KR101437072B1

KR101437072B1 - Catalyst for efficient co2 conversion and method for preparing thereof

Info

Publication number: KR101437072B1
Application number: KR1020110142444A
Authority: KR
Inventors: 송상훈; 장태선; 김범식
Original assignee: 한국화학연구원
Priority date: 2011-12-26
Filing date: 2011-12-26
Publication date: 2014-09-03
Also published as: CN103170335A; KR20130074393A

Abstract

The present invention relates to a cobalt-based catalyst for reforming hydrocarbons such as methane and carbon dioxide, and a catalyst for maximizing the stability of the catalyst while maintaining the activation at a high space velocity. More particularly, 2], and a method for converting a large amount of carbon dioxide into syngas by using the same.
[Chemical Formula 1]
(a) Co / (d) Z
Wherein Z represents a spinel type carrier comprising A, B and O, and A represents a spinel type carrier comprising 1, 2, or 3 selected from the group consisting of Mg, Cr, Mn, Fe, Co, Ni, Cu, Zn, B represents at least one kind selected from the group consisting of Al, Ga, In, Ti, V, Cr, Mn, Fe, Ni and Co; a represents the weight part of Co; d represents spinel -Shaped carrier Z, and a represents 1 to 100 parts by weight based on 100 parts by weight of the spinel-like carrier d.
(2)
(a) Co- (b) X- (c) Y / (d) Z
Wherein X is Os, Pt, Pd, Rh, Ir or Ru, and Y is Zr or La. A represents at least one element selected from the group consisting of Mg, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Sn, and Z represents a spinel type carrier comprising A, B represents at least one member selected from the group consisting of Al, Ga, In, Ti, V, Cr, Mn, Fe, Ni and Co, a represents a weight part of Co, b represents a weight part of X, a represents 1 to 100 parts by weight, b represents 0 to 5.0 parts by weight based on 100 parts by weight (d = 100) of the spinel type support Z, c represents the weight part of Y, d represents the weight part of the spinel type support Z, and c represents 0 to 30 parts by weight, provided that b and c are not both 0. Preferably, b represents 0.001 to 5.0 parts by weight, and c represents 0.1 to 30 parts by weight.
In addition, the catalyst of the present invention is a catalyst for supporting a cobalt-based active material using a spinel type carrier. This catalyst maintains the activity of hydrocarbons and carbon dioxide at the same conversion rate continuously and maintains higher activity and stability than conventional catalysts. More specifically, the spinel type carrier reduces conversion loss due to side reactions and exhibits stable and high activity at a high space velocity of 100,000 ml / g _cat . Hr or more.
Index
Carbon dioxide, methane, carbon monoxide, spinel, cobalt

Description

TECHNICAL FIELD [0001] The present invention relates to an efficient carbon dioxide conversion catalyst and a method for producing the same. BACKGROUND ART < RTI ID = 0.0 >

The present invention relates to a process for producing hydrocarbons and carbon dioxide which have a great influence on global warming and a method for producing a synthesis gas containing hydrogen and carbon monoxide which serves as an intermediate for finally producing a high value added hydrocarbon compound The present invention relates to a cobalt-based reforming catalyst which is superior in activity to an existing nickel-reforming catalyst and solves inactivation of the catalyst, a process for producing the same, and a process for producing a synthesis gas containing carbon monoxide and hydrogen using the catalyst.

As the global warming causes global greenhouse gas reduction proposals to be announced, the government of the Republic of Korea has set the target of reducing greenhouse gas emissions to 30% of the 2020 emission estimate. In particular, it is inevitable that the energy-consuming and export industries, including steel, automobiles, and petrochemicals, will be hit. The problem is that the energy efficiency level of domestic companies is the best in the world, so there is limited greenhouse gas reduction capability. In addition, if the government imposes regulations on the means of reduction, it is worrisome that companies will move factories overseas or production disruptions caused by rising costs.

As an alternative to this, the present invention focuses on the use of carbon dioxide to be discharged rather than reducing carbon dioxide emissions. That is, the synthesis gas produced in the present invention contains carbon monoxide and hydrogen, and can be widely used as a synthesis raw material for various high-value chemical products such as methanol synthesis, oxo synthesis, Fischer Tropsch synthesis, and the like.

Conventional synthesis gas has been produced by a method of gasification of coal, a steam reforming method of hydrocarbons using natural gas or the like as a raw material, a partial oxidation reforming method, and the like. The coal gasification method requires expensive coal gasification heaters and a large-scale plant. In the steam reforming method of hydrocarbons and the partial oxidation reforming of hydrocarbons, the gas for reforming reaction may be a gas such as carbon dioxide, oxygen, steam, High heat resistance is required for a catalyst used at a high temperature of 700 to 1200 DEG C by an endothermic reaction. Nickel-based catalysts, widely known as catalysts for reforming reactions, have been studied extensively because of their high activity. However, the catalysts have a serious problem due to the rapid formation of coke. Due to these problems, catalyst development is urgently required, and many researchers are working on catalyst development.

Among the synthesis gas production methods, the reforming reaction of methane using carbon dioxide can produce synthesis gas (H ₂ : CO = 1: 1) having a higher carbon monoxide content than other reforming methods. Therefore, the produced syngas can be easily used in a high-value chemical production process such as oxo alcohol, dimethyl ether (DME), polycarbonate (PC), acetic acid have.

On the other hand, the carbon dioxide dry reforming reaction of methane proceeds as shown in the following reaction formula (1).

[Reaction Scheme 1]

CH ₄ + CO ₂ -> 2CO + 2H ₂ , ΔH ⁰ ₂₉₈ = + 247.3 kJ / mol

The reaction of Reaction Scheme 1 is a very strong endothermic reaction. The equilibrium conversion rate, which is the theoretical maximum conversion rate at a given temperature, increases with increasing temperature, and the reaction occurs at a temperature of 650 ° C or higher. do. This reaction is characterized by high carbon consumption of the reaction gas, which is thermodynamically easy to form carbon, and thus exhibits excellent activity at a lower temperature. Therefore, development of a catalyst resistant to deactivation by formation of coke and sintering is required.

The conventional catalyst for reforming methane using carbon dioxide is as follows.

