KR101958770B1 - Heterogeneous catalyst using carbon nitride support containing rhodium, palladium, the manufacturing method thereof, manufacturing method of acetic acid using the same, and acetic acid manufactured thereby - Google Patents

Abstract

The present invention is an alcohol carbonylation catalyst, wherein the catalyst is a heterogeneous catalyst containing a carbon nitride support and rhodium and palladium, wherein the rhodium and palladium are dispersed within the carbonnitride network, A method for producing acetic acid using the same, and acetic acid produced by the method.
By using the heterogeneous catalyst of the present invention, it is possible to remarkably reduce the amount of rhodium, which is a noble metal contained in the catalyst compared to the conventional process, while maintaining the existing activity such as methanol conversion and selectivity to acetic acid.

Description

Rhodium and palladium, a process for producing acetic acid, a process for producing acetic acid using the same, and a process for producing acetic acid using the same, acid using the same, and acetic acid.

The present invention relates to a catalyst used for synthesizing acetic acid through carbonylation reaction between methanol and carbon monoxide, a process for producing the same, a process for producing acetic acid using the same, and acetic acid produced thereby.

The development of renewable alternative energy sources is being critically dealt with due to limited reserves of fossil fuels and global warming and air pollution problems. Nonfossil energy sources include hydroelectric power, intelligent power, wind power, solar heat, and geothermal power, and biofuel and hydrogen, which are currently in the spotlight. Among them, methanol is a practical alternative to alternative energy resources and currently produces formaldehyde (38%), methyl-tert-butyl ether (20%) and acetic acid (11%) using methanol as one of the most important supply materials in the chemical industry. , Which has the advantage of producing industrially valuable products for a wide range of applications.

There is a carbonylation reaction using methanol and carbon monoxide as a method of producing acetic acid. The Monsanto process, which was invented in the early 1960s, uses homogeneous catalysts prepared by chemical bonding of functional groups such as carbonyl group (-CO) and iodide (Iodide, -I) to rhodium metal, Productivity. In the Cativa process, which is a similar homogeneous catalytic reaction but uses iridium as a reactive active material and has a much higher productivity than the existing Monsanto process and reduces the possibility of producing by-products by reducing the content of water as a promoter [EP Patent 752406 (1995)].

Both of these processes have high conversion of methanol and high acetic acid selectivity due to the homogeneous catalytic reaction involving rhodium. However, rhodium and iridium (Iridium, Ir) are adsorbed on the resultant, , Hereinafter referred to as " leaching ") phenomenon occurs and a separate process for separating the resultant and the catalyst is required, which causes a great economic cost. Heterogenized-homogeneous catalysis has been introduced by adsorbing and immobilizing a homogeneous catalyst on a support, and a representative process thereof is to use poly 4-vinyl pyridine (P4VP) as a support, US Pat. No. 5,564,453 (1996)) discloses an Acetic acid process ( ^TM ) in which a heterogeneous catalyst using rhodium ion is prepared as an active material of the catalytic reaction and carbonylation reaction of methanol is carried out. . In the case of the acetacid process, the re-use of the catalyst and the recovery of the catalyst from the resultant catalyst are easy, but the conversion of methanol and the selectivity of acetic acid are relatively low due to the low rhodium content as a reactive component per catalyst. There is a problem that the process is inevitably restricted due to the deactivation of the catalyst due to thermal deformation under the process conditions at high pressure and high temperature.

Therefore, studies on the preparation of a catalyst capable of showing the activity and performance of the catalyst as seen in a homogeneous catalyst while retaining the recoverability of the catalyst of the acetic process have been continued.

United States Patent 3769329

It is an object of the present invention to provide a heterogeneous catalyst containing rhodium and palladium for the carbonylation reaction of methanol and carbon monoxide and to provide a reaction utilizing the heterogeneous catalyst. One of copper (Cu), platinum Pt, iridium (Ir), iron (Fe), and iron (Pd) is selected based on the rhodium element used in the homogenization process (5-x) -gC ₃ N ₄ (M = Cu, Fe, Ir, Pd, Pt) by physically immobilizing the active material of the double metal structure contained in the catalyst on the support, , And to provide synthesized acetic acid by carbonylation reaction of methanol and carbon monoxide using the catalyst.

