KR100927105B1 - Catalyst for autothermal reforming of methane for producing synthetic gas??2??????for Fischer­Tropsch process, catalyst layer structure for reactor and manufacturing method to produce synthetic gas for Fischer­Tropsch process by using the same - Google Patents

Abstract

The present invention relates to a methane autothermal reforming catalyst used in the synthesis gas for Fischer-Tropsch liquefaction process, a mesh type catalyst layer using the same, and a method for producing the synthesis gas for Fischer-Tropsch using the same,

Its main purpose is the partial reaction of methane or natural gas as the main reaction and the addition of hydrogen and carbon monoxide by the steam reforming reaction and the reverse water gas shift reaction. In the conversion to the present invention, the present invention provides a catalyst and a catalyst layer required for obtaining a hydrogen to carbon monoxide ratio (H ₂ / CO 2) suitable for the Fischer-Tropsch process and reaction conditions using the same.

The composition of the present invention is a high surface area alumina carrier, a catalyst for preparing a synthesis gas for the Fischer-Tropsch liquefaction process composed of 2 to 4 wt% of palladium metal relative to the total weight of the catalyst, and a catalyst having a irregular channel in a mesh metal plate. The catalyst layer is laminated in a form that can be easily adjusted according to the amount, and the synthesis gas production method using the same features the technical idea.

Autothermal reforming, palladium, Fischer-Tropsch syngas, mesh catalyst layer, catalytic partial oxidation

Description

Methane autothermal reforming catalyst used in the synthesis gas for Fischer Tropsch liquefaction process, mesh type catalyst layer using the same, and method for producing synthetic gas for Fischer Tropsch using the same {H2 / CO ≒ 2) for Fischer Tropsch process, catalyst layer structure for reactor and manufacturing method to produce synthetic gas for Fischer Tropsch process by using the same}

The present invention relates to a methane autothermal reforming catalyst used in a synthesis gas for Fischer-Tropsch liquefaction process, a mesh type catalyst layer applied to the reactor, and a method for producing a synthesis gas for Fischer-Tropsch using the same, The catalyst composition required in the syngas production process for the Ropsch liquefaction process is high, the target composition of hydrogen and carbon monoxide is close to 2, and the catalyst composition increases the selectivity of hydrogen and carbon monoxide. It is about a method of producing hydrogen and carbon monoxide suitable for the Fischer-Tropsch reaction by changing the structure of the catalyst structure in the form of an irregular flow path on the support and the conditions such as water, oxygen, and space velocity. .

In addition to fuel cells and small hydrogen generators, fuel reformers are in demand as reformers for natural gas and methane for syngas production. In particular, as the development of gas fields, which are difficult to develop due to economic reasons such as small and remote gas wells (stranded or remote gas wells), is being burned, the availability of them is increasing.

As of 2004, the amount of gas burned was 10 billion ft ³ per day, which is 25% of the EU's daily use or 17% of the US's use of gas per day. When classifying under the current criteria reserves 1 trillion ^{ft 3 (1 Trillion cubic feet,} Tcf) with a small gas fields, gas fields, depending on the size of about 1,400 that were investigated are scattered around the world.

Since methane, which is the main component of natural gas, has a very large binding energy of carbon atoms and hydrogen atoms of methane by forming an SP ₃ hybrid orbit, very large energy is required to activate methane.

There are various methods of reforming fuel using methane. Generally, 1) steam reforming, 2) partial reforming, and 3) autothermal reforming are used.

 In the case of steam reforming, the reaction occurs without a catalyst at 1300 ° C. or higher, but when a catalyst such as Pt or Rh is used, the reaction occurs at 800 ° C., and the hydrogen and carbon monoxide ratio of the produced synthesis gas is known to be about 3. However, this method requires about three times as much steam as methane, a strong endothermic reaction, which consumes a lot of energy, and the hydrogen-carbon monoxide ratio is not suitable for Fischer-Trosch syngas.

In the case of partial oxidation reforming, it is advantageous to compact the catalyst volume to about 1/100 of the steam reforming on the basis of the same amount of treatment, but also the hydrogen to carbon monoxide ratio of 1.5 is also not suitable.

To compensate for this, the steam reforming reaction, which is an endothermic reaction, and the partial oxidation reforming reaction, which is an exothermic reaction, occur simultaneously, thereby reducing operating energy and controlling the supply ratio of reactants, water and oxygen. Autothermal reforming, which can control the ratio of hydrogen and carbon monoxide as a product, and can produce hydrogen and carbon monoxide ratio of about 2, has emerged as an important application method, and thus can meet these characteristics. Is the reason for autothermal reforming.

Patent trends investigated for syngas production for the Fischer-Tropsch process show that gas liquefaction technology in generators has been on the rise since the 1990s, with the most active patent activity in the US, and syngas in Japan. The manufacturing sector dominated, while other regional patents prevailed in the Fischer-Tropsch process. Within each sector, there was a trend toward higher proportions in the process than in the production of catalysts. This is important for good catalysts, but technology such as reactor structure, reaction period connection, and operating conditions for high efficiency of reforming equipment is also important.