Korean Patent No. 1999-0061517 discloses a catalyst in which a nickel metal is supported on a magnesium oxide carrier in which magnesium oxide (MgO) and magnesium oxide-alumina (MgO-Al ₂ O ₃ ) are mixed.

The alumina-based catalyst in the Republic of Korea Patent No. 2001-0046300 M1-M2-Ni / M2- M4-ZrO ₂ were presented by the general formula of the zirconia-supported nickel-based reforming catalyst, in the Republic of Korea Patent No. 2001-0057530 nickel-manganese Respectively.

[J. Chem. Soc., Chem. Commun., 71 (1995) and Inter. J. Hydro. Ene. 28 (2003), 1045, presented a nickel metal supported on a carrier of lanthanum oxide (La ₂ O ₃ ).

Korean Patent No. 2002-0079657 and [A. catal. : A (2005) 200] discloses a catalyst in which nickel metal is supported on the surface of a carrier made of cerium zirconium oxide, and Korean Patent No. 2008-0012661 discloses a catalyst in which nickel metal is supported on a carrier of tungsten carbide (WC) Respectively.

Korean Patent No. 1999-0050013 discloses a nickel-based reforming catalyst in which an alkali metal, an alkaline earth metal, or the like is supported as a cocatalyst together with nickel metal on a zirconia carrier modified with an alkaline earth metal and a Group IIIB or lanthanum group metal in ZrO ₂ .

Korean Patent No. 1993-0016885 discloses a catalyst in which nickel is supported on a silicon-containing support such as zeolite, silica, silicate, and silica-alumina together with an alkali metal and alkaline earth metal co-catalyst. In Korean Patent No. 2000-0002165, A nickel catalyst supported on an airgel carrier was proposed.

Korean Patent No. 2005-0099407 discloses a catalyst for reforming a triple (mixed gas of carbon dioxide, oxygen and water vapor) of methane, which comprises a zirconia carrier doped with a mixed metal containing yttrium as an essential component and a metal selected from a lanthanide element and an alkaline earth metal element Nickel-based catalysts, its activity maintenance, and the effect of prolonging the lifetime of catalysts. It is also suggested that the activity and lifetime of the catalyst may vary with the ratio of oxygen and water vapor.

As described above, attempts have been made to develop a high-performance nickel-supported catalyst having a low cost and resistance to carbon deposition in the same manner as the steam reforming reaction in the reforming reaction of methane using carbon dioxide. However, Confronting. On the other hand, studies have been actively made to apply a noble metal catalyst having disadvantages such as high resistance to carbon deposition and high activity compared with nickel catalysts.

In US Pat. No. 5,066,057, Pt / Al ₂ O ₃ and Pd / Al ₂ O ₃ catalysts are known. In WO 92 / 11,199, noble metal-supported alumina catalysts such as rhodium and ruthenium, Long life span.

International Patent Publication Nos. WO 2004/103555 and WO 2008/099847 disclose a catalyst having copper as an essential element and having at least one element selected from nickel, cobalt and platinum group elements and having a spinel structure as a metal oxide, However, the examples and the like are limited to the methanol and DME steam reforming reaction.

Although iron or iron oxide containing Ti, Zr, V, Nb, Cr, Mo, Al, Ga, Mg, Sc, Ni and Cu has been proposed as a steam reforming catalyst in WO 2002/081368, The reduction rate, H ₂ / CO selectivity and inhibition of deposition of carbon are not enough.

Korean Patent No. 2007-0124923 discloses a catalyst using a composite metal oxide containing Cu-Fe or Sn-Fe, but there is little consideration about deactivation.

Japanese Patent Application Laid-Open No. 11-276893 discloses a reforming reaction of methane with carbon dioxide on a metal oxide catalyst using hydrotalcite as a precursor using noble metals (Rh, Pd, Ru) and transition metal (Ni) as active metals have. However, despite the use of expensive noble metals, the conversion of methane was more than 90% at 800 ° C, but the conversion rate decreased sharply at temperatures below 600 ° C, and catalysts containing 5wt% rhodium (Rh) Conversion rate is about 50%), the conversion rate of methane does not exceed 30%. Further, the lifetime of the catalyst is not mentioned.

U.S. Patent No. 5,744,419 discloses a process for reforming steam and reforming carbon dioxide, including an oxygen reforming reaction, on a support such as silica, alumina, zirconia or the like coated with nickel or cobalt in advance with an alkaline earth metal in accordance with the presence or absence of a noble metal And US Patent No. 4026823 discloses a zirconia supported nickel catalyst in which cobalt is added to nickel as a steam reforming catalyst for hydrocarbons.

Korean Patent Laid-Open Publication No. 2005-0036219 discloses partial oxidation of methane using metal oxide and production of hydrogen using reduced metal oxide. The main active ingredient is iron oxide including cobalt, and is used for improving thermal stability and reactivity. Although it is suggested that materials can be manufactured together, it can cause problems of carbon deposition.

Korean Laid-Open Patent Application No. 2011-0074196 discloses a cobalt-based catalyst for methane and carbon dioxide reforming, but suggests using silica or alumina as a carrier as a carrier.

Japanese Patent Application Laid-Open No. 2008-36451 discloses a catalyst carrier and a method for producing a catalyst for producing a syngas composed mainly of hydrogen and carbon monoxide by reforming methane as a raw material with carbon dioxide in the presence of a catalyst, A nickel or cobalt-based catalyst using a magnesium oxide powder having a pore size of 1 to 5 nm, a small pore volume of 0.2 to 0.4 ml / g and a distillation surface area of 100 to 200 m ² / g was proposed.

U.S. Patent No. 7,097,786 presents a rhodium-spinel catalyst for the production of synthesis gas containing carbon monoxide and hydrogen by partial oxidation of hydrocarbons such as methane or natural gas using a catalyst.

[Kinetics and Catalysis, Vol. 45, No. 2, 2004, pp. 247-255) reported on the catalyst activity in the reforming process of methane using cobalt catalyst supported on silica prepared by sol-gel method and impregnation method, respectively, and their respective carbon dioxide.

[Applied Catalysis A: General 204 (2000) 257-263] proposed a cobalt-based catalyst impregnated with cobalt on a silica, alumina or alkaline earth metal oxide support as a catalyst used in the process of reforming methane using carbon dioxide .

