KR20180073392A - Hydrodesulfurization catalyst and method for preparing the same - Google Patents

Abstract

The present invention relates to a catalyst for sulfur conversion and a production method thereof. More specifically, the production method of a catalyst for sulfur conversion comprises the following steps: mixing boehmite powder, cobalt salt, and nickel salt to prepare mixed slurry; adding ammonia water to obtain a reactant; mixing the reactant with TiO_2 powder to prepare pellets; and heat-treating the pellets. The catalyst for sulfur conversion produced by the method has excellent chemical resistance and sulfur element discharging ability.

Description

TECHNICAL FIELD [0001] The present invention relates to a catalyst for sulfur conversion and a method for producing the same,

More particularly, the present invention relates to a method for producing a catalyst for high-efficiency sulfur conversion using boehmite powder and TiO ₂ powder for preparing a catalyst for sulfur conversion, .

In general, gamma alumina is widely used as a material for a catalyst for sulfur conversion, and an active auxiliary agent is added thereto in order to increase the catalyst efficiency. The impregnation method is widely used as an active additive method. In the impregnation method, a water-soluble salt containing an active ion is dissolved in water to prepare an aqueous solution, gamma alumina is impregnated, active ions are added, to be.

For example, in the Nippon Steel Corporation patent No. KR2010-008723 A precipitation agent is added to a solution of a nickel compound and a magnesium compound to coagulate nickel and magnesium to form a precipitate, and the precipitate is dried and calcined to produce an oxide of nickel and magnesium, and the alumina powder (a) Water or (b) an alumina sol is further added and mixed to produce a mixture, and at least the mixture is dried and calcined to prepare a catalyst. In another Japanese Patent Application Laid-Open No. 7-31878, a catalyst having a hydrogenation activity is supported on a catalyst support containing alumina, magnesia and silica to produce a catalyst.

Thus, the gamma-alumina component used in the conventional catalyst carrier has an incomplete crystal structure, and oxygen ions are diffused in the spinel structure having such an incomplete crystal structure, resulting in rearrangement of the atoms, so that the specific surface area is drastically reduced, The sulfur element is adsorbed between the gamma alumina lattices and the activity is lowered.

Such a disadvantage leads to a problem that the yield of the reaction product during the catalytic reaction is reduced and the process stability is poor. Particularly, at a high temperature of 400 ° C or higher in the desulfurization treatment process, elemental sulfur production is remarkably delayed, and the desulfurization yield tends to decrease. Generally, the desulfurization operation is taking place at around 300 ° C.

Therefore, it is expected that the present invention can be widely applied in the related art, if the above-mentioned problems are not caused by using the gamma alumina component and the catalyst for sulfur conversion which is stable at high temperature and high efficiency is provided.

One aspect of the present invention is to provide a method for producing a catalyst for sulfur conversion.

Another aspect of the present invention is to provide a catalyst for sulfur conversion using boehmite.

According to one aspect of the present invention, there is provided a method for producing a mixed slurry, comprising: mixing a boehmite powder, a cobalt salt, and a nickel salt to prepare a mixed slurry; Adding ammonia water to obtain a reactant; Mixing the reactant with TiO ₂ powder to prepare a pellet; And heat-treating the pellets.

The step of preparing the mixed slurry is preferably performed by mixing 2-4 mol% of cobalt salt and 5-10 mol% of nickel salt based on metal ion.

The step of adding the ammonia water to obtain a reactant is preferably carried out by adjusting the pH to 9.5 to 10 and reacting in a reflux reactor.

The temperature of the reflux reactor is preferably maintained at 80 to 90 캜.

Preferably, the step of preparing the pellet is performed by mixing 5 to 10% by weight of TiO ₂ powder.

The step of heat-treating the pellet is preferably performed at a temperature of 500 to 600 ° C.

According to another aspect of the present invention, there is provided a catalyst for sulfur conversion produced by the above-described process for producing a catalyst for sulfur conversion of the present invention.

According to another aspect of the present invention, there is provided a catalyst for sulfur conversion comprising boehmite, TiO ₂ , cobalt and nickel.

The cobalt and nickel preferably contain 2 to 4 mol% of cobalt and 5 to 10 mol% of nickel based on the metal ion.

The TiO ₂ is preferably contained in an amount of 5 to 10 wt% or less based on the weight of the total catalyst.

