JPH0512023B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a catalyst for hydrotreating heavy oil, and more specifically, it is used in the hydrotreating of heavy oil to facilitate the diffusion of high molecular weight molecules into the pores of the catalyst. A heavy oil that exhibits high reactivity with molecules, generates little naphtha gas that increases hydrogen consumption, and has excellent performance that does not lose activity even when carbonaceous substances and heavy metals accumulate. Concerning hydrotreating catalysts. In recent years, with the increase in the consumption of heavier crude oil as well as kerosene oil called desulfurized oil, demetalized oil, denitrified oil, and middle distillate, oil containing organic metal compounds including asphaltenes, resins, and nickel/vanadium has increased. A method has been put into practical use in which heavy oil is treated under pressure with hydrogen in the presence of a catalyst to obtain desulfurized oil, demetalized oil, denitrified oil, kerosene, and the like. The conventional zeolite-containing catalysts used in these hydrotreating reactions, i.e., hydrodesulfurization, hydrodemetallation, hydrodenitrogenation, and hydrocracking reactions, have the majority of their pores less than 200 Å in diameter. The dimensions are as follows.
However, when a catalyst with such pores is used, carbonaceous substances, nickel, and vanadium generated by the decomposition of heavy oil at the pore entrances accumulate around the pore entrances. Although it does not completely block the pore, it narrows the pore entrance diameter.
Entry of high molecular weight molecules into the pores is inhibited, and only low molecular weight molecules enter the pores and are overly decomposed into smaller molecules by the zeolite present within the pores. This not only leads to an increase in gas production and hydrogen consumption, but also causes the rapid accumulation of carbonaceous substances on the zeolite and within the zeolite pores, which is the main reason for the sudden decrease in activity. . In other words, conventional zeolite-containing hydrotreating catalysts have problems such as decreasing activity in a short period of time, producing large amounts of low-value gas, and consuming a large amount of hydrogen. There are many problems as a catalyst for obtaining distillates. Additionally, the deposition of carbonaceous substances, nickel, and vanadium within the catalyst particles causes stress at the grain boundaries due to carburization, or the stress is reduced by the growth of precipitated nickel and vanadium within the pores. This can cause destruction of catalyst particles. In addition, carbonaceous substances, nickel, and vanadium deposited on the outer surface of the catalyst cause the catalyst particles to coagulate with each other as they grow, causing catalyst aggregates to occur. When this phenomenon occurs, the pressure difference between the top and bottom of the catalyst layer We must be concerned about inconveniences such as an increase in water and clogging of reaction tubes. An object of the present invention is to provide a catalyst that eliminates the above-mentioned drawbacks and can maintain excellent reactivity over a long period of time. That is, the present invention provides a catalyst in which the accumulation of carbonaceous material, nickel-vanadium, near the entrance of catalyst pores is small, the phenomenon of catalyst pore clogging can be prevented for a long period of time, and the hydrotreating activity can be maintained for a long period of time. It is something to do. The catalyst of the present invention has particularly technical significance in pores with a diameter of 200 Å or more, and has a large number of pores with a diameter of 200 Å or more. Three-dimensionally applied within the catalyst
Large pores of 200 Å or more are deposits of carbonaceous materials,
It is not easily blocked by the accumulation of nickel/vanadium, and the carbonaceous material and nickel/vanadium deposited around the pore entrance prevents the high molecular weight molecules to be treated from entering the pore. It is thought that this also prevents excessive decomposition of low molecular weight molecules. On the other hand, after undergoing preliminary hydrogenation treatment in pores with a pore diameter of 200 Å or more,
The lightened heavy oil undergoes further hydrogenation treatment by being diffused onto zeolite, but this lightened heavy oil undergoes preliminary treatment.