In the case of syngas production, representative patents cited widely include catalyst parts (Ni-based US 5,368,835, precious metals-based US 6,293,979, catalyst structure US 4,793,904), and thermal reforming in the process field is US 5,023,276 (June 11, 1991, ENGELHARD CORP. , Partial hydrogen oxidation, US 6,016,868 (2000, 1.25, World Energy Systems), and steam reforming were US 4,579,985 (April 1, 1986, ENGELHARD CORP.).

In particular, the patent on noble metal catalysts used in syngas production (US 6,293,979) describes a technique using a catalyst in which cobalt oxide is deposited on a support in which Be, Mg, Ca or a mixture thereof is pre-coated upon conversion of methane or natural gas into syngas. The autothermal reforming (US 5,023,276) patent is a technique for producing hydrogen enriched gas from hydrocarbon-based raw materials using a catalytic partial oxidation method and a selective steam reforming method. In addition, although a catalyst (USP 6,293,979) supporting an alkali metal on the outer surface of an inert support and then co-precipitating nickel and cobalt has been disclosed, many reports have been reported on an effective autothermal reforming device. The results of studies on the catalytic activity and the suitable composition ratio of high activity have not been reported.

When used in reformers, the shape of the catalyst is usually divided into powder, pellet and monolithic. In addition, the monolith type catalyst, which has a honeycomb-shaped rod-shaped void space, is easily transferred through the wall, so that the temperature of the catalyst is uniform and the pressure loss is low. (Ceramic monolith, US 5,648,582; zirconia (ZrO ₂ ) based monolith, US 5,639,401; metal monolith, US 5,786,296, 5,648,582 and 6,221,280 B1, EP 303438, Feb. 1989, Freni et al., J. of Power Sources 87 ( 2000), 28-38). Taking advantage of these advantages, the more complementary method is a method in which cells of metal meshes are arranged in an irregular arrangement so that the reaction gas can be spatially induced rather than linearly, thereby improving reactivity.

As an example of a method of starting the catalytic partial oxidation reaction, which is an exothermic reaction, US Pat. No. 6,221,280 B1 suggests a method of raising the temperature of the reactants above the initiation temperature by an external heating furnace. However, catalytic partial oxidation reaction apparatus including an external furnace has a disadvantage of low energy efficiency. Another start-up method described in U.S. Patent No. 5,648,582 is the complete combustion of methane or ammonia by a sparker and the heat of combustion to raise the temperature of the catalyst to about 1000 ° C, followed by injection of an appropriate ratio of methane and oxygen mixture. There is a way to start the catalytic partial oxidation reaction. However, the use of sparkers has the problem that there is a risk of catalyst damage due to explosion and high temperature.

Another use of the metal monolith, which is also a catalyst structure with excellent thermal conductivity, is a reaction starting device of a catalytic partial oxidation reactor. When electric wires are connected at both ends of the metal monolith and electricity is supplied, the metal monolith is heated by the electrical resistance, and the gas flowing through the hole of the monolith is also heated (T. Kirchner et al., Chemical Engineering Science, Vol. 51, page 2409). , 1996; SR Nakouzi et al., AIChE Journal, Vol. 44, 184 page, 1998) Examples of the use of an electric heater as a starting device for catalytic partial oxidation reaction include Korean Patent Nos. 10-0558970 and US 10 / 735,257.

For this reason, this patent utilizes metal monoliths as the metal mesh catalyst structure and starting device mentioned above.

An object of the present invention for solving the above problems is a partial oxidation reaction of methane or natural gas as the main reaction and the addition of steam reforming reaction and (reverse) water gas shift reaction, ( R) WGS} to convert hydrogen and carbon monoxide, providing the catalyst necessary to obtain a hydrogen and carbon monoxide ratio (H ₂ / CO 2) suitable for the Fischer-Tropsch Process.

It is an object of the present invention to partially hydrogenate methane or natural gas as a main reaction and to add hydrogen by means of steam reforming and (reverse) water gas shift reaction (R) WGS}. While converting to carbon monoxide, the catalyst required to obtain the hydrogen and carbon monoxide ratio (H ₂ / CO ≒ 2) suitable for the Fischer-Tropsch Process is stacked on the support so that irregular flow paths are generated in the reactor. It is to provide a catalyst layer structure of.

It is an object of the present invention to partially hydrogenate methane or natural gas as a main reaction and to add hydrogen by means of steam reforming and (reverse) water gas shift reaction (R) WGS}. The present invention provides a method for preparing a synthesis gas using a catalyst layer necessary to obtain a hydrogen and carbon monoxide ratio (H ₂ / CO 2) suitable for the Fischer-Tropsch process while converting to carbon monoxide.

The present invention to achieve the object as described above and to solve the conventional drawbacks in the catalyst for methane autothermal reforming for the production of Fischer-Tropsch liquefaction process synthesis gas (H ₂ / CO ≒ 2),

High surface area alumina carrier; It is achieved by providing a methane autothermal reforming catalyst used in the manufacturing process of the synthesis gas for the Fischer-Tropsch liquefaction process characterized in that the composition is calcined 2 to 4wt% relative to the total weight of the carrier and the catalyst catalyst.

