KR20140106793A - Method for the preparation of molded article of nickel-containing catalyst for mixed modification reaction of methane and the molded catalyst article thus obtained - Google Patents

Abstract

According to the present invention, provided are a method for preparing a nickel-containing catalyst molded article for mixed modification reaction of methane and a catalyst prepared therefrom. The method includes the steps of: a) supporting a Ce precursor or a Ce-Zr precursor to a MgAlOx supporter, and supporting a Ni precursor simultaneously or sequentially; b) drying a mixture of the Ni precursor/Ce precursor or the Ce-Zr precursor/MgAlOx at 100-150°C and acquiring a catalyst precursor; c) materializing the dried catalyst precursor to have a density of 1.0-2.0 g/cc and acquiring a catalyst shape; and d) plasticizing the acquired catalyst shape at a temperature of 850-1250°C and acquiring the catalyst molded article.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a nickel-containing catalyst formed body for mixed reforming reaction of methane,

The present invention relates to a method for producing a nickel-containing catalyst molded body for mixed reforming reaction of methane, which can be used in a process for producing synthetic gas from methane contained in natural gas on a commercial scale, and to the obtained catalyst molded body.

As a method for producing synthesis gas (CO, H ₂ ) from methane (CH ₄ ), which is a main component of natural gas, steam reforming of methane (SRM) using methane partial oxidation of methane (POM), and carbon dioxide reforming of methane (CDR) using carbon dioxide.

The carbon monoxide and hydrogen (H ₂ / CO) ratios generated in each reforming reaction are 3, 2 and 1, respectively, and can be used differently depending on the ratio (H ₂ / CO) required in the subsequent process. For example, in the SRM reaction, which is a strong endothermic reaction, a H ₂ / CO ratio of 3 or more can be obtained, which is a reforming reaction suitable for hydrogen production and ammonia synthesis reaction. In the case of POM reaction, H ₂ / CO ratio is about 2 Methanol reforming reaction and the Fischer-Tropsch reaction. Next, the advantages and disadvantages of the reforming reaction and the calorific value are summarized.

(1) Steam reforming reaction of methane (SRM)

CH ₄ + H ₂ O = 3H ₂ + CO? H = 226 kJ / mol

-> high endothermic reaction, H ₂ / CO> 3, excess steam required

(2) Partial Oxidation of Methane (POM)

CH ₄ + 0.5 O ₂ = 2H ₂ + CO ΔH = - 44 kJ / mol

-> mild exothermic reaction, H ₂ / CO = 2, O ₂ production process is required

(3) Carbon Dioxide Reforming Reaction of Methane (CDR)

CH ₄ + CO ₂ = 2H ₂ + 2CO H = 261 kJ / mol

-> high endothermic reaction, H ₂ / CO = 1, CO ₂ addition required

The above-mentioned reforming reaction can produce a synthesis gas having different H ₂ / CO ratios depending on the catalyst and reactants to be used, and many patents using differentiation that the subsequent synthesis process using the synthesis gas are appropriately changed are currently applied 2006-0132293, Korean Patent Publication 2005-0051820, and Korean Patent Publication 10-2010-0014012.

In the case of SRM, which is currently in commercial use, a Ni / Al ₂ O ₃ catalyst system is mainly used in a range of steam to methane molar ratio of 4 to 6: 1 at a reaction temperature of 750 to 850 ° C. However, The catalyst system containing transition metal and alkali metal as a noble metal or cocatalyst has been extensively studied [Journal of Molecular Catalysis A 147 (1999) 41].

In the case of the CDR reaction, the deactivation of the catalyst due to the carbon deposition is more severe than the SRM reaction, and as a method for suppressing the deactivation of the catalyst, the catalyst of the precious metal catalyst (Pt / ZrO ₂ ), Ni / MgO or Ni / MgAlOx series, (Catalysis Today 46 (1998) 203, Catalysis communications 2 (2001) 49 and Korean Patent Laid-open No. 10-2007-0043201). In general, when the commercially available SRM catalyst is directly used for the CDR reaction and the mixed reforming process (CDR + SRM), there is a problem that the deactivation by carbon deposition is further accelerated.

According to the results of previous studies of the present inventors (Korean Patent Publication No. 2002-0021721, Korean Patent Publication No. 2004-0051953 and Korean Patent Publication No. 2002-0088213), a zirconia carrier modified with cerium as a catalyst system effective for SRM and CDR reaction And a method in which nickel is supported on an alumina support or catalysts prepared by coprecipitation of cerium, zirconium and nickel are used to inhibit catalyst deactivation by carbon deposition.