Another object of the present invention is to provide a process for the production of carbonitrides by reacting carbonitrides as a support with rhodium and palladium as an active material in the case where the catalyst proposed in the present invention is utilized for the carbonylation reaction of methanol, The catalyst can be easily separated from the resultant product by a simple process such as separation or suspension after completion of the reaction and the active material is re-precipitated in the reaction product The present invention provides a development method applicable to a catalytic reaction process of methanol carbonylation in that the stability of the catalyst and the long-term performance can be secured by minimizing the phenomenon.

It is a further object of the present invention to provide a process for the preparation of catalysts which can reduce the amount of rhodium, a noble metal, Which can maintain the activity of the heterogeneous catalyst in the homogeneous catalyst process, and to provide a method for producing the heterogeneous catalyst.

A first aspect of the present invention is an alcohol carbonylation catalyst, wherein the catalyst contains rhodium and palladium on a carbon nitride support, and wherein the rhodium and palladium are dispersed within the carbon nitride network. Catalyst.

The second aspect of the present invention is a method for producing a rhodium and / or rhodium-based composite material, which comprises melting a surface by using a melamine resin as a carbon source and a rhodium precursor and a palladium precursor under a nitrogen atmosphere at a temperature of 500 ° C to 550 ° C, Preparing a carbon nitride support containing palladium, wherein the rhodium and palladium are dispersed and positioned inside the network of carbonitrides.

A third aspect of the present invention is a process for producing a methanol-containing solution, comprising the steps of: introducing a carbon monoxide-containing gas into a methanol-containing solution at a pressure of 10 bar to 200 bar in the presence of a heterogeneous catalyst according to the first aspect, , And carbonylating methanol with carbon monoxide.

A fourth aspect of the present invention provides acetic acid prepared by the process of the third aspect.

Hereinafter, the present invention will be described in detail.

The heterogeneous catalyst of the present invention is characterized by a heterogeneous catalyst having Rh (x) Pd (5-x) -gC ₃ N ₄ structure based on carbon nitride and rhodium as supports.

The carbon nitride support has a specific surface area of 0.5 m ² / g to 100 m ² / g, and may be a porous structure.

The catalyst of the present invention is a heterogeneous catalyst capable of increasing the selectivity of acetic acid as a result of the conversion of methanol and carbon monoxide and the progress of the reaction by controlling the composition of the rhodium compound having a bimetallic effect and the content of rhodium.

The total content of rhodium and palladium may be 0.2 wt% to 10 wt% based on the weight of the carbon nitride support.

 Generally, the acetic acid synthesis method is a synthesis method directly from the carbonylation reaction between methanol and carbon monoxide as shown in Scheme 1.

[Reaction Scheme 1]

_{CH 3 OH + CO → CH 3} COOH

Homogeneity of Carbonylation Reaction of Methanol and Carbon Monoxide The main catalytic metal components used in the catalytic reaction are rhodium and iridium, and iridium used as an accelerator is known to improve the rate of the carbonylation reaction [EP Patent 752406 (1995)). However, the two catalysts have a fatal disadvantage that the active metal is liable to be re-precipitated in the homogeneous catalytic reaction condition.

The carbon nitride used as a support in the present invention is a carbon material containing nitrogen represented by the formula C ₃ N ₄ . Carbon nitride is a binary compound in which carbon and nitrogen form a covalent bond. It is a carbon nitride of alpha, beta, cubic, pseudocubic, and graphitic (graphitic) .

The graphite-type carbon nitride has the advantage that meso-sized spherical pores are regularly arranged and three-dimensionally interconnected and has a high nitrogen content, thereby facilitating internal electron transfer. Carbon nitride containing rhodium and palladium The rid has a large internal Lewis acidic retention and can serve as a catalyst for catalytic-reaction interactions from electron transport and is advantageous in that the metal compound is immobilized on a carbon nitride support.

