KR101166074B1 - Manganese based Catalysts for Carbon dioxide reforming of Methane, Preparing method thereof, and Preparing method of Syngas using the same - Google Patents

Abstract

The present invention relates to a manganese catalyst for carbon dioxide reforming of methane, a method for preparing the same, and a method for preparing a synthesis gas using the same. More specifically, one type of zirconium and lanthanum together with a platinum group element and manganese may be used at a specific ratio. Or it relates to a catalyst supported on an alumina carrier, and also to a method for producing the catalyst and a method for producing a synthesis gas containing carbon monoxide and hydrogen by using the catalyst for the carbon dioxide reforming reaction of methane. The manganese catalyst of the present invention is excellent in stability and activity due to excellent carbon deposition phenomenon even in a long time reaction, and when applied to the synthesis gas manufacturing process can produce a synthesis gas having a high content of carbon monoxide, it has a great effect on global warming It can make use of the carbon dioxide that is mad.

Description

Manganese based Catalysts for Carbon dioxide reforming of Methane, Preparing method etc, and Preparing method of Syngas using the same}

The present invention relates to a manganese catalyst for carbon dioxide reforming reaction of methane and a method for producing the same, and also to a method for preparing a synthesis gas containing hydrogen and carbon monoxide using the manganese catalyst. Since the manganese catalyst of the present invention has excellent stability and activity, and can be produced in a synthesis gas having a high content of carbon monoxide when applied to the synthesis gas production process, it is possible to resource the carbon dioxide which has a great influence on global warming.

As the cause of extreme weather caused by the instability of the atmospheric layer is recently revealed by the effects of greenhouse gases such as carbon dioxide, methane, sulfur compounds and fluorine compounds, which are triggering global warming, As these are classified as emission control substances, R & D on GHG reduction technology is actively progressing. In particular, global attention has been focused on reducing carbon dioxide emissions or fixing the emitted carbon dioxide physically and chemically. In the past, technology development was conducted to reduce CO2 emissions, but domestic companies have the highest energy efficiency in the world, so they have limited capacity to reduce GHG emissions. It is feared that the rise will face productivity problems and plant relocation to overseas markets. Accordingly, research on ways to reduce carbon dioxide emissions and to recycle carbon dioxide emissions is ongoing.

Syngas is a mixed gas composed mainly of hydrogen and carbon monoxide, and is manufactured by coal gasification, steam reforming of hydrocarbons using natural gas, or partial oxidation reforming with oxygen. Has been. The coal gasification method requires an expensive coal gasification heater and a large-scale plant. In the steam reforming of hydrocarbons and the partial oxidation reforming of hydrocarbons, as a reforming gas, carbon dioxide, oxygen, steam, or a mixture thereof is used. There is a need for a reforming catalyst having high heat resistance applicable to endothermic reaction at high temperature (700-1200 ° C). Currently, nickel-based catalysts, which are widely known as catalysts for reforming reactions, have high activity and are used commercially, but have a large problem in the durability of catalysts due to the rapid generation of coke. Recently, a method for producing syngas through reforming of methane using carbon dioxide has been disclosed. If such a technique can be applied on a commercial scale, it is expected to be able to resource the carbon dioxide emitted.

In the method of producing syngas, the reforming reaction of methane using carbon dioxide can produce syngas (H ₂ : CO = 1: 1) having a much higher carbon monoxide content than other reforming methods. It can be used as a raw material for Ropsch synthesis to produce high value added chemicals such as oxoalcohol, dimethyl ether, polycarbonate and acetic acid. The carbon dioxide reforming reaction of methane proceeds as in Scheme 1 below.

[Reaction Scheme 1]

The reaction is a very strong endothermic reaction, the equilibrium conversion, which is the theoretical maximum conversion at a given temperature, increases with increasing temperature, and the reaction occurs at a temperature above 650 ° C., and usually proceeds at a high temperature of 800 ° C. or higher. This reaction is characterized by a high carbon-to-hydrogen ratio of the reactor, thermodynamically easy to form carbon, showing excellent activity at a lower temperature and the development of a catalyst that is resistant to coking and deactivation by sintering.

