JPH0483536A - Method for producing hydroprocessing catalyst for hydrocarbon oil - Google Patents

Abstract

PURPOSE:To obtain a hydrogenating catalyst having a sulfurizing agent thorough ly and uniformly dispersed therein and suppressed in the deterioration of cata lytic activity by holding a catalyst impregnated with the sulfiding agent to a specific temp. range while keeping the moisture thereof to a specific range. CONSTITUTION:A sulfurizing agent such as mercaptocarboxylic acid is infiltrated in a carrier such as alumina or titania having an element such as Mo or W of the Group VI of the Periodic Table and an element such as Co or Ni of the Group VIII of the Periodic Table supported thereon. Thereafter, the impreg nated carrier is allowed to stand at 40-170 deg.C in such a state that the moisture of a catalyst is held to 5-50wt.%. By this method, the sulfiding agent can be uniformly dispersed throughout the catalyst from the outer surface thereof to the interior thereof and, therefore, a hydrogenating catalyst having high activity and keeping said activity is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a catalyst for hydrotreating hydrocarbon oil with little activity deterioration and a method for producing the same.

(Conventional technology) Desulfurization of petroleum hydrocarbon oils such as light oil and heavy oil in the presence of hydrogen.
In so-called hydrogenation treatment that performs denitrification, hydrogenation, decomposition, etc., No and W from group 6 of the periodic table and Co and N from group 8 of the periodic table are added to an inorganic oxide support such as alumina, titania, and silica.
Catalysts supporting i are often used.

However, conventionally, regarding this hydrodesulfurization catalyst,
Broadly speaking, two problems have been pointed out, the first of which is the presulfiding operation, and the second is related to deterioration of activity.

To explain the first presulfidation, the metal supported on the carrier is usually supported in the form of an oxide, and since it is not active as it is, it is necessary to
A pre-sulfurization step is essential to convert and activate the oxide state into the sulfide state.

Conventionally, the so-called on-site sulfurization method involves filling a hydrocarbon oil hydrotreating equipment with a catalyst, and then passing the hydrocarbon oil with a sulfurizing agent dissolved in the catalyst layer in the presence of hydrogen and sulfurizing it by raising the temperature. law is commonly practiced.

However, in the on-side sulfiding method, the preliminary sulfiding operation determines the success or failure of the subsequent hydrogenation treatment, so appropriate selection of materials and careful operation are required. For example, when using a diluent, if the diluent contains olefins, it is necessary to use a hydrocarbon oil that does not contain olefins to prevent the polymerization product from poisoning the catalyst. If it is too high, the wetting effect on the surface of the catalyst will be poor and heavy oil will be unsuitable, so in the end, light oil will have to be used. Furthermore, the active metal reacts with hydrogen at high temperatures and becomes reduced and passivated, reducing the catalytic activity. Therefore, in order to prevent this, it is necessary to use a large amount of sulfurizing agent. As described above, in the on-site sulfurization method, a preliminary sulfurization step is essential and complicated, and careful operation is required in all respects. Therefore, it has been an issue to omit this presulfurization step, or at least reduce its complexity.

Recently, an off-site sulfurization method has been proposed as a new method that can meet these demands. That is, the method involves pre-impregnating and supporting a sulfurizing agent on a catalyst supported with an active metal, adsorbing the sulfurizing agent into the catalyst, or forming a coordination compound with the active metal. This is a method of containing and retaining sulfur content, and the hydrotreating operation can be started immediately by filling the catalyst into a hydrotreating apparatus and raising the temperature. With the establishment of this off-site sulfurization method, the troublesome preliminary sulfurization step that was performed in the on-site sulfurization method can be omitted, and the catalyst can now be activated with a simple operation.

Next, to explain the second problem, activity, currently in Japan, the sulfur content is reduced from 0.3 to
The sulfur content in diesel oil has been reduced to 0.4% by weight and used for automobile fuel, etc., but recently the Central Pollution Control Council has decided to reduce the sulfur content in diesel oil to the current 0.5% by weight (JIS 2204).
A proposal was made to gradually reduce the amount from 0.2% by weight to 0.05% by weight. However, the conventional catalysts described above cannot satisfy this requirement, and if a conventional catalyst were to be used to meet this requirement, a desulfurization operation using a considerable number of stages would be required.
It is clear that a significant increase in costs will be inevitable. Against this background, there is a strong desire to develop hydrodesulfurization catalysts that are much more active than conventional catalysts.