Korean Patent Application No. 10-2008-0075787 discloses a process for producing a syngas using a nickel-based reforming catalyst capable of simultaneously carrying out SRM and CDR as a mixed reforming process, and using methanol as a synthesis and Fischer-Tropsch reaction process Lt; / RTI > Generally, it is known that the composition ratio of a thermodynamically suitable synthesis gas (H ₂ / (2CO + 3CO ₂ )) in the synthesis of methanol is about 1.05, and as the ratio increases, the yield of methanol increases. There is a need to add additional hydrogen or adjust the conversion in the CDR reaction to adjust. The Fischer-Tropsch reaction using an iron-based catalyst is characterized in that excess hydrogen is generated during the reaction due to a high water gas conversion reaction (CO + H 2 O = H 2 + CO 2) and the selectivity to CO 2 is high. (H ₂ / CO = 0.5-0.7) containing CO2 and a low molar ratio due to the high water gas conversion reaction. The Fischer-Tropsch reaction is also advantageous.

Commercially available catalysts for mixed reforming reactions of methane are formed catalysts comprising a metal deposited on a support, which results in a reduction in the performance associated with aging and / or carbon deposition during the process, as well as the disruption of the catalyst due to mechanical expansion to carbon deposition Problems arise. Typically, when the decrease in catalytic activity becomes apparent, the reaction temperature is increased to compensate for the decrease in activity, at which point the catalyst is considered to be at the end of its lifetime and replacement will be necessary.

There is a great deal of effort to develop catalysts that have resistance to the performance of catalysts for mixed reforming reactions of methane over many years, such as their initial activity and selectivity, and performance degradation associated with aging and / or carbon deposition , With most solutions resulting in a change in composition and / or composition of the composition.

In the present invention, as disclosed in Korean Patent Application No. 10-2008-0075787, a catalyst prepared by pre-treating a MgAlOx metal oxide support with a single component or two components of cerium and zirconium using nickel as an active ingredient is dried, (SRM and CDR reforming reaction) on a commercial scale to obtain a catalyst molded body excellent in mechanical durability such that it can prevent the catalyst from being broken due to carbon deposition even though the deposition can be further suppressed by itself, So that it is possible to provide an optimum catalytic molding which can be operated.

The study of the present invention has been carried out with the support of the Korea Energy Technology Evaluation Institute (KETEP) according to the "Energy Resources Technology Development Project" (Task No. 2012T100201578) of the Ministry of Knowledge Economy of the Republic of Korea [This work was supported by the Korea Institute of Energy Technology Evaluation Planning (KETEP) under "Energy Efficiency & Resources Programs" (Project No. 2012T100201578) of the Ministry of Knowledge Economy, Republic of Korea.

1. Korean Patent Publication No. 2002-0021721 2. Korean Patent Publication No. 2004-0051953 3. Korean Patent Publication No. 2002-0088213 4. Korean Patent Application No. 10-2008-0075787

1. Journal of Molecular Catalysis A 147 (1999) 41

In the nickel-containing catalyst for the mixed reforming reaction of methane prepared by carrying and firing a Ce or Ce-Zr precursor and Ni precursor on a MgAlOx support, the catalyst is not formed into a powder form and is shaped or shaped for commercial use It is possible to reduce the carbon deposition and prevent the decomposition of the catalyst due to the carbon deposition, without damaging much of the physical properties and properties that can be achieved with the powdery catalyst, Thereby preparing a nickel-containing catalyst preform having excellent durability.

The present inventors have carefully controlled the temperature and density at each step in drying, shaping and calcining the catalyst precursor obtained by supporting the Ce or Ce-Zr precursor and the Ni precursor on the MgAlOx support, By studying the conditions that maximize the coke resistance by using a binder, it is possible to study properties such as compressive strength which can be used for commercial purposes and which can be advantageously applied to a commercial process, shapes such as cylinders and hollow cylinders, And thus the present invention has been completed.

According to the present invention there is provided a nickel-containing catalyst for the mixed reforming reaction of methane, which has properties such as compressive strength, properties such as cylinder and hollow cylinder, and coke resistance, which can be used commercially and can be advantageously applied to commercial processes A molded body could be produced.

FIG. 1 is a photograph of the single-hollow cylindrical catalyst prepared in Example 1 of the present invention,
2 is a photograph of the cylindrical catalyst prepared in Example 2 of the present invention,
3 shows TPR results of the catalysts 1-1 to 1-4 in Test Example 1 of the present invention.