The catalyst for the conversion of high-efficiency sulfur produced according to the present invention is excellent in chemical resistance and sulfur element discharge ability and exhibits excellent catalytic effect even under high temperature process conditions of 300 or more. In addition, it can be used for a high temperature steam reforming reaction or an exhaust gas treatment , Desulfurization and denitrification. Furthermore, since the catalyst for sulfur conversion of the present invention is environmentally friendly and has excellent physical and chemical properties, high efficiency and stability are ensured, so that the lifetime of the catalyst is prolonged, and the cost saving effect of catalyst replacement can be obtained.

1 is a graph showing the percentage of sulfur conversion according to nickel ion content.
2 is a graph showing the percentage of sulfur conversion depending on the amount of TiO ₂ added.
3 is a graph showing the percentage of sulfur conversion according to the catalyst heat treatment temperature.

Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below.

According to the present invention, there is provided a method for producing a catalyst for high-efficiency sulfur conversion using boehmite powder and TiO ₂ powder, and a catalyst therefor.

More specifically, the method for preparing a catalyst for sulfur conversion of the present invention comprises: preparing a mixed slurry by mixing a boehmite powder, a cobalt salt, and a nickel salt; Adding ammonia water to obtain a reactant; Mixing the reactant with TiO ₂ powder to prepare a pellet; And heat treating the pellet.

The present invention relates to a method of adding boehmite powder having a large specific surface area and excellent surface activity to a boehmite by electrodeposition reaction, Lt; / RTI >

The preparation of the mixed slurry is preferably performed by mixing 2 to 4 mol% of cobalt salt and 5 to 10 mol% of nickel salt based on the metal ion, more preferably about 3 mol% of cobalt salt based on metal ion, And 6 to 9 mol% of a nickel salt.

When the nickel ion is contained in an amount exceeding 10 mol% as the active auxiliary agent, there is no increase in catalytic effect with respect to the amount of nickel ion increase, which is not preferable for the process economy. On the other hand, .

Further, when the cobalt ion is contained in an amount exceeding 4 mol% as the active auxiliary, the performance of the catalyst is not improved in spite of the increase in the content, so that the use of a large amount of expensive cobalt is not preferable in view of the process economy, %, There is a problem that the performance of the catalyst is deteriorated.

The boehmite powder is mixed with a cobalt salt and a nickel salt on the basis of metal ions as an active auxiliary, and the electrodeposition reaction proceeds in order to improve the surface adsorption of the adhesion and the preparation using the mixed aqueous solution slurry. To this end, ammonia water is added to the mixed slurry to obtain a reactant.

The step of adding the ammonia water to obtain a reaction product is preferably carried out by adjusting the pH to 9.5 to 10 and reacting in a reflux reactor. When the pH is less than 9.5, the activity of the cobalt ion and the nickel ion may not be uniform, There is a problem that the electrodeposition efficiency is lowered, and even when the pH exceeds 10, the electrodeposition reaction efficiency is lowered.

At this time, the temperature of the reflux reactor is preferably maintained at 80 to 90 ° C. When the reaction temperature at which the electrodeposition reaction is performed is less than 80 ° C, the reaction rate is slowed to take more than 2 hours, The amount of reflux increases due to the generation of water vapor, which is undesirable because it affects the reaction of the solution.

Subsequently, the step of mixing the TiO ₂ powder with the reactant to produce pellets is preferably performed by mixing 5 to 10% by weight of TiO ₂ powder, more preferably 7 to 10% by weight will be. When the TiO ₂ powder is contained in an amount of less than or equal to 5 to 10 weight percent, the sulfur conversion tends to decrease.

On the other hand, the step of heat-treating the pellets is preferably carried out at a temperature of 500 to 600 ° C, more preferably 500 to 550 ° C. When the heat treatment is carried out at a temperature lower than 500 ° C., the boehmite crystal structure tends to be partially unstable, and the efficiency is lowered when the elemental sulfur is converted due to the presence of the ammonium salt complex. On the other hand, when the heat treatment is performed at a temperature higher than 600 ° C, the boehmite is deformed into a gamma-alumina phase structure, and the specific surface area is reduced to cause a problem of exhaust after the elemental sulfur conversion. .

Therefore, when the heat treatment is performed at a temperature range of 500-600 ° C, which is the heat treatment temperature range of the catalyst for sulfur conversion of the present invention, an excellent elemental sulfur conversion catalyst capable of exhibiting the maximum sulfur conversion catalyst effect due to the inclusion of a uniform and well- Can be obtained.

According to another aspect of the present invention, there is provided a catalyst for sulfur conversion produced by the above-described method for producing a catalyst for sulfur conversion of the present invention as described above.