Therefore, the present applicant previously proposed a hydrogenation treatment catalyst using mercaptocarboxylic acid as a sulfiding agent and a method for producing the same in order to solve the above-mentioned two problems. Since the mercaptocarboxylic acid forms a stable coordination compound with the active metal in the catalyst, the sulfur content can be easily supported in the catalyst, and the first problem described above can be solved. Furthermore, mercaptocarboxylic acid has the effect of significantly increasing the activity of the hydrotreating catalyst, and the second problem, the activity, is also improved.

(Problems to be Solved by the Invention) However, although the catalyst using mercaptocarboxylic acid as a sulfiding agent has high activity, there is a problem in that the high activity is not maintained for a long period of time and the activity deteriorates. That is, the catalyst exhibited extremely high activity at the initial stage of the reaction, but as the reaction time progressed, the activity was found to decrease to the same level as the activity of conventional catalysts at the early stage of the reaction.

The present invention aims to solve the above-mentioned problems by providing a hydrotreating catalyst that can suppress the deterioration of the activity of a catalyst produced by an off-site sulfurization method using a sulfurizing agent such as mercaptocarboxylic acid, and a method for producing the same. It is something to do.

(Means for Solving the Problems) As a result of intensive research to solve the above problems and achieve the above objects, the present inventors have discovered that while maintaining the moisture content of a catalyst impregnated with a sulfiding agent within a specific range, The present invention was completed based on the discovery that the object could be achieved by maintaining the temperature within a specific range to form a catalyst in which the sulfiding agent was uniformly dispersed throughout the catalyst.

That is, the first embodiment of the present invention is a hydrocarbon oil hydrotreating catalyst in which a sulfiding agent is uniformly supported from the outer surface to the inside of the hydrotreating catalyst, and the second embodiment is
After impregnating a sulfiding agent into a hydrocarbon oil hydrotreating catalyst supporting metals of Groups 6 and 8 of the periodic table,
40° to 170' while maintaining 50% moisture
This is a method for producing a catalyst for hydrotreating hydrocarbon oil, which is left in a temperature range of C.

(Function) Examples of the carrier in the present invention include common porous materials such as alumina, titania, silica, and activated carbon, and in particular, aluminium, alumina-silica, etc. are commonly used.

As the Group 6 metals of the periodic table, No and W are used, and as the Group 8 metals, Co and Ni are used, and these include ammonium molybdate, ammonium tungstate,
Cobalt nitrate, cobalt carbonate, nickel nitrate, and nickel carbonate are used as water-soluble compounds, and molybdenum trioxide and tungsten trioxide can also be used as ammonium molybdate and ammonium tungstate, respectively, using ammonia gas. The compounds are those that form sulfides such as Ho52, WS2, CO3, and NiS that exhibit high activity in hydrodesulfurization reactions with mercaptocarphonic acid.

Preferred examples of the sulfurizing agent include mercaptocarboxylic acids such as mercaptoacetic acid (H3CH2.C00H) and p-mercaptopropionic acid (H3CH2CH2COOH).

The amount of mercaptocarboxylic acid used as a sulfiding agent is determined by the amount of sulfide in which molybdenum, tungsten, cobalt, and nickel exhibit high activity in hydrogenation reactions (e.g., MoS).
2. Oka. , CoS, NiS) is preferably 1 to 3 times the amount of sulfur required to form sulfur.

If the amount used is less than this, the activity will decrease, and even if more than this amount is used, no significant improvement in activity can be expected, so it is uneconomical.

In addition, phosphorus is also a conventionally known active substance,
It can also be used in the present invention, and phosphoric acid is suitable as the impregnating form. This phosphoric acid may be impregnated as a separate aqueous solution from the water-soluble compound, or may be impregnated simultaneously using an impregnating solution containing both the water-soluble compound.

In the case of simultaneous impregnation, as the content of phosphoric acid increases, the liquid viscosity increases and impregnation becomes difficult.

Therefore, in this case, the limit is approximately 8% by weight of P2O5 supported in the catalyst.