A first object of the present invention is to provide a method for producing a nickel-containing catalyst molded body for mixed reforming reaction of methane, comprising the steps of:

a) a Ce precursor or a Ce-Zr precursor is supported on a MgAlOx support, and a Ni precursor is supported simultaneously or successively,

b) drying the resultant Ni precursor / Ce precursor or a mixture of Ce-Zr precursor / MgAlOx at 100-150 ° C to obtain a catalyst precursor,

c) shaping the dried catalyst precursor to have a density of 1.0 to 2.0 g / cc, preferably 1.2 to 1.8 g / cc, in particular 1.5 to 1.7 g / cc,

d) The obtained catalyst body is calcined at a temperature of 850 to 1250 캜, preferably 900 to 1200 캜, more preferably 950 to 1150 캜, particularly 1000 to 1150 캜, to produce 25 to 160 MPa, preferably 30 A catalyst having a specific surface area of from 4 to 150 m ² / g, preferably from 10 to 140 m ² / g, in particular from 20 to 130 m ² / g, with a compressive strength of from 1 to 150 MPa, in particular from 40 to 140 MPa, A molded article was obtained.

A second object of the present invention is to provide a catalyst for mixed reforming reaction using nickel as an active ingredient obtained by the above production method.

Hereinafter, the present invention will be described in more detail with reference to the drawings.

According to embodiments of the present invention, the Ce precursor may be used in an amount of 3 to 20 wt.%, Particularly 4 to 18 wt.%, Preferably 5 to 15 wt.%, Based on the total weight of the catalyst precursor, The Ni precursor may be used in an amount of 5 to 20 wt.%, Particularly 7 to 18 wt.%, Preferably 9 to 15 wt.%, Based on the total weight of the catalyst precursor.

According to another embodiment of the invention, the MgAlOx support described above is selected from the group consisting of sodium carbonate, potassium carbonate, ammonium carbonate or sodium bicarbonate in a metal mixture of an alumina precursor and a magnesium precursor selected from an acetate salt, a hydroxide or a nitrate. For example, a substance having the formula Mg _{2 x} Al ₂ (OH) _{4 x + 4} CO ₃ .nH ₂ O. The above-mentioned basic precipitation agent may be used alone or in combination of _two or more.

As the MgAlOx support, a commercially available aluminum magnesium hydroxycarbonate or those prepared therefrom can be used. The MgAlOx support is commercially available under the trade name PURAL (R) MG30 (manufactured by Sasol, Mg _2x Al ₂ (OH) _{4x + 4} CO ₃ .nH ₂ O, mass ratio MgO: Al ₂ O ₃ = 30: 70].

In one embodiment of the present invention, the Ce (or Ce-Zr) precursor or Ni precursor is added to water and allowed to stand for a sufficient time, specifically for 30 minutes or more, preferably for 40 minutes or more, It may be desirable to prepare a homogeneous solution by stirring. The Ce (or Ce-Ze) precursor solution and Ni precursor solution thus prepared may also be combined and stirred for a sufficient time as described above to prepare a homogeneous solution.

The Ce precursor, the Ce-Zr precursor and the Ni precursor can be supported on the support by any of the deposition methods commonly used in the art such as a spraying method, an impregnation method, a dipping method and the like.

The Ce precursor, the Zr precursor and the Ni precursor are precursors of each metal commonly used in the art, and specifically, halide, acetate, hydroxide and nitrate can be used, and they can be carried on a support sequentially or simultaneously . In the present specification, the Ce-Zr precursor may mean both a mixture of a Ce precursor and a Zr precursor, or a precursor compound containing both Ce and Zr.

The types and types of Ce precursors or Ce-Zr precursors (i.e., Ce precursor and Zr precursor) and Ni precursors, and methods and process conditions for supporting them on MgAlOx supports are described in Korean Patent Application No. 10-2008-0075787, The above patent application specification is incorporated herein by reference.

In an embodiment of the invention, the drying step of step b) is carried out at a temperature of from 100 to 150 ° C, preferably from 110 to 140 ° C, in particular from 110 to 130 ° C, with a water content of less than 30% by weight of the total catalyst precursor, Is less than 20% by weight, in particular less than 10% by weight. Water may act as a fluidizing agent in the powder, but suitable moisture can act as a binder in the shaping step. Therefore, when the moisture content is 30% by weight or more, it is highly likely that the wet powder can not be formed or that the shaped catalyst body is easily broken or collapsed. If the moisture content is less than 5%, it takes a long time to dry, and it is difficult to form the dry powder and use of the binder may become necessary.

