KR20110062968A - Preparation of cobalt and/or nickel-molybdenum sulfide sulfide catalyst supported on alumina for deep hydrodesulfurization - Google Patents

Abstract

PURPOSE: A manufacturing method of the alumina immersion cobalt for deep desulfurizaion and/or nickel-molybdenum sulfide catalyst is provided to manufacture the alumina immersion molybdenum sulfide catalyst for deep desulfurization which has excellent desulfurization performance by immersing after dispersing cobalt and/or nickel-molybdenum sulfide on the alumina carrier. CONSTITUTION: The manufacturing method of the alumina immersion cobalt for deep desulfurizaion and/or nickel-molybdenum sulfide catalyst includes the steps of: dissolving the sulfur in the organic solvent; putting molybdenum hexacarbonyl and gamma alumina into the sulfur - organic solvent solution; immersing the molybdenum sulfide in the alumina by adding ultrasonic wave; impregnating by melting cobalt and/or the nickel precursor in the solvent in the alumina in which the molybdenum sulfide is immersed; manufacturing the cobalt and/or the nickel - molybdenum sulfide catalyst by heat -treating under the temperature of 400°C; reacting the alumina in which the cobalt and/or the nickel molybdenum sulfide is immersed with the sulfurization agent in the hydrogen of the high pressure; sulfurizing the cobalt and/or the nickel.

Description

Preparation of cobalt and / or nickel-molybdenum sulfide sulfide catalyst supported on alumina for deep hydrodesulfurization

The present invention relates to a method for producing an alumina-supported molybdenum sulfide catalyst for deep desulfurization, and more particularly, to a high dispersion of the molybdenum sulfide as a main catalyst to alumina by using ultrasonic waves, and cobalt and / or nickel precursor as a promoter The present invention relates to a method for producing an alumina-supported cobalt and / or nickel-molybdenum sulfide catalyst for deep desulfurization having an excellent activity by supporting a molybdenum sulfide.

In order to lower the sulfur content in the conventional desulfurization process, it is necessary to operate in harsh operating conditions of high temperature and high pressure, thereby increasing operating costs and shortening the life of the catalyst.

US Patent Nos. 3,509,044 and 3,674,680 disclose a method for preparing molybdenum and cobalt precursors by impregnating gamma alumina in an aqueous solution of molybdenum and cobalt precursors, followed by drying, calcining and sulfiding. It is.

US Pat. Nos. 4,568,449 and 5,514,274 describe examples of enhancing the activity by adding phosphoric acid, an acidic substance, to improve the performance of a desulfurization catalyst. However, since the sintering phenomenon of cobalt and molybdenum occurs during the high temperature heat treatment process, there is a limit that the degree of activity increase is insignificant due to the decrease in metal dispersion.

US Pat. Nos. 4,243,554 and 6,156,693 disclose examples of using ammonium tetrathiomolybdate as a precursor to increase the surface area of the metal active phase present in the desulfurization catalyst. However, according to this method, since ammonium tetrathiomolybdate is decomposed at a low temperature, a catalyst can be prepared at a low temperature. However, the catalyst prepared by the above method is an alumina supported catalyst. It is difficult to use in the existing desulfurization process.

Korean Patent Laid-Open Publication No. 2003-0047416 discloses a method for preparing a catalyst for supporting molybdenum sulfide particles on alumina carrier with high dispersion by using ultrasonic waves. The catalyst prepared by this method includes cobalt and / or nickel as a promoter. There is a problem in that the activity is lower than the conventional cobalt and / or nickel- molybdenum sulfide catalyst because it is not.

Korean Laid-Open Patent Publication No. 2006-0020151 discloses a method of preparing a highly active catalyst by chemically depositing a cobalt precursor after supporting molybdenum sulfide particles on an alumina carrier by using ultrasonic waves, and cobalt is chemically deposited. The cobalt precursor loss is very large at. In addition, since the precursor is vaporized and supported in a gaseous state, there is a problem in that the catalyst preparation method is difficult to apply to an actual commercial catalyst manufacturing process.

In order to overcome the above problems, the present invention provides cobalt and / or nickel-molybdenum for deep desulfurization having high activity by carrying out high dispersion of cobalt and / or nickel-molybdenum sulfide, which is an active phase of a catalyst for depth desulfurization, on an alumina carrier. It is intended to provide a method for preparing a sulfide catalyst.

In order to achieve the above object, one aspect of the present invention is (A) dissolving sulfur in an organic solvent, molybdenum hexacarbonyl and gamma alumina are added to a sulfur-organic solvent solution, and then ultrasonically added to molybdenum sulfide in alumina (B) impregnating cobalt and / or nickel precursors as cocatalysts in alumina loaded with molybdenum sulfide prepared in step (A) in a solvent and heat-treating at a temperature below 400 ° C. to cobalt and / or nickel. Preparing a molybdenum sulfide catalyst; And (C) sulphurizing cobalt and / or nickel by reacting alumina loaded with cobalt and / or nickel molybdenum sulfide prepared in step (B) with a sulfiding agent in hydrogen at high pressure. Provided is a method for producing an alumina supported molybdenum sulfide catalyst.