The catalyst for sulfur conversion of the present invention comprises boehmite, TiO ₂ , cobalt and nickel, and all the composition-related matters mentioned in the above-mentioned method for producing a catalyst for sulfur conversion are applied equally.

The cobalt and nickel preferably contain 2 to 4 mol% of cobalt and 5 to 10 mol% of nickel based on the metal ion.

On the other hand, the TiO ₂ is preferably contained in an amount of 5 to 10 wt% or less based on the weight of the total catalyst.

The high-efficiency sulfur purging catalyst produced according to the present invention is excellent in chemical resistance and sulfur element discharging ability, exhibits excellent catalytic effect even under process conditions at a high temperature of 300 ° C or higher, and exhibits a high temperature steam reforming reaction and an exhaust gas treatment , Desulfurization and denitrification. Furthermore, since the catalyst for sulfur conversion of the present invention is environmentally friendly and has excellent physical and chemical properties, high efficiency and stability are ensured, so that the lifetime of the catalyst is prolonged, and the cost saving effect of catalyst replacement can be obtained.

Hereinafter, the present invention will be described more specifically by way of specific examples. The following examples are provided to aid understanding of the present invention, and the scope of the present invention is not limited thereto.

Example

1. Preparation of catalyst for sulfur conversion

(1) Confirmation of influence of pH change

The boehmite powder was mixed with 3 mol% of cobalt salt and 5 mol% of nickel salt as an active agent on the basis of metal ions. Ammonia water was added in the electrodeposition reactor to adjust the pH from 9 to 0.5 at intervals of 10.5. The cobalt and nickel were electrodeposited on the surface of the boehmite by reacting for 2 hours or longer, followed by filtering and drying to prepare a powder and measure the electrodeposition amount. At this time, the electrodeposition reaction temperature was maintained at 80 캜.

At this time, the electrodeposition amount was analyzed in ICP (inductively coupled plasma) by dissolving in acid, and the amount of cobalt and nickel ion in the resultant was converted into mol%, and the results are shown in Table 1 below.

Electroplating Reaction Basicity Conditions (pH) Electrodeposition amount (mol%) Electrodeposition yield (%) cobalt nickel cobalt nickel 9.0 2.51 4.17 83.7 83.4 9.5 2.90 4.85 96.7 97.0 10.0 2.94 4.92 97.6 98.4 10.5 2.83 4.60 94.3 92.0

In Table 1, the surface deposition amounts of cobalt and nickel ions were different by electrodeposition reaction when the pH condition was constant under the condition of electrodeposition reaction. As a result, there was a difference in electrodeposition amount. In addition, although it was prepared by adding 3 mol% and 5 mol% of cobalt and nickel ions respectively, it was found that a smaller amount was deposited in actual yield.

At pH 9.0, the amount of electrodeposition was 83.7%, which was less than 95% of the actual amount of 3 mol%, and 94.3% of electrodeposition was observed at pH 10.5. The preferable pH condition was 9.5 to 10.0.

(2) Confirm the effect of temperature change

The electrodeposition reaction was carried out in the same manner as in the above (1) while changing the electrodeposition reaction temperature from 70 ° C to 90 ° C at intervals of 10 ° C while maintaining the pH of 10.0. The time for the termination of the electrodeposition reaction according to each temperature was confirmed by measuring the redox potential (ORP), and the redox potential was abruptly decreased at the termination of the reaction. Based on these results, the reaction termination time was determined Table 2 shows the reaction termination time.

Electrodeposition reaction temperature (캜) Reaction termination time (minutes) 70 120 80 38 90 32

As can be seen from Table 2, the reaction termination time decreases rapidly as the electrodeposition reaction temperature increases. The faster the deposition reaction rate, the faster the reaction termination time is terminated and the efficiency of the production process is improved . In particular, it was confirmed that the reaction was terminated within 40 minutes at a temperature of 80 ° C or higher, whereas it took 120 minutes at 70 ° C or lower.

(3) On the nickel ion content  Confirm the impact of

In order to electrodeposit cobalt ions and nickel ions onto the surface of the boehmite powder, cobalt ions were fixed at 3 mol% using a water-soluble salt, nickel ions were added at 4 mol% to 11 mol% , The reaction conditions were adjusted to pH 10 with ammonia water to adjust the reaction temperature to 80 ° C., followed by washing with water. Then, 5 wt% of TiO ₂ powder was mixed to prepare pellets, For 1 hour to prepare a catalyst for sulfur conversion.