Thermogravimetric analysis (TGA) of aluminum magnesium hydrocarbons [Mg _{2 x} Al ₂ (OH) _{4 x + 4} CO ₃ .nH ₂ O] used as a support in the catalyst precursor of the present invention, Lt; RTI ID = 0.0 > 300 C. < / RTI > Therefore, pre-drying at a high temperature, for example, at a temperature of 200 ° C, especially 300 ° C or more, causes the support to break, which may cause various difficulties in the later shaping step.

In one variation of the present invention, prior to shaping the catalyst precursor of step c), the dried catalyst precursor obtained in step b) is a powder having an average particle size of 100 microns, in particular 50 microns, preferably 10 microns or less . The average particle size means the size of the primary particle of the catalyst precursor, and the size of the secondary particle in which the primary particle is aggregated may be larger than the size in some cases. Crushing of the catalyst precursor can be accomplished by conventional equipment and / or means.

According to an embodiment of the present invention, the compression-molding of the catalyst precursor of step c) is carried out by mixing the above-mentioned catalyst precursor or powder thereof with an arbitrary binder in a mold having an arbitrary shape and filling it in a hydraulic press Ton) or a pelletizer. The above-described shaping pressure is not particularly limited and can be varied depending on the water content, but the pressure-formed catalyst precursor has a density of 1.0 to 2.0 g / cc, preferably 1.2 to 1.8 g / cc, particularly 1.5 to 1.7 g / The shaping pressure can be chosen to have cc.

The shaping shape may have a cube shape, a cylinder shape, a hollow cylinder shape (which may have one or more holes, preferably one to seven holes), or a pellet shape, preferably a hollow cylinder shape.

Since the above-mentioned catalyst precursor is decomposed and removed from the hydroxyl group, carbonate group and the like constituting the precursor in the firing step, the compression-molded catalyst precursor described above is reduced in both volume and weight in the firing step. At this time, since the volume consumption rate is higher than the weight consumption rate, the density of the catalyst formed body obtained by firing the above-mentioned press-formed catalyst precursor is increased. Therefore, when the density of the catalyst-precursor is less than 1.0 g / cc, the density is low and the possibility of cracking in the firing step is high. In order to achieve a density higher than 2.0 g / cc, It is difficult not only in the molding process but also after densification becomes too high or it may be difficult to obtain a sufficient specific surface area.

According to a preferred embodiment of the present invention, the catalyst precursor obtained in step b) is optionally pulverized and homogeneously mixed with the binder to carry out compression shaping. As the binder that can be used, mention may be made of an inorganic oxide precursor, for example, an alumina precursor, specifically aluminum alkoxide, aluminum hydroxide, boehmite, alumina sol, high temperature stable alumina and the like. The alumina precursor binder may be used in the form of a solution or a slurry. The above-mentioned binders can be used in an amount of not more than 40 wt%, preferably not more than 30 wt%, particularly not more than 20 wt% of the catalyst precursor.

According to an embodiment of the present invention, the firing temperature and firing time in step c) are not particularly limited, but may be, for example, 800 to 1300 占 폚, preferably 900 to 1200 占 폚, more preferably 950 to 1150 占 폚, A firing temperature of 1000 to 1150 占 폚 and a firing time of 4 to 10 hours, preferably 4.5 to 9 hours, particularly 5 to 8 hours may be mentioned.

According to the present invention, the catalyst compact obtained after firing at the firing temperature has a specific surface area of about 4 to 150 m ² / g, preferably 10 to 140 m ² / g, particularly 20 to 130 m ² / g, Can have a maximum reduction temperature of approximately 700 to 900 DEG C, a bulk density of 1.2 to 2.5 and a compressive strength of approximately 25 to 160 MPa, preferably 30 to 150 MPa, in particular 40 to 140 MPa. Specifically, the catalyst body obtained after firing at 900 to 1200 ° C has a specific surface area of approximately 4 to 150 m ² / g, a maximum reduction temperature of approximately 720 to 847 ° C, a bulk density of 1.3 to 2.2, And may have a compressive strength of 160 MPa.

According to one variant of the invention, the catalyst bodies according to the invention can be prepared by the addition of any wetting agent and / or additives (such as molding aids, lubricants, plasticizers and optionally pore-forming agents). Any conventional materials used for this purpose can be used as lubricants, plasticizers and pore-forming agents.

A number of suitable materials are mentioned in U.S. Pat. Nos. 4 826 799, 3 404 551 and 3 351 495. A carbohydrate containing a wax such as wax C fine powder PM manufactured by Hoechst AG, a fat such as magnesium or aluminum stearate or a polymer such as tylulose (methylcellulose) may preferably be used. The solids in the mixture are carefully homogenized in a suitable mixer or kneader while adding a wetting agent if necessary.