Looking at the catalyst for the reforming reaction of methane using the existing carbon dioxide, [Chem. Lett., 1953 (1992)] shows a Ni-MgO catalyst, and Korean Patent No. 10-0395095 discloses a nickel-manganese-alumina catalyst. In addition, [J. Chem. Soc., Chem. Commun., 71 (1995)] and Inter. J. Hydro. Ene. 28 (2003), 1045 discloses a catalyst in which nickel metal is supported on a lanthanum oxide (La ₂ O ₃ ) carrier, and in Korean Patent No. 10-0482646, a nickel metal is supported on a carrier surface composed of cerium zirconium oxide. Korean Patent No. 10-0912725 discloses a catalyst in which nickel metal is supported on a tungsten carbide (WC) carrier. Korean Patent No. 10-0336968 proposes a nickel-based reforming catalyst in which alkali metals, alkaline earth metals, and the like are supported as a promoter on zirconia carriers modified with alkaline earth metals and group IIIB metals. In addition, Korean Patent No. 10-0110984 discloses a catalyst in which nickel is supported on a silicon-containing carrier such as zeolite, silica, silicate, silica-alumina together with an alkali metal and an alkaline earth metal promoter, and in Korean Patent No. 10-0264160 A nickel catalyst supported on an alumina airgel carrier is presented. In Korean Patent No. 10-0732729, methane is a triple (mixed gas of carbon dioxide, oxygen and water vapor) reforming catalysts, and yttrium is essential to a zirconia carrier and is doped with a mixed metal containing a metal selected from lanthanide and alkaline earth metal elements. One nickel-based catalyst is disclosed.

As described above, in the reforming reaction of methane using carbon dioxide, as with steam reforming, attempts have been made to develop a high performance nickel-supported catalyst having a low cost and strong resistance to carbon deposition, but faced limitations due to the short catalyst life of nickel. Doing. Accordingly, researches on noble metal catalysts having greater resistance to carbon deposition and better activity than nickel catalysts have been actively conducted.

In US Patent No. 5068057, Pt / Al ₂ O ₃ and Pd / Al ₂ O ₃ catalysts are known, and in WO 92 / 11,199, precious metal-supported alumina catalysts such as iridium, rhodium, ruthenium, etc. It has been shown to exhibit long life. WO 2004/103555 and WO 2008/099847 disclose a catalyst having a spinel structure as a metal oxide containing copper as an essential element and having at least one element selected from nickel, cobalt and platinum group elements. However, although reforming with carbon dioxide is mentioned, the examples are limited to methanol and dimethylether steam reforming. WO 2002/081368 discloses iron or iron oxides containing Ti, Zr, V, Nb, Cr, Mo, Al, Ga, Mg, Sc, Ni, or Cu as steam reforming catalysts, There are few considerations on the reduction rate, H ₂ / CO selectivity and inhibition of carbon deposition that can occur when reducing. Korean Patent No. 10-0938779 discloses a catalyst using a complex metal oxide containing Cu-Fe or Sn-Fe, but the deactivation is insufficient. In addition, Japanese Patent Application Laid-Open No. 11-276893 discloses the reforming reaction of methane by carbon dioxide on a metal oxide catalyst using a hydrotalcite precursor using noble metals (Rh, Pd, Ru) and transition metals (Ni) as active metals. It is known. However, although the conversion rate of methane was more than 90% at 800 ° C., even though expensive precious metals were used, the conversion rate drastically decreased in the temperature range below that, and the catalyst containing 5% by weight of rhodium at 600 ° C. (methane conversion rate of about 50%) Except for the methane conversion rate of less than 30% has been reported. U. S. Patent No. 5744419 discloses on a carrier such as silica, alumina, zirconia, which is pre-coated with nickel or cobalt with alkaline earth metals in accordance with the presence of precious metals in connection with steam reforming including oxygen reforming and carbon dioxide reforming. The supported catalyst is known from U. S. Patent No. 4026823, a nickel catalyst supported on zirconia in which cobalt is added to nickel as a steam reforming catalyst for hydrocarbons.

However, the noble metal catalyst as described above has a problem in that it is difficult to apply commercially because of high manufacturing cost.

Accordingly, the inventors of the present invention have repeatedly studied the resources of carbon dioxide, which have a great influence on global warming, and have developed a manganese-based catalyst in which the active metal containing manganese is impregnated on the surface of the carrier. When applied as a catalyst of the reaction, it was found that not only the durability of the reaction for a longer time than the nickel-based catalyst, the stability and activity of the catalyst at low temperature, but also the synthesis gas having a high content of carbon monoxide can be prepared to complete the present invention. It became.