In order to perform the sulfur conversion performance test for each of the prepared catalyst samples, 50 g of the prepared catalyst was loaded into a tube furnace, and H ₂ S gas and SO ₂ gas were added at a molar ratio of 2: 1, and the components of the exhaust gas were analyzed by gas chromatography And the sulfur conversion was calculated. The results are shown in Fig.

As shown in FIG. 1, the conversion of sulfur production was 95% or more at a nickel ion content of 5 mol% or more, but decreased at 10 mol% at 11 mol% As shown in Fig. As a result, it was confirmed that when the nickel ion content is maintained at 5 to 10 mol%, it is desirable to obtain a sulfur conversion rate of 95% or more.

(4) TiO ₂  Confirm the effect of powder addition amount

In order to electrodeposit cobalt ions and nickel ions onto the surface of the boehmite powder, cobalt ions were fixed at 3 mol% using a water-soluble salt, and nickel ions were fixed at 7 mol% , The reaction condition was adjusted to pH 9.5 using ammonia water, and the reaction temperature was adjusted to 80 ° C. After filtration and washing with water, TiO ₂ The pellets were prepared by mixing powders varying from 2 wt% to 11 wt%, and then heat-treated at 500 ° C for 1 hour to prepare a catalyst for sulfur conversion.

In order to test the sulfur conversion performance of each of the prepared samples, 50 g of the prepared catalyst was loaded in a tube furnace, and H ₂ S gas and SO ₂ gas were introduced at a molar ratio of 2: 1, and the components of the exhaust gas were analyzed by gas chromatography The sulfur conversion was calculated and the results are shown in FIG.

As shown in FIG. 2, the sulfur conversion rate increased up to 10 wt% as the TiO ₂ powder was added to the catalyst in the electrodeposition reaction at 3 mol% of cobalt ions and 7 mol% of nickel ions, but decreased at 11 wt% Respectively. This is because the conversion rate is different due to the correlation of cobalt and nickel ion acting as active additives.

(5) On the nickel ion content  Confirm the impact of

In order to set the conditions under which the specific surface area is maintained and the sulfur conversion performance is excellent, a sample containing 4 wt% of TiO ₂ is heated to 400 ° C at a temperature of 100 ° C at a temperature of 700 ° C. And H ₂ S gas and SO ₂ gas were introduced at a molar ratio of 2: 1. The composition of the exhaust gas was analyzed by gas chromatography to measure elemental sulfur conversion. The results are shown in FIG.

In the catalyst for sulfur conversion of the present invention, the crystal structure is changed according to the heat treatment temperature, and the surface activity is different. As shown in FIG. 3, the sulfur conversion rate is lowered at a temperature of 400 ° C. due to a chemical compound bonded to ammonium which is undifferentiated. At 700 ° C. or higher, boehmite shifts to gamma alumina, The surface area is lowered and the activity is lowered. As a result, it was confirmed that the range of 500 to 600 ° C. was the preferable heat treatment condition of the present invention.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be obvious to those of ordinary skill in the art.

Claims (10)

Mixing a boehmite powder, a cobalt salt and a nickel salt to prepare a mixed slurry;
Adding ammonia water to obtain a reactant;
Mixing the reactant with TiO ₂ powder to prepare a pellet; And
And heat treating the pellet
A method for producing a catalyst for sulfur conversion.
2. The method of claim 1, wherein the step of preparing the mixed slurry is carried out by mixing 2 to 4 mol% of cobalt salt and 5 to 10 mol% of nickel salt based on the metal ion.
The method of claim 1, wherein the step of adding ammonia water to obtain a reactant is carried out by adjusting the pH to 9.5 to 10 and reacting in a reflux reactor.
The method of claim 3, wherein the temperature of the reflux reactor is maintained at 80 to 90 占 폚.
2. The method of claim 1, wherein the step of preparing the pellets comprises adding 5 mol% of TiO ₂ powder, To 10% by weight, based on the total weight of the catalyst.
The method according to claim 1, wherein the heat treatment of the pellet is performed at a temperature of 500 to 600 ° C.
A catalyst for the conversion of sulfur produced by the process for producing a catalyst for sulfur conversion according to any one of claims 1 to 6.
Boehmite, TiO ₂ , cobalt and nickel.
9. The catalyst according to claim 8, wherein the cobalt and nickel comprise 2 to 4 mol% of cobalt and 5 to 10 mol% of nickel based on the metal ion.
The catalyst according to claim 8, wherein the TiO ₂ is contained in an amount of 5 wt% to 10 wt% or less based on the weight of the total catalyst.

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