KR101436429B1 - The method of cyclic-hydrocarbon production using supported noble metal catalysts from lignin-derivatives - Google Patents

Abstract

The present invention relates to a catalyst for the production of cyclic hydrocarbons represented by the following general formula (1) or (2), and a process for producing cyclic hydrocarbons from a lignin conversion material through hydrogen deoxygenation and hydrogenation using the same.
[Chemical Formula 1]
M / MoO _x / y-Al ₂ O ₃
(2)
M / WO _x / y-Al ₂ O ₃
M is Pd, Pt, Ru or Rh.

Description

The present invention relates to a method for producing cyclic hydrocarbons from a lignin conversion material using a noble metal-supported catalyst,

The present invention relates to a process for the production of cyclic hydrocarbons from a lignin conversion material using a noble metal-supported catalyst.

In recent years, due to the limited reserves of fossil fuels, biomass has attracted attention as a feedstock for not only fuels but also organic chemicals. Among them, lignin is a by-product produced in the pulp process and is used again as a low-grade fuel. Lignin is usually converted to gas or liquid by pyrolysis and used as fuel or feedstock. Liquid phase is called "bio-oil" and is an aromatic compound containing about 40% oxygen. consist of.

Therefore, in order to use bio oil as a raw material for supplying a chemical, it is important to properly remove oxygen contained in bio oil. In recent years, hydrodeoxygenation using a catalyst has been carried out because of its high utilization value because the oxygen of the lignin converting material can be appropriately removed and converted into an aromatic chemical having a high yield.

U.S. Patent No. 4,647,704 describes a method of converting lignin to an aromatic phenol through a hydrogen deