JP3676869B2 - Method for producing hydrodesulfurization catalyst for hydrocarbon oil - Google Patents

Description

【００５３】
実施例および比較例に使用した触媒の組成および物性と、反応結果（比較例１を１００としたときの相対活性値）を表２に示す。
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【表２の１】

【００５５】
【表２の２】

【００５６】
【表２の３】

【００５７】
【表２の４】

【００５８】
【表２の５】

【００５９】
【発明の効果】
本発明の製造方法で得られる水素化脱硫触媒によれば、燐およびＩＩＡ族金属成分の両方が含有されているため、脱硫活性が非常に優れており、しかも硫黄分０．０５質量％において問題となる難脱硫性物質である４Ｍ−ＤＢＴ、あるいは４．６ＤＭ−ＤＢＴの脱硫にも十分対応することができるので、非常に効果的である。
しかも、従来の触媒製造法と比して、コスト的にも何ら遜色ない。
このように、本発明の方法により得られる触媒は、硫黄含有量の少ない燃料油を効果的に製造することができるため、実用上極めて有効である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for producing a catalyst suitable for hydrodesulfurization of hydrocarbon oils, particularly light oils, particularly for deep desulfurization.
[0002]
[Background Art and Problems to be Solved by the Invention]
Hydrocarbon oils generally contain sulfur compounds, and when these oils are used as fuel, sulfur present in the sulfur compounds is converted into sulfur oxides and released into the atmosphere.
Therefore, considering the air pollution when combusted, it is desirable that the sulfur content in the hydrocarbon oil is as low as possible.
A hydrocarbon oil having a low sulfur content can be obtained by catalytic hydrodesulfurization treatment of hydrocarbon oil.
[0003]
A catalyst conventionally used in this hydrodesulfurization treatment is one in which cobalt or molybdenum is used as an active metal and is supported on an oxide carrier such as alumina, magnesia, or silica.
In order to improve the activity of this catalyst, techniques for adding phosphorus have also been reported (see Japanese Patent Laid-Open Nos. 52-13503, 2-214544, and 6-121931).
As a method for supporting these active metals, an impregnation method using an aqueous solution of a salt of each metal is widely used. For example, an ammonium salt is mainly used for a molybdenum component.
[0004]
In addition, as regulations on sulfur content in commercial diesel oil become more stringent due to environmental problems (0.5 mass% → 0.2 mass% → 0.05 mass%), further deep desulfurization is being demanded, Further desulfurization treatment is required.
And in the area | region whose sulfur content in commercial light oil is 0.05 mass% or less, the sulfur compound which exists is limited to several types, and they are expressed as a hardly desulfurization substance.
Those recognized as these representative compounds are 4 methyl-dibenzothiophene (hereinafter, 4M-DBT) or 4,6 dimethyl-dibenzothiophene (hereinafter, 4,6DM-DBT).
[0005]
Therefore, in order to achieve deep desulfurization of 0.05% by mass or less, the desulfurization catalyst is inevitably required to have the ability to cope with these difficult desulfurization substances.
Considering such a background, it is considered that the current impregnation method does not make full use of the effect in the above-described technique for impregnating and adding phosphorus.
[0006]
Accordingly, an object of the present invention is to provide a method for producing a catalyst which can sufficiently exhibit the effect of adding phosphorus and can also remove the above-mentioned hardly desulfurizing substance satisfactorily.
[0007]
[Means for Solving the Problems]
As a result of repeated studies to achieve the above object, the present inventors have made an active component composed of a cobalt component and a molybdenum component contain a phosphorus and a Group IIA metal in the periodic table in a support composed of an inorganic oxide, and When a catalyst was prepared by a specific method, the catalyst was found to exhibit excellent performance in a hydrodesulfurization reaction in which sulfur contained in light oil was desulfurized to 0.05% by mass or less, and the present invention was completed. It came to.
[0008]
That is, according to the present invention, a carrier composed of an inorganic oxide has a molybdenum component of 10 to 30% by mass in terms of oxide, a cobalt component of 3 to 7% by mass in terms of oxide, and a phosphorus component of 0.1 to in terms of oxide. -4 mass%, and a periodic table IIA (hereinafter referred to as IIA) group metal component in an amount of 0.1-2 mass% in terms of oxide, and this loading is carried out in the first stage with a phosphorus component and a periodic table group IIA The gist of the present invention is a method for producing a hydrodesulfurization catalyst, wherein the metal component is impregnated by impregnating a molybdenum component in the second stage and a cobalt component in the third stage.
[0009]
The carrier used in the present invention is an inorganic oxide.
Various inorganic oxides can be used, such as silica, alumina, boria, magnesia, titania, zirconia, silica-alumina, alumina-magnesia, alumina-boria, alumina-zirconia, etc. Alumina-silica and alumina-zirconia are preferable, and γ-alumina among alumina is particularly preferable.
These inorganic oxides can be used alone or in combination of two or more.
[0010]
The carrier of the present invention may contain clay minerals such as montmorillonite, kaolin, halosite, bentonite, adaval guide, kaolinite, nacrite, anorcite alone or in combination of two or more.
[0011]
The specific surface area, pore volume, and average pore diameter of the carrier comprising the above components are not particularly limited, but in order to obtain a catalyst for the purpose of deep desulfurization of gas oil fractions, The surface area is preferably 250 m ² / g or more, the pore volume is preferably 0.3 to 1.2 cc / g, and the average pore diameter is preferably 50 to 130 kg.