Research on noble metal-based catalysts has been actively carried out, but catalyst studies of catalyst lifetime and activity by carbon deposition have attracted attention.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a method for producing a final high-value-added product by simultaneously processing hydrocarbons such as methane and carbon dioxide, And a method for producing a synthesis gas containing hydrogen and carbon monoxide serving as an intermediate.

It is another object of the present invention to provide a process for preparing a catalyst using a spinel-type carrier as a cobalt-based catalyst for reforming reaction, solving the problem of stability of the catalyst by deactivation of existing nickel-based catalysts. In particular, it is an object of the present invention reduces the side reactions in the reaction using the catalyst according to the effect of the spinel carriers maintain a constant conversion of the hydrocarbon and carbon dioxide, such as methane, and 100,000 ml / g _cat · hr or more space velocity even at high Capacity carbon dioxide conversion catalyst that maintains its activity and stability.

More particularly, the present invention relates to a process for producing a synthesis gas by performing a reforming reaction using a hydrocarbon such as carbon dioxide and methane on a cobalt-based reforming catalyst represented by the following formula (1) or (2) And more particularly, to a method for producing a syngas having a high carbon monoxide content by improving the stability of the catalyst and the catalytic activity over conventional nickel-based reforming catalysts at a high space velocity of carbon dioxide and hydrocarbons.

The present invention relates to a process for producing a cobalt-based catalyst in which a high reaction activity is maintained for a long period of time. More specifically, the present invention relates to a catalyst having durability different from that of a conventional nickel- 2]. &Lt; / RTI >

[Chemical Formula 1]

(a) Co / (d) Z

Wherein Z represents a spinel type carrier comprising A, B and O and A is selected from the group consisting of Mg, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Sn B represents at least one member selected from the group consisting of Al, Ga, In, Ti, V, Cr, Mn, Fe, Ni and Co; Represents a part by weight of the spinel type support Z, and a represents 1 to 100 parts by weight based on 100 parts by weight of the spinel type support d.

(2)

(a) Co- (b) X- (c) Y / (d) Z

X is Pt, Pd, Os, Rh, Ir or Ru, and Y is Zr or La. A represents at least one element selected from the group consisting of Mg, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Sn, and Z represents a spinel type carrier comprising A, B represents at least one member selected from the group consisting of Al, Ga, In, Ti, V, Cr, Mn, Fe, Ni and Co, a represents a weight part of Co, b represents a weight part of X, a represents 1 to 100 parts by weight, b represents 0 to 5.0 parts by weight based on 100 parts by weight (d = 100) of the spinel type support Z, c represents the weight part of Y, d represents the weight part of the spinel type support Z, and c represents 0 to 30 parts by weight, provided that b and c are not both 0. Preferably, b represents 0.001 to 5.0 parts by weight, and c represents 0.1 to 30 parts by weight.

Conventionally, it is generally well known that other transition metals such as cobalt, nickel, and zirconia are used as an active component in the construction of a catalyst used in the reforming reaction of methane and carbon dioxide, and alumina and silica are used as carrier components.

However, it is known that even if the catalysts use the same components, the activity is completely different depending on the mixing ratio of the components, that is, the relative ratio, and it is known that the catalyst is greatly affected by the carrier used. The prior art is based on a specific cobalt among the proposed active ingredients and selectively using the transition metal as described above to adjust the content of the transition metal to an optimum ratio to separately impregnate each active metal and then firing the entire dried active metal To prepare a three-phase cobalt-based catalyst in which an active metal is dispersed in a carrier.

In one embodiment, the present invention provides a method for producing a spinel type carrier, which comprises cobalt (Co) as an active ingredient and is selected from the group consisting of Mg, Cr, Mn, Fe, Co, Ni, Cu, Zn, And at least one element selected from the group consisting of Al, Ga, In, Ti, V, Cr, Mn, Fe, Ni and Co, Type carrier, and the content of the active metal is optimized by the formula (1).

In another embodiment of the present invention, there is provided a method for producing a spinel type carrier, comprising the steps of: cobalt (Co) and a platinum group element as an active component and at least one selected from zirconium (Zr) or lanthanum (La) At least one element selected from the group consisting of Fe, Co, Ni, Cu, Zn, Cd and S is selected from the group consisting of Al, Ga, In, Ti, V, Cr, Mn, Fe, , And oxygen (O), and the content of the active ingredient is optimized by the formula (2).

The present invention also relates to a process for preparing a cobalt-based catalyst by impregnating and drying each active component separately, followed by calcining a carrier impregnated with the entire active metal, and producing a synthesis gas containing carbon monoxide and hydrogen using the catalyst The present invention is characterized in that the activity of the catalyst is high and the activity of the catalyst is maintained.

The present invention also relates to a catalyst prepared by impregnating a cobalt-based catalyst represented by the above formula (1) or (2) with a spinel-type carrier, 0.1 ~ 5.0 MPa, at a space velocity of 500 ~ 500,000 ml / g _cat hr and especially 100,000ml / g _cat hr or more and a space velocity, and the carbon monoxide and hydrogen in a reaction condition that the molar ratio of the hydrocarbon and carbon dioxide, such as methane 0.5-2.0 And a method for producing a synthesis gas containing the same.

In the present invention, platinum group elements include, but are not limited to, Os, Pt, Ru, Rh, Pd and Ir.

In the present invention, the constituent circles of the respective elements are as follows.

As the cobalt component causes the cobalt compound include, but are not limited to, and the like _{Co (NO 3) 2, Co} (OH) 2, CoCl 2, CoSO 4, Co 2 (SO 4) 3, CoF 3 or CoCO _3. As a constituent source of the cobalt, nitrate is generally used.

As the zirconium component causes the zirconium compound include, but are not limited to, _{ZrCl 4, ZrCl 2, ZrO (} NO 3) 2 and _{H 2 O, ZrO 2, Zr} (OH) 4, ZrClOH, Zr (NO 3) 4 and 5H ₂ O , ZrOCl _2, or Zr (SO ₄ ) ₂ . Preferably is Zr (NO ₃₎ ₄ and ZrOCl ₂ 5H ₂ O, or is used in terms of handling.