- The method for producing a numerical hydrocarbon oil hydrotreating catalyst consists of the steps of impregnating a carrier with an aqueous solution of an active metal, drying it, and then calcining it. Either a mercaptocarboxylic acid solution is directly supported on the dried product after impregnating with an aqueous solution of an active metal and phosphoric acid, if necessary, separately or simultaneously, or a water-soluble compound of an active metal is added to the carrier. A mercaptocarboxylic acid solution is supported by an impregnation method.

After impregnating the catalyst with sulfide, the catalyst may be left to age at a temperature of 40° to 170° C. while maintaining a moisture content of 5 to 50% by weight. However, the reason for these numerical limitations is that if the moisture content is less than 5% by weight, the penetration of the sulfurizing agent will be slow and not uniform, making it inefficient, and if it exceeds 50% by weight, active metals will be eluted, and if left unattended. If the temperature is below 40°C, the penetration of the sulfurizing agent will be slow and not uniform, making it inefficient.
This is because when the temperature exceeds 70°C, sulfides are easily decomposed.

Note that since the standing time has a correlation with the temperature, it is preferable to obtain it in advance.

In the method of the present invention, specific methods for maintaining 5 to 50% by weight of water in the catalyst include leaving it in steam, separating the impregnating liquid and the carrier with a screen, and then leaving it at room temperature. Generally, 5 to 50
Other methods may be used as appropriate provided the weight percent moisture is maintained.

Since the catalyst of the present invention is produced in this manner, the sulfur content is uniformly distributed in the catalyst matrix.

EP of sulfur in the cut plane of the catalyst of the present invention and the conventional catalyst
The measurement results of the HA profile are shown in FIG. From this, it can be seen that the sulfur distribution state of the catalyst of the present invention is significantly different from that of the conventional catalyst, and sulfur is uniformly distributed throughout the catalyst.

The reason why the activity of the catalyst of the present invention does not deteriorate over a long period of time is not clear, but by leaving the catalyst in the presence of moisture and aging it, the sulfiding agent penetrates into the inside of the catalyst or into the micropore area. In order for the sulfiding agent to diffuse and stabilize the active metal species supported in the catalyst,
It is thought that as a result, aggregation of the active metal was suppressed and deterioration of activity was suppressed.

(Example) Next, examples of the present invention will be described.

Example 1 Specific surface area 280 rri'/g, pore volume 0.75+n
e/g of γ-alumina support, 24.0 g of molybdenum trioxide, 8.5 g of cobalt carbonate, 85% phosphorus M6.
It was impregnated with some active metal aqueous solution prepared from 4g and water and dried at 110°C for 10 hours. Next, after impregnating the dried product with 60.0 g of mercaptoacetic acid, under saturated steam,
40. The catalysts A, B,
It was set as C.

The metal content of catalysts A to C is 18% by weight of molybdenum as HoO3, 4% by weight of cobalt as Coo, and 3% by weight of phosphorus as F2O3. , CoS
It was 1.35 times the theoretical amount of sulfur required to achieve this.

Using these catalysts A, B, and C, a hydrodesulfurization reaction of Kuwait atmospheric gas oil was carried out. The properties of the atmospheric gas oil used in the reaction were as follows.

Specific gravity (15/4℃) 0.844 sulfur
Yellow (weight%) 1°55 Distillation properties (initial boiling point, °C) 231 (50voj%, 'C) 3
13 (End point, °C) 390 The reaction was carried out using a flow reactor under the following reaction conditions.

Catalyst amount (me> 15 Raw oil liquid hourly space velocity (hr”) 2 Reaction hydrogen pressure (
1 odor G) 30 Reaction temperature ("C) 330 Hydrogen/oil flow ratio (N, ll/I) 3o.

Oil passing time (hr) aa Table 1 shows the evaluation results of hydrodesulfurization activity after reaction time of 16 hours and 88 hours.

Comparative Example: To 100 g of the above γ-alumina carrier, 2 molybdenum trioxide was added.
40g, cobalt carbonate 8.5g, 85% phosphoric acid 6.4g
and 80 J of an active metal aqueous solution prepared from water.
It was dried at 10'C for 10 hours. Next, the dried product was impregnated with 60.0 g of mercaptoacetic acid, and then immediately heated to 110°C for 1 hour.
It was dried for 0 hours to form a catalyst.