The high surface area alumina carrier is gamma alumina (γ-alumina), and the specific surface area is characterized by using a larger than 100m ² / g.

The firing conditions are characterized in that carried out at 650 ~ 900 ℃ in an air atmosphere.

In addition, the present invention is to install the electric heater as a starting device in the inner front end of the autothermal reforming reactor case insulated with a high temperature insulation material for the production of Fischer-Tropsch liquefaction process synthesis gas (H ₂ / CO ≒ 2), A thermocouple mounted at the rear end of the heater and installed at the front end of the electric heater; A thermocouple between the electric heater and the washcoat catalyst layer; In the catalyst layer structure used in the autothermal reforming reactor further comprises a thermocouple installed at the rear end of the washcoat mesh type catalyst layer,

The catalyst layer has a plurality of mesh types provided with at least two supports bent upwardly in the autothermal reforming reactor case spaced at a predetermined interval in the bottom space of the electric heater, and the catalyst coated with palladium on the support was washed. It is achieved by providing a mesh catalyst layer using a methane autothermal reforming catalyst used in the synthesis gas production process for the Fischer-Tropsch liquefaction process, characterized by consisting of a mesh catalyst layer formed by laminating a metal plate.

The mesh metal plate constituting the mesh catalyst layer is characterized in that about 15 wt% of the total amount of the mesh metal plate is washed with the palladium-containing catalyst.

The mesh metal plate constituting the mesh catalyst layer is composed of an alloy plate which is not deteriorated at about 1000 ° C. such as iron-chromium-aluminum, nickel-chromium alloy, or nickel-chromium-aluminum having a thickness of 50 to 100 micrometers. It is done.

The area opening% of the mesh metal plate constituting the mesh catalyst layer is characterized by using 60 to 70%.

The mesh metal plate constituting the mesh catalyst layer is laminated so that the mesh holes of the mesh metal plate adjacent up and down are arranged to have an irregular flow path without forming a vertical flow path.

In addition, the present invention is to install the electric heater as a starting device in the inner front end of the autothermal reforming reactor case insulated with a high temperature insulation material for the production of Fischer-Tropsch liquefaction process synthesis gas (H ₂ / CO ≒ 2), A thermocouple mounted at the rear end of the heater and installed at the front end of the electric heater; A thermocouple between the electric heater and the washcoat catalyst layer; It is provided with an autothermal reforming reactor further comprising a thermocouple installed at the rear end of the washcoat mesh type catalyst layer,

Mixing one of oxygen or air and one of steam or methane or natural gas supplied in a separate feed line;

Heating a monolithic type electric heater for starting;

Later, a plurality of mesh-shaped metal plates wash-coated with a catalyst (PdO / Al ₂ O ₃ ) supported on alumina having a high surface area of palladium were mixed with one of oxygen or air, steam and one of methane or natural gas. Supplying the packed mesh type catalyst layer to catalytic partial oxidation;

After the catalytic partial oxidation reaction, the catalytic partial oxidation, steam reforming reaction and water gas transfer reaction are continued without external energy supply to produce hydrogen and carbon monoxide at the optimum ratio and high yield for the Fischer-Tropsch liquefaction reaction. But

Methane or natural gas supplied to the catalytic partial oxidation reaction Fischer-Tropsch liquefaction process synthesis gas manufacturing process, characterized in that configured to be injected when the thermocouple temperature of the rear end of the mesh catalyst layer reaches 200 ℃ ~ 250 ℃ region It is achieved by providing a method for producing a synthesis gas for Fischer-Tropsch using a methane autothermal reforming catalyst used in.

The step of catalytic partial oxidation is characterized in that the catalytic partial oxidation reaction is controlled by controlling the amount of catalyst by adjusting the number of stacked layers of the mesh metal plate laminated on the mesh type catalyst layer.

The catalyst of the present invention is similar to the conventional four-component catalyst when the methane autothermal reforming reaction is carried out using various catalysts combined with various components, supported on alumina, and synthesized through calcination and reduction. Only palladium having an active activity has the advantage of being a catalyst having economical and high activity and having a hydrogen and carbon monoxide generation ratio close to two by providing a supported catalyst.

In addition, the catalyst layer structure of the present invention has the advantage of using the catalyst on which only palladium is loaded to cause the reaction gas flow path irregularly to increase the reactivity and easily control the desired amount of catalyst.

In addition, the Fischer-Tropsch synthesis gas production method using the catalyst layer structure using the catalyst containing only palladium of the present invention after the catalytic partial oxidation reaction, catalytic partial oxidation, steam reforming reaction and water gas transition reaction is continued without external energy supply As a result, the production cost is reduced when hydrogen and carbon monoxide are produced at the optimum ratio and high yield for the Fischer-Tropsch liquefaction reaction, and it is a useful invention having the advantages of ensuring ease of operation.