Examples of the lanthanum compound as the lanthanum component include, but are not limited to, LaCl ₃ , LaCl ₃揃 7H ₂ O, La (OH) ₃ , La (NO ₃ ) ₃ , La (NO ₃ ) ₃揃 6H ₂ O, La ₂ O ₃ , La ₂ (SO ₄ ) ₃揃 8H ₂ O, or LaCl ₃揃 6H ₂ O. As a constituent source of lanthanum, nitrate is generally used.

As the platinum component causes a platinum compound, but are not limited to, _{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 ], Pt (NH ₃ ) ₄ (OH) ₂ or Pt (NH ₃ ) ₂ (NO ₂ ) ₂ .

As the ruthenium component causes ruthenium compounds, but are not limited RuCl ₃ and _{nH2O, Ru (NO 3) 3} , Ru 2 (OH) 2 Cl 4 and 7NH ₃ and _{3H 2 O, K 2 (RuCl} 5 (H 2 O) _{), (nH 4) 2 (} RuCl 5 (H 2 O)), K 2 (RuCl 5 (NO)), RuBr 3 and _{nH 2 O, Na 2 RuO 4} , Ru (NO) (NO 3) 3, ( _{Ru 3 O (OAc) 6 (} H 2 O) 3) OAc and _{nH 2 O, K 4 (Ru} (CN) 6) and _{nH 2 O, K 2 (Ru} (NO 2) 4 (OH) (NO)) _{, (Ru (NH 3) 6} ) Cl 3, (Ru (NH 3) 6) Br 3, (Ru (NH 3) 6) Cl 2, (Ru (NH 3) 6) Br 2, (Ru 3 O 2 (NH ₃₎ ₁₄₎ Cl ₆ and _{H 2 O, (Ru (NO} ) (NH 3) 5) Cl 3, (Ru (OH) (NO) (NH 3) 4) (NO 3) 2, RuCl 2 ( _{PPh 3) 3, RuCl 2 (} PPh) 4, (RuClH (PPh 3) 3) and _{C 7 H 8, RuH 2 (} PPh 3) 4, RuClH (CO) (PPh 3) 3, RuH 2 (CO) ( _{PPh 3) 3, (RuCl 2} (cod)) n, Ru (CO) 12, Ru (acac) 3 or (Ru (HCOO), such as (CO) ₂₎ n I or ₂ Ru ₄ (p- cymene) ₂ Ruthenium salts. Preferably, from the viewpoint of handling, Ru (NO) (NO ₃ ) ₃ or Ru (NO ₃ ) ₃ is used.

Examples of the rhodium compound as the rhodium component include, but are not limited to, Na ₃ RhCl ₆ , (NH ₄ ) ₂ RhCl ₆ , Rh (NH ₃ ) ₅ Cl ₃ or RhCl ₃ .

Examples of the palladium compound as the palladium component include (NH ₄ ) ₂ PdCl ₆ , (NH ₄ ) ₂ PdCl ₄ , Pd (NH ₃ ) ₄ Cl ₂ , PdCl ₂ or Pd (NO ₃ ) ₂ have.

Examples of the iridium compound as the iridium component include, but are not limited to, (NH ₄ ) ₂ IrCl ₆ , IrCl _3, or H ₂ IrCl ₆ .

In the present invention, a catalyst is prepared by impregnating a spinel-type carrier in such a manner that one of various precursors of the main component is selected and optimized with the formula (1) or (2).

In the present invention, the spinel type carrier Z represents a spinel type carrier comprising A, B and O, and A is selected from the group consisting of Mg, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Sn And B represents at least one element selected from the group consisting of Al, Ga, In, Ti, V, Cr, Mn, Fe, Ni and Co, .

In an embodiment of the present invention, the spinel type support Z is represented by the chemical structural formula of AB ₂ O ₄ , O is arranged in cubic closest packing as an oxygen atom, B is bonded to the gaps of the octahedral body, And the oxide crystal structure of AB ₂ O ₄ has 8A, 16B, and 32O ions, and the oxygen ion forms a face-centered cubic lattice, and all the compounds having the structure in which A and B are introduced into each other are possible.

In the present invention, cobalt as the active ingredient may be used in an amount of 1 to 100 parts by weight based on 100 parts by weight of the spinel type carrier. If the weight ratio of (a) is less than 1, the active sites of cobalt as an active metal are too small and the activity is insignificant. If the amount of cobalt exceeds 100 parts by weight, cobalt becomes too much and prevents active sites of metal, .

In the present invention, the optional active component X is selected from Os, Pt, Pd, Rh, Ir or Ru, and the content (b) is in the range of 0 to 5.0 parts by weight based on 100 parts by weight of the spinel type support, To 5.0 parts by weight may be used. (b) is more than 5.0 parts by weight, the active site of the cobalt, which is the main active ingredient, is rather blocked to lower the activity, and the excessive use of the expensive platinum group increases the unit price of the catalyst.

In the present invention, the optional active ingredient Y is selected from Zr or La, and the content (c) is in the range of 0 to 30 parts by weight, preferably 0.1 to 30 parts by weight based on 100 parts by weight of the spinel carrier have. (c) exceeds 30 parts by weight, the active site of the cobalt, which is the main active ingredient, is blocked and the activity is lowered.

The spinel type carrier Z includes at least one selected from the group consisting of A, B and O, and A is at least one selected from the group consisting of Mg, Cr, Mn, Fe, Co, Ni, Cu, Zn, , B represents at least one element selected from the group consisting of Al, Ga, In, Ti, V, Cr, Mn, Fe, Ni and Co, and O represents an oxygen atom.

The component ratios of A and B are included in Z at a content ratio of 1:50 and may be A or B rich. However, it should always contain a spinel type carrier. The amount of the spinel type carrier may be 50 to 99% by weight based on the total catalyst. When the content of the carrier is 50 wt% or less, most of the active metal is occupied, and the pores of the carrier are blocked, thereby failing to exhibit the dispersibility of the active metal and the function of the carrier, resulting in low activity.

On the other hand, in the reforming catalyst of the present invention, when one of the active element cobalt and the spinel type catalyst is removed, the activity of the catalyst is as low as less than 5% or no reaction occurs at all. And a spinel type carrier.

Hereinafter, the production method of the present invention will be described in detail.

First, the production method of the present invention is a method of producing a solution of A by mixing A, which represents at least one selected from the group consisting of Mg, Cr, Mn, Fe, Co, Ni, Cu, Zn, And a step of mixing B, which represents at least one selected from the group consisting of Al, Ga, In, Ti, V, Cr, Mn, Fe, Ni and Co, with a solvent to prepare a solution of B .