It is thought that the deposition effect of carbonaceous substances on the zeolite and within the zeolite pores is alleviated, and the activity can be maintained over a long period of time. The validity of these estimates is that when a few percent of asphaltenes are removed from the feedstock heavy oil before hydrotreating, and then hydrotreating is carried out using a conventional zeolite-containing catalyst, excellent activity and long catalyst life are obtained. This would also be supported by the fact that the amount of hydrogen consumed is reduced. The heavy oil hydrotreating catalyst according to the present invention is a catalyst in which a hydrogenation active metal is supported on a catalyst carrier made of Y-type zeolite and alumina, and the pore characteristics of the catalyst are as measured by mercury porosimetry. , (a) the volume of pores with diameters ranging from 200 Å to 5000 Å is 45% to 100% of the volume of pores having diameters ranging from 60 Å to 5000 Å, and (b) diameters ranging from 60 Å to 150 Å (c) the volume of pores with a diameter in the range of 60 Å to 5000 Å is 45 to 0% of the volume of pores with a diameter in the range of 60 Å to 5000 Å; g, preferably 0.14~
(d) When the pore diameter of the maximum peak of the pore distribution curve within the pore diameter range of 600 to 5000 Å is d,
The volume of pores with diameters ranging from 10 ^logd-0.3 Å to ^{10 logd+0.2} Å is 40-100% of the volume of pores with diameters ranging from 60 to 5000 Å. It is characterized by In addition, pore distribution measurement by mercury intrusion method is
Using CALRO ERBA's mercury intrusion type pore distribution measuring device model 220, the contact angle was 130° and the surface tension was measured.
The pore diameter α at ^the maximum peak was determined from the differential curve. In the catalyst of the present invention, the more pores having a diameter of 200 Å to 5000 Å and the fewer pores having a diameter of 60 Å to 150 Å, the longer the catalyst life will be. In addition, the catalyst life will be longer if the pore volume with a diameter of 600 Å to 5000 Å is large, but if the pore volume in this range exceeds 0.40 ml/g, it will not be possible to maintain sufficient catalytic strength, so it cannot be used as an industrial catalyst. is not desirable. In the catalyst of the present invention, the zeolite used as the carrier component is preferably Y-type haujasite, which has a large pore size and high heat resistance among various zeolites. In addition, in order to reduce unnecessary gas generation and naphtha generation, and to obtain high activity above a certain level, the zeolite is 24.30 to 24.45 Å
It is preferable to have a unit cell constant of , a SiO ₂ /Al ₂ O ₃ molar ratio of 6 to 30, and a Na ₂ O content of 4 wt% or less. By the way, the unit cell constant is 24.30 ~
Zeolite that has been treated to become 24.45Å is
Many pores, several tens of Angstroms wide, are generated in the zeolite.
It also has a large external surface area, making it ideal for processing heavy oil with a large molecular weight. When the unit cell constant is 24.45Å or more, most of the zeolite pores are
Since it is less than 10Å, a lot of gas and naphtha are generated.
Furthermore, zeolite that has been treated to have a unit lattice constant of 24.30 Å or less cannot obtain the desired activity because the zeolite crystal structure has been destroyed. The catalyst of the present invention can be manufactured by first preparing a carrier and supporting the hydrogenation active metal on the carrier. According to this method, a catalyst carrier is obtained by mixing the above zeolite with alumina and molding the mixture so that the zeolite content of the carrier is 20 to 80 wt%. In order to obtain a carrier with preferable performance, a part or all of the alumina used as a carrier component is obtained by the following method. That is, after adding the zeolite to an acidic aqueous solution of aluminum sulfate, nitrate, acetate, etc.
Add ammonia water or a basic solution such as sodium hydroxide to precipitate the aluminum in the solution in the form of hydroxide, or add ammonia water or hydroxide to an acidic aqueous solution of aluminum sulfate, nitrate, or acetate. Immediately add the above zeolite to aluminum hydroxide obtained by adding a basic aqueous solution such as sodium, filter the resulting mixture,
A carrier is obtained by washing, quenching, molding, drying, and firing. Finally, a hydrogenation active metal such as nickel or tungsten is supported by a known method to obtain the catalyst of the present invention. As the hydrogenation active metal, one or more metals selected from the groups and groups of the periodic table are used, and these metals are supported on the catalyst carrier by a conventional method. The amount supported is group metal and the weight of the catalyst is
0.5% to 5%, 5% to 24% for group metals, and 1% to 8% for group metals (all calculated as elemental metals); however, group metals and metals from other groups When used in combination with metals, the lower limit of the supported amount is approximately 1% for group metals and approximately 0.5% for group metals.