According to the present invention, a catalyst in which palladium is supported on a surface of a highly active alumina carrier is produced by an impregnation method.

Impregnation is carried out by a general method. First, high surface area alumina is added to water and stirred, and then a palladium precursor and alumina sol are added and stirred. It is then fired at 121-900 ° C [25 ° C → 121 ° C (1 hour) → 121 ° C (30 minutes) → 232 ° C (1 hour) → 232 ° C (30 minutes) → 565 ° C (2 hours) → 565 ° C (30 Minute) → 900 ° C. (2 hours) → 900 ° C. (30 minutes) → 25 ° C. (4 hours)] to obtain a catalyst.

The composition of the catalyst proposed in the present invention is a high surface area alumina (γ-alumina) carrier, 2 to 4 wt% of the palladium metal based on the weight of the carrier and the catalyst as a whole.

The reason for limiting the palladium composition ratio is that the reaction progress is not sufficient at 2wt% or less, thereby preventing the function as a catalyst, thereby limiting the minimum supported amount to 2wt%, due to the sintering phenomenon when the metal is supported in excess of the specific surface area of the carrier. The content of the catalyst was limited to 4 wt% because the catalytically active point could be reduced.

In addition, the high surface area alumina refers to gamma alumina.

As the alumina is synthesized and fired, it is divided into alpha phase alumina, beta phase alumina, and gamma phase alumina by firing temperature. The largest surface area is gamma alumina. The specific surface area of these three aluminas is as follows.

Alpha alumina: <10 m ² / g

Beta alumina: 10 to 100 m ² / g

gamma alumina:> 100m ² / g

The catalyst prepared above is subjected to a calcination process. The reason for the calcination process is to remove and remove unnecessary components or lubricants left in the catalyst at a high temperature while supporting the active material or forming the catalyst.

Firing conditions are performed at 650 ~ 900 ℃ in an air atmosphere. In this case, the reason for limiting to 900 ° C. is that at least 650 ° C. should be fired in order to remove unnecessary components and lubricants, and the reaction conditions do not exceed this temperature. As the carrier surface area decreases, the number of active site distributions decreases.

The firing time is also 30 minutes to 2 hours at each temperature, giving too much time to remove unnecessary components and lubricants, resulting in sintering of the supported metal and phase change of the carrier. To prevent this.

 The catalyst is washed and laminated on a metal mesh plate, and the metal mesh plate is not a honeycomb or monolithic form in which the reaction gas flow path is straight from top to bottom, but is used in that it is laminated on a support to cause an irregular flow path.

The washcoat metal mesh catalyst layer is configured to fill a high temperature insulation material in the space between the walls of the autothermal reforming reactor case to prevent heat loss of the washcoat metal mesh catalyst layer.

In addition, an electric heater as a starting device is installed at the front end of the autothermal reforming reactor, and a metal mesh catalyst layer is stacked and mounted at the rear end. A thermocouple T1 installed at the front end of the electric heater; A thermocouple (T 2) between the electric heater and the washcoat catalyst layer; It further comprises a thermocouple (T3) provided on the rear end of the washcoat mesh type catalyst layer (see Fig. 2).

The reactor body is configured to supply a gas containing methane or natural gas and steam containing oxygen or air selectively.

The reactor is configured to inject oxygen (O ₂ ) to carbon volume ratio at a ratio of 0.5 to 0.67. The reason for the numerical limitation is that if the ratio is smaller than this, the amount of heat generated by combustion is low, so that the temperature of the catalyst bed is low, so that the conversion rate of methane or natural gas may be low, or the hydrogen fraction may be high. This is because coke may form in the catalyst layer and cause catalyst deactivation.

The steam (H ₂ O) is configured to be injected at a ratio of steam to carbon volume ratio of 0.5 to 1.0. Thus numerical limitation reason is coke is created / deposited is increased equal to or greater than 2 ratio of high and a problem with catalyst deactivation and the increase in pressure, H ₂ / CO is less than the ratio of the Fischer-Tropsch swiyong the synthesis gas Because it is difficult.

In addition, the present invention was prepared by comparing various components of the catalyst of the present invention and the comparative catalysts. Looking at the composition ratio of each element, the catalyst PdO of the present invention was present in a weight fraction (wt%) of the total catalyst weight of 2 to 4 wt. %, And BaO of 8.8 to 14 wt% of the catalysts to be compared, 34.7 to 38.6 wt% of CeO ₂ , 1.1 to 2 wt% of SrO and gamma alumina as the support.

TABLE 1 Contents of the catalysts of the present invention and comparative catalysts

The catalyst layer in which the precious metal is washcoat on the metal mesh plate of the present invention uses a space velocity of 36,000-144,000 hr ^-1 . The reason for using the space velocity in the above section is that in the case of partial oxidation reaction, if the space velocity is low, the probability of complete oxidation is high, and if it is too high, an unreacted result may be obtained.

In addition, the present invention is configured such that the methane or natural gas injected into the reactor is injected when the rear end temperature (T3) of the catalyst bed reaches the 200 ℃ ~ 250 ℃ region. The reason for limiting the temperature is that partial oxidation does not start at a temperature below T3 of methane or natural gas. This is because the reaction proceeds abruptly at higher temperatures.