The solvent may be, but is not limited to, an inorganic acid such as nitric acid, sulfuric acid or hydrochloric acid, an organic solvent, or distilled water, respectively.

The organic solvent includes, but is not limited to, a hydrocarbon-based organic solvent such as an aliphatic hydrocarbon-based, cyclic hydrocarbon-based or aromatic hydrocarbon-based solvent, a halogenated hydrocarbon-based organic solvent, an alcohol organic solvent, an ether organic solvent, Ketone organic solvents may be used.

Next, the step of preparing a spinel-like carrier by titrating one of the solutions A and B dissolved in the other solution together with the precipitant may be added dropwise.

The above step may be carried out at a temperature of 60 to 150 DEG C, though not limited thereto. If the temperature is lower than 60 ° C, the time loss due to the evaporation of the aqueous solution which is too slow during the production process occurs. If the temperature exceeds 150 ° C, the specific surface area of the catalyst support is reduced due to the evaporation of the aqueous solution, . Further, the pH of the spinel type carrier may be titrated to 6 to 10.

The precipitant may be at least one selected from the group consisting of carbonates of ammonium carbonate, ammonium hydroxide, urea, alkali metal or alkaline earth metal, hydroxides of alkali metal or alkaline earth metal, though not limited thereto.

In addition, the present invention may further include a step of filtering the spinel carrier, washing the carrier with distilled water or an organic solvent, and drying and firing the spinel carrier. At this time, the same organic solvent as that used as the solvent of A or B may be used.

Next, the present invention includes a step of mixing and impregnating the spinel type carrier with an active metal to prepare a catalyst.

The active metal may be Co, or Co with at least one selected from X and Y, X is selected from Os, Pt, Pd, Rh, Ir, or Ru, and Y is selected from Zr or La. At this time, the content of Co, X and Y is determined by the above-mentioned formula (1) or (2).

Next, the catalyst is dried and calcined.

The drying step is not limited thereto, but may be carried out at a temperature of 60 to 150 ° C under an air atmosphere.

The firing step is not limited thereto, but may be performed at 200 to 1200 ° C. If the temperature is less than 200 ° C, the physical properties of the catalyst and the precursors are not evaporated sufficiently, and the chemical structural bonding between the cobalt and the carrier is not achieved. When the temperature exceeds 1200 ° C, the degree of oxidation of the catalyst, Is stabilized and can not function as a catalyst, it is preferable to maintain the above range.

In another embodiment, the carrier-supported sludge can be dried for about 48 hours at a temperature of 80-100 ° C to remove moisture. The size may be selected to be 60-120 mesh, and the firing process may be performed at 200-1200 ° C for 5-48 hours in an air atmosphere to sort out the structure of the precursor of the catalyst and the structure of the metal oxide.

According to the above production method, the catalyst of the present invention can be produced by impregnating a solution obtained by dissolving Co of Formula 1 or Co, X and Y in a solvent such as distilled water in the same manner as in the previously prepared spinel type carrier And a metal component is supported on the spinel type carrier.

In general, hydrocarbons such as methane and carbon dioxide reforming catalysts can perform a role as a catalyst through a reduction reaction by an appropriate pretreatment process before a reaction. However, the catalyst of the present invention prevents carbon deposition, which is the main cause of inactivation of the catalyst due to the oxides present on the surface of the catalyst without reduction process, thereby stabilizing the activity of the catalyst.

The reactor for reforming the hydrocarbon and carbon dioxide is not particularly limited and is generally used in the art, and specifically, a gas phase fixed bed reactor, a fluidized bed reactor, a liquid slurry type reactor or a batch reactor may be used. The reaction conditions are maintained at a reaction temperature of 500 to 1000 ° C, a pressure of 0.01 to 1 MPa, a space velocity of 500 to 500,000 ml / g _cat. Hr, and a molar ratio of hydrocarbon to carbon dioxide as a reaction raw material is maintained in the range of 0.5 to 2.0.

If the reaction temperature is less than 500 ° C, the reaction rate is not sufficient and conversion does not occur. If the reaction temperature exceeds 1000 ° C, carbonization of the catalyst starts and the catalyst is deactivated early. When the reaction pressure is increased, the activity of the catalyst is stably maintained, but it is not a large variable, and the pressure of 0.1 MPa or more causes a large initial reactor installation cost.

If the space velocity of the mixed gas is less than 500 ml / g _{cat.hr, the} reaction productivity is lowered and the addition reaction by the long contact time causes the deactivation of the catalyst. If the space velocity exceeds 500,000 ml / g _cat.hr , And the reaction activity of the catalyst is small. If the mixing ratio of the hydrocarbon and the carbon dioxide is out of the above range, the reaction may be skewed at one of the conversions, resulting in an ineffective reaction.

As described above, the catalyst prepared according to the present invention can be obtained by preparing a spinel-type support by a precipitation method, drying and firing the precipitate, and adding a metal of the above formula (1) or (2) And dispersed uniformly on the surface of the carrier. The prepared catalyst can be effectively applied to the activation of the reforming reaction of hydrocarbon and carbon dioxide through a drying step and a baking step without the necessity of a reducing step. Compared with the conventional reforming reaction activity of hydrocarbons and carbon dioxide, it is possible to produce a synthesis gas having a high conversion ratio and a particularly high carbon monoxide ratio, and the conversion of hydrocarbon and carbon dioxide occurs simultaneously to maintain stable activity. The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. When the content of the carrier is determined, the components of the catalyst of the present invention are determined in accordance with the mass ratio thereof.

Example

Example 1

The precursors Mg (NO ₃ ) ₂ and Al (NO ₃ ) ₃ were dissolved in distilled water so that the ratio of the spinel structure MgO / Al ₂ O ₃ was 0.1, and the precipitant Na ₂ CO ₃ was added thereto Lt; / RTI > The precipitate was filtered with distilled water to remove Na dissolved in the precipitate. The filtered precipitate was calcined at 500 캜 to prepare a spinel type carrier.