It can be reduced to %. The zeolite-containing catalyst thus obtained exhibits significantly improved activity and catalyst life for reactions such as hydrodesulfurization, demetalization, denitrification, and cracking of heavy oils. The heavy oil hydrotreating catalyst of the present invention is particularly suitable for hydrodesulfurization, hydrodemetalization, hydrodenitrogenation, and hydrocracking reactions of heavy oils, of which atmospheric residual oil and vacuum residual oil are typical examples. However, it can also be used for hydrogenation of vacuum gas oil, visbreaking oil, tar sand oil, etc. By using the catalyst of the present invention, heavy oil can be hydrotreated under a wide range of reaction conditions ranging from relatively mild reaction conditions to severe reaction conditions. The reaction conditions are: reaction temperature 300-500℃, reaction pressure 40-300Kg/cm ² , hydrogen to oil ratio 200-
3000nM ³ /Kl, LHSV0.1~10.0hr ^-1 , hydrogen concentration
70vol% or more is usually adopted. The present invention will now be described in more detail with reference to Examples. Example 1 Unit cell constant 24.37 Å, SiO ₂ /Al ₂ O ₃ molar ratio
14.0, after suspending 1000 g of Y-type zeolite with a Na content of 0.7 wt% as Na ₂ O in 3.4 Kg of water, a 2 wt% aluminum sulfate aqueous solution 50.3
Kg was added and thoroughly stirred, and then 5% aqueous ammonia was added to adjust the pH to 7.0. Stir as it is for 20 minutes, then heat to 60°C, stir for 1 hour, filter and dehydrate the resulting cake-like material at 0.05%
Washing was performed with 150 kg of ammonia aqueous solution. This was dried at 110°C for 16 hours, then calcined at 550°C for 1 hour, and then suspended in 3.0 kg of water. [Hereafter referred to as suspension (A)] Next, 50 wt% gluconic acid aqueous solution was added to 80 kg of sodium aluminate solution with a concentration of 5.0 wt% as Al ₂ O ₃ .
After adding 240 g, 85 kg of an aqueous aluminum sulfate solution having a concentration of 2.5 wt% as Al ₂ O ₃ was added to obtain 165 kg of alumina slurry with a pH of 7.0. This solution was filtered and dehydrated and then washed with a 0.2 wt % ammonia aqueous solution 450 to obtain a pseudoboehmite-containing alumina hydrate having a concentration of 8.5 wt % as Al ₂ O ₃ . Add a small amount of ammonia aqueous solution to this alumina hydrate to reduce the Al ₂ O ₃ concentration.
A slurry of 8.4wt% and pH 10.60 was obtained. This was kept at 95°C for 20 hours with stirring. Thereafter, the mixture was heated and concentrated using a kneader to obtain an alumina hydrate Y having a concentration of 34 wt% as Al ₂ O ₃ . Add the above alumina hydrate Y1.08 to the suspension A obtained earlier.
Kg was mixed and heated in a kneader, and then molded into pellets with a diameter of 1 mm using a conventional method. This is 110
The mixture was dried at ℃ for 16 hours and calcined at 550 ℃ for 3 hours to obtain a carrier. Add ammonium paratungstate to 660g of this carrier.
After adding 396 ml of an aqueous solution containing 161 g of nickel nitrate and 132 g of nickel nitrate for impregnation, the catalyst was dried at 250°C for 2 hours and further calcined at 550°C for 1 hour to obtain a catalyst. The supported amounts of tungsten and nickel in this catalyst A are 13.5 wt% and 3.1 wt%, respectively, as oxides.
It was hot. Table 1 shows the pore characteristics of the carrier and catalyst thus obtained as measured by mercury porosimetry. Example 2 1000g of Y-type zeolite used in Example 1
After suspending in 3.4Kg of water, 67.1Kg of 2wt% aluminum sulfate aqueous solution was added, stirred thoroughly, and then
% of ammonia water was added to adjust the pH to 7.0. The mixture was stirred as it was for 20 minutes, then heated to 60°C and stirred for 1 hour, followed by filtration and dehydration, and the resulting cake-like material was washed with 150 kg of 0.05% ammonia aqueous solution.
Thereafter, this cake was dried at 110°C for 16 hours, then baked at 550°C for 1 hour, and then suspended in 3 kg of water. 782 g of alumina hydrate Y obtained in the same manner as in Example 1 was mixed with this suspension and heated in a kneader.
After the mixture was mixed, it was molded into pellets with a diameter of 1 mm using a conventional method. This was dried at 110℃ for 16 hours, and then dried at 550℃ for 3 hours.
A carrier was obtained by firing for a period of time. Tungsten and nickel were supported on this carrier by the method of Example 1 to obtain catalyst B. The amounts of tungsten and nickel supported were almost the same as in Example 1. The pore characteristics of the carrier and catalyst thus obtained are shown in Table 1, and the pore distribution curve of Catalyst B is shown in FIG. Example 3 1000g of Y-type zeolite used in Example 1
After suspending in 3.4 kg of water, 111.5 kg of a 2 wt% aluminum sulfate aqueous solution was added and thoroughly stirred, and then 5% aqueous ammonia was added to adjust the pH to 7.0. The mixture was stirred as it was for 20 minutes, then heated to 60°C and stirred for 1 hour, followed by filtration and dehydration, and the resulting cake-like material was washed with 150 kg of 0.05% ammonia aqueous solution.