 In the present invention, the active material is contained in a carbon nitride structure rich in internal electrons, thereby enhancing the dispersibility of the catalytically active material and enhancing the activity of the catalyst by enhancing the interaction between the support and the catalytically active material. In addition, rhodium forms a double metal structure with palladium, thereby reducing the amount of rhodium supported on the support to suppress the rhodium metal re-nicking and the inactivation of the catalyst due to self-aggregation of the rhodium element, Thereby increasing the possibility of ensuring the performance of the catalyst.

On the other hand, the present invention can be expressed as Rh (x) Pd (5-x) -gC ₃ N ₄ .

Here, x may be a positive number from 0.1 to 4.9. Preferably 1.25 to 3.5.

The content ratio of rhodium and palladium may be 5-X when palladium is X.

The alcohol may be methanol or ethanol.

The method for producing a heterogeneous catalyst is also characterized. According to the catalyst production method proposed in the present invention, rhodium nitrate as a rhodium precursor and palladium nitrate as a palladium precursor are mixed with a melamine resin used as a carbon source so that rhodium (Rh) and palladium x) Pd (5-x) -gC ₃ N ₄ precursor under a nitrogen (N ₂ ) atmosphere to a temperature of 500 ° C to 550 ° C to produce a rhodium palladium carbon nitride support. In the above method, nitrides, chlorides and organometallic compounds can be used as the precursors of rhodium and palladium. Specifically, the total content of rhodium and palladium, which are active metals, can be fixed in the range of 0.2 wt% to 10 wt% with respect to the weight of the support.

If the total content of the active metal is less than 0.2 wt%, the target catalyst activity can not be attained. If the total amount of the active metal exceeds 10 wt%, the activity of the catalyst is high. However, the use of expensive rhodium and palladium And the economical efficiency of the process may decrease. Accordingly, the content range proposed in the present invention will be a suitable content of rhodium and palladium.

The process for producing rhodium and palladium-containing carbon nitride heterogeneous catalysts according to the present invention will be described in more detail as follows.

That is, a melamine resin is used as a carbon source, and a rhodium precursor and a palladium precursor are used for heat treatment at a temperature of 500 ° C to 550 ° C under a nitrogen atmosphere to cure the surface. Carbon containing rhodium and palladium Preparing a nitrided support, wherein the rhodium and palladium are dispersed and positioned within the network of carbonitrides.

The network may refer to the interior of the structure formed through the combination of carbon and nitrogen.

Carbon nitride support is prepared by heating melamine resin to a temperature of 500 to 550 DEG C under a nitrogen atmosphere using a carbon source. The carbon nitride support is heated by heating at 500 to 550 DEG C under a nitrogen atmosphere, Thereby preparing a carbon nitride support.

The rhodium precursor may be at least one selected from the group consisting of rhodium chloride, rhodium nitrate, dichlorotetracarbonyl di rhodium, acetylacetonato dicarbonyl rhodium, acetylacetone diisobutylene rhodium and dicarbonylpentamethylcyclopentadienyl rhodium .

The palladium precursor may be at least one selected from palladium chloride, palladium nitrate, sodium tetrachloropalladate, potassium tetrachloropalladate, and palladium chloride.

The carbon nitride support has a specific surface area of 0.5 m ² / g to 100 m ² / g, and may be porous.

The melamine resin may be in powder form.

The preparation method may use a mixed solution in which the melamine resin, the rhodium precursor and the palladium precursor are dissolved.

Specifically, a melamine resin powder is used as a carbon source, and the temperature is raised to 200 ° C to 250 ° C at a rate of about 1 to 3 ° C / minute in a nitrogen atmosphere, held for 20 to 40 minutes, The reaction temperature is raised to 300 ° C. to 350 ° C. and maintained for 20 to 40 minutes. Finally, the reaction temperature is raised to 500 ° C. to 550 ° C. at a temperature rising rate of about 1 to 3 ° C./min. A carbon nitride support is prepared. The melamine resin undergoes condensation and thermal decomposition reaction through the temperature raising rate and temperature gradient suggested in the support preparation process to obtain a powdery carbon nitride support by re-rering of carbon and nitrogen .

