JP2863559B2 - Activation method of sulfide precursor type hydrotreating catalyst - Google Patents

Description

The present invention is used for hydrodesulfurization of hydrocarbon oils.
The present invention relates to a method for activating a sulfide precursor-type hydrotreating catalyst containing an organic sulfur compound as a sulfide.

[Prior Art] In general, catalysts used for hydrodesulfurization of hydrocarbon oils include inorganic oxide carriers such as γ-alumina and silica-alumina, and metals selected from Group 6 and Group 8 metals in the periodic table. Which carry at least one kind of metal as a hydrogenation active component. Most commonly, molybdenum is used as the Group 6 metal and nickel or cobalt is used as the Group 8 metal. Since these metal active components are usually supported in an oxide state after preparation and are not active as they are, pre-sulfurization, which converts from an oxide state to a sulfide state in order to be subjected to a hydrotreating reaction, is called an active state. Is necessary. As this activation method, a method is generally employed in which hydrogen sulfide is mixed with an organic sulfur compound such as mercaptans in light oil and then flows through a fixed catalyst layer.

[Problems to be Solved by the Invention] However, these methods have a drawback that the time required for sulfuration to completely progress is several days, and it is difficult to determine the end of sulfuration. Moreover, since the sulfidation operation is a primary operation, it is often not automated, and a complicated operation different from the usual operation is required.

Recently, a sulfurization method which is more efficient than these sulfurization methods is disclosed in JP-A-61-111144. That is, this is a method in which an organic sulfur compound represented by the following structural formula is added to an oxide type catalyst in advance to prepare a sulfurized precursor.

(Ditertiary nonyl porsulfide) Here, n is an integer of 4-20.

The organic sulfur compound is added in a necessary amount such that the active metal in the catalyst becomes almost sulfide, and is heated only to a temperature close to the desulfurization reaction temperature and the reaction raw material oil is passed only through the catalyst layer to raise the temperature. Active ingredients can be sulfurized,
This enables the desulfurization operation to be started in a short time.

 This activation method is specifically described as follows.

First, pressurize H ₂ to maintain the reactor and conduct an airtight test. This test is usually performed at 150 to 250 ° C. to avoid hydrogen embrittlement of the reactor. Next, the circulation of the reaction raw material is started. Depending on conditions, the feedstock may be circulated. The rate of temperature rise of the catalyst layer performed in this manner is about 0.3 ° C./min as a normal average value. Therefore, assuming that the hydrodesulfurization reaction temperature is 330 ° C., the time required for raising the temperature is 4.4 to 10 hours.

However, the sulfide precursor type hydrotreating catalyst was activated according to the actual refinery equipment and operating conditions as described above,
When the hydrodesulfurization reaction is carried out, there arises a problem that the initial activity of the catalyst is not sufficiently exhibited. The low initial activity of the catalyst results in a low catalytic capacity, and therefore, there is a need for the development of an appropriate activation method using a sulfide precursor type hydrotreating catalyst.

An object of the present invention is to provide an appropriate method for activating a sulfide precursor-type hydrotreating catalyst.

[Means for Solving the Problems] The present inventors have investigated the effects of various conditions applied during operation in a refinery on the desulfurization activity and found that the rate of temperature rise during activation greatly affects the desulfurization activity. As a result of repeated heading and further studies, the present invention has been achieved.

That is, the method of the present invention for solving the above-mentioned problem comprises an off-site sulfurizing agent on an alumina-supported catalyst containing at least one metal selected from Group 6 metals and Group 8 metals as a hydrogenation active component. A method for activating a sulfide precursor-type hydrodesulfurization catalyst prepared by containing
The rate of temperature rise of the catalyst layer from at least 150 ° C. to the temperature at which the active component starts a sulfurization reaction is 0.5 ° C./min or more.

[Action] The present invention relates to a sulfide prepared by adding an off-site sulfide agent to an alumina-supported catalyst containing at least one metal selected from Group 6 metals and Group 8 metals of the periodic table as a hydrogenation active component. The process for activating the product precursor type hydrodesulfurization catalyst, and first, the process of sulfurization of the active metal which proceeds with the decomposition reaction of the sulfurizing agent will be described.

 The sulfurizing agent that is an organic sulfur compound is represented as follows.

 Mercaptans: R-S-H Sulfides: R-S-R 'wherein R and R' are alkyl groups.

The decomposition of the sulfurizing agent and the sulfidation reaction are as follows.

