JP2577739B2 - Hydroprocessing catalyst for hydrocarbons - Google Patents

Description

The present invention relates to a hydroprocessing catalyst for hydrocracking or hydrodesulfurizing a hydrocarbon feed.

[Prior Art] Catalysts used in hydrotreating such as hydrodesulfurization and hydrocracking of hydrocarbon fractions are generally produced by supporting a metal active component on an appropriate simple substance. Since calcination is usually performed as a final step, the metal active component is present in the catalyst in the form of an oxide having poor catalytic activity. Therefore, when such a catalyst is used in a hydrocarbon hydrotreating reaction, a so-called presulfurization operation for preliminarily sulphidizing and activating a metal active component in the catalyst is required.

As this presulfurization method, a method is known in which a catalyst in which the metal active component is in the form of an oxide is charged into a reactor, and hydrogen sulfide gas and hydrogen gas are supplied to the reactor to sulfide the metal active component of the catalyst. I have. In addition, instead of hydrogen sulfide gas, a method of supplying hydrocarbon oil such as light oil and hydrogen and pre-sulfurizing the catalyst has been adopted. In addition, sulfur compounds such as carbon disulfide, dimethyl sulfide (DMS), and dimethyl disulfide (DMDS) have been added to the pre-sulfurizing hydrocarbon oil. Furthermore, as disclosed in JP-A-60-51547, a catalyst containing a metal active component is provided with an R-S
A method of impregnating (n) -R '(n = 3 to 20) with a polysulfide and heating the polysulfide to a temperature of 200 ° C. or lower in a hydrogen stream to activate (preliminary sulfurization) has also been proposed.

[Problems to be Solved by the Invention] In the above-mentioned conventional presulfurization method for a catalyst, the method using hydrogen sulfide gas has a drawback that handling is troublesome because this gas has toxicity. . Further, the method using hydrogen and hydrocarbon oil such as light oil requires a relatively long time for preliminary sulfurization of the catalyst, and also requires a large amount of hydrocarbon oil. In addition, since the catalyst must be maintained at a high temperature for a long time during pre-sulfurization, there is a concern that the original catalytic activity may be impaired. However, these problems can be solved by adding a sulfurizing agent such as carbon disulfide, DMS, and DMDS to the hydrocarbon oil. However, these sulphiding agents are generally not only expensive, but also require storage and injection into the reactor.

The polysulfide proposed in Japanese Patent Application Laid-Open No. 60-51547 has a high viscosity and must be diluted with an appropriate solvent in order to impregnate it with a catalyst.

The present invention is intended to solve the above-mentioned various problems of the pre-sulfurization method in the conventional catalyst, and does not require a special pre-sulfurization step, in other words, the catalyst is charged into a reactor and carbonized. If the temperature of the reactor is raised to the hydrogenation reaction temperature of the hydrogen supply source, the catalyst is sulfurized during the temperature rise,
Provided is a catalyst capable of causing a hydrocarbon-hydrogen treatment reaction immediately after the temperature is raised to a predetermined temperature.

[Means for Solving the Problems] However, the catalyst for hydrotreating hydrocarbons according to the present invention comprises an inert heat-resistant carrier containing a metal component of Groups VIA and VIII of the Periodic Table in one molecule. An organic sulfur compound having at least one active mercapto group and having a boiling point of 100 ° C. or higher is supported.

[Detailed Description of the Invention] In the catalyst of the present invention, the carrier component and the metal active component include Al ₂ O which is commonly used for conventional hydrocarbon hydrotreating catalysts.
_{3, SiO 2, SiO 2 -Al} 2 O 3 carrier component and the periodic table VI, such as
Group A metals and Group VIII iron group metal components are used.
Further, a metal component selected from Group IB and Group VA of the periodic table can be used in combination with the metal active component.

For example, as a catalyst for hydrotreating hydrocarbon fractions, alumina or silica-fine particles of zeolite are dispersed or supported on a support comprising a matrix having a silica-alumina degree, and a group VIA metal such as molybdenum or tungsten is used. In general, a metal of Group VIII such as iron, nickel and cobalt is supported as an oxide in an amount of 8 to 25% by weight based on the total weight of the catalyst. Can be used.

Organic sulfur compounds supported on the catalyst of the present invention,
Having at least one active mercapto group in one molecule;
Moreover, it must have a boiling point of 100 ° C. or higher. Specific examples of such organic sulfur compounds include alkyl mercaptans such as octyl mercaptan, dodecyl mercaptan, dimethylcaptopropane, dimethylcaptobutane; polyalkylene ether polythiols such as diethylene ether dithiol and triethylene ether dithiol; isooctylthio Glycolate, 2-
1 exemplified by ethylhexyl mercaptopropionate, ethylene glycol dimercaptopropionate, butanediol dimercaptoacetate, trimethylolpropanetris-mercaptoacetate, pentaerythritol tetrakis-3-mercaptopropionate, etc.
Esters of a thiocarboxylic acid with a polyhydric or polyhydric alcohol; esters of a mercapto alcohol and a carboxylic acid exemplified by mercaptoethyl acetate, dimercaptoethyl adipate; and thioethers such as diethylene thioether thiol.