The inventor of the present invention uses a method of introducing cobalt and / or nickel precursors by impregnation, and uses cobalt and / or nickel acetylacetonate precursors which are much cheaper than cobalt tricarbonylnitrosyl, which is a cobalt precursor used in chemical vapor deposition. In addition, the process was also supported by the impregnation method for easy commercial use to develop a method for producing a catalyst having excellent desulfurization performance without loss of cobalt precursor.

Hereinafter, each step will be described in more detail.

Step (A) is largely divided into a process of dissolving sulfur in an organic solvent and a process of supporting a molybdenum precursor in gamma alumina in a sulfur-organic solvent solution.

The process of dissolving sulfur in the organic solvent can be effectively performed by applying ultrasonic waves while flowing argon to the reactor. Preferably 20-40 kHz, 50-100 W / cm ² ultrasonic waves are added.

In the organic solvent used, hexadecane, 1,2,3,5-tetramethylbenzene, 1,3,5-trimethylbenzene, or a mixture thereof is preferably used as a solvent for dissolving molybdenum precursor and sulfur. no.

In the process of supporting the molybdenum precursor in gamma alumina, it is effective to use ultrasonic waves as in the case of dissolving the gamma alumina and molybdenum precursor in a sulfur-organic solvent solution in accordance with a desired loading amount and dissolving sulfur in an organic solvent. Most preferably, ultrasonic waves of 20-40 kHz and 50-100 W / cm ² are applied for a predetermined time while argon is flowed into the reactor.

Finally, the alumina loaded with molybdenum sulfide is filtered and washed with a vacuum apparatus, followed by vacuum drying at 150-250 ° C. to remove impurities remaining in the catalyst. At this time, it is preferable to use hexane or pentane as the organic solvent for washing, but is not limited thereto.

As a result of the step (A), an alumina in which molybdenum sulfide is supported with high dispersion is obtained as compared with a catalyst prepared by a conventional impregnation method in which molybdenum is impregnated with alumina.

Step (B) includes a step of impregnating and heat-treating a cobalt and / or nickel precursor which is a promoter in alumina on which molybdenum sulfide prepared in step (A) is supported in a solvent. Cobalt and / or nickel precursors may be cobalt and / or nickel acetate, cobalt and / or nickel halides, cobalt and / or nickel hydroxide, cobalt and / or nickel nitrate, cobalt and / or nickel sulfate, cobalt and / or Nickel napcenate, cobalt and / or nickelacetylacetonate or mixtures thereof may be used, preferably cobalt and / or nickelacetylacetonate. Cobalt and / or nickel precursors are dissolved in a solvent to meet the desired loading, impregnated, and heat treated at a temperature below 400 ° C., preferably at a temperature below 350 ° C.

The solvent used should be capable of dissolving the cobalt and / or nickel precursors, including H 2 O, alcohols (including Diol, Polyol), dimethyl sulfoxide (DMSO), dimethylformamide (DMF), dimethylacetamide (DMAC), and digime (Diglyme), dioxane, tetrahydrofuran (THF) or mixtures thereof are preferred, but not limited thereto.

Step (C) is a step of converting cobalt and / or nickel and molybdenum supported on alumina to a final sulfide state, in which alumina loaded with cobalt and / or nickel-molybdenum is added together with a sulfiding agent and a solvent, preferably The reaction is carried out for 2-6 hours at a temperature of 200-400 ℃, hydrogen pressure of 20-60bar.

It is preferable to use dodecane, pentadecane, hexadecane or a mixture thereof as the solvent, but is not limited thereto. As the sulfiding agent, dimethyl disulfide, dimethyl sulfide, butane thiol or mixtures thereof may be used, but not limited thereto.

The molybdenum content in the catalyst is preferably such that 3-50% by weight, cobalt and / or nickel content is 1-20% by weight.

The catalyst prepared through the above process is a catalyst prepared according to the prior art because molybdenum sulfide as a main catalyst is supported on a carrier with high dispersion and cobalt and / or nickel are selectively supported on the surface of molybdenum sulfide. It shows more excellent desulfurization performance.

According to the present invention, molybdenum sulfide as a main catalyst is supported on alumina carrier with high dispersion, impregnated with cobalt and / or nickel acetylacetonate as a cocatalyst, and then applied to an optimal heat treatment condition for depth desulfurization. An alumina supported molybdenum sulfide catalyst can be prepared.