In addition, in the process of synthesizing the carbon nitride support, powdery melamine was mixed with distilled water, a solution prepared by dissolving rhodium precursor in nitric acid in the solution, and palladium nitrate as a palladium precursor were mixed in an appropriate amount, After stirring, the resultant was dried under reduced pressure at the same temperature and dried in a circulating drier maintained at 80 ° C to prepare powdered melamine rhodium palladium precursor. Thereafter, a heterogeneous catalyst in which rhodium and palladium are contained in the carbon nitride can be produced by the same method using the carburizing method for producing the carbon nitride support described above.

On the other hand, the present invention is characterized in that Rh (x) Pd (5-x) -gC ₃ N ₄ And a method for producing acetic acid by a carbonylation reaction of methanol using a heterogeneous catalyst.

That is, in the presence of the heterogeneous catalyst according to the first aspect, the step of introducing carbon monoxide-containing gas into the methanol-containing solution at a pressure of 10 bar to 200 bar at a temperature of 50 ° C to 200 ° C, May be a method for producing acetic acid which is carbonylated.

The methanol containing solution may contain methanol as the reactant and iodomethane and water as the cocatalyst.

The mixing ratio of the methanol: iodomethane: water may be 10 to 80:10 to 60:10 to 30 by weight.

The carbonylation reaction uses methanol and carbon monoxide as reactants, and includes iodomethane (CH ₃ I) and distilled water as an activity enhancer. Specifically, the molar ratio of methanol / iodomethane / distilled water as the liquid reaction product is maintained in the range of (10 to 80) / (10 to 60) / (10 to 30). The ratio of [CO] / [CH ₃ OH]> 0.6 and the ratio of [CO] / [CH ₃ OH] in the range of 0.5 to 10.0 in terms of molar ratio of carbon monoxide and methanol as reactants improved the reaction rate and the selectivity of acetic acid May be more preferable in view of the above. In addition, carbon monoxide was adjusted by the molar ratio of CO: N ₂ = 90: 10 to the internal standard nitrogen gas. The carbonylation reaction may be carried out at a reaction temperature of 50 ° C to 200 ° C and a reaction pressure of 10 to 70 bar in view of improving the reaction rate and improving the selectivity of acetic acid.

Another aspect of the present invention provides acetic acid prepared by the process according to the third aspect. That is, acetic acid prepared from the carbonylation reaction of ethanol and a carbon monoxide-containing gas is provided.

The present invention can produce a heterogeneous catalyst prepared by using carbon nitride as a support and immobilizing palladium on a carbon nitride network based on rhodium as a known active material, The rhodium and palladium are physically immobilized on the abundant carbon nitride support so as to increase the dispersibility of the catalytically active material and the interaction of rhodium and palladium to reduce the amount of rhodium supported in the support, And the inactivation of the catalyst due to the phenomenon and the self-agglomeration of the rhodium element is suppressed, thereby enhancing the stability of the catalyst and securing the performance of the catalyst over a long period of time.

Also -gC Rh (x) Pd (5 -x) according to the invention ₃ N ₄ The catalysts provide a catalyst having a high selectivity for acetic acid as well as high conversion of methanol in the acetic acid reaction using methanol and carbon dioxide. In addition, since the catalyst can be separated and recovered through a simple separation process such as filtration, methanol and carbon monoxide The efficiency of the process using the carbonylation reaction for synthesizing acetic acid can be greatly improved.

1 is a graph showing the yield of acetic acid when a catalyst according to an embodiment of the present invention and a comparative example is used.
FIG. 2 is a TEM photograph of Rh (1.25) Pd (3.75) -gC ₃ N ₄ catalyst of Example 1 of the present invention in which rhodium and palladium metal are dispersed in a carbon nitride support structure.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the following examples are intended to illustrate the present invention, and the scope of application of the present invention is not limited to these examples.