Referring to the apparatus filled with the catalyst layer as described above in detail, the reactor gas injected into the reactor is one of methane or natural gas and one of oxygen or air and a mixture of steam is sequentially injected to reach the catalyst bed Is completely oxidized, and the catalytic partial oxidation reaction is started in a short time as the temperature of the partial oxidation catalyst layer rises due to the heat generated.

When the partial oxidation reaction is started after the injection of methane or natural gas, the washcoat metal mesh catalyst layer 11 and the rear end temperature rise, and the conversion of methane or natural gas proceeds further, and the Fischer-Tropsch liquefaction reaction is performed. It is converted to hydrogen and carbon monoxide at optimum rates and high yields.

The amount of the washcoat used in the mesh catalyst layer was 15 to 20wt% of the mass of the metal mesh plate by weight ratio. The reason for the numerical limitation as described above is that the lower the lower limit value, the greater the uncoated portion of the metal mesh type catalyst layer, and the lower the efficiency. If the upper limit is higher than the upper limit value, the uniformity is not obtained.

The mesh metal plate constituting the mesh catalyst layer is 50 to 100 micrometers The thick one was used. The reason for the numerical limitation as described above is that lower than the lower limit value workability is easily deformed, if higher than the upper limit value to fill the unnecessary volume in the reactor.

The area opening% of the mesh metal plate constituting the mesh catalyst layer was 60 to 70%. The reason for the numerical limitation as described above is that it is difficult to control the pressure if it is lower than the lower limit value.

The reaction process by a structure in the above apparatus is as follows.

When the electric heater is turned on and the oxygen and water are supplied, the temperature inside the reactor starts to rise. When the T 3 temperature is above 200 ^o C, before the temperature reaches 250 ^o C, methane or natural gas is injected and the catalytic partial oxidation reaction is started.

The exothermic energy by partial catalytic oxidation acts as a heat source of the steam reforming process, which is an endothermic reaction by steam in the mesh catalyst layer, thereby enabling the autothermal reforming reaction process.

The oxygen-containing gas is a gas having an increased oxygen content in air, and the oxygen content (volume ratio) is from 100% oxygen which is completely pure oxygen to 21% oxygen. The reason for the numerical limitation is that oxygen is required as a fuel required for partial oxidation of the feed gas, since 100% oxygen may be used and oxygen in the air (21%) may be used.

Hereinafter, the configuration and the operation of the embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 shows the results of autothermal reforming of the catalysts used for the catalyst of the present invention. As shown, PdO / Al ₂ O ₃ is superior to other types in the methane conversion and H ₂ / CO ratios. Only PdO / Ce / Ba / Sr / Al ₂ O _{3 shows} similar activity, but considering the workability and economic aspects, PdO / Al ₂ O ₃ catalyst is suitable as autothermal reforming catalyst. This is because the number of components used is reduced and the number of steps in the manufacturing process is significantly reduced. That is, according to the present invention, after the sol made by mixing each component in alumina, and then calcined and dried, and then calcined-dried by using Pd precursor, the synthesis process ends and the process is drastically reduced.

Figure 2a is an autothermal reforming reactor used to confirm the activity of the catalysts for the present invention, Figure 2b is a structural diagram of a mesh type catalyst layer mounted to the autothermal reforming reactor used to confirm the activity of the catalysts for the present invention I'm doing it

 In the present invention, when the reactor is injected into the autothermal reforming oxidation reactor, the first place is an electric heater (10), which prevents short circuits and short circuits at both ends of the metal monolith and welds the electrode, and the metal monolith waves the thin metal plate. It was made by winding the form and overlapping the plate.

At the bottom of the electric heater 10, a mesh catalyst layer 11, which is installed at a predetermined interval by the space part, is inserted into the support 12, and the catalyst layer is a metal mesh type in which the catalyst is washcoat.

The space between the washcoat metal mesh catalyst layer 11 and the wall of the autothermal reforming reactor case 14 fills the high temperature insulation material 13 to prevent heat loss of the washcoat metal mesh catalyst layer 11.

Three thermocouples (thermocouples, T1, T2, T3) are installed in the combination process, where T1 measures the front end of the electric heater 10 and T2 measures the temperature between the electric heater 10 and the metal mesh catalyst layer 11. In addition, T3 is used to measure the rear end of the metal mesh catalyst layer 11, and T3 is used as an important indicator for determining when to inject methane or natural gas and to operate the reactor.

The material of the reactor and heat exchanger of the present invention can be made of a low cost material such as stainless steel.

Hereinafter, the configuration and effects of the present invention will be described in more detail with reference to preferred embodiments. However, these embodiments do not limit the scope of the present invention.

Example 1 Preparation of Metal Mesh Type Catalyst Layer

The catalyst of the present invention is a catalyst in the form in which the precious metal is washcoat to the metal mesh. The metal mesh catalyst layer prepared in this example used an iron-chromium-aluminum alloy (FeCralloy) plate having a thickness of 100 micrometers to have high temperature durability, and the area opening percentage was 60%.