[0012]
Among the components supported on the carrier, various starting materials for the molybdenum component can be used, but inorganic compounds are preferred.
For example, ammonium molybdate represented by (NH ₄ ) ₆ Mo ₇ O ₂₄ , molybdenum oxide represented by MoO ₃ , and the like can be given.
These inorganic compounds can be used alone or in combination of two or more.
[0013]
Various starting materials for the cobalt component can be used, but inorganic compounds are preferable, and nitrates, carbonates, and acetates are particularly preferable.
These cobalt component inorganic compounds can be used alone or in combination of two or more.
[0014]
Examples of the phosphorus component include orthophosphoric acid, metaphosphoric acid, triphosphoric acid, tetraphosphoric acid, and polyphosphoric acid, and orthophosphoric acid is particularly preferable.
These phosphorus components can be used alone or in combination of two or more.
[0015]
As the IIA group metal component, calcium, magnesium, barium and strontium are preferable, and calcium and strontium nitrates are particularly preferable.
These Group IIA metal component components can be used alone or in combination of two or more.
[0016]
The solvent for dissolving each of the supported components is not particularly limited, and various solvents can be used. For example, water, alcohols, ethers, ketones can be used in any supported component. , Aromatics and the like, preferably water, acetone, methanol, n-propanol and the like, particularly preferably water.
These solvents can be used alone or as a mixed solvent in which two or more kinds are mixed.
[0017]
The ratio of each component dissolved in the above solvent is 10 to 30% by mass, preferably 18 to 25% by mass, and 3 to 7% by mass of the cobalt component in terms of oxides with respect to the catalyst after calcination. The amount is preferably 4 to 6% by mass.
When the ratio of the molybdenum component is less than 10% by mass, the catalytic activity is not sufficient, and when it exceeds 30% by mass, the specific surface area of the catalyst is reduced and the catalytic activity is reduced (that is, molybdenum adheres to each other). , Active points tend to decrease).
When the proportion of the cobalt component is less than 3% by mass, the catalyst activity is not sufficient, and when it exceeds 7% by mass, the entire catalyst is covered and the catalyst activity is likely to be reduced (that is, the cobalt covers the molybdenum). As a result, the active site of molybdenum decreases.
[0018]
The ratio of the phosphorus component is an amount that is 0.1 to 4% by mass, preferably 1 to 2% by mass, in terms of oxide, with respect to the catalyst after calcination.
If the proportion of the phosphorus component is too small, the technical effect of compounding the phosphorus component will not be exhibited, and if it is too large, the pore volume of the catalyst after preparation tends to decrease too much and the catalytic activity tends to decrease (that is, Since phosphorus crushes small pores, the active sites are reduced).
[0019]
The ratio of the IIA group metal component is 0.1 to 2% by mass, preferably 0.5 to 1.5% by mass in terms of oxide, with respect to the catalyst after calcination.
If the proportion of the IIA component is too small, the technical effect of blending the IIA component will not be exhibited, and if it is too large, the acid sites of the catalyst after preparation will be poisoned, and the catalytic activity tends to decrease.
[0020]
If the amount of the solvent used is too small, the carrier cannot be sufficiently impregnated, and if it is too much, the dissolved components will not impregnate on the carrier and will adhere to the edge of the impregnation solution container, etc. In general, the amount is 50 to 150 parts by mass, preferably 70 to 90 parts by mass with respect to 100 parts by mass of the carrier.
[0021]
In the present invention, the impregnation solution prepared by dissolving the components in the solvent is sequentially impregnated with the support. At this time, the impregnation order is as follows. In the second solution, the molybdenum component was dissolved in the second stage after drying and firing. After drying and firing again, the cobalt component was dissolved in the third stage. The third solution is impregnated, and the final drying and baking are performed.
[0022]
In any of these first to third stages, various conditions can be adopted as the impregnation conditions.
For example, in any of the first to third stages, the temperature is 10 to 100 ° C, preferably 10 to 50 ° C, and more preferably 15 to 30 ° C. If the temperature is too high, drying may occur during the impregnation and the degree of dispersion may be biased.
The impregnation time is 15 minutes to 3 hours, preferably 20 minutes to 2 hours, and more preferably 30 minutes to 1 hour.
Furthermore, it is preferable to stir during the impregnation.
[0023]
Drying can be performed by various drying methods such as air drying, hot air drying, heat drying, freeze drying, etc. in any of the first to third stages.
[0024]
The firing conditions may be appropriately selected and determined in any of the first to third stages, but the temperature is preferably in the range of 400 to 500 ° C, particularly preferably in the range of 450 to 500 ° C. The time is preferably 2 to 10 hours, particularly 3 to 5 hours.
[0025]