Example 1. Rh (1.25) Pd (3.75) -g-C ₃ N ₄  Preparation of heterogeneous catalyst

2.850 g of powdered melamine was mixed with 100 ml of distilled water and 1.0529 g of a solution in which 10% by weight of rhodium nitrate (Rh (NO ₃ ) ₂ ) was dissolved in 5% by weight of nitric acid and 395 g of palladium metal 0.2897 g of powdery form of palladium nitrate (Pd (NO ₃ ) ₂ ) in the form of powder is added and stirred at a rate of 180 rpm under a constant temperature bath maintained at 60 ° C. After stirring for 2 hours, it is dried under reduced pressure. The solution having undergone reduced pressure drying was introduced into a circulating dryer at 80 캜 and dried for 12 hours or more to obtain a melamine, rhodium nitrate, palladium nitrate precursor in the form of ocher powder.

The precursor was introduced into a tubular reactor, and a heating reaction was carried out while flowing nitrogen gas at a flow rate of 50 ml / min. The temperature was raised from room temperature to 250 ° C. at a heating rate of 1.9 ° C./min for 30 minutes and then maintained at 250 ° C. for 30 minutes. After the temperature was raised from 250 ° C. to 350 ° C. at a heating rate of 1.7 ° C./minute, For 30 minutes. Thereafter, the temperature was raised from 350 ° C to 550 ° C at a temperature raising rate of 3.3 ° C / minute, and then maintained at 550 ° C for 240 minutes. As a result of the slow carburization method, a rhodium palladium carbon nitride catalyst having a rhodium metal content of 1.25% by weight, a palladium metal content of 3.75% by weight and a specific surface area of 12.3 m ² / g was produced in the form of a deep ocher- (1.25) Pd (3.75) -gC ₃ N ₄ , respectively.

Example  2. Rh (2.5) Pd (2.5) -g- C ₃ N ₄  Preparation of heterogeneous catalyst

A heterogeneous catalyst was prepared in the same manner as in Example 1 except that the rhodium nitrate used in Example 1 was changed to 2.106 g and the palladium nitrate was changed to 0.1923 g to prepare a rhodium metal and palladium A catalyst having a metal content of 2.5 wt% and a specific surface area of 11.3 m ² / g was prepared. The catalyst prepared by the method of Example 2 was designated Rh (2.5) Pd (2.5) -gC ₃ N ₄ .

Example  3. Rh (3.75) Pd (1.25) -g- C ₃ N ₄  Preparation of heterogeneous catalyst

A heterogeneous catalyst was prepared in the same manner as in Example 1 except that the amount of rhodium metal used was changed to 3.159 g and that of palladium nitrate used in Example 1 was changed to 0.0974 g, Of 3.75% by weight, a palladium metal content of 1.25% by weight, and a specific surface area of 6.5 m ² / g. The catalyst prepared by the method of Example 3 was designated Rh (3.75) Pd (1.25) -gC ₃ N ₄ .

Comparative Example  One. Rh (2.5) Ir (2.5) -g- C ₃ N ₄  Preparation of heterogeneous catalyst

A heterogeneous catalyst was prepared in the same manner as in Example 1 except that 0.116 g of iridium chloride (IrCl ₃ ) was added as an iridium precursor instead of palladium nitrate which was always used in Example 1 to prepare a rhodium metal and an iridium metal Of 2.5 wt% and a specific surface area of 12.3 m ² / g, respectively. The catalyst prepared by the method of Comparative Example 1 was designated Rh (2.5) Ir (2.5) -gC ₃ N ₄ .

Comparative Example  2. Rh (2.5) Pt (2.5) -g- C ₃ N ₄  Preparation of heterogeneous catalyst

A heterogeneous catalyst was prepared in the same manner as in Example 1 except that 0.149 g of tetraamine platinum nitrate (Pt (NH ₃ ) ₄ (NO ₃ ) ₂ ) was added as a platinum precursor in place of the palladium nitrate used in Example 1 To prepare a catalyst having a content of rhodium metal and platinum metal of 2.5 wt% based on the total weight of the heterogeneous catalyst. The catalyst prepared by the method of Comparative Example 2 was designated as Rh (2.5) Pt (2.5) -gC ₃ N ₄ .