Accordingly, an object of the present invention is to provide a catalyst for carbon dioxide reforming of methane having excellent durability, stability, and activity, a method for preparing the same, and a method for preparing a synthesis gas including hydrogen and carbon monoxide using the catalyst.

The present invention is characterized by a manganese-based catalyst for carbon dioxide reforming of methane represented by the following formula (1).

[Formula 1]

X-Mn-Y / Z

In Chemical Formula 1, X is platinum, palladium, rhodium, iridium, or ruthenium, Y is zirconium or lanthanum, Z is silica or alumina as a carrier, and X is 0.1 to 10 parts by weight based on 100 parts by weight of the carrier, Manganese is 5 to 30 parts by weight, and Y is 1 to 30 parts by weight.

In addition,

Preparing a mixture in which the X component, manganese and Y component are supported on the silica or alumina carrier according to the composition ratio of Chemical Formula 1;

Drying the mixture at a temperature of 50-110 ° C. to produce a dry matter; And

Firing the dried product at a temperature of 200 to 900 ° C;

Characterized in that the manufacturing method of the manganese catalyst represented by the formula (1) comprising a.

In another aspect, the present invention is characterized by a method for producing a synthesis gas containing carbon monoxide and hydrogen by reacting a mixed gas having a volume ratio of 1: 0.5 to 2.0 of methane and carbon dioxide under the manganese catalyst.

The manganese-based catalyst for carbon dioxide reforming of methane according to the present invention has a specific ratio of the active ingredient including manganese at a specific ratio, which is superior to the existing nickel-based catalyst, and thus can maintain a high reaction activity for a long time and at low temperature. Excellent catalytic activity and stability. In addition, the carbon dioxide reforming reaction of methane to which such a catalyst is applied generates a synthesis gas having a high carbon monoxide ratio, which is a raw material for high value-added products such as oxo alcohol, dimethyl ether, polycarbonate, and acetic acid. Active countermeasures are available for climate change conventions.

1 is a graph showing an XRD analysis of the catalyst prepared in Example 6.
Figure 2 shows the conversion rate of methane and carbon dioxide over the reaction time of the carbon dioxide reforming reaction of methane using the catalyst prepared in Example 5.
Figure 3 shows the conversion of methane and carbon dioxide over the reaction time of the carbon dioxide reforming reaction of methane using the catalyst prepared in Example 6.
Figure 4 shows the conversion of methane and carbon dioxide over the reaction time of the carbon dioxide reforming reaction of methane using the catalyst prepared in Comparative Example 3.

Hereinafter, the present invention will be described in more detail.

The present invention relates to a catalyst for carbon dioxide reforming of methane represented by the following formula (1) using manganese as a main catalyst.

[Formula 1]

X-Mn-Y / Z

In Formula 1, X is platinum, palladium, rhodium, iridium, or ruthenium, Y is zirconium or lanthanum, and Z is silica or alumina as a carrier.

It is generally known that other transition metals such as cobalt, nickel, zirconium, and the like are used as active ingredients in the catalyst used in the reforming reaction of methane and carbon dioxide, and alumina and silica are used as carrier components. However, even if the catalyst is used the same components, the activity is known to appear completely different depending on the mixing ratio of each component, that is, the relative ratio. Accordingly, a three-phase manganese catalyst in which an active metal is dispersed in a carrier was developed by using manganese as the main catalyst and selectively using a transition metal previously proposed as a cocatalyst, and adjusting its content at an optimum ratio.

X is a platinum group element platinum (Pt), palladium (Pd), rhodium (Rh), iridium (Ir), or ruthenium (Ru), Z is a silica (SiO ₂ ) or alumina (Al ₂ O ₃ ) carrier 100 It is good to use 0.1-10 weight part with respect to a weight part, Preferably it is 0.2-5 weight part. When the content of X is less than 0.1 part by weight, the effect of increasing the activity of the X component may not appear, and even if it exceeds 10 parts by weight, the benefits of the increase according to the increase may be insignificant, and the economy may be inferior. It is desirable to.