Mg / Al ₂ O _{4 as a} carrier was prepared to be 80 wt%, mixed with 200 mL of distilled water, and Co (NO ₃ ) ₃ .9H ₂ O was dissolved in distilled water so as to have a ratio of 20 wt% Co. The mixed slurry was distilled using a vacuum distillation apparatus to prepare powder. The powder was dried at 80 ° C for 3 hours and then fired at 400 ° C for 6 hours in an air atmosphere. The above prepared catalyst was performed 850 ℃, 0.1MPa, 100,000ml / g cat and a flow rate of reaction of methane with a ratio of the molar ratio of carbon dioxide of 1.0 hr in a fixed bed reactor. Conversion rates of methane and carbon dioxide were 96% and 95%, respectively. After 48 hours, the activity remained at 96% and 95%, respectively.

Example 2

MgO / Al ₂ O _{3 as a} carrier was prepared so as to be 80 wt%, mixed with 200 mL of distilled water, and mixed with Co (NO ₃ ) ₃ .9H ₂ O, Ru (NO) - (NO ₃ ) ₃ were dissolved in distilled water and mixed. The mixed slurry was distilled using a vacuum distillation apparatus to prepare powder. The powder was dried at 80 ° C for 3 hours and then fired at 400 ° C for 6 hours in an air atmosphere. The above prepared catalyst was performed 850 ℃, 0.1MPa, 100,000ml / g cat and a flow rate of reaction of methane with a ratio of the molar ratio of carbon dioxide of 1.0 hr in a fixed bed reactor. Conversion rates of methane and carbon dioxide were 89% and 92%, respectively. After 48 hours, the activity was maintained at 90% and 92%, respectively.

Example 3

Mg / Al ₂ O _{4 as a} carrier was prepared so as to be 80wt% and mixed with 200ml of distilled water to obtain Co (NO ₃ ) ₃揃 9H (weight ratio) as a ratio of 14.86wt% Co-0.14wt% Ru-5wt% ₂ O, ZrOCl ₂ , and Ru (NO) (NO ₃ ) ₃ were dissolved in distilled water and mixed. The mixed slurry was distilled using a vacuum distillation apparatus to prepare powder. The powder was dried at 80 ° C for 3 hours and then fired at 400 ° C for 6 hours in an air atmosphere. The prepared catalyst was reacted in a fixed bed reactor at a flow rate of 100,000 ml / g _cat . Hr at 850 ° C, 0.1 MPa, and a molar ratio of methane to carbon dioxide of 1.0. Conversion rates of methane and carbon dioxide were 94% and 95%, respectively, and 98% and 97% after 48 hours, respectively.

Example 4

The precursors Mg (NO ₃ ) ₂ and Al (NO ₃ ) ₃ were dissolved in distilled water so that the ratio of MgO / Al ₂ O ₃ , which is a spinel structure, was 0.3, and then the precipitant Na ₂ CO ₃ was added thereto Lt; / RTI > The precipitate was filtered with distilled water to remove Na dissolved in the precipitate. The filtered precipitate was calcined at 500 캜 to prepare a spinel type carrier.

Mg / Al ₂ O _{4 as a} carrier was prepared so as to be 80wt% and mixed with 200ml of distilled water to obtain Co (NO ₃ ) ₃揃 9H (weight ratio) as a ratio of 14.86wt% Co-0.14wt% Ru-5wt% ₂ O, ZrOCl ₂ , and Pt (NO ₃ ) ₂ were dissolved in distilled water and mixed. The mixed slurry was distilled using a vacuum distillation apparatus to prepare powder. The powder was dried at 80 ° C for 3 hours and then fired at 400 ° C for 6 hours in an air atmosphere. The above prepared catalyst was performed 850 ℃, 0.1MPa, 150,000 ml / g at a rate of reaction that the mole ratio of methane and carbon dioxide at a flow rate of 1.0 _cat hr and in a fixed bed reactor. Conversion rates of methane and carbon dioxide were 98% and 97%, respectively, and 98% and 97% after 48 hours, respectively.

Example 5

The precursors Mg (NO ₃ ) ₂ and Mn (NO ₃ ) ₂ were dissolved in distilled water so that the ratio of Mg / Mn, which is a spinel structure, was 0.3, and the precipitate Na ₂ CO ₃ was added to precipitate the solution so that the pH was 8.0 . The precipitate was filtered with distilled water to remove Na dissolved in the precipitate. The filtered precipitate was calcined at 500 캜 to prepare a spinel type carrier.

Mg / Mn ₂ O _{4 as a} carrier was prepared so as to be 80 wt% and mixed with 200 mL of distilled water. Co (NO ₃ ) ₃ .9H (molar ratio) was added so as to have a ratio of 14.86 wt% Co-0.14 wt% Ru-5 wt% ₂ O, La (NO ₃ ) ₃ (H ₂ O) ₆ and Ru (NO) 揃 (NO ₃ ) ₃ were dissolved in distilled water and mixed. The mixed slurry was distilled using a vacuum distillation apparatus to prepare powder. The powder was dried at 80 ° C for 3 hours and then fired at 400 ° C for 6 hours in an air atmosphere. The prepared catalyst was reacted in a fixed bed reactor at a flow rate of 100,000 ml / g _cat . Hr at 850 ° C, 0.1 MPa, and a molar ratio of methane to carbon dioxide of 1.0. Conversion rates of methane and carbon dioxide were 92% and 93%, respectively, and the activities were maintained at 92% and 93% after 48 hours, respectively.

Example 6

The precursors Fe (NO ₃ ) ₃ .9H ₂ O and Cr (NO ₃ ) ₃ .9H ₂ O were dissolved in distilled water so that the Fe / Cr ratio of the spinel structure was 0.1, and the precipitant Na ₂ CO ₃ was added and the pH was adjusted to 8.0. The precipitate was filtered with distilled water to remove Na dissolved in the precipitate. The filtered precipitate was calcined at 700 캜 to prepare a spinel type carrier.

Mg / Al ₂ O _{4 as a} carrier was prepared so as to be 80wt% and mixed with 200ml of distilled water to obtain Co (NO ₃ ) ₃揃 9H (weight ratio) as a ratio of 14.86wt% Co-0.14wt% Ru-5wt% ₂ O, La (NO ₃ ) ₃ (H ₂ O) ₆ and Ru (NO) 揃 (NO ₃ ) ₃ were dissolved in distilled water and mixed. The mixed slurry was distilled using a vacuum distillation apparatus to prepare powder. The powder was dried at 80 ° C for 3 hours and then fired at 400 ° C for 6 hours in an air atmosphere. The prepared catalyst was reacted in a fixed bed reactor at a flow rate of 100,000 ml / g _cat . Hr at 850 ° C, 0.1 MPa, and a molar ratio of methane to carbon dioxide of 1.0. Conversion rates of methane and carbon dioxide were 92% and 94%, respectively, and 98% and 97% after 48 hours, respectively.