Comparative Example  3. Rh (2.5) Cu (2.5) -g- C ₃ N ₄  Preparation of heterogeneous catalyst

A heterogeneous catalyst was prepared in the same manner as in Example 1 except that the palladium nitrate as the metal precursor used in Example 1 was changed to 0.288 g of copper carbonate (Cu (NO ₃ ) ₂ 3H ₂ O) A catalyst having a specific surface area of 5.8 m ² / g and a content of rhodium metal and copper metal of 2.5 wt% was prepared. The catalyst prepared by the method of Comparative Example 3 was designated as Rh (2.5) Cu (2.5) -gC ₃ N ₄ .

Comparative Example  4. Rh (2.5) Fe (2.5) -g- C ₃ N ₄  Preparation of heterogeneous catalyst

A heterogeneous catalyst was prepared in the same manner as in Example 1 except that the palladium nitrate as the metal precursor used in Example 1 was changed to 0.551 g of iron nitrate nonanal hydrate (Fe (NO ₃ ) ₃ 9H ₂ O) To prepare a catalyst having a specific surface area of 4.5 m ² / g and a content of rhodium metal and iron metal of 2.5 wt%, respectively, based on the weight of the heterogeneous catalyst. The catalyst prepared by the method of Comparative Example 4 was designated as Rh (2.5) Fe (2.5) -gC ₃ N ₄ .

Experimental Example . Production of Acetic Acid by Carbonylation of Methanol

Carbonylation reactions of methanol and carbon monoxide to acetic acid using the heterogeneous catalysts prepared in Examples 1 to 3 and Comparative Examples 1 to 4 were carried out in a 125 ml batch type autoclave equipped with a Pyrex vessel ). 8 ml of methanol, 10 ml of reaction co-catalyst iodomethane, 2 ml of distilled water and 0.1 g of the prepared heterogeneous catalyst were used as the reactants used in the carbonylation reaction. In order to prepare the atmosphere of reaction proceeding at high pressure, carbon monoxide as a reactant was injected up to 40 bar in the form of a mixed gas of 90: 10 at a molar ratio with nitrogen as an internal standard substance to prepare a reaction. Thereafter, the reactants and the cocatalyst were stirred at a rate of 100 rpm and the temperature was raised until the internal temperature of the reactor reached 135 ° C. After the internal temperature of the reactor reached 135 ° C, which was the reaction temperature, Was raised to 300 rpm and the carbonylation reaction was carried out for 3 hours. The above reaction was carried out in the same manner as in Example 1, except that the methanol conversion rate and the product selectivity were calculated by taking samples at 3 hours after the start of the reaction, in which the conversion of methanol as the reactant was stabilized at a certain level.

division catalyst Methanol
Conversion Rate
(Carbon mole%) Selectivity (mol%) Acetic acid yield ^{2 )}
(mole%) Acetic acid Methyl acetate Others ^{1 )} Example 1 Rh (1.25) Pd (3.75) -gC 3 N 4 99.9 93.4 6.6 - 93.3 Example 2 Rh (2.5) Pd (2.5) -gC 3 N 4 99.9 85.7 14.3 - 85.6 Example 3 Rh (3.75) Pd (1.25) -gC 3 N 4 99.9 90.8 9.4 - 90.7 Comparative Example 1 Rh (2.5) Ir (2.5) -gC 3 N 4 98.7 54.0 46.0 - 53.3 Comparative Example 2 Rh (2.5) Pt (2.5) -gC 3 N 4 98.5 58.9 40.4 0.6 58.0 Comparative Example 3 Rh (2.5) Cu (2.5) -gC 3 N 4 69.1 24.8 64.4 10.8 17.2 Comparative Example 4 Rh (2.5) Fe (2.5) -gC 3 N 4 99.5 76.8 23.2 - 76.5 1) Other: analyzed as acetaldehyde and acetone
2) Yield = (methanol conversion) * (acetic acid selectivity)

As shown in Table 1 above, the catalysts of Examples 1 to 3 are rhodium and palladium carbonitrides, which are heterogeneous catalysts proposed in the present invention, in which the amounts of rhodium and palladium elements located in the support are 1.25 - It was confirmed that the conversion of methanol as the reactant reached 99.9 carbon mole% and the selectivity of acetic acid was 85.7 mol% or more with the catalyst immobilized at 3.75 wt%, and thus the catalytic activity was excellent.

