed in 1816 ml of impregnation solution "A" with a MoO 2 concentration of 200 g / l (instead of a MoO 2 concentration of 288 g / l as in Example IV). . The analytical results are given in the table below.

EXAMPLE VIII

This catalyst was prepared by the same method as in Examples IV and VII, except that the MoO 2 concentration in solution "A" in the last impregnation step was 120 g / l. The analytical results are given in the table below.

EXAMPLE IX

This example shows the use of impregnation of the pore volume in the second impregnation step. The calcined extrudates obtained after the first impregnation were prepared by a similar method as in Example II to obtain a material containing 14.6 wt.% MoO4, 4.55 wt.% NiO and 0.93 wt.% . The support (7302 g) was impregnated with 4554 ml of solution "A" (288 g / 1 MoO ^) @ 00 1 9 93 ψ -10- ^ by passing the liquid into an evacuated tumbling bed of the extrudate. feed. The impregnated extrudate was dried and calcined at about 593 ° C for 2 hours. The analytical results are shown in the table below.

EXAMPLE X

This example demonstrates the use of the present catalysts for hydrogenation treatments. Each of the catalysts of Examples II-IX was tested for its hydrogenating activity. The activities were determined in comparison to a commercially available hydrogenation catalyst containing 10 Ni and Mo. The analysis of the reference catalyst is shown in the table (Example X). 60 ml of each of the catalysts to be tested and of the reference catalyst were tested for the desulfurization and denitrogenation activity on a vacuum gas oil (specific gravity 0.934, boiling range approximately 394 - 574®C), which was 2.8 wt% sulfur and 1560 ppm nitrogen. The test conditions were as follows: approximately 357®C, 6895 kPa (gauge pressure), liquid velocity per 3 hours (oil volume / hour / catalyst volume) 1.5 and 0.730 standard m hydrogen / liter. The catalysts were placed in adjacent tubular reactors in an isothermal sand bath.

The reference catalyst was assigned a standard activity value of 1.00 on a volume basis. The activities of the investigated catalysts are reported relative to this standard (on a volume basis). The values for the activity are given in the table below.

EXAMPLE XI

This example demonstrates the superior maintenance of the activity of the present catalyst compared to a commercially available,

Co and Mo-containing catalyst for desulfurizing a mixture of vacuum gas oil and vacuum residue. This starting material is more difficult to treat than vacuum gas oil or lighter distillates alone. The catalyst of the invention tested in this example was prepared by a similar process as in Example II. The catalysts (extrudate about 0.16 cm) were charged in equal volumes in identical electrically heated tubular reactors from a pilot plant; the catalysts were previously subjected to a conventional sulfidation activation treatment and then put into service to desulfurize a mixture described below. The reactor temperatures were raised as needed to maintain 85% desulfurization and the test was continued under the conditions listed below for 24 days. The superior maintenance of the catalyst activity of the invention according to the invention is evident both from a lower operating temperature and from a lower temperature increase over the long operating period. Properties of starting material (mixture)

Specific gravity 0.900 5 Flash point, ®C 152

Carbon acc. Ramsbottom, wt% 1.91

Sulfur, wt% 0.62

Nitrogen, wt% 0.114

Distillation, ASTM D-1160 10 Initial boiling point, ®C 214.5 10% 300 50% 399.5 90% 568

Test conditions 15 Start temperature of the test, ®C 365.5

Reactor pressure, kPa (gauge pressure) 8446

Fluid velocity oil per hour 1.74

Ratio hydrogen / oil-ie, standard m3 / liter _ 0.356 20 Catalyst properties acc. the invention

Mo03 27%

NiO 6.7% P205 2.25%

Average bulk density 0.92 g / ml 25 Efficacy results

Operating time Required temperature for 85% desulfurization, ®C

(number of days) Catalyst acc. the invention Reference catalyst 5 370.0 372.2 10 374.0 378.3 30 15 376.7 382.8 20 377.8 385.9 24 378.3 387.8 800 1 9 93 - 12 -

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ASSESSMENT OF RESULTS

The above examples demonstrate several unique properties of the present catalyst.

From the data of the table above, it is apparent that over a wide range of preparation conditions, the present catalyst exhibited an activity superior to that of the commercially available nickel and molybdenum containing catalyst in both denitrogenation and desulfurization. Furthermore, in all cases the improvement in desulfurization efficacy was still 4-26% greater than the improvement in denitrogenation efficacy. Example XI shows superior desulfurization activity even over a commercially available cobalt and molybdenum containing catalyst.

The amount of Group VIB metal added to the catalyst in the first step ranges from 0 to 17%, with the greatest improvement in activity at the high levels being obtained (Examples II, III, IV, V, VI). The second impregnation step is carried out by immersion or impregnation of the pore volume. In the examples employing the immersion method, the time ranged from 1 to 16 hours (Examples II and III) and the MoO 2 concentration of the immersion solutions ranged from 120 g / l to 288 g / l ( Examples IV, VII and VIII).