The catalyst of the present invention is generally prepared by a procedure in which a suitable metal active component is supported on a suitable inert refractory support, calcined, and the organic sulfur compound of the present invention is supported thereon. Here, the steps from the step of supporting the metal active component on the carrier and calcining are not substantially different from the conventional catalyst preparation method, and this step can be employed in the present invention. For example, a method in which a metal salt to be an active species is supported on a carrier by a method such as an impregnation method or a kneading method, and then dried, molded, and calcined can be employed in the present invention. Is usually an oxide. Therefore, it is also possible to prepare the catalyst of the present invention by supporting the above-mentioned sulfur compound on a conventional hydrocarbon hydrotreating catalyst in which the metal active component is in the form of an oxide.

The method of supporting the organic sulfur compound is not particularly limited,
One of the above sulfur compounds is added to the metal oxide-containing catalyst after calcination.
It is convenient and preferable to impregnate the seed or two or more kinds by any means such as a spray method and an immersion method. In the impregnation, the organic sulfur compound can be used as it is, and it is not particularly necessary to dilute it with a solvent. Further, after the impregnation, no post-treatment such as heating is required. This is because, when the original organic sulfur compound is used, the amount of sulfur that permeates all the pores of the catalyst can sufficiently cover the amount of sulfur required to maintain the catalyst at the desired sulfuration degree. It is. Incidentally, even in the case of a hydrotreating catalyst for a hydrocarbon fraction in which a relatively high degree of sulfidity is required in a hydrocarbon hydrotreating medium, a degree of sulfidation satisfying a predetermined initial activity is obtained. The amount of sulfur required for this may be at least about 70% of the stoichiometric amount that converts all of the metal active components in the catalyst to sulfide.

Therefore, the surface of the catalyst after impregnation with the organic sulfur compound is not in a so-called "wet" state, and does not need to be particularly dried. The catalyst supporting the organic sulfur compound of the present invention does not deteriorate at ordinary environmental temperatures and does not volatilize the organic sulfur compound, so that it can be stored or transported normally.

[Action] In a conventional hydrocarbon hydrotreating process, after a reactor is filled with a catalyst, a hydrogen sulfide gas or a sulphidating agent such as a sulfur-containing hydrocarbon oil is used before supplying the raw material hydrocarbon to the catalyst. Usually, hydrogen gas is supplied to the reactor to sulfide the catalyst, but when the catalyst of the present invention is used, this preliminary sulfidation step is not required at all. That is,
As in the case of the catalytic reaction process using a catalyst that does not require pre-sulfurization, if the catalyst of the present invention is charged to a reactor and then heated to a predetermined reaction temperature, the sulfurization reaction proceeds during the temperature increase process. Then, the catalyst is sulfided. Therefore, immediately after the temperature rise of the reactor, the starting hydrocarbon can be supplied to the reactor and the target reaction can be started. In this case, the catalyst does not need to be completely sulfurized before the start of the hydrotreating reaction. Even if a part of the unsulfurized portion remains, the unsulfurized portion is also sulfided as the hydrotreating reaction proceeds.

A specific example in which the catalyst of the present invention is applied to a hydrodesulfurization method will now be described. First, a catalyst of the present invention in which an organic sulfur compound is supported on a conventional hydrodesulfurization catalyst is charged into a reactor, and then the catalyst bed is heated to about 150 to 200 ° C. while flowing an inert gas such as nitrogen into the reactor. . Next, the supply gas is switched to hydrogen, and the pressure is increased to a predetermined reaction pressure. At the same time, the temperature is increased to a predetermined reaction temperature while controlling the temperature increase rate at 15 to 30 ° C / hour. In the process so far, the hydrodesulfurization catalyst in the reactor is presulfurized and activated. Thereafter, the process parameters other than the temperature and pressure held at the predetermined values are set to the predetermined values, and the raw material hydrocarbon fraction is supplied to the reactor,
Perform the intended hydrodesulfurization treatment. It should be noted that the supply of the hydrocarbon fraction can also be started during the course of the temperature rise by the hydrogen gas. Typical hydrodesulfurization process parameters for hydrocarbon fractions include temperatures of 300-450.
° C, hydrogen partial pressure 10-200 kg / cm ² , liquid space velocity 0.1-10 hr ^-1 ,
A hydrogen / oil ratio of 100 to 2000 Nm ³ / Kl is generally employed.

The catalyst for hydrotreating hydrocarbons of the present invention can be used not only for the hydrodesulfurization method for hydrocarbon fractions described above, but also for the hydrotreating reaction for hydrocarbon hydrocracking.

[Implementation example] MoO ₃ 10.0 wt% in example _{1 Al 2 O 3, CoO 2.0wt} %, NiO 1.0wt% was prepared by a conventional method supported hydrodesulfurization catalyst.