Example 7

The precursor of the spinel structure Zn / Fe ratio to be 0.3 Zn (NO ₃₎ ₂ and 6 (H ₂ O) and Fe (NO ₃₎ ₃ and precipitant Na ₂ CO ₃ and a 9H ₂ O was stirred and then dissolved in distilled water And the pH was adjusted to 8.0. The precipitate was filtered with distilled water to remove Na dissolved in the precipitate. The filtered precipitate was calcined at 700 캜 to prepare a spinel type carrier.

Mg / Al ₂ O _{4 as a} carrier was prepared so as to be 80wt% and mixed with 200ml of distilled water to obtain Co (NO ₃ ) ₃揃 9H (weight ratio) as a ratio of 14.86wt% Co-0.14wt% Ru-5wt% ₂ O, La (NO ₃ ) ₃ (H ₂ O) ₆ and Ru (NO) 揃 (NO ₃ ) ₃ were dissolved in distilled water and mixed. The mixed slurry was distilled using a vacuum distillation apparatus to prepare powder. The powder was dried at 80 ° C for 3 hours and then fired at 400 ° C for 6 hours in an air atmosphere. The above prepared catalyst was performed 850 ℃, 0.1MPa, 100,000ml / g cat and a flow rate of reaction of methane with a ratio of the molar ratio of carbon dioxide of 1.0 hr in a fixed bed reactor. Conversion rates of methane and carbon dioxide were 95% and 95%, respectively, and the activities were maintained at 95% and 94% after 48 hours, respectively.

Comparative Example 1

The precursor, Co (NO ₃ ) ₃ .9H ₂ O, was titrated to 80 wt% alumina gel based on the carrier and 14.9 wt% Co, mixed with distilled water and reacted at 80 ° C for 6 hours. Next, a solution obtained by dissolving ZrOCl ₂ in distilled water such that the Zr was 4.33 wt% and Ru (NO ₃ ) (NO ₃ ) ₃ were titrated so that Ru was 0.14 wt% and reacted at 80 ° C for 12 hours. Next, the resultant was dried at 80 DEG C for 3 hours and then calcined at 300 DEG C for 6 hours. The prepared catalyst was reacted in a fixed bed reactor at a flow rate of 850 ° C, 0.1 MPa, and 20000 ml / g _cat . Hr at a molar ratio of methane to carbon dioxide of 1.0. Conversion rates of methane and carbon dioxide were 86% and 98%, respectively, but were inactivated to 52% and 64% after 48 hours.

Comparative Example 2

The catalyst prepared by the production process of Comparative Example 1 was carried out by reaction under the conditions other than the space velocity 100,000ml / g _cat and hr. Conversion rates of methane and carbon dioxide showed a low conversion rate of 10% due to fast contact time.

Comparative Example 3

The reaction was carried out under the same conditions as in Example 1 except that a catalyst carrying nickel on alumina having a specific surface area of 180 m ² / g, which is generally used as a catalyst carrier, was used for the carbon dioxide reforming reaction activity of methane. The initial methane and carbon dioxide conversion rates were 72% and 79%, respectively. However, after 3 hours, the extreme caulking caused the conversion rate to drop and the flow of gas became impossible.

Comparative Example 4

Mg / Al ₂ O _{4 as a} carrier was prepared so as to be 80 wt%, mixed with 200 mL of distilled water, and Ni (NO ₃ ) ₂ .6H ₂ O was dissolved in distilled water so that the ratio of Ni was 20 wt% . The mixed slurry was distilled using a vacuum distillation apparatus to prepare powder. The powder was dried at 80 ° C for 3 hours and then fired at 400 ° C for 6 hours in an air atmosphere. The above prepared catalyst was performed 850 ℃, 0.1MPa, 100,000ml / g cat and a flow rate of reaction of methane with a ratio of the molar ratio of carbon dioxide of 1.0 hr in a fixed bed reactor. Conversion rates of methane and carbon dioxide were 82% and 90%, respectively, but after 7 hours, the conversion rate was reduced due to extreme caulking and gas flow became impossible.

Comparative Example 5

Powders obtained by dissolving the respective precursors in water so as to be 85.31 wt% SiO ₂ , 10 wt% Co, 0.4 wt% Ru, and 4.3 wt% Zr by using a high surface area silica Davisil 645 as a commercial carrier and then distilling off under reduced pressure at 60 ° C Was dried at 80 占 폚 and then calcined at 300 占 폚 and an air flow to carry out the reaction under the same conditions as in Example 1. [ The initial methane conversion rate was 52% and the carbon dioxide conversion rate was 69%. After 48 hours, the conversion rate decreased to 48% and 60%, respectively.

Comparative Example 6

The catalyst was prepared only with cobalt and silica components in the same manner as in Example 1, and the reaction was carried out under the same conditions. Methane and carbon dioxide, however, remained almost unchanged at 700 ℃. At 850 ℃, the methane conversion was 35% and the carbon dioxide conversion was 56%. After 48 hours, the conversion was decreased to 30% and 52%, respectively.

Catalyst evaluation

In order to compare the performance of the catalysts prepared in Examples 1 to 7 and Comparative Examples 1 to 6, the reforming reaction of methane and carbon dioxide was carried out in the following manner.

First, the catalyst prepared according to each of Examples 1 to 7 and Comparative Examples 1 to 6 was packed with 0.2 g of catalyst having a size of 10 to 14 mesh. The test equipment consists of a fixed-bed tubular reactor with external heating system, made of quartz with a length of 350 mm and an internal diameter of 9.25 mm. The molar ratio of the mixed gas of methane and carbon dioxide was 1.0, and the reactor was fed at a flow rate of 20,000 to 100,000 ml / g _cat.h. The reaction temperature was 850 ℃ at atmospheric pressure. The gas released after the reaction was analyzed by the on - line gas chromatography system.