The construction of the present invention will be further clarified by the following examples, the effect of which will be demonstrated in comparison with the comparative example.

≪ Example 1 >

A. Preparation of Alumina Supported Molybdenum Sulfide Catalyst

0.13 g of sulfur, 65 cc of hexadecane, 1 cc of 1,3,5-trimethylbenzene were placed in a 100 cc reactor, and the sulfur was dissolved by applying 20 kHz, 80 W / cm ² ultrasonic wave for 20 minutes while maintaining the reactor temperature at 60 ° C. Completely dissolved.

Subsequently, 0.53 g of molybdenum hexacarbonyl and 1.0 g of gamma alumina were added to the reactor as a molybdenum precursor, and ultrasonic waves at 20 kHz and 80 W / cm ² were introduced for 1 hour and 30 minutes while argon was introduced into the reactor at a flow rate of 25 cc / min at 60 ° C. After adding molybdenum sulfide to the alumina, the resultant was washed with excess hexane to remove the organic solvent, followed by vacuum drying at 200 ° C. for 2 hours to remove residual impurities.

B. Nickel Support

0.0922 g of nickel acetylacetonate as a nickel precursor was dissolved in 1.2 g of DMSO, and then impregnated in 0.4 g of alumina loaded with molybdenum sulfide prepared in step (A), followed by heat treatment in an air atmosphere at 230 ° C. to remove DMSO. The dried catalyst is sulfided in the same way as in step (C). The nickel content of the prepared nickel-molybdenum sulfide catalyst was 5% by weight, and the molybdenum content was 10% by weight.

C. Sulfurization of the Catalyst

0.3 g of molybdenum sulfide and nickel prepared in step (B), 10 cc of pentadecane (solvent), and 2 cc of dimethyl disulfide were added to the reactor with a sulfiding agent, and stirred at 1,000 rpm while maintaining the temperature at 300 ° C. under a hydrogen pressure of 40 bar. After reacting for 4 hours while sulfiding the catalyst, washed with hexane, and dried under vacuum at room temperature.

Comparative Example 1

A catalyst was prepared in the same manner as in Example 1, except that the catalyst prepared in Step (B) of Example 1 was heat-treated at 400 ° C. in an air atmosphere. The nickel content of the prepared nickel-molybdenum sulfide catalyst was 5% by weight, and the molybdenum content was 10% by weight.

Comparative Example 2

A catalyst was prepared in the same manner as in Example 1 except that 0.1304 g of nickel nitrate was dissolved in 1.2 g of H 2 O as a nickel precursor, and then impregnated with 0.5 g of alumina loaded with molybdenum sulfide prepared in step (A). The nickel content of the prepared nickel-molybdenum sulfide catalyst was 5% by weight, and the molybdenum content was 10% by weight.

Comparative Example 3

0.1304 g of nickel nitrate was dissolved in 1.2 g of H2O as a nickel precursor, and impregnated in 0.5 g of alumina loaded with molybdenum sulfide prepared in step (A), and then heat-treated at 400 ° C. in an air atmosphere. The catalyst was prepared by the method. The nickel content of the prepared nickel-molybdenum sulfide catalyst was 5% by weight, and the molybdenum content was 10% by weight.

Experimental Example 1

The catalysts prepared in Example 1 and Comparative Examples 1, 2, and 3 were subjected to the catalytic sulfidation process of Example 1, and then the dibenzothiophene desulfurization reaction was carried out by the following method. Described.

1. Reaction experiment

0.03 g of dibenzothiophene was dissolved in 30 cc of pentadecane and placed in a high pressure reactor together with 0.09 g of a catalyst, and desulfurization was performed for 30 minutes by introducing 40 bar of hydrogen at 320 ° C.

Table 1

The activity of the catalyst impregnated with nickel acetylacetonate as the cocatalyst nickel precursor was superior to the catalyst impregnated with nickel nitrate. In addition, the activity of the catalyst calcined at 400 ° C. after supporting nickel was inferior.

That is, it can be seen that the catalyst acts as an important factor that affects the catalyst activity, as well as the cocatalyst precursor and the heat treatment conditions after impregnation.

<Example 2>

A catalyst was prepared in the same manner as in Example 1, except that 0.056 g of cobalt acetylacetonate was dissolved in 0.35 g of DMSO as a cobalt precursor, and then impregnated in 0.35 g of alumina loaded with molybdenum sulfide prepared in step (A). The catalyst was sulfided by the method (C) in Example 1. The cobalt content of the prepared cobalt-molybdenum sulfide catalyst was 3% by weight, and the molybdenum content was 10% by weight.