Suitable wetting agents are water, alcohols, glycols, polyether glycols or mixtures thereof. The purpose of homogenization is to prepare mixtures for subsequent molding processes. Extrusion, pelleting or compression may be applied. The type and order of additive introduction depends on the forming process used. Thus, extrusion requires a plastic material with a certain viscosity, while a weighable homogeneous material needs to be pelletized. It is routine for those skilled in the art to apply techniques applicable to this purpose, for example to agglomerate to produce flowable powders, or to adjust the viscosity to the extrusion accurately.

The catalyst body can be produced in any shape conventionally used in catalytic engineering. May be prepared in the form of extrudates, spheres, rings, spoked rings or pellets, depending on the requirements of the particular application.

The calcination of the catalyst bodies according to the present invention is carried out in a continuous type or batch type operation furnace such as a rotary tubular furnace, a conveyor belt calciner or a fixed furnace. At this time, the organic additives may also be burned together to produce a corresponding pore system.

In the present invention, the pore structure and the pore volume of the catalyst are mainly determined according to the composition of the catalyst precursor, but may be changed depending on the type and amount of the pore generating additive. The resulting final pore structure and pore volume can also be influenced by the average particle size of the catalyst alloy powder used and the type of compression applied. By suitable choice of the parameters mentioned, the structure of the shaped product can be adjusted to the requirements of a particular catalytic process.

The catalyst preforms prepared according to the present invention have a compressive strength and a specific surface area similar to those of commercial catalysts and have sufficient reactivity, compressive strength and coke resistance for application in commercial processes.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited thereto.

Preparation Example 1 (comparative)

First, as a catalyst support for mixed reforming reaction, PURAL MG30 (product of Sasol, specific surface area is at least 250 m ² / g), which is a MgAlO _x (30) support having hydrotalcite structure with MgO / Al ₂ O ₃ ratio of 3/7, (Ni (NO ₃ ) ₂ ) ₂ as a nickel precursor, and a cerium acetate solution was prepared by a cerium acetate method with a Zr / Ce ratio of 0.0 weight ratio and a Ce metal content of 4 wt% based on the MgAlO _x (30) 6H ₂ O), 12 wt% of Ce / MgAlO _x (30) support was supported on the support, and the solution was stirred at 70 ° C for 12 hours using a vacuum drier. Then, water as a solvent was removed and dried in an oven at 100 ° C for 24 hours And then calcined at 850 ° C for 6 hours to prepare a final catalyst, Ni / Ce / MgAlO _x (30).

The prepared catalyst had a specific surface area of 117 m ² / g, a pore volume of 0.34 cc / g and an average pore size of 12.4 nm.

Before carrying out the mixed reforming reaction, 0.5 g of the catalyst and 34.5 g of alpha-alumina as a diluent were uniformly mixed and charged into an Incolloy 800H reactor and hydrogenated under a hydrogen (5 vol% H ₂ / N ₂ ) atmosphere at 700 ° C for 3 The reaction was carried out after the time reduction treatment. The molar ratio of CH ₄ : CO ₂ : H ₂ O: N ₂ was adjusted to 1: 0.4 as a reactant at a reaction temperature of 850 ° C., a reaction pressure of 1.0 MPa, and a space velocity (SV) of 5000 L (CH ₄ ) : 1: 1, and the reaction was carried out by injecting into the reactor. Using a mean value for the reaction time 2 hours After 3 hours and 20 hours the conversion of methane and carbon dioxide, and _{H 2 / (2CO + 3CO 2} ) 2 H during the change of the molar ratio and the reaction 20 times / (2CO + 3CO ₂₎ The change in molar ratio is shown in Table 1 below.

Production Example 2 (Comparative)

A catalyst was prepared in the same manner as in Preparation Example 1 except that PURAL MG50 (product of Sasol, specific surface area: at least 200 m ² / m ² ), which is a MgAlO x (50) support having hydrotalcite structure with MgO / Al ₂ O ₃ ratio of 5/5, g or more) was used as a final catalyst to prepare Ni / Ce / MgAlOx (50). The specific surface area of the catalyst was 117 m ² / g, the pore volume was 0.30 cc / g and the average pore size was 13.2 nm. The conversion of methane and carbon dioxide and the conversion of H ₂ / (2CO + 3CO ₂ ) ₂ were performed using the above catalysts by performing the mixed reforming reaction in the same manner as in Example 1 and using an average value for 2 hours after 3 hours and 20 hours, The changes in the molar ratio are shown in Table 1 below.