The manganese (Mn) is used as the main catalyst, it is preferable to use 5 to 30 parts by weight, preferably 10 to 20 parts by weight with respect to 100 parts by weight of the carrier. When the content of manganese is less than 5 parts by weight, the conversion of methane and carbon dioxide may be lowered. If it exceeds 30 parts by weight, rapid carbon deposition may occur, resulting in deactivation of the catalyst, thereby reducing the life of the catalyst.

The Y is selected from zirconium (Zr) or lanthanum (La), it is preferable to use in the range of 1 to 30 parts by weight, preferably 5 to 20 parts by weight with respect to 100 parts by weight of the carrier, the content of Y is less than 1% by weight If the activity increase effect may not appear, the activity of the catalyst may be rather deteriorated when it is mixed in excess of 30 parts by weight.

The present invention also relates to a method for preparing the manganese catalyst represented by Chemical Formula 1 by supporting the X component, manganese and Y component on a silica or alumina carrier, and drying and calcining.

In the step of preparing a mixture in which the X component, manganese and Y component are supported on the carrier, the supporting method is not particularly limited. For example, various kinds of impregnation methods such as heating impregnation method, room temperature impregnation method, vacuum impregnation method, atmospheric impregnation method, evaporation drying method, pore filling method, incipient wetness method, and immersion method, spraying method, or ion exchange method, etc. It can be adopted. The X component, manganese and Y component can be supported on the carrier by using the precursor compound. Specifically, as the platinum precursor, PtCl ₄ , H ₂ PtCl ₆ , Pt (NH ₃ ) ₄ Cl ₂ , (NH ₄ ) ₂ PtCl ₂ , H ₂ PtBr ₆ , NH ₄ [Pt (C ₂ H ₄ ) Cl ₃ ], At least one selected from Pt (NH ₃ ) ₄ (OH) ₂ and Pt (NH ₃ ) ₂ (NO ₂ ) ₂ includes (NH ₄ ) ₂ PdCl ₆ , (NH ₄ ) ₂ PdCl ₄ , Pd as a palladium precursor. (NH ₃ ) ₄ Cl ₂ , PdCl ₂ And at least one selected from Pd (NO ₃ ) ₂ , and at least one selected from Na ₃ RhCl ₆ , (NH ₄ ) ₂ RhCl ₆ , Rh (NH ₃ ) ₅ Cl _3, and RhCl ₃ as a rhodium precursor. As a precursor, (NH ₄ ) ₂ IrCl ₆ , IrCl ₃ , H ₂ IrCl ₆ , or a mixture thereof may be used. Also, ruthenium precursors include RuCl ₃ nH ₂ O, Ru (NO). (NO ₃ ) ₃ , Ru (NO ₃ ) ₃ , Ru ₂ (OH) ₂ Cl ₄ 7NH ₃ 3H ₂ O and K ₂ (RuCl ₅ (H ₂ O)) may be used one or more selected, preferably from the viewpoint of handling, Ru (NO) · (NO ₃ ) ₃ or Ru (NO ₃ ) ₃ It is preferable to use.

Manganese, the main catalyst, may use at least one of Mn (NO ₃ ) ₂ ㆍ nH ₂ O, Mn (OH) ₂ , MnCl ₂ , MnS, Mn ₂ (SO ₄ ) ₃ , MnF ₂ and MnCO ₃ as precursors. Preferably, Mn (NO ₃ ) ₂ nH ₂ O is used. In addition, as a zirconium precursor, ZrCl ₄ , ZrCl ₂ , ZrO (NO ₃ ) ₂ ㆍ H ₂ O, ZrO ₂ , Zr (OH) ₄ , ZrClOH, Zr (NO ₃ ) ₄ ㆍ 5H ₂ O, ZrOCl ₂ ㆍ 8H ₂ O and Zr (SO ₄ ) ₂ and more than, and, preferably, it is better to use a Zr (NO _{3) 4} and 5H ₂ O or ZrOCl ₂ 8H ₂ O and from the viewpoint of handling. In addition, as the lanthanum precursor, LaCl _3, LaCl ₃ .7H ₂ O, La (OH) _3, La (NO ₃ ) _3, La (NO ₃ ) ₃ ㆍ 6H ₂ O, La ₂ O _{3 ,} La ₂ (SO ₄ ) may be used at least one member selected from among ₃ · 8H ₂ O and LaCl ₃ • 6H ₂ O, it is preferred to use a nitrate.