Thereafter, this cake was dried at 110°C for 16 hours and then baked at 550°C for 1 hour. After crushing, the mixture was placed in a kneader, water was added thereto, the mixture was mixed, and the mixture was molded into pellets with a diameter of 1 mm using a conventional method. this
It was dried at 110°C for 16 hours and fired at 550°C for 3 hours to obtain a carrier. Catalyst C was prepared by supporting tungsten and nickel on this carrier using the method of Example 1. The amounts of tungsten and nickel supported were almost the same as in Example 1. The pore characteristics of the carrier and catalyst thus obtained were as shown in Table 1. Comparative Example 1 500g of Y-type zeolite used in Example 1 was
After suspending the suspension in 1 kg of water, 980 g of the alumina hydrate Y obtained in Example 1 was mixed, heated and homogenized in a kneader, and then molded into pellets with a diameter of 1 mm using a conventional method. This was dried at 110°C for 16 hours and calcined at 550°C for 3 hours to obtain a carrier. Next, according to Example 1, catalyst D was prepared by supporting tungsten and nickel. The amount of metal supported was the same as in Example 1. The pore characteristics of this catalyst and its carrier are shown in Table 1, and the pore distribution curve of Catalyst D is shown in FIG. Comparative Example 2 1960 g of alumina hydrate Y used in Example 1 was heated and dried in a kneader, then calcined at 550°C for 3 hours, cooled, and then ground. Add 1000g of Y-type zeolite used in Example 1 to this powder, then add 3.4kg of water.
was added and heated in a kneader, and then molded into pellets with a diameter of 1 mm using the usual method. This at 110℃
It was dried for 16 hours and fired at 550°C for 3 hours to obtain a carrier. Next, according to Example 1, catalyst E was prepared by supporting tungsten and nickel. The amount of metal supported was the same as in Example 1. The pore characteristics of the carrier and catalyst thus obtained were as shown in Table 1.

[Table] Example of using catalyst In order to confirm the effects of the present invention, a hydrogenation reaction of atmospheric residual oil was carried out using catalysts A to E under the following conditions. The reactor has an inner diameter filled with catalyst 300c.c.
A 19 mm, 3 m long fixed bed reactor was used. Raw material oil properties Specific gravity 0.971 (15/4℃) 343℃ ⁺ 94vol% Viscosity 240cst (at 50℃) Sulfur 4.02 Nitrogen 2200ppm Vanadium 50ppm Nickel 15ppm Reaction conditions Reaction pressure 150Kg/cm ² Hydrogen/oil ratio 2000nM ³ / Kl LHSV 0.3hr ^-1 Hydrogen concentration 90vol% The results are shown in Figure 3 a to f, and the catalyst of the present invention was excellent in terms of kerosene yield, 343℃ ^-1 conversion rate, and desulfurization rate. It shows the value and shows that it has a long lifespan.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 are graphs showing the pore distribution of catalyst B of the present invention and comparative catalyst D, respectively, and FIG. 2 is a graph showing the reaction results when used in the hydrogenation treatment of

Claims (1)

[Claims] 1. A catalyst in which a hydrogenation active metal is supported on a catalyst carrier made of Y-type zeolite and alumina, which has the following pore characteristics as measured by mercury intrusion method.
(a) A catalyst for hydrotreating heavy oil, characterized in that it satisfies the conditions of (a) to (d). (b) the volume of the pores having a diameter in the range of 60 Å to 150 Å is 45% to 100% of the volume of the pores having a diameter in the range of 60 Å to 5000 Å; (c) the volume of pores with a diameter in the range of 600 Å to 5000 Å is 0.10 to 0.40 ml/g; and (d) the maximum peak of the pore distribution curve within the range of pore diameters of 600 Å to 5000 Å. When ^d is the pore ^diameter of be. 2 The unit cell constant of zeolite is 24.30 to 24.40 Å
and the SiO ₂ /Al ₂ O ₃ molar ratio is 6.0 to 30.0,
The catalyst according to claim 1, characterized in that the alkali metal content is 4 wt% or less as Na ₂ O. 3. The catalyst according to claim 1, wherein the hydrogenation-active metal is one or more metals selected from Groups and Groups of the Periodic Table.