As can be seen from the examples, the catalysts generally generally contain 21-30% MoO5, 5-7% NiO and 1.0-3.5% P2 ° 5. The 25 mol ratio between Group VIB metal and metal from group VIII of approximately 3: 1 appears to be critical. The multi-step impregnation of the catalyst support using impregnation solutions of the type described herein is also an important aspect of the invention. Furthermore, a considerable improvement has been obtained by using the immersion impregnation method, compared to other methods such as impregnation of the pore volume.

The ability of a catalyst to desulfurize a hydrocarbon material with a predetermined high degree of low temperature desulfurization, as shown in Example XI, is a very important factor in processes of this type because the use of low temperatures results in lower costs .

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Claims (19)

Impregnation solution for impregnating a catalyst support in the preparation of catalysts for hydrotreating hydrocarbon materials, characterized in that the impregnation solution 5 is essentially an aqueous solution of a Group VIB metal compound and a compound of a Group VIII metal in amounts such that the molar ratio between Group VIB metal and Group VIII metal is approximately 3: 1. Solution according to claim 1, characterized in that the Group VIB metal is molybdenum and the Group VIII metal is nickel or cobalt. Solution according to claim 1 or 2, characterized in that the solution is stabilized by a stabilizing acid. Solution according to claim 3, characterized by phosphoric acid as a stabilizing agent in a small amount not greater than that corresponding to a molar ratio of phosphorus to metal of group VIB of 0.087: 1. Process for the preparation of a hydrogenation catalyst, characterized in that a support for a hydrogenation catalyst is impregnated with a hydrogenation metal in a number of steps, the impregnation being carried out in at least 20 of these steps with an impregnation solution according to one or more of the preceding claims. 6. Process according to claim 5, characterized in that at least one impregnation step with the impregnation solution is carried out hydrothermally. 7. Process according to claim 5, characterized in that two impregnations with the impregnation solution are used, wherein the second impregnation is carried out by immersion in the impregnation solution. Process according to claim 5, 6 or 7, characterized in that the impregnation solution is prepared by dissolving nickel carbonate and molybdenum trioxide in water, the molybdenum trioxide concentration being 17.5 - 30 340 g per liter, which solution is also a stabilizing amount contains phosphoric acid when the amount of molybdenum trioxide exceeds 120 g per liter of solution, the stabilizing amount of phosphoric acid being no greater than the amount of phosphoric acid corresponding to a maximum molar ratio P / Mo of 0.087: 1. 9. Process according to claim 5, 6 or 7, characterized in that an impregnation solution is used containing 288 g / m Mou 4, 47.5 g / 1 NiO and 12.4 g / 1 P 2 Or. 2 b 10. Process according to claim 5, characterized in that the catalyst support is slurried in water and mixed with the impregnation solution, which contains soluble forms of molybdenum oxide and nickel oxide, and the second impregnation solution. -pregnating solution containing a soluble form of nickel oxide without molybdenum oxide, filtering the slurry and drying, mixing the dried impregnated filter cake with the filtrate and extruding, pre-drying and calcining the extrudate, immersing the calcined, impregnated extrudate in the irapregating solution of soluble forms contains both molybdenum oxide and nickel oxide, and the resulting impregnated catalyst dries and calcines beforehand. A hydrogenation catalyst, characterized by a catalyst support 10 which is impregnated in several steps with Group VIB and Group VIII metals, the impregnation being carried out in at least one step with a solution of a Group VIB metal and a Group VIII metal in a molar ratio of about 3: 1, which solution may contain a stabilizing acid, the molar ratio of stabilizing acid to Group VIB metal 15 being 0 to 0.087: 1. Catalyst according to claim 11, characterized in that the stabilizing acid residue is 5 * Catalyst according to claim 11 or 12, characterized in that the group VIB metal is molybdenum and the metal nit group VIII is nickel or cobalt. Catalyst according to claims 11-13, characterized by 21-30 wt.% MoO5, 5-7 wt. % NiO and 1.0-3.5 wt. % * Catalyst according to claim 14, characterized by about 26.1 wt% MoO ^, 5.41 wt% NiO and 3.1 wt% ^ 2 ^ 5 * Catalyst according to claim 14, characterized by about 26.1 wt.% MoO4, 5.59 wt.% NiO and 1.6 wt.% P2 ° 5 * Catalyst according to claim 14, characterized by about 25.4 wt.% ΜοΟ,, 5.29 wt.% NiO and 1.7 wt. Catalyst according to claim 14, characterized by about 23.2% by weight 30 MoO2, 5.24 wt% NiO and 1.5 wt% P2 ° 5 ' Process for the hydrotreating of hydrocarbon materials while removing sulfur, nitrogen and / or metals, characterized in that the hydrocarbon material is subjected to catalytic conversion in the presence of a catalyst according to claims 11-18, 800 1 9 93