Preparation Example 3 (comparative)

A catalyst was prepared in the same manner as in Example 1 except that PURAL MG30 (product of Sasol Co., Ltd.) having a hydrotalcite structure MgAlO _x (30) having a MgO / Al ₂ O ₃ ratio of 3/7 had a specific surface area of at least 250 m ² / g more) was used, the MgAlOx (30) so that the box with cerium acetate and zirconium nitrate ratio of 0.25 weight ratio Zr / Ce using the impregnation method for a support, and MgAlO _x (30), the support prepared Ce-Zr (Ni (NO ₃ ) ₂ .6H ₂ O) as a nickel precursor, so that the weight of nickel is supported so as to be 18 wt%, and 15 wt% of nickel is supported on Ce-Zr / MgAlO _x The mixture was stirred at 70 ° C for 12 hours by using a vacuum drier, and then water as a solvent was removed. The resulting product was dried in an oven at 100 ° C for 24 hours or more and then calcined at 850 ° C for 6 hours to obtain a final catalyst, Ni-Ce-Zr / MgAlO _x 30). At this time, the specific surface area of the catalyst was 85 m ² / g, the pore volume was 0.21 cc / g and the average pore size was 11.5 nm.

The conversion of methane and carbon dioxide and the conversion of H ₂ / (2CO + 3CO ₂ ) ₂ were performed using the above catalysts by performing the mixed reforming reaction in the same manner as in Example 1 and using an average value for 2 hours after 3 hours and 20 hours, The changes in the molar ratio are shown in Table 1 below.

number CH ₄ conversion
(%) CO ₂ conversion
(%) H ₂ /
(2CO + 3CO ₂₎ Manufacturing 1 86 → 84 59 → 58 0.87 - > 0.86 Manufacturing 2 85 → 84 55 → 59 0.87 - > 0.86 Manufacturing 3 84 → 83 58 → 56 0.86 - > 0.86

Example 1

221 g of cerium nitrate [Ce (NO ₃ ) ₃ .H ₂ O] and 206 g of water, 1206.4 g of nickel nitrate [Ni (NO ₃ ) ₂ .6H ₂ O] and 1126 g of water were mixed, And stirred to obtain a homogeneous mixture.

1750 g of a hydrotalcite MgAlO _x (30) support (PURAL MG 30) having a MgO / Al ₂ O ₃ ratio of 3/7 as a catalyst support for mixed reforming reaction was impregnated with the above mixture while stirring, And dried for 24 hours or more to obtain a catalyst precursor.

Using the pelletizer, the obtained catalyst precursor was shaped into a 1-spherical hollow cylinder having an outer diameter of about 10.2 mm, an inner diameter of about 5.0 mm, and a height of about 6.7 mm, wherein the density was 1.55 g / cc or 1.66 g / cc (see Fig. 1).

The obtained 1-spherical hollow cylindrical shaped body was heated to a sintering temperature (900 ° C, 1000 ° C, 1100 ° C, 1200 ° C) at a rate of 3 ° C per minute and then calcined for 6 hours to obtain NiO-CeO _x -MgO -Al ₂ O ₃ composition was prepared. When the obtained catalyst is a final reduction _{NiO: CeO: MgO: Al 2} O 3 = 12: 4: 25.2: has a composition ratio (% by weight) of 58.5.

Table 2 shows the physical properties of the resulting catalyst body obtained by firing a catalyst body having a molding density of 1.55 g / cc.

Catalyst number Firing temperature TGA weight reduction rate (%) NiO size
(nm) Specific surface area
(m ² / g) Bulk density
(g / cc) Compressive strength
(MPa) 1-1 900 ℃ 15.0 12.0 97.9 1.35 28.6 1-2 1000 ℃ 14.5 15.8 33.1 1.57 39.6 1-3 1100 ℃ 13.4 19.7 11.3 1.90 55.0 1-4 1200 ℃ 9.0 27.4 5.5 2.14 74.9

Table 3 below shows the physical properties of a catalyst compact obtained from a catalyst body having a molding density of 1.66 g / cc.

Catalyst number Firing temperature (캜) Compressive strength (MPa) 1-5 9000 54.9 1-6 1000 67.8 1-7 1100 122.3 1-8 1200 153.6

From the results of Tables 2 and 3, it was confirmed that the higher the initial forming density and the higher the firing temperature, the more the compressive strength increases. On the other hand, the higher the firing temperature, the smaller the specific surface area. Therefore, it is important to select the initial molding density and firing temperature in an appropriate range to control the physical properties of the catalyst body.