2R-SH + Mo (IV, VI) = MoS 2 + hydrocarbons 2R-S-R '+ Mo (IV, VI) = formation reaction of MoS ₂ + molybdenum sulfide by hydrocarbon sulfurization reaction is from about 300 ° C.
, And it is well known that the higher the temperature, the more it is accelerated. On the other hand, most organic sulfur compounds used as sulphiding agents have a decomposition temperature of about 150 to 200 ° C. Therefore, when the temperature is in the range of 150 to 300 ° C., the sulfur generated by the decomposition of the sulfide agent is desorbed as hydrogen sulfide or mercaptan without sulfide of the active metal.

In the present invention, the temperature of the catalyst layer is at least 150 ° C. and the rate of temperature increase from the start temperature of the hydrotreating reaction is 0.5 ° C./min.
The reason for the above is that at 150 ° C. or higher, most of the sulphidating agents that can be used are stable and do not decompose.
The reason is that the efficiency of sulfurization is not improved at all when the temperature rise rate is less than min. Needless to say, the higher the heating rate, the more preferable. However, in reality, there is the capacity of each apparatus used, and this is the upper limit. The temperature at which the active ingredient starts to sulfurize is approximately 300 ° C., although the active ingredient differs.

[Example] 29.0 g of molybdenum trioxide, 12.5 g of cobalt carbonate, 16.5 g of 85% orthophosphoric acid, 24.1 g of mercaptoacetic acid having a purity of 85% and 14
0 g of pseudo-boehmite was kneaded with water, molded into a cylindrical shape having a diameter of 2 mm, and dried in air at 100 ° C. for 18 hours.
The sulfide precursor type hydrotreating catalyst was obtained by cutting so that the average axis length became 3 mm.

Next, into a reaction tube having an inner diameter of 1.5 cm, the filling volume was 15 cc.
The catalyst was charged so that After connecting the reaction tube flow system reactor, flows through the hydrogen pressure 30kg / cm ² -G, a hydrogen flow linear velocity 150 cm / hr, and circulated Kuwait atmospheric gas oil in the space-time rate of 4hr ^-1 at the same time. The temperature of the catalyst layer is 3
The temperature was raised at a rate of 0.83 ° C./min until the temperature reached 00 ° C., and then the hydrogen desulfurization reaction was started under the following conditions.

Space velocity during oil passing (LHSV) 2 hr- ¹ Hydrogen pressure 30 kg / cm ² -G Hydrogen flow direction linear velocity 150 cm / hr Reaction time 48 hours Reaction feedstock Kuwait normal pressure light oil (Sulfur content 1.55%) Hydrodesulfurization reaction As a result, the average desulfurization activity rate
8.5 is shown as the rate constant obtained for the 1.75 order.
This value is the average heating rate of 0.2
Higher than when the temperature was raised at ℃ / min, approx. 30%
Was also expensive.

[Comparative Example] The same catalyst as in Example 1 was filled in a similar reaction tube and connected to a flow-type reaction apparatus. Then, the hydrogen pressure was set to 30 kg / cm ¹ -G, and the hydrogen flow rate was set to 150 cm / hr. While introducing hydrogen, Kuwait normal-pressure light oil is converted to a space-time velocity (LHSV) of 4hr _-1
Then, the temperature was raised to 330 ° C. at a rate of 0.20 ° C. min, which is the average temperature rising rate in a normal refinery, and a hydrodesulfurization reaction was subsequently performed under the following conditions.

Space velocity during oil passing (LHSV) 2 hr- ¹ Hydrogen pressure 30 kg / cm ² -G Hydrogen flow direction linear velocity 150 cm / hr Reaction time 48 hours Reaction feedstock Kuwait normal pressure light oil (Sulfur content 1.55%) Hydrodesulfurization reaction As a result, the average desulfurization activity rate
5.9 was shown as the rate constant determined for the 1.75 order.
This value was about 30% lower than that of the example. This seems to have been affected by the prolonged heating.

[Effects of the Invention] As described above, according to the method of the present invention, a complicated and prolonged sulfidation operation can be completed in a short time and a simple procedure by including a sulfurizing agent off-site, and furthermore, the catalyst The initial activity of the catalyst can be increased because the loss of sulfur that can be used for sulfurization for rapidly raising the temperature can be minimized, and as a result, high desulfurization activity can be obtained.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B01J 27/04 B01J 37/20

Claims (1)

(57) [Claims] 1. A sulfide precursor prepared by incorporating an off-site sulfurizing agent into an alumina-supported catalyst containing at least one metal selected from Group 6 metals and Group 8 metals as a hydrogenation active component. In the method for activating a solid-state hydrodesulfurization catalyst, the temperature of the catalyst layer is at least 0.5 ° C.
A method for activating a sulfide precursor-type hydrotreating catalyst which is set to not less than min.