The shape and size of the catalyst in the present invention are not particularly limited, and may be various shapes and sizes used for ordinary catalyst shapes.
For example, if the hydrocarbon oil is heavy oil, the shape is preferably a four-leaf type, and if it is a light oil, a cylindrical shape is preferable, and the size is usually preferably 1/10 to 1/22 inch.
[0026]
The catalyst according to the present invention prepared as described above is not particularly limited in specific surface area and pore volume. However, in the same manner as the above-mentioned carrier, in order to aim at deep desulfurization of a light oil fraction, The specific surface area is preferably 180 m ² / g or more, and the pore volume is preferably 0.35 to 0.60 cc / g.
[0027]
The average pore diameter of the catalyst is 70 to 80 mm, preferably 73 to 77 mm. If the average pore diameter is too large, the diffusibility of the reactants into the pores is good, but the surface of the catalyst cannot be used effectively for the reaction, and it is difficult to remove the hardly desulfurizing substances in the gas oil fraction. Become.
That is, since the deep desulfurization reaction is mainly performed by reducing the liquid space velocity due to hue and problems on the apparatus, the superiority of the catalyst having a large average pore diameter is reduced. As a result, no improvement in activity is observed.
On the other hand, if the average pore diameter is too small, the physical properties (specific surface area, pore volume) necessary for functioning as a catalyst cannot be maintained, and production is impossible.
[0028]
Further, the pore size distribution (MPD ± 15Å) of the catalyst is 70% or more, preferably 80% or more.
If the pore size distribution is broad, even if MPD is an ideal value, the number of pores effective for the reaction is relatively small, and a highly active catalyst cannot be expected.
[0029]
The catalyst according to the present invention may be mixed with a known catalyst or a known inorganic oxide support when used in an actual process.
The hydrocarbon oil to be treated with the catalyst according to the present invention includes a light fraction obtained by atmospheric distillation or vacuum distillation of crude oil, an atmospheric distillation residue, coker gas oil, solvent history oil, tar sand oil, shale oil, Examples include various hydrocarbon oils such as coal liquefied oil.
[0030]
In order to use the catalyst according to the invention in a desulfurization unit by commercial hydrotreating on a commercial scale, the catalyst according to the invention can be used as a fixed bed, moving bed or fluidized bed in a suitable reactor and treated in the reactor. What is necessary is just to introduce | transduce the oil which should be processed and to process on the conditions of high temperature high pressure and a considerable hydrogen partial pressure.
Most commonly, the catalyst according to the invention is maintained as a fixed bed so that the oil passes down the fixed bed. At this time, the catalyst can be used in a single reactor or several consecutive reactors can be used. In particular, when the feedstock is heavy, it is preferable to use a multistage reactor.
[0031]
Preferable examples of the reaction include a hydrocarbon oil in the range of about 200 to 500 ° C., more preferably 250 to 400 ° C., and a liquid space velocity of about 0.05 to 5.0 hr ⁻¹ , more preferably 0.1 to 0.1 ° C. In the range of 4.0 hr ^−1, the contact with the catalyst according to the present invention may be mentioned under the condition where the hydrogen partial pressure is about 3 to 20 MPa, more preferably 4 to 15 MPa.
Under such conditions, the life of the catalyst according to the present invention is equal to or longer than that of a typical conventional catalyst, and the catalyst according to the present invention can be used in an actual apparatus for 1 year or longer.
[0032]
The catalyst according to the present invention as described above is preferably subjected to preliminary sulfidation prior to use in the hydrotreating of hydrocarbon oil.
The preliminary sulfidation can be performed in situ in a reaction tower for hydrotreating hydrocarbon oil.
That is, the catalyst according to the present invention was mixed with a hydrogen sulfide / hydrogen mixed gas, a temperature of 100 to 400 ° C., a pressure (total pressure) of 0.1 to 5.0 MPa, and a gas space velocity of 0.3 to 2000 hr ⁻¹ . Contact in the presence of a hydrogen-containing gas of ~ 0.7 L / LH ₂ S / H ₂ , and after completion of this treatment, the hydrogen sulfide / hydrogen mixed gas is switched to the hydrotreating target oil, Set operation conditions suitable for desulfurization and start operation.
In addition to such processes, sulfur-containing hydrocarbon oils (eg sulfur-containing distillate), other sulfur compounds are contacted directly with the catalyst according to the invention, or these sulfur compounds are appropriately distilled. The presulfidation of the catalyst of the present invention can also be performed by a method of bringing the product added to the product into contact with the catalyst according to the present invention.
[0033]
【Example】
Example 1
First, the first stage of impregnation was carried out using a first aqueous solution in which 9.6 g of orthophosphoric acid and 5.86 g of calcium nitrate were dissolved in 150 g of water and stirred in an Erlenmeyer flask. ² / g, impregnating 200 g of an alumina carrier (substantially composed of γ-alumina) having a pore volume of 0.64 cc / g, impregnation was performed at 20 ° C. for 1 hour, and after drying (air drying), a muffle furnace Firing was carried out at 500 ° C. for 4 hours.