In supporting the X component, the manganese and the Y component on the carrier by using the precursor compound, it is more preferable to individually support each component than to dissolve the entire precursor compound for each component in water. This is because the active component can be more evenly dispersed on the surface of the carrier by supporting the components, and the mutual synergistic effect can effectively prevent carbon deposition, which is the main cause of catalyst deactivation.

The drying step of the mixture is preferably carried out for 5 to 24 hours at 50 ~ 110 ℃, if the drying temperature is less than 50 ℃ is disadvantageous to increase the manufacturing time by lowering the evaporation rate of the aqueous solution, too high if it exceeds 110 ℃ It is desirable to maintain this range because there may be a problem of increased pore size of the catalyst which causes catalyst deactivation due to rapid evaporation of aqueous solution.

Moreover, it is preferable to perform baking of a dried product for 5 to 24 hours at 200-900 degreeC. If the calcination temperature is less than 200 ° C, the physical properties of the catalyst do not change and only the dried state is maintained, so that it is difficult to form a chemical bond as a catalyst.If the firing temperature is higher than 900 ° C, the degree of oxidation of the catalyst is large and the phase decomposition of the catalyst starts to occur. Therefore, it is preferable to maintain the above range.

In general, the reforming catalyst of methane and carbon dioxide performs a function as a catalyst through an appropriate pretreatment process, that is, a reduction reaction, before the reaction. However, the catalyst of the present invention is uniformly distributed on the surface of the carrier manganese and cocatalyst X component, Y component, thereby preventing carbon deposition, which is the main cause of deactivation due to the mutual synergistic effect, without the reduction process It stably sustains the activity of the catalyst.

The present invention also relates to a method for preparing a synthesis gas containing carbon monoxide and hydrogen by reforming a mixed gas having a volume ratio of methane and carbon dioxide 1: 0.5 to 2.0 under the manganese catalyst.

The reactor for the reforming reaction is not particularly limited as long as it is generally used in the art, and specifically, a fixed bed reactor, a fluidized bed reactor, or a reactor in the form of a liquid slurry may be used. The volume ratio of the reactant methane and carbon dioxide is preferably 1: 0.5 to 2.0. If the volume ratio is outside the above range, it is preferable to maintain the above range because it becomes an inefficient reaction in which only one reactant has a high conversion rate. The mixed gas may include inert gases nitrogen, helium, argon, etc. in addition to the reactants methane and carbon dioxide.

The reaction conditions were maintained at a reaction temperature of 650 to 850 ° C, a reaction pressure of 0.01 to 1 MPa, and a space velocity of 500 to 100,000 mL / g _cat ㆍ hr, preferably 5,000 to 50,000 mL / g _cat · hr. It is desirable to. The reason why the reaction temperature is lower than that of the conventional nickel-based reforming catalyst is to prevent the carbonization of the catalyst and the change of the properties of the catalyst due to the high temperature reaction so as to maintain the catalyst activity stably. If the reaction temperature is less than 650 ° C., the reaction rate may not be sufficient and conversion may hardly occur. If the reaction temperature is higher than 850 ° C., carbonization of the catalyst may be started to promote deactivation. In addition, when the reaction pressure is increased, the activity of the catalyst is maintained stably, but it is not a largely applied variable. If it is out of the reaction pressure range, it is not preferable in terms of economics such as an increase in reactor installation cost. In addition, if the space velocity of the mixed gas is too low, there may be a problem that the productivity is too low, on the contrary, if too high, the contact time between the reactants and the catalyst is shortened there may be a problem that promotes the deactivation of the catalyst.

As described above, the manganese catalyst of the present invention is evenly dispersed in the active metal on the surface of the carrier, and can be effectively applied to the reforming reaction of methane and carbon dioxide without the need for a reduction process. In addition, since the synthesis gas having a high ratio of carbon monoxide can be produced at a high conversion rate compared with the conventional catalyst for reforming methane and carbon dioxide, it is possible to resource the carbon dioxide for converting carbon dioxide into a raw material of high value added chemicals.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited by the following Examples.