The prepared metal mesh catalyst layer was oxidized in advance to improve adhesion between the ceramic-based washcoat material and the metal mesh.

Specifically, palladium nitrate (Pd nitrate), which is a precursor having a weight ratio of 2 to 4 wt% of palladium in a slurry of high surface area alumina powder mixed in distilled water, has a palladium precursor of about 2.75 Grams), water, and alumina sol, then mix thoroughly using a stir bar.

After immersing and coating the metal mesh one by one or several in the slurry in which the noble metal precursor is dissolved, and firing up to 900 ℃ to complete the metal mesh coated with the precious metal.

The washcoat amount of the catalyst prepared in the embodiment of the present invention is about 15 to 20wt% of the total mesh and the content of palladium noble metal is 2 to 4% by weight based on the washcoat catalyst.

(Example 2)-Start of the autothermal reforming apparatus

In the present embodiment, a palladium-washed metal mesh catalyst layer (4 cm in diameter, 2 cm in height, about 25 cc in volume) was laminated on the support 12 in a self-starting autothermal reforming reactor made of stainless steel with an inner diameter of 5 cm. The space between the catalyst layer 11 filled with the washcoat metal mesh catalyst and the self-starting autothermal reforming reactor wall was filled with a high temperature insulation material 13 (0.5 cm thick) to reduce heat loss.

The autothermal reforming reactor configured as above did not use an external furnace.

When the reactor chain oxygen and steam are injected into the reactor while maintaining the flow rate (oxygen / methane = 0.5, space velocity 36,000hr- ¹ ) at 2.5L / min and 0.205 mol / min (steam / carbon ratio = 1.0), the catalyst bed shear The negative temperature (T2 in FIG. 2A) is increased to 600 ° C, and the rear end temperature (T3 in FIG. 2A) is increased to 250 ° C. At this time, when methane is injected at 5 L / min, T2 is rapidly increased and T3 is gradually raised.

At this time, when the electric heater 10 is turned off, it can be seen in FIG. 3 that T2 gradually decreases and is constantly maintained at a temperature lower than T3 and the autothermal reforming reaction is started.

In addition, T2 and T3 change when the flow rate of the reaction gas, steam / carbon, and oxygen / carbon ratio are gradually changed after the reaction is started, and the result of the reaction (composition of each component, H ₂ / CO ratio) is changed. It could be confirmed (FIGS. 4A and 4B). Increasing the oxygen / methane ratio changes partially from stoichiometric to complete oxidation, increasing the temperature inside the reactor and increasing the methane conversion.

The reaction product gas was analyzed by gas chromatograph to confirm that the methane conversion rate was 90% and the H ₂ / CO ratio was 2 to 3 depending on the operating conditions (FIGS. 5A and 5B).

The change in the flow rate of the reaction gas and the ratio of oxygen / carbon was found to have the greatest effect on the methane conversion rate, and the ratio of steam / methane to the hydrogen generation amount and H ₂ / CO (FIGS. 6A and 6B).

When methane or natural gas is injected together with oxygen, combustion takes place at the introduction part of the reactor, which promotes the consumption of oxygen, which may limit the reaction such as partial oxidation in the catalyst layer. It is better to inject it when it is reached.

If T3 is lower than this zone, the reaction will not start if methane or hydrocarbons are injected, and if the heater is turned off in this state, the T1, T2, and T3 temperatures will all go down together, preventing operation.

Methane Conversion Rate (%) = {Outlet Gas (CO + CO ₂ ) Flow Rate} × 100 / {Outlet Gas (CH ₄ + CO + CO ₂ ) Flow Rate}

H ₂ + CO (%) = {outlet gas (H ₂ + CO) flow rate} × 100 / {outlet gas (H ₂ + CO + CO ₂ ) flow rate}

H ₂ / CO = {outlet gas H ₂ flow rate} / {outlet gas CO flow rate}

(Example 3)-H ₂ / CO ratio change according to the feed steam and oxygen ratio

The methane conversion, T2, T3, H ₂ + CO selectivity, and H ₂ / CO values according to steam / carbon ratio at each space velocity are shown in Table 2.

In addition, if the steam / carbon ratio is the same, but the space velocity is increased by increasing the flow rate, the methane conversion rate increases, the composition of hydrogen gas and CO ₂ increases, and the CO decreases. This may be due to the water gas shift reaction (WGS) and Le Chatelier's law (when equilibrium is broken by some external stimulus, the system changes in a way that minimizes the effects of the stimulus). .

CO + H ₂ O → CO ₂ + H ₂

Increasing the space velocity increased the methane conversion rate, and increasing the steam / carbon ratio increased H ₂ generation to increase H ₂ / CO value, while increasing oxygen / carbon increased methane oxidation to reduce hydrogen generation. Thus reducing the H ₂ / CO value. In addition, the methane conversion rate is closely related to the catalyst performance and the reaction temperature. Thus, the careful preparation of the catalyst and the injection of the reactant gas after preheating can have a great effect.