Next, in the Erlenmeyer flask, a second aqueous solution in which 67.8 g of ammonium molybdate was dissolved in 100 g of water and ammonia water was added and stirred until the ammonium molybdate was completely dissolved was used for the second stage of impregnation support. The same operation as in the first stage was performed on the catalyst intermediate subjected to the first stage impregnation and support.
The final third stage impregnation support was carried out in the same manner as in the first stage using a third aqueous solution in which 54 g of cobalt nitrate was dissolved in 90 g of water and stirred in an Erlenmeyer flask. Performed on the catalyst intermediate performed.
In this way, Catalyst A was obtained.
[0034]
Example 2
Example 1 with the exception that 7.7 g was used instead of 9.6 g of orthophosphoric acid, 101.9 g was used instead of 67.9 g of ammonium molybdate, and 32.4 g was used instead of 54 g of cobalt nitrate. Catalyst B was obtained in the same manner.
[0035]
Example 3
Example 1.9 except that 1.9 g was used instead of 9.6 g of orthophosphoric acid, 1.2 g was used instead of 5.96 g of calcium nitrate, and 76.7 g was used instead of 54 g of cobalt nitrate. Catalyst C was obtained by the method.
[0036]
Example 4
Example 1 except that 1.9 g was used instead of 9.6 g of phosphoric acid, 1.2 g was used instead of 5.96 g of calcium nitrate, and 101.9 g was used instead of 67.9 g of ammonium molybdate. Catalyst D was obtained in the same manner as above.
[0037]
Example 5
Catalyst E was obtained in the same manner as in Example 1, except that 11.52 g was used instead of 9.6 g of orthophosphoric acid and 23.8 g was used instead of 5.96 g of calcium nitrate.
[0038]
Example 6
Catalyst F was obtained in the same manner as in Example 1, except that 5.36 g of magnesium nitrate was used instead of 5.96 g of calcium nitrate.
[0039]
Example 7
43.4 g is used instead of 54 g cobalt nitrate, 61.9 g is used instead of 67.9 g ammonium molybdate, 7.7 g is used instead of 9.6 g orthophosphoric acid, and 5.96 g calcium nitrate is used. Instead, catalyst G was obtained in the same manner as in Example 1, except that 17.6 g was used.
[0040]
Example 8
64.4 g is used instead of 54 g of cobalt nitrate, 84.9 g is used instead of 67.9 g of ammonium molybdate, 3.8 g is used instead of 9.6 g of orthophosphoric acid, and 5.96 g of calcium nitrate is used. Instead, catalyst H was obtained in the same manner as in Example 1, except that 23.6 g was used.
[0041]
Example 9
43.4 g is used instead of 54 g of cobalt nitrate, 33.9 g is used instead of 67.9 g of ammonium molybdate, 7.7 g is used instead of 9.6 g of orthophosphoric acid, and 5.96 g of calcium nitrate is used. Instead, catalyst I was obtained in the same manner as in Example 1 except that 3.6 g of strontium nitrate was used.
[0042]
Example 10
Instead of 54 g of cobalt nitrate, 27.2 g of cobalt nitrate and 23.2 g of cobalt acetate are used, 3.8 g of orthophosphoric acid and 2.5 g of metaphosphoric acid are used instead of 9.6 g of orthophosphoric acid, and 5.96 g of calcium nitrate is used. Instead, Catalyst J was obtained in the same manner as in Example 1 except that 2.9 g of calcium nitrate and 1.6 g of strontium nitrate were used.
[0043]
Example 11
Catalyst K was obtained in the same manner as in Example 1, except that the impregnation of the supported component was carried out at 10 ° C. for 2 hours and calcination was carried out at 400 ° C. for 3 hours.
[0044]
Example 12
Catalyst L was obtained in the same manner as in Example 1, except that the impregnation of the supported component was performed at 30 ° C. for 20 minutes and calcination was performed at 450 ° C. for 5 hours.
[0045]
Comparative Example 1
Example 1 except that 77.8 g of ammonium molybdate impregnated in the second stage was impregnated in the first stage simultaneously with the phosphorus component and calcium component, and the remaining 50.8 g was impregnated in the second stage. Catalyst M was obtained in the same manner.
[0046]
Comparative Example 2
Catalyst N was prepared in the same manner as in Example 1 except that no phosphorus component was used, 11.9 g was used instead of 5.96 g of calcium nitrate, and 118.7 g was used instead of 67.9 g of ammonium molybdate. Got.
[0047]
Comparative Example 3
Catalyst O was obtained in the same manner as in Example 1, except that 18.7 g of orthophosphoric acid was used instead of 9.6 g, and 108 g was used instead of 54 g of cobalt nitrate.
[0048]
Comparative Example 4
The catalyst was prepared in the same manner as in Example 1 except that 11.9 g of orthophosphoric acid was used instead of 9.6 g, calcium nitrate was not used, and 27.12 g was used instead of 67.9 g of ammonium molybdate. P was obtained.
[0049]
Comparative Example 5
Catalyst Q was obtained in the same manner as in Example 1 except that 11.7 g of orthophosphoric acid was used instead of 9.6 g and cobalt nitrate was not used.
[0050]
Comparative Example 6
Catalyst R was obtained in the same manner as in Example 1, except that 7.68 g of orthophosphoric acid was used instead of 9.6 g and 47.7 g of calcium nitrate was used instead of 5.96 g.
[0051]
Using the 18 catalysts described above, activity evaluation was measured under the conditions shown in Table 1.
[0052]
[Table 1]

