JPH06106063A - Production of catalyst for hydrogenation treatment - Google Patents

Abstract

PURPOSE:To prevent the longitudinal craze and crack of the catalyst and to greatly improve the yield of the catalyst while maintaining desulfurization and denitrification activity by confining the nitrate ions in a carrier liquid to a prescribed ratio or below. CONSTITUTION:The carrier liquid is prepd. by adding and dissolving an ammonium salt of group VIB metal elements into an aq. soln. of citric acid and further dissolving a group VIII iron family metal element salt therein. The amt. of this citric acid is required to be >=0.8mol per 1mol group VIB metal element. In addition, the carrier liquid is so prepd. as not to contain >=1wt.% nitrate ions per 100 pts.wt. alumina carrier. The carrier liquid contg. this active component is adjusted in concn. with water so as to comply with the water absorption quantity of the carrier and impregnating the alumina carrier with this liquid. As a result, the generation of the longitudinal crack and craze in the catalyst in the process of calcining the catalyst and the excess decrease in the yield of the catalyst are prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a catalyst for hydrotreating a hydrocarbon oil, particularly a catalyst for hydrodesulfurizing a heavy oil.

[0002]

2. Description of the Related Art As a hydrotreating catalyst, generally used is an alumina or silica-alumina carrier on which an active component selected from Group VIB metal elements and Group VIII iron group metal elements of the periodic table is carried. However, in recent years, a material in which phosphorus is carried as the third component has started to be adopted because of its high hydrotreating activity. This kind of catalyst
Generally, an aqueous solution in which a salt of a Group VI metal element and a salt of a Group VIII iron group metal element are dissolved is prepared, and phosphorus is added to one of these aqueous solutions to prepare two types of supporting liquids. It was prepared by impregnating an alumina carrier with the liquid, drying and firing. This is because when the above-mentioned active ingredient is prepared in one solution, the stability of the carrier solution is poor and the activity of the obtained catalyst is not improved.

By the way, when a hydroxy acid such as citric acid is added to the carrier solution in the preparation of the catalyst, the stability of the carrier solution is improved, and the active component is supported in a highly dispersed state on the carrier, and the activity of the catalyst is increased. Is known to improve (see, for example, Japanese Examined Patent Publication No. 3-72344), and a solution of a salt of a Group VI metal element, a salt of a Group VIII iron group metal element, and phosphorus in one solution is supplemented with citric acid. A method using an added carrier liquid has been proposed (Japanese Patent Laid-Open No. 2-14745).

However, the use of this supporting liquid containing citric acid has a problem that many catalyst pellets are vertically split and broken during the calcination of the catalyst, resulting in a marked decrease in the yield of the final catalyst. Further, in order to prevent this vertical cracking, the amount of the active ingredient supported must be reduced, and the hydrotreating activity must be sacrificed.

[0005]

DISCLOSURE OF THE INVENTION The present invention is to solve the above-mentioned problems, and the object of the present invention is to provide all of the active ingredients in 1
Supported by using a supporting liquid that is stably contained as a liquid,
Remarkably reduces vertical cracking while maintaining high activity,
It is an object of the present invention to provide a method for producing a hydrotreating catalyst having an improved catalyst yield.

[0006]

Means for Solving the Problems As a result of intensive research to solve the above problems, the present inventors have found that the cause of the vertical cracks during firing is to carry a Group VIII iron group metal element. It was found that vertical cracking of the catalyst can be prevented by controlling the amount of nitrate ion in the carrier liquid to be not more than a predetermined amount in the nitrate salt used for.

That is, the present invention has been made on the basis of the above findings, and is based on at least one ammonium salt selected from Group VIB metal elements of the periodic table, a phosphorus component, and a group VIII iron group metal element of the periodic table. At least one selected salt and at least 0.8 mol of citric acid per mol of the Group VIB metal element of the periodic table, and 1% by weight or more of nitrate ion based on 100 parts by weight of the alumina carrier. A solution containing no alumina is impregnated into an alumina carrier, dried, and calcined. In particular, 5 to 15% by weight of a VIB metal element of the periodic table and 1 to VIII iron metal of the periodic table in the final catalyst composition are contained. ˜5% by weight and phosphorus at 0.7 to 3% by weight, which is a method for producing a hydrotreating catalyst.