On the other hand, in the case of Comparative Examples 1 to 4 in which the palladium element was replaced with iridium, platinum, copper and iron elements and immobilized on the carbon nitride network at 2.5 wt% based on the total weight of the support, palladium of the same weight The activity of the catalyst of Example 2 was compared with that of the catalyst of Example 2. As a result, it was confirmed that the selectivity to acetic acid was very low. In addition, it was confirmed that the catalyst of Example 1 proposed in the present invention contained rhodium elements of a smaller weight than the catalysts of Comparative Examples 1 to 4, but had much higher selectivity to acetic acid.

FIG. 1 is a graph showing the selectivity of acetic acid according to the content of carbon nitride in the rhodium element and the yield of acetic acid in the heterogeneous catalytic reaction including the metals other than palladium in the carbon nitride support in the rhodium palladium carbonitride heterogeneous catalyst reaction Respectively. As shown in Figure 1, it was placed with the inside of the carbon nitride with 1.25 ~ 3.75 wt.% Rhodium and palladium respectively, rhodium palladium carbon nitride, a heterogeneous catalyst is _{RhIr-gC 3 N 4, RhPt} -gC 3 N 4, RhCu -GC ₃ N ₄ , and RhFe-gC ₃ N ₄ heterogeneous catalysts.

Claims (16)

An alcohol carbonylation catalyst, wherein the catalyst contains a carbon nitride support and rhodium and palladium, and wherein the rhodium and palladium are dispersed within the carbon nitride network.
The method according to claim 1,
Wherein the carbon nitride support has a specific surface area of 0.5 m ² / g to 100 m ² / g, and is a porous structure.
The method according to claim 1,
Wherein the total content of rhodium and palladium is 0.2 wt% to 10 wt% based on the weight of the carbon nitride support.
The method according to claim 1,
Wherein the carbon nitride support is at least one kind selected from the group consisting of graphitic carbon nitride,? -Carbon nitride,? -Carbon nitride, cubic carbon nitride and pseudocubic carbon nitride; catalyst.
The method according to claim 1,
The ratio of the contents of rhodium and palladium is a heterogeneous catalyst wherein palladium is 5-X when rhodium is X, wherein X is a positive number of 0.1 to 4.9.
The method according to claim 1,
Wherein the alcohol is methanol or ethanol.
A melamine resin is used as a carbon source, and a rhodium precursor and a palladium precursor are used for heat treatment at a temperature of 500 ° C to 550 ° C under a nitrogen atmosphere to cure the surface. Carbon nitride containing rhodium and palladium Preparing a support, wherein the rhodium and palladium are dispersed and positioned within the network of carbonitrides.
8. The method of claim 7,
Wherein the rhodium precursor is at least one selected from the group consisting of rhodium chloride, rhodium nitrate, dichlorotetracarbonyl di rhodium, acetylacetonato dicarbonyl rhodium, acetylacetone isobothylenium rhodium and dicarbonylpentamethyl cyclopentadienyl rhodium. Gt;
8. The method of claim 7,
Wherein the palladium precursor is at least one selected from the group consisting of palladium chloride, palladium nitrate, sodium tetrachloropalladate, potassium tetrachloropalladate, and palladium chloride.
8. The method of claim 7,
Wherein the carbon nitride support has a specific surface area of 0.5 m ² / g to 100 m ² / g, and a porous structure.
8. The method of claim 7,
Wherein the melamine resin is in powder form.
8. The method of claim 7,
Wherein the mixed solution in which the melamine resin, the rhodium precursor, and the palladium precursor are dissolved is used as the method for producing the heterogeneous catalyst.
6. A process for producing a catalyst comprising the steps of: introducing a carbon monoxide-containing gas into a methanol-containing solution at a pressure of 10 bar to 200 bar in the presence of the heterogeneous catalyst according to any one of claims 1 to 6, A process for the production of acetic acid which carbonylates methanol with carbon monoxide.
14. The method of claim 13,
Wherein the methanol-containing solution contains methanol as a reactant and iodomethane and water as a cocatalyst.
15. The method of claim 14,
Wherein the mixing ratio of methanol: iodomethane: water is 10 to 80:10 to 60:10 to 30 by weight.
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