About 720 ml of trimethylolpropane tris-mercaptopropionate was taken, and 1 kg of the above catalyst was immersed in this. The stirring was continued slowly until the sulfur compound had sufficiently penetrated into the pores of the catalyst, all of which were impregnated into the catalyst particles, and there was no "wetting" on the catalyst surface. The amount of sulfur carried on the catalyst thus obtained was 10.8 wt% as S. This catalyst is referred to as Catalyst A.

Example 2 In Example 1 as in Example 1 in the same hydrodesulfurization catalyst and method, 2-ethylhexyl-3-mercaptopropionate, diethylene thioether dithiol (SH-C ₂ H ₄ -
S-C ₂ H ₄ -SH) and dodecyl mercaptan were impregnated respectively. These are referred to as catalysts B, C and D. The amount of sulfur carried was as follows: catalyst S: 11.3 wt% for catalyst B, 21.4 wt% for catalyst C, catalyst D
Was 11.8 wt.

Example 3 The hydrodesulfurization reaction test of each of the catalysts A, B, C and D was performed as follows.
It carried out by the following method.

A high-pressure reactor having an inner diameter of 19 mm and a length of 1.8 m was filled with the catalyst, and the temperature was raised to 200 ° C. while flowing nitrogen gas. Thereafter, the nitrogen gas was switched to hydrogen gas, and the pressure was increased to 150 kg / cm ² .
Next, hydrogen gas and raw material oil were respectively 700Nm ^{3 /} hr, 1.0Kl / hr
And the temperature was raised to a predetermined reaction temperature at a heating rate of 20 ° C./hour.

After reaching the predetermined reaction temperature, LHSV 0.2 hr ^-1 , hydrogen /
The reaction test was carried out while maintaining steady conditions of an oil ratio of 700 Nm ³ / Kl and a hydrogen partial pressure of 150 kg / cm ² .

The properties of the atmospheric distillation residue used as the feedstock are shown below.

Specific gravity (15/4 ° C) 0.960 Viscosity (50 ° C) 4.53 cst Sulfur 2.283wt% Nitrogen 2220ppm Asphaltene 2.1wt% Conradson carbon 9.9wt% Metal (Ni + V) 70ppm Example 4 Catalyst A in one reactor with Example 3 After filling, the temperature was raised to 180 ° C. while flowing nitrogen gas, the nitrogen gas was switched to hydrogen gas, and the pressure was increased to 150 kg / cm ² . Then, while supplying hydrogen gas to the reactor at 700 Nm ³ / hr, the temperature was raised to a predetermined reaction temperature at a temperature rising rate of 20 ° C./hour. Thereafter, under the same steady-state conditions as in Example 3, a hydrodesulfurization reaction test of the same feedstock oil as in Example 3 was performed.

Comparative Example The hydrodesulfurization catalyst prepared in Example 1 was charged into the same reactor as in Example 3 without supporting a sulfur compound, and heated to 180 ° C. while flowing nitrogen gas. The gas was switched to hydrogen gas, and the pressure was increased to 150 kg / cm ² . Thereafter, hydrogen gas and light oil were each supplied at 400 Nm ³ / hr, 1.
The temperature was raised to 280 ° C. at a rate of 30 ° C./hour while flowing at 0 Kl / hr. Next, the temperature of 280 ° C. was maintained for 48 hours to carry out preliminary sulfurization of the catalyst.

After completion of sulfurization, the light oil was switched to the feedstock oil used in Example 3, and the temperature was raised to a predetermined reaction temperature at a rate of 30 ° C./hour, and a hydrodesulfurization reaction test was performed under the same conditions as in Example 3. did.

 Table 1 shows the experimental results of Examples 3 and 4 and Comparative Example.

As is evident from the results shown in Table 1, the hydrodesulfurization catalyst of the present invention exhibits catalytic performance equivalent to or superior to that of the hydrodesulfurization catalyst preliminarily sulfided by the conventional method without performing any preliminary sulfidation operation. I do.

[Effects of the Invention] The catalyst of the present invention can sulfidize and activate the catalyst in the process of raising the temperature of the catalyst bed at the start of a normal hydrotreating reaction, so that the catalyst can be used as in the prior art. There is no need to provide a special presulfurization step. Therefore, it is possible to shorten the time until the start of the reaction, and furthermore, since a sulfurizing agent such as light oil for sulfurization is not required, the use of the catalyst of the present invention reduces the cost required for hydrotreating hydrocarbons. Advantages such as significant savings can be obtained.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Yoichi Nishimura 3016-1-911, Nagatsutacho, Midori-ku, Yokohama-shi (72) Inventor Nagahisa Omiwa 3-19-9, Nukii, Nerima-ku, Tokyo (56) References 1970-401541 (JP, B1)

Claims (1)

(57) [Claims] (1) an inert heat-resistant support having a metal of Group VIA and a metal of Group VIII of the periodic table and at least one active mercapto group in one molecule; A catalyst for hydrotreating hydrocarbons, which carries an organic sulfur compound.