In the production of the catalyst of the present invention, first, an aqueous solution of citric acid is prepared, an ammonium salt of a Group VI metal element is dissolved therein, and then a phosphorus component is added and dissolved in this solution. Finally, it is particularly preferable to prepare the supporting liquid by a method of dissolving the Group VIII iron group metal element salt, because a stable supporting liquid can be obtained.

The amount of citric acid dissolved in the above supporting liquid is
0.8 mol or more is required for 1 mol of the Group VIB metal element. If the amount of citric acid added is smaller than this, a part of the active ingredient precipitates, and it is not possible to obtain a stable loading solution that can be uniformly loaded on the carrier.

The Group VIB metal element is selected from chromium, molybdenum, tungsten and the like, and may be used alone or in combination of two or more, and ammonium salts thereof are used. Particularly, it is preferable to use ammonium dimolybdate and ammonium heptamolybdate. The addition amount of this Group VIB metal element is determined in consideration of the water absorption amount of the alumina carrier so that it can be impregnated and supported on the alumina carrier in a total amount of 5 to 15% by weight of the metal element of this group. Is preferred.

As the phosphorus component, various phosphorus compounds can be used, but orthophosphoric acid is preferable because it is simple and convenient. The addition amount of this phosphorus component is preferably such that 0.7 to 3% by weight of phosphorus element can be supported on the alumina carrier.

The Group VIII iron group metal includes nickel, cobalt, copper and the like, and nickel and cobalt are particularly preferable. These metals may be used alone or in combination of two or more kinds. As the salt of this metal, it is preferable to use acetate, formate or carbonate because the amount of nitrate ions in the supporting liquid is reduced. The amount of the Group VIII iron group metal added is preferably 1 to 5% by weight as the total amount of the metal elements of the group so that it can be supported on the alumina carrier.

The supporting liquid supported by the above method preferably contains no nitrate ions at all, but the alumina carrier 1
When the amount of nitrate ion is 1% by weight or less with respect to 00 parts by weight, vertical cracking does not occur in the catalyst during the process of calcining the catalyst, and the yield of the catalyst does not extremely decrease.

The concentration of the supporting liquid containing the above-mentioned active ingredient is appropriately adjusted with water according to the amount of water absorption of the carrier, and the carrier is impregnated with an alumina carrier. This impregnation may be performed once, for example, by dividing the supporting liquid into two or more and repeating impregnation and drying, and may be performed plural times.

As the above-mentioned alumina carrier, one made of γ-alumina which is widely used as a catalyst can be used.

The alumina carrier after the impregnation is at room temperature to 150.
After drying at 0 ° C, preferably 100-130 ° C for 0.5 hours or more, 350-800 ° C, preferably 450-
It can be prepared as a catalyst by calcining at 600 ° C. for 0.5 hour or more.

In this catalyst, the Group VI metal element in the final catalyst composition is preferably 5 to 15% by weight. If it is less than 5% by weight, the desulfurization activity is not sufficiently exhibited. Further, even if the amount exceeds 15% by weight, the activity is not significantly improved, and the economic merit is rather small, which is not preferable. Further, the Group VIII iron group metal element is preferably 1 to 5% by weight in the final catalyst composition. 1% by weight
If it is less than 5, the effect as a co-catalyst is not sufficiently exerted and 5
Even if the amount is increased in excess of weight%, the activity is not significantly improved, which is economically unfavorable. Further, phosphorus is preferably in the range of 0.7 to 3% by weight in the final catalyst composition. If it is less than 0.7% by weight, a stable carrier liquid cannot be obtained, and if it exceeds 3% by weight, the activity is not significantly improved, which is economically not preferable.

The catalyst prepared by such a method is a catalyst for hydrotreating hydrocarbon oils, in particular, atmospheric distillation residue oil of crude oil or vacuum distillation fraction or heavy oil such as residue oil, especially Is suitably used as a catalyst for hydrodesulfurization.