Test Example 1

The catalyst prepared in Example 1 was subjected to a carbon dioxide reforming reaction of methane under the following operating conditions for the internal coke resistance test:

- CH ₄ : CO ₂ = 1: 1 (space velocity SV = 30,000 mL (CH ₄ ) / gcat / hr)

- CH ₄ = 100 ml / min, CO ₂ = 100 ml / min, N ₂ = 50 ml / min (CH ₄ : CO ₂ : N ₂ = 1: 1: 0.5)

- P = 0.5 MPa, T = 800 ℃, 12 hours operation

- the amount of _{catalyst: 200 mg [Inert (Al 2} O 3): 1200 mg]

Wherein the operating condition is a speed condition 20 times higher than those of typical commercially available operating conditions _{(SV = 1,500 / CH 4)} . Table 4 shows the conversion ratios of methane and di-ring carbon, H ₂ / (2CO + 3CO ₂ ) and CO / (CO + CO ₂ ) in the initial operation (1 hour) ₂ ) compositional ratios were described.

catalyst
number CH ₄ conversion CO ₂ conversion H ₂ /
(2CO + 3CO ₂₎ CO /
(CO + CO ₂ ) equilibrium 84.6% 69.4% 0.46 0.82 1-1 80.1? 76.3 93.8? 90.7 0.40 - > 0.38 0.97 - > 0.95 1-2 79.5? 77.5 93.1? 93.0 0.40 - > 0.39 0.96 - > 0.96 1-3 75.5? 70.6 91.1 → 89.3 0.38 - > 0.35 0.95 - > 0.94 1-4 75.3 -> 71.7 90.0? 86.7 0.38 - > 0.36 0.94 - > 0.92

In Table 4, the equilibrium values of CH ₄ conversion and CO ₂ conversion are theoretical values, showing good process adaptability of the present catalysts and showing that the low temperature calcined catalyst bodies exhibit relatively better activity. It is thought that the lower the firing temperature, the larger the specific surface area and thus the larger the active Ni sites.

For reference, it is difficult to directly compare the values obtained using the catalysts of Production Examples 1 to 3 (Table 1) with the values in Table 4, because the operating conditions are different from each other, Since the powder catalyst of Test Example 1 can not be applied under the conditions of use.

Meanwhile, FIG. 3 shows temperature-programmed reduction (TPR) analysis results of the catalyst formed bodies 1-1 to 1-4. The results of the TPR analysis show that the higher the calcination temperature, the higher the reduction temperature, indicating that NiOx species strongly bind to the support material in the catalyst of the present invention. Generally, it is known that the stronger the bond between the support material and the NiOx species in the catalyst, the better the inner coke property. In the catalyst of the present invention, the higher the sintering temperature, the higher the reduction temperature. .

According to the results of Examples and Test Example 1, the higher the firing temperature, the lower the catalytic performance (conversion ratio) of the catalyst formed body, while the better the coke resistance. Considering these results as a whole, it can be seen that the catalyst shaped body of the present invention obtained by high-temperature firing can have a high coke resistance, and as a result, the catalytic reaction process can be operated more efficiently.

Test Example 2

A mixed reforming reaction was performed on the catalyst prepared in Example 1:

(Space velocity 5,000 mL (CH ₄ ) / g cat / hr) - CH ₄ : CO ₂ : H ₂ O: N ₂ = 1.17: 0.36:

- CH ₄ = 51.01 ml / min, CO ₂ = 15.06 ml / min, H ₂ O = 69.59 ml / min, N ₂ = 26.00 ml / min

- Operation at P = 1.1 MPa, T = 800 ℃, 48 hours

- the amount of _{catalyst: 612 mg [Inert (Al 2} O 3): 2 g]

Wherein the operating condition is a speed condition three times compared to a typical commercially available operating conditions _{(SV = 1,500 / CH 4)} . Table 5 shows the conversion ratios of methane and di-ring carbon, H ₂ / (2CO + 3CO ₂ ) and CO / (CO + CO ₂ ) composition ratios during the reaction time from 10 hours to 48 hours under the above- Are described.

CH ₄ conversion
(%) CO ₂ conversion
(%) H ₂ /
(2CO + 3CO ₂₎ CO /
(CO + CO ₂ ) equilibrium 68.7% 11.8% 0.901 0.729 1-1 66.46 38.64 0.882 0.807 1-2 64.87 35.83 0.873 0.796 1-3 67.20 36.60 0.887 0.802 1-4 65.13 36.12 0.875 0.796

Example 2

Using a hydraulic press, the catalyst precursor obtained in Example 1 was pressed at a pressure of 3 tons for 30 seconds to obtain a cylindrical catalyst body having a diameter of about 10.2 mm and a height of about 5.0 mm.