The metal content of the catalyst is 18% by weight in terms of molybdenum or HoO3, 4% by weight of cobalt in terms of CoO,
Phosphorus is 3% by weight in terms of P2O5, and the amount of mercaptoacetic acid added is 8052% for Ha and Co, and 8052% for Co, respectively.
The theoretical amount of sulfur required to reach oS is 1.35
It was double that.

An activity evaluation test was conducted in the same manner as in Example 1 using this catalyst. The results are shown in Table 1.

Table 1: The desulfurization rate after 16 hours of the catalyst prepared by the conventional method is slightly higher than that of catalysts A, B, and C of the present invention; are catalysts A and B
It was observed that the desulfurization rate was significantly lower than that of , C, and the superiority of the catalyst of the present invention is clear.

Example 2 A dried product obtained using the same carrier and aqueous solution as in Example 1 was impregnated with 60.0 g of mercaptoacetic acid, and then the same three types as in Example 1 were added in a closed container instead of the saturated steam in Example 1. The mixture was left at a temperature of 100° C. for 10 hours, and then dried at 100° C. for 10 hours to obtain catalysts E, F, and G.

The metal content and the amount of mercaptoacetic acid added in these catalysts E to G were the same as in Example 1.

Using these catalysts E to G, a hydrodesulfurization reaction was carried out under the conditions shown in Example 1 with the properties shown in Example 1.

The evaluation results of hydrodesulfurization activity after reaction times of 16 hours and 88 hours were significantly better than those of catalysts A to C.

Example 3 Molybdenum trioxide 2 was added to 100 g of the γ-alumina carrier.
4.0g, cobalt carbonate 8.5g, 85% phosphoric acid 6.4
The active metal solution prepared from g and water was impregnated with 80+ne and dried at 110'C for 10 hours. Next, to the dried product,
After impregnating 70 g of α-mercaptopropionic acid,
The mixture was left to stand for 0 hours, and then dried at 110°C for 10 hours to obtain catalysts H1 and J. The metal contents of these catalysts H to J are as follows: molybdenum is 18% by weight as HoO, cobalt is 4% by weight as Coo, and phosphorus is 3% by weight as F2O3.
Yes, the amount of mercaptopropionic acid added is No.
The amount was 1.35 times the theoretical amount of sulfur required for Co to become HoS and CoS, respectively.

Regarding these catalysts H to J, an activity evaluation test was conducted in the same manner as in Example 1. The results were approximately the same as those of catalysts A to C.

Example 4 Pseudo-boehmite alumina carrier (Af20392.8% by weight
) was impregnated with 80 J of an active metal aqueous solution prepared from 24.0 g of molybdenum trioxide, 8.5 g of cobalt carbonate, 6.4 g of 85% phosphoric acid, and water, and dried at 110'C for 10 hours. Next, add mercaptoacetic acid 6 to the dried product.
0. After impregnating with Og, under saturated steam, 40.100.
Leave for 10 hours at three different temperatures of 150℃, then 11
After drying at 0'C for 10 hours, L and M were obtained as catalysts. These catalysts have a metal content of ~L, with molybdenum being MoO
18% by weight as 3, 4% by weight as cobalt
, phosphorus is 3% by weight as F2O3, and the amount of mercaptoacetic acid added is Ho52 and Co, respectively.
It was 1.35 times the theoretical amount of sulfur required to become S.

An activity evaluation test was conducted on these catalysts in the same manner as in Example 1 for -L. The results were approximately the same as those of catalysts A to C.

(Effects of the Invention) The present invention allows the catalyst to be left to mature at a specific temperature while maintaining a specific range of moisture, thereby obtaining a hydrotreating catalyst with less activity deterioration than conventional catalysts. This has made it possible to do this, and it has been found to have extremely significant effects.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the measurement results of the EP)IA profile of sulfur on a cut surface. Figure 1

Claims (1)

[Scope of Claims] 1) A catalyst for hydrotreating hydrocarbon oil, characterized in that a sulfiding agent is uniformly supported from the outer surface to the inside of the hydrotreating catalyst. 2) After impregnating a sulfiding agent into a hydrocarbon oil hydrotreating catalyst carrying metals from Groups 6 and 8 of the periodic table, while maintaining 5 to 50% by weight of water in the catalyst, 40°～17
A method for producing a catalyst for hydrotreating hydrocarbon oil, which comprises leaving it in a temperature range of 0°C.