[Example]

Example 1

ZrOCl ₂ · 8H ₂ O, a zirconium precursor, was weighed and dissolved in water, mixed with SiO ₂ as a carrier, distilled under reduced pressure at 60 ° C. to evaporate water, and dried at 80 ° C. for 5 hours. . Next, manganese and ruthenium were sequentially supported using Mn (NO ₃ ) ₂ .nH ₂ O as a manganese precursor and Ru (NO) · (NO ₃ ) ₃ as a ruthenium precursor in the same manner as described above, and for 5 hours. After drying, the mixture was calcined at 400 ° C. for 6 hours to prepare a Ru—Mn—Zr / SiO ₂ catalyst. Specific composition ratios are shown in Table 1 below.

Examples 2-14

In the same manner as in Example 1, to prepare a Ru-Mn-Y / Z catalyst in the component and composition ratio of Table 1 below. When lanthanum was selected as the Y component, La (NO ₃ ) ₃ ㆍ 6H ₂ O was used as the precursor, and Al ₂ O ₃ was used as the Z component. or SiO ₂ was used.

Examples 15-18

In the same manner as in Example 1, to prepare a X-Mn-Y / Z catalyst in the component and composition ratio of Table 1. Platinum (Pt), palladium (Pd), rhodium (Rh) and iridium (Ir) were selected as X components, and H ₂ PtCl ₆ , (NH ₄ ) ₂ PdCl ₆ , (NH ₄ ) ₂ RhCl ₆ as precursors. And H ₂ IrCl ₆ were used, respectively.

Comparative Examples 1 and 2

In the same manner as in Example 1, except for the components and composition ratios of Table 1 Mn / SiO ₂ and Ru / SiO ₂ Catalyst.

Comparative Example 3

In the same manner as in Example 1, to prepare a Ru-Ni-Zr / SiO ₂ catalyst in the component and composition ratio of Table 1 below. Ni (NO ₃ ) ₂ .6H ₂ O was used as the nickel precursor.

  Catalytic activity evaluation

In order to compare the performance of the catalysts prepared in Examples 1 to 18 and Comparative Examples 1 to 3, the reforming reaction of methane and carbon dioxide was carried out in the following manner, and the results are shown in Table 1 below. First, the prepared catalyst was charged 0.2 g into the reactor in the size of 60 ~ 80 mesh. The reactor was a fixed bed tubular reactor with an external heating system, made of stainless steel 500 mm long and 9.25 mm internal. A mixed gas containing a volume ratio of methane and carbon dioxide of 1: 1 and 20% by volume of nitrogen was supplied to the reactor at a flow rate of 20,000 mL / g _cat · hr. The reforming reaction was carried out at a reaction temperature of 680 ~ 850 ℃ in atmospheric pressure. The gas released after the reaction was analyzed by the thermal conductivity detector of the on-line gas chromatography system.

division Ingredients and Composition Ratio reaction
Temperature
(℃) CH ₄
Conversion rate
(%) CO ₂
Conversion rate
(%) CO / H ₂
volume
ratio X Mn (Ni) Y Carrier Z
(100 parts by weight) ingredient Weight portion Weight portion ingredient Weight portion Example 1 Ru 0.5 10 Zr 5 SiO ₂ 680 24 39 1.6 Example 2 Ru 0.5 15 Zr 5 SiO ₂ 680 24 44 1.8 Example 3 Ru 0.5 20 Zr 5 SiO ₂ 680 27 48 1.3 Example 4 Ru 0.5 30 Zr 5 SiO ₂ 700 30 50 1.5 Example 5 Ru 1.0 10 Zr 5 SiO ₂ 700 46 59 1.3 Example 6 Ru 1.0 15 Zr 5 SiO ₂ 700 47 63 1.3 Example 7 Ru 1.0 20 Zr 5 SiO ₂ 700 41 56 1.4 Example 8 Ru 1.5 20 Zr 5 SiO ₂ 700 40 55 1.4 Example 9 Ru 0.5 10 La 5 Al ₂ O ₃ 700 36 54 1.4 Example 10 Ru 1.0 20 La 5 Al ₂ O ₃ 700 36 57 1.5 Example 11 Ru 1.5 20 La 5 Al ₂ O ₃ 700 42 57 1.4 Example 12 Ru 0.3 20 La 5 SiO ₂ 850 44 63 2.0 Example 13 Ru 0.5 20 La 9 SiO ₂ 850 40 75 1.5 Example 14 Ru 1.0 20 La 15 SiO ₂ 850 36 58 1.5 Example 15 Pt 0.1 10 Zr 5 SiO ₂ 750 18 34 1.9 Example 16 Pd 0.1 10 Zr 5 SiO ₂ 750 21 38 1.8 Example 17 Rh 0.2 10 Zr 5 SiO ₂ 750 20 36 1.8 Example 18 Ir 0.5 15 Zr 5 SiO ₂ 750 26 47 1.8 Comparative Example 1 - - 15 - - SiO ₂ 700 12 24 2.0 Comparative Example 2 Ru 1.0 - - - SiO ₂ 700 13 25 1.9 Comparative Example 3 Ru 0.5 (9) Zr 5 SiO ₂ 750 45 66 1.5