[0053]
Table 2 shows the composition and physical properties of the catalysts used in Examples and Comparative Examples, and reaction results (relative activity values when Comparative Example 1 is 100).
[0054]
[1 in Table 2]

[0055]
[Table 2-2]

[0056]
[Table 2-3]

[0057]
[Table 2-4]

[0058]
[Table 2-5]

[0059]
【The invention's effect】
According to the hydrodesulfurization catalyst obtained by the production method of the present invention, since both the phosphorus and group IIA metal components are contained, the desulfurization activity is very excellent, and there is a problem at a sulfur content of 0.05% by mass. This is very effective because it can sufficiently cope with desulfurization of 4M-DBT or 4.6DM-DBT, which is a difficult desulfurization substance.
In addition, the cost is not inferior to that of the conventional catalyst manufacturing method.
Thus, since the catalyst obtained by the method of the present invention can effectively produce a fuel oil having a low sulfur content, it is extremely effective in practice.

Claims (1)

A first solution containing a phosphorus component and a Group IIA metal component of the periodic table on an inorganic oxide support, 0.1 to 4% by mass of the phosphorus component in terms of P ₂ O ₅ on a catalyst basis, The second solution containing the molybdenum component is impregnated and supported so that the group IIA metal component is 0.1 to 2% by mass in terms of monoxide, dried and fired, and the molybdenum component is MoO on a catalyst basis. _After impregnating and supporting 10 to 30% by mass in terms of ₃ and drying and firing, the third solution containing the cobalt component becomes 3 to 7% by mass in terms of CoO on a catalyst basis. A method for producing a hydrodesulfurization catalyst for hydrocarbon oils, comprising impregnating and supporting, drying and calcining.