The obtained cylindrical body was fired for 6 hours to produce a cylindrical catalyst body as shown in Fig.

Example 3 and Comparative Examples 1 to 5

The same procedure as in Example 1 was carried out using a pelletizer, but the catalyst precursor was dried at different temperatures and the catalyst body was calcined at 1100 ° C to prepare catalyst bodies.

The drying temperature, the molding density, the sintering temperature, the plastic density and the compressive strength of the obtained catalyst bodies are shown in Table 6 below.

number Drying temperature
(° C) Forming density
(g / cc) Firing temperature
(° C) Plastic density
(g / cc) Compressive strength Example 3 120 1.35 1100 1.55 31.7 Comparative Example 1 200 1.50 1100 1.81 27.7 Comparative Example 2 300 Not measurable 1100 1.72 16 Comparative Example 3 500 Not measurable 1100 1.73 15.4 Comparative Example 4 700 Not measurable 1100 1.69 14.1 Comparative Example 5 1100 Can not be formed 1100 Can not be formed Can not be formed

Table 6 shows that when the obtained catalyst precursor is dried at an excessively high temperature, it is difficult to form (shape) the pelletizer, and further processing can not proceed to such an extent that molding density can not be measured even if it is shaped .

Examples 4 to 5 and Comparative Examples 6 to 10

A hydraulic press was used in the same manner as in Example 2 except that the catalyst precursor was dried at 200 ° C, 300 ° C, 500 ° C, and 700 ° C, respectively, and the catalyst body was calcined at 1100 ° C to prepare catalyst bodies .

The drying temperature, the molding density, the sintering temperature, the plastic density and the compressive strength of the obtained catalyst bodies are shown in Table 7 below.

number Drying temperature
(° C) Forming density
(g / cc) Firing temperature
(° C) Plastic density
(g / cc) Compressive strength
(MPa) Example 4 120 1.80 1100 2.37 159 Example 5 150 1.70 1100 2.22 119 Comparative Example 6 200 1.76 1100 2.35 124 Comparative Example 7 300 1.47 1100 2.11 107 Comparative Example 8 500 1.54 1100 2.56 - Comparative Example 9 700 1.48 1100 2.49 - Comparative Example 10 1100 1.59 1100 1.63 38

The present invention relates to a synthesis gas composition (H ₂ / CO = 2) which is easy for methanol synthesis or Fischer-Tropsch reaction through a mixed reforming reaction which simultaneously performs the carbon dioxide reforming reaction (CDR) of methane and the steam reforming reaction ), And it is possible to manufacture a catalyst shaped article instead of being limited to simple catalyst powder production. It is believed that the production of the catalyst body can contribute to the development of a process for economical utilization of carbon dioxide in the industrial field.

Claims (8)

a) a Ce precursor or a Ce-Zr precursor is supported on a MgAlOx support, and a Ni precursor is supported simultaneously or successively,
b) drying the resultant Ni precursor / Ce precursor or a mixture of Ce-Zr precursor / MgAlOx at 100-150 ° C to obtain a catalyst precursor,
c) shaping the dried catalyst precursor to a density of 1.0 to 2.0 g / cc to obtain a catalyst body,
d) calcining the obtained catalyst body at a temperature of 850 to 1250 占 폚 to obtain a catalyst compact having a compressive strength of 25 to 160 MPa and a specific surface area of 4 to 150 m ² / g , And a mixed reforming reaction of methane. The method of claim 1, wherein the Ce precursor is used in an amount of 3 to 20 wt% based on the total weight of the catalyst precursor. The method according to claim 1, wherein the Ni precursor is used in an amount of 5 to 20% by weight based on the total weight of the catalyst precursor. The method according to claim 1, wherein the catalyst precursor in step b) is dried to have a moisture content of less than 30% by weight. The method for producing a nickel-containing catalyst formed body for a mixed reforming reaction of methane according to claim 1, wherein the catalyst precursor obtained in the above-mentioned step b) is ground to an average particle size of 100 microns. The method according to claim 1, wherein the catalyst precursor is homogeneously mixed with 10 to 30% by weight of an inorganic oxide precursor as a binder and is subjected to compression molding so as to produce a nickel-containing catalyst preform for a mixed reforming reaction of methane . A nickel-containing catalyst molded article for mixed reforming reaction of methane obtained by the method according to claim 1. The nickel-containing catalyst formed body for mixed reforming reaction of methane according to claim 6, characterized by having a hollow cylinder shape.

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