As shown in Table 1 above, when using the catalysts of Examples 1 to 8 prepared in the present invention, CO ₂ The conversion rate of and CH ₄ is 39 ~ 63%, 24 ~ 47%, respectively, it can be seen that the carbon monoxide was produced in more than 1.3 volume ratio of hydrogen. In addition, the catalysts of Examples 9 to 14 in which zirconium was replaced with lanthanum also showed similar conversion rates as in Examples 5 to 8, and high conversions were obtained when the reaction temperature was high (850 ° C.) as in Examples 12 to 14. It can be seen that. In the case of using platinum, palladium, rhodium and iridium as X components as in Examples 15 to 18, the conversion rate of CO ₂ and CH ₄ was slightly reduced compared to the case of using ruthenium under a certain composition ratio. The results show that it acts as a promoter in manganese catalysts.

In the case of the Mn / SiO ₂ catalyst of Comparative Example 1 using only manganese as the main catalyst and the Ru / SiO ₂ catalyst of Comparative Example 2 using only ruthenium as the promoter, CO ₂ And the conversion of CH ₄ is shown to 24 to 25%, 12 to 13%, respectively, each catalyst shows a degree of conversion, but the results were significantly lower than the conversion of Examples 1 to 14 combining them. This is because the three-phase manganese catalyst of the present invention exhibits a synergistic effect due to the bonding between the active metals by containing a specific component in an appropriate composition ratio. In the Ru-Ni-Zr / SiO ₂ catalyst of Comparative Example 3 in which manganese was replaced with nickel, the conversion of CO ₂ and CH ₄ was the highest, but as shown in FIG. 4, a sudden carbon deposition phenomenon occurred within 20 hours of the reforming reaction. This caused a sharp decrease in conversion rates.

2 to 3 show the conversion of methane and carbon dioxide over time using the catalysts of Example 5 and Example 6, respectively. Since the conversion rate of methane and carbon dioxide is maintained at a constant difference from the beginning of the reaction after about 40 hours, it can be confirmed that stable activity is maintained for a long time. As such, the high carbon dioxide conversion rate of about 60% even at a low temperature around 700 ℃, and the long-term stable activity is believed to be due to the synergistic effect rather than the characteristics of each component.

After all, when the manganese-based catalyst according to the present invention is applied to the carbon dioxide reforming reaction of methane, it is possible to produce a synthesis gas having a high carbon monoxide ratio from carbon dioxide, it can be confirmed that the resource conversion to convert carbon dioxide into a raw material of high value-added chemical products. there was.

Claims (5)

Manganese catalyst for carbon dioxide reforming of methane represented by Formula 1 below:
[Formula 1]
X-Mn-Y / Z
In Formula 1, X is platinum, palladium, rhodium, iridium or ruthenium, Y is zirconium or lanthanum, Z is silica or alumina as a carrier, X is 0.1 to 10 parts by weight, and manganese based on 100 parts by weight of the carrier. Is 5 to 30 parts by weight, and Y is 1 to 30 parts by weight.
delete A method of preparing a synthesis gas containing carbon monoxide and hydrogen by reacting a mixed gas having a volume ratio of 1: 0.5 to 2.0 under a manganese catalyst of claim 1.
According to claim 3, wherein the reaction is a synthesis gas containing carbon monoxide and hydrogen, characterized in that carried out at a reaction temperature of 650 ~ 850 ℃, reaction pressure 0.01 ~ 1 MPa and space velocity 500 ~ 100,000 mL / g _cat ㆍ hr How to make.
The method of claim 3, wherein the reaction is performed in a fixed bed, fluidized bed, or slurry reactor.

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