Figures 7a to 7h shows a surface photograph after the reaction of the various catalysts used in the examples or comparative examples of the present invention, Figure 7a is a photograph of the present invention Pd / Al ₂ O ₃ catalyst after the reaction, Figure 7b is a reaction Comparative Example Pd-Ce / Al ₂ O ₃ catalyst photograph after the reaction, FIG. 7C is a comparative example Pd-Ba / Al ₂ O ₃ catalyst photograph after the reaction, and FIG. 7D shows comparative example Pd-Sr / Al ₂ O ₃ after the reaction. A photograph of the catalyst, 7e is a photograph of the comparative example Pd-Ba-Ce / Al ₂ O ₃ catalyst after the reaction, Figure 7f is a photograph of the comparative example Pd-Ba-Sr / Al ₂ O ₃ catalyst after the reaction, Figure 7g is after the reaction Comparative Example Pd-Sr-Ce / Al ₂ O ₃ Catalyst Photograph, FIG. 7H is a Comparative Example Pd-Sr-Ce-Ba / Al ₂ O ₃ Catalyst Photograph after Reaction.

As shown, there is no case in which one auxiliary component is included with Pd (FIGS. 7B, 7C and 7D), but the auxiliary component is contained in two or more combinations with Pd (FIGS. 7E and 7D). 7f and 7g), it can be seen that aggregation of particles has occurred. This can lead to a decrease in the active site by sintering or sintering, which is an important drawback directly linked to the activity.

In addition, even when no aggregation phenomenon was observed (FIGS. 7B, 7C and 7D), as shown in FIG. 1, the reactivity was remarkably decreased (FIG. 7C), or the H ₂ / CO ratio was too high (FIG. 7B and FIG. 7). 7d).

In addition, even in the case of a four-component system (Fig. 7h) a slight whisker carbon deposition is also observed, even though the catalyst proposed in the present invention of Figure 7a is a single component shows that it is remarkably superior in activity or physical shape change after the reaction, etc. Giving.

In the case of the space velocity 144,000 hr ^-1 carried out in this embodiment, a methane flow rate of 20 L / min is converted into a treatment flow rate of 1.2 Nm ³ / hr, which is required to produce 0.1 barrel / day of synthetic oil through the Fischer-Tropsch process. It is scale.

Table 2. Autothermal Reforming Activity According to Reaction Conditions [catalyst volume = 25 cm ³ ]

The present invention is not limited to the above-described specific preferred embodiments, and various modifications can be made by any person having ordinary skill in the art without departing from the gist of the present invention claimed in the claims. Of course, such changes will fall within the scope of the claims.

1 is a graph comparing the activity of the catalysts used for the present invention,

Figure 2a is an autothermal reforming reactor used to confirm the activity of the catalysts for the present invention,

Figure 2b is a structural diagram of a mesh type catalyst layer mounted on the autothermal reforming reactor used to confirm the activity of the catalysts for the present invention,

3 is a graph showing the start-up trend of the reactor using the electric heater using the catalyst of the present invention,

Figure 4a is a graph showing the temperature profile (0.5 <steam / C <1, 0.5 <O ₂ / C <0.67) in the operation of the autothermal reformer using the catalyst of the present invention,

Figure 4b is a graph showing the temperature profile (steam / C = 1 or 0.6, O ₂ / C = 0.5) in the autothermal reformer operation using the catalyst of the present invention,

Figure 5a is a graph showing the carbon conversion rate, H ₂ + CO fraction and H ₂ / CO ratio profile (0.5 <steam / C <1, 0.5 <O ₂ / C <0.67) in the autothermal reformer operation using the catalyst of the present invention ego,

Figure 5b is a graph showing the carbon conversion rate, H ₂ + CO fraction and H ₂ / CO ratio profile (steam / C = 1 or 0.6, O ₂ / C = 0.5) in the operation of the autothermal reformer using the catalyst of the present invention,

Figure 6a is a graph showing the transition profile (0.5 <steam / C <1, 0.5 <O ₂ / C <0.67) of the reactants and products in the operation of the autothermal reformer using the catalyst of the present invention,

Figure 6b is a graph showing the transition profile (steam / C = 1 or 0.6, O ₂ / C = 0.5) of the reactants and products in the operation of the autothermal reformer using the catalyst of the present invention,

7A to 7H are surface photographs after the reaction of the catalysts used according to the examples or comparative examples of the present invention.