[0019]

Example Preparation of catalyst (Catalyst A) 20 g of citric acid monohydrate was dissolved in 100 cc of water, and 34.5 ammonium ammonium molybdate was added to this solution.
After adding 9 g (equivalent to 10% by weight as Mo amount of the obtained catalyst) by heating and dissolving, 5.24 g of phosphoric acid (0.75% by weight as P amount of the obtained catalyst) after cooling to room temperature
(Corresponding amount) was added and dissolved at room temperature. Finally, 10.44 g of cobalt carbonate (corresponding to 2.75 wt% as Co amount of the obtained catalyst) was added and heated to dissolve. Finally, water was added and the volume was adjusted to 180 ml. The supporting solution thus obtained was divided in half, diluted to 110 cc, impregnated with 150 g of an alumina carrier and dried overnight at 130 ° C., and then the remaining supporting solution was diluted to 95 cc and again The catalyst was impregnated, dried at the same temperature overnight, and calcined at 500 ° C. for 30 minutes to prepare a catalyst.

(Catalyst B) A catalyst was prepared in exactly the same manner as in the preparation of the above catalyst A, except that cobalt acetate was used in place of cobalt carbonate in an equimolar amount.

(Catalyst C) A catalyst was prepared in exactly the same manner as in the preparation of the above catalyst A, except that cobalt formate was used in place of cobalt carbonate in an equimolar amount as Co amount.

(Catalyst D) A catalyst was prepared by the same method except that cobalt nitrate was used instead of cobalt carbonate in an equimolar amount in the preparation of catalyst A.

(Catalyst E) Ammonium molybdate 3
After heating 4.59 g in water to dissolve it, cool to room temperature,
Ammonia water (15.2 ml) was added, and this solution was impregnated into 150 g of an alumina carrier and then dried overnight at 130 ° C., and then 5.24 g of phosphoric acid and 25.53 g of cobalt nitrate (the amount of Co of the obtained catalyst was 2 0.75% by weight) and re-impregnate with 95cc of the supported carrier solution.
A catalyst was prepared by drying overnight at 0 ° C and calcining at 500 ° C for 30 minutes. This is a method of loading twice using two solutions, the operation is complicated, and it took time to prepare the catalyst.

Activity test and crack evaluation For the catalyst obtained by the above-mentioned preparation method, Arabian light atmospheric distillation residue oil [specific gravity (15 ° C / 4 ° C): 0.9611, sulfur content: 3.33% by weight, nitrogen Min: 0.19% by weight] as a feed oil, hydrogen pressure: 120 kg / cm ² , reaction temperature: 36
0 and 380 ° C., LHSV: 1.0 hr ⁻¹ , H ₂ / Oil ratio:
The reaction was carried out under the oil passing condition of 1000 cc / cc, and the sulfur content and nitrogen content of the produced oil were measured. From these results and of the catalyst pellets obtained after calcination, the amount of vertical cracking in the catalyst obtained by causing vertical cracking was shown as the amount of vertical cracking, and is shown in Table 1.

[0025]

[Table 1]

From the above results, it can be seen that the amount of vertical cracks is extremely increased and the catalyst yield is decreased when the supporting liquid containing nitrate ions is used. Further, it can be seen that the desulfurization activity and denitrification activity are maintained even if the Group VIII iron group metal salt is other than nitrate.

[0027]

The method of the present invention has the effect of preventing vertical cracking of the catalyst and significantly improving the catalyst yield while maintaining the desulfurization and denitrification activities equivalent to those of the catalyst prepared by the conventional method.

Claims (2)

[Claims] 1. At least one ammonium salt selected from Group VIB metal elements of the periodic table, a phosphorus component, at least one salt selected from Group VIII iron group metal elements of the periodic table, and the above-mentioned period. Alumina carrier was impregnated with a solution containing at least 0.8 mol of citric acid per mol of Group VIB metal element in the table and containing no more than 1 part by weight of nitrate ion per 100 parts by weight of alumina carrier, and dried. A method for producing a hydrotreating catalyst, which comprises calcination. 2. The method for producing a hydrotreating catalyst according to claim 1, wherein the Group VIB metal element of the periodic table in the final catalyst composition of the hydrotreating catalyst is 5 to 15% by weight,
1 to 5% by weight of Group VIII iron group metal and 0.7 to 3 of phosphorus
A method for producing a hydrotreating catalyst, characterized in that the content thereof is in% by weight.