As shown in the following Table 1, Examples 1 to 7 of the present invention show the same conversion rates of methane and carbon dioxide at a space velocity of 100,000 ml / g _cat . Hr and about 95% or more, and the reaction was maintained over time. On the other hand, the embodiment with the active compared as a support of a metal and silica Example 1 20,000 ㎖ / g at the lower space velocity of _cat and hr the conversion of methane and carbon dioxide, look for high activation degree of about 86 and 98%, methane and carbon dioxide Conversion rate is different. In Comparative Example 2, the catalyst prepared as in Comparative Example 1 was changed to a space velocity of 100,000 ml / g _cat.hr and the remainder was reacted under the same reaction conditions as in Example 1, but the conversion was as low as 10%. In Comparative Examples 3 to 6, the respective catalysts were prepared and reacted at different space velocities of 20,000 ml / g _cat.hr , but the conversion was lower than those of Examples 1 and 2 and easily inactivated.

1 is an XRD pattern showing the structural analysis of the catalyst prepared according to Example 1 by XRD. (A) is the catalyst prepared in Comparative Example 1, and (B) is the catalyst prepared in Example 1. (A) could confirm the crystal phase of Co ₃ O ₄ , and (B) it could confirm that the spinel structure of Co ₃ O ₄ and MgAl ₂ O ₄ appeared simultaneously.

As shown in the above results, the methane and carbon dioxide reforming reaction in the preparation of the catalyst including all the components of the general formula (1) can convert a large amount of CO ₂ and CH ₄ into a high synthesis gas at a high space velocity, And the addition reaction is less than that of the existing cobalt catalyst, so that the conversion stability of CO ₂ and CH ₄ is maintained. As a result, the synergistic effect of the spinel structure of the carrier and the active metal is superior to the conventional catalyst.

[(a) Co - (b) X - (c) In Y, a, b and c represent weight ratios to the carrier, respectively. The content d of the carrier is the remaining weight ratio to the weight ratio of the active metal.

According to the present invention, the support having a spinel structure can exhibit stable and high activity even at a high space velocity in the reaction of carbon dioxide dry reforming of the present catalyst. In particular, it shows a constant conversion of carbon dioxide and methane over conventional cobalt-based catalysts. This catalyst is expected to be useful as a clean technology for the utilization of emission trading in the Convention on Climate Change, which is a stable catalyst and has a high production ratio of carbon monoxide and the like.

1 is an XRD pattern showing the structural analysis of the catalyst prepared according to Example 1 by XRD. (A) is the catalyst prepared in Comparative Example 1, and (B) is the catalyst prepared in Example 1. (A) can confirm the crystal phase of Co ₃ O ₄ , and (B) can confirm that the spinel structure of Co ₃ O ₄ and MgAl ₂ O ₄ appears at the same time.

Claims

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A catalyst for producing a synthesis gas from hydrocarbons and carbon dioxide, which is represented by the following formula (2).
(2)
(a) Co- (b) X- (c) Y / (d) Z
Wherein X represents Os, Pt, Pd, Rh, Ir or Ru, Y represents Zr or La, Z represents a spinel type carrier comprising A, B and O, A represents Mg, Cr, Mn , B, at least one element selected from the group consisting of Al, Ga, In, Ti, V, Cr, Mn, Fe, Ni and Co; B is the weight part of X, c is the weight part of Y, d is the weight part of the spinel type carrier, and the spinel type carrier d A is from 1 to 100 parts by weight, b is from 0 to 5.0 parts by weight, and c is from 0 to 30 parts by weight, provided that b and c are not all 0,

The catalyst according to claim 2, wherein X is Ru, Y is La, A is Mg, and B is Al.

The spinel type carrier Z is represented by a chemical structural formula of AB ₂ O ₄ , O is arranged as an oxygen atom in the cubic closest packing, B in the gaps in the octahedral shape and A in the gaps in the tetrahedral shape And the oxide crystal structure of the composition AB ₂ O ₄ has 8A, 16B, and 32O ions, and the oxygen ion forms a face-centered cubic lattice, and A and B are included therein.

A process for producing a catalyst for synthesis gas according to claim 2, characterized by comprising the steps of:
(1) preparing a solution of A by mixing A with at least one solvent selected from the group consisting of Mg, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Sn;
(2) mixing B, which represents at least one selected from the group consisting of Al, Ga, In, Ti, V, Cr, Mn, Fe, Ni and Co, with a solvent to prepare a solution of B;
(3) preparing a spinel-type carrier by titrating one of the solution A and the solution B with the other solution together with a precipitant; And
(4) mixing and impregnating the spinel type carrier with at least one selected from X or Y and Co;
X is selected from Os, Pt, Pd, Rh, Ir, or Ru, Y is selected from Zr or La, 1 to 100 parts by weight of Co, 0 to 5.0 parts by weight of Co relative to 100 parts by weight of the spinel- 0 to 30 parts by weight of Y and 0 parts by weight of X and Y are used at the same time.

[6] The method of claim 5, wherein the step (4) comprises mixing and impregnating at least one selected from the group consisting of X and Y and Co with a spinel type carrier, wherein Co is contained in an amount of 1 to 100 parts by weight , 0.001 to 5.0 parts by weight of X, and 0.1 to 30 parts by weight of Y are mixed and impregnated.

The method for producing a catalyst according to claim 5 or 6, further comprising the step of drying and calcining the product of the step (4).

A process for producing a synthesis gas comprising carbon monoxide and hydrogen from a gas comprising carbon dioxide and hydrocarbons using the catalyst of claims 2 or 3.

The method of claim 8, wherein the synthesis gas is produced by non-reduction pretreatment of the catalyst.

The process for producing a synthesis gas according to claim 8, wherein the synthesis gas is produced under a gas having a hydrocarbon / carbon dioxide molar ratio of 0.5 to 2.0.

The method according, 500 ~ 900 ℃ temperature, 0.01 ~ 1MPa synthesis gas, characterized in that for producing a synthesis gas under conditions of pressure and space velocity of 500 ~ 500,000ml / g _cat hr and of the claim 8.

The process according to claim 8, wherein the reaction of the hydrocarbon with carbon dioxide is carried out in a fixed-bed reactor, a fluidized bed reactor, a slurry reactor or a batch reactor.