<Description of the symbols for the main parts of the drawings>

(10): Electric Heater (EH)

(11): washcoat metal mesh catalyst layer

(12): metal mesh support

(13): high temperature insulation

(14): self-starting autothermal reforming reactor case

(T): thermocouple

Claims (10)

In the catalyst for methane autothermal reforming for the production of Fischer-Tropsch liquefaction process synthesis gas (H ₂ / CO ≒ 2), Alumina carrier having a specific surface area of greater than 100 m ² / g; A methane autothermal reforming catalyst used in a synthesis gas manufacturing process for the Fischer-Tropsch liquefaction process, which is composed of 2 to 4 wt% of palladium relative to the total weight of the carrier and the catalyst. The method of claim 1, The alumina carrier is a methane autothermal reforming catalyst used in the synthesis gas manufacturing process for Fischer-Tropsch liquefaction process, characterized in that gamma alumina (γ-alumina). The method of claim 1, The firing conditions are methane autothermal reforming catalyst used in the synthesis gas manufacturing process for Fischer-Tropsch liquefaction process, characterized in that carried out in an air atmosphere at 650 ~ 900 ℃. Electric heater (10) as a starting device in the inner front end of the autothermal reforming reactor case (14) insulated with a high temperature insulating material (13) for the production of Fischer-Tropsch liquefaction process synthesis gas (H ₂ / CO ≒ 2) And a thermocouple (T1) mounted at the rear end of the electric heater (10) and installed at the front end of the electric heater; A thermocouple (T 2) between the electric heater and the washcoat catalyst layer; In the catalyst layer structure used in the autothermal reforming reactor further comprises a thermocouple (T3) installed on the rear end of the washcoat mesh type catalyst layer, The catalyst layer is provided with at least two support members 12 which are bent upward in the autothermal reformer case 14 at predetermined intervals in the bottom space of the electric heater 10, and the supporters 1 to 1 above. Fischer-Tropsch liquefaction process for syngas production process characterized in that the palladium-carrying catalyst according to any one of the three characterized in that the mesh-type catalyst layer (11) consisting of laminating a plurality of mesh-shaped metal plate wash Mesh type catalyst layer using methane autothermal reforming catalyst used. The method of claim 4, wherein The mesh metal plate constituting the mesh catalyst layer 11 is used in the synthesis gas manufacturing process for the Fischer-Tropsch liquefaction process, wherein the catalyst on which the palladium is loaded is 15 to 20 wt% of the total amount of the mesh metal plate. Mesh type catalyst layer using a methane autothermal reforming catalyst. The method of claim 4, wherein Fischer-Tropsch liquefaction process synthesis gas manufacturing process, characterized in that the mesh-like metal plate constituting the mesh catalyst layer 11 is composed of an alloy plate of 50 ~ 100 micrometers thick alloy plate does not deteriorate around 1000 ℃ Mesh type catalyst layer using methane autothermal reforming catalyst used in. The method of claim 4, wherein The mesh-type metal plate area opening% constituting the mesh-type catalyst layer 11 is 60-70%, and the mesh-type using the methane autothermal reforming catalyst used in the synthesis gas manufacturing process for the Fischer-Tropsch liquefaction process is used. Catalyst bed. The method of claim 4, wherein Fischer-Tropsch liquefaction process, characterized in that the mesh metal plate constituting the mesh catalyst layer 11 is laminated so that the mesh holes of the neighboring mesh metal plate is arranged to have an irregular flow path without forming a vertical flow path Mesh type catalyst layer using methane autothermal reforming catalyst used in syngas production process. Electric heater (10) as a starting device in the inner front end of the autothermal reforming reactor case (14) insulated with a high temperature insulating material (13) for the production of Fischer-Tropsch liquefaction process synthesis gas (H ₂ / CO ≒ 2) And a thermocouple (T1) mounted at the rear end of the electric heater (10) and installed at the front end of the electric heater; A thermocouple (T 2) between the electric heater and the washcoat catalyst layer; The autothermal reforming reactor further comprises a thermocouple (T3) installed at the rear end of the washcoat mesh type catalyst layer, Mixing one of oxygen or air and one of steam or methane or natural gas supplied in a separate feed line; Heating a monolithic type electric heater for starting; Afterwards, the reaction mixture in which one of oxygen or air, steam and one of methane or natural gas is mixed, and the catalyst (PdO / Al ₂ O ₃ ) supported on alumina having a specific surface area of palladium of greater than 100 m ² / g is washed. Stacking the plurality of mesh metal plates and supplying them to the filled mesh catalyst layer for catalytic partial oxidation; After the catalytic partial oxidation reaction, the catalytic partial oxidation, steam reforming reaction, and water gas transfer reaction are continued without external energy supply to produce hydrogen and carbon monoxide at the optimum ratio for the Fischer-Tropsch liquefaction reaction, Methane or natural gas supplied to the catalytic partial oxidation reaction Fischer-Tropsch liquefaction process, characterized in that the configuration is configured to be injected when the temperature of the thermocouple (T3) at the rear end of the mesh catalyst layer reaches the 200 ℃ ~ 250 ℃ region Fischer-Tropsch synthesis gas production method using a methane autothermal reforming catalyst used in the gas production process. The method of claim 9, The step of catalytic partial oxidation is Fischer-Tropsch liquefaction process synthesis gas production characterized in that for controlling the catalytic partial oxidation reaction by controlling the amount of catalyst by controlling the number of layers of the mesh metal plate laminated on the mesh type catalyst layer 11 Fischer-Tropsch syngas production method using a methane autothermal reforming catalyst used in the process.

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