<Comparative Example 4>

A catalyst was prepared in the same manner as in Example 1, except that 0.054 g of cobalt nitrate was dissolved in 0.35 g of H 2 O as a cobalt precursor, and then impregnated with 0.35 g of alumina loaded with molybdenum sulfide prepared in step (A). The catalyst was sulfided by the method (1). The cobalt content of the prepared cobalt-molybdenum sulfide catalyst was 3% by weight, and the molybdenum content was 10% by weight.

Comparative Example 5

In 6 g of alumina, 2.15 g of ammonium heptamolybdate as a molybdenum precursor was dissolved in 1.5 g of H ₂ O, impregnated in 6 g of alumina, dried at 150 ° C. for 2 hours, and calcined at 500 ° C. for 2 hours to carry molybdenum-supported alumina. Was prepared. In addition, in order to support cobalt, 0.75 g of cobalt nitrate was dissolved in 2.1 g of H ₂ O, impregnated in alumina loaded with molybdenum, dried at 150 ° C. for 2 hours, and calcined at 500 ° C. for 2 hours to obtain cobalt-molybdenum oxide. A supported alumina catalyst was prepared.

0.3 g of alumina loaded with cobalt-molybdenum oxide prepared by the above method, 10 cc of pentadecane (solvent), and 2 cc of dimethyl disulfide were added to a reactor with a sulfiding agent, and stirred at 1,000 rpm while maintaining the temperature at 350 ° C. under a hydrogen pressure of 40 bar for 4 hours. The reaction was followed by sulfidation of the catalyst, washing with hexane, and vacuum drying at room temperature.

The cobalt content of the prepared cobalt-molybdenum sulfide catalyst was 3% by weight, and the molybdenum content was 10% by weight.

Comparative Example 6

Catalysts were prepared for comparison with conventional techniques for chemical vapor deposition of cobalttricarbonylnitrosyl. 3 cc of cobalt tricarbonylnitrosyl as a cobalt precursor and 0.3 g of alumina loaded with molybdenum sulfide prepared in step (A) were put into a vaporization reactor, and nitrogen was introduced at a flow rate of 24 cc / min for 5 minutes at room temperature to carry molybdenum sulfide. The precursor was deposited on the alumina.

Subsequently, nitrogen was passed through a flow rate of 30 cc / min for 30 minutes to remove the physically adsorbed cobalt precursor, and nitrogen was flowed for 1 hour at a flow rate of 20 cc / min, followed by heat treatment at 200 ° C. to form carbonyl groups and nitro groups present in the cobalt precursor. Ligands, such as a practical group, were removed. This chemical vapor deposition was repeated five times to prepare a cobalt-molybdenum sulfide catalyst having a cobalt content of 3.5% by weight and a molybdenum content of 10% by weight, and the catalyst was sulfided by the method (C) of Example 1.

Experimental Example 2

The dibenzothiophene desulfurization reaction of the catalysts prepared in Example 2 and Comparative Examples 4, 5 and 6 was carried out by the method of Example 1, and the results are shown in Table 2 after the reaction for 40 minutes.

TABLE 2

The desulfurization activity of the cobaltacetylacetonate catalyst of Example 2 prepared according to the present invention was the best.

Claims (5)

(A) dissolving sulfur in an organic solvent, adding molybdenum hexacarbonyl and gamma alumina to a sulfur-organic solvent solution, and then applying ultrasonic waves to support molybdenum sulfide in alumina. (B) a cobalt and / or nickel precursor, which is a cocatalyst, is impregnated in a solvent in an alumina loaded with molybdenum sulfide prepared in step (A), and heat-treated at a temperature below 400 ° C. to form a cobalt and / or nickel-molybdenum sulfide catalyst. Manufacturing; And (C) Desulfurization alumina comprising the step of reacting cobalt and / or nickel molybdenum sulfide-supported alumina prepared in step (B) with a sulfiding agent to sulfide cobalt and / or nickel in hydrogen at high pressure. Process for preparing supported molybdenum sulfide catalyst. The method of claim 1, Cobalt and / or nickel precursor is cobalt and / or nickel acetylacetonate method for producing alumina-supported molybdenum sulfide catalyst for depth desulfurization. The method of claim 1, A method for producing an alumina-supported molybdenum sulfide catalyst for depth desulfurization, characterized in that the molybdenum content in the catalyst is 3 to 50% by weight, and the content of cobalt and / or nickel is 10 to 20% by weight. The method of claim 1, The heat treatment in the step (B) is a method for producing alumina-supported molybdenum sulfide catalyst for depth desulfurization characterized in that the heat treatment at 350 ℃ or less. The method of claim 1, In step (B), the solvent is H 2 O, alcohol (including Diol, Polyol), dimethyl sulfoxide (DMSO), dimethylformamide (DMF), dimethylacetamide (DMAC), diglyme, dioxane, tetrahydro A method for producing an alumina-supported molybdenum sulfide catalyst for depth desulfurization using furan (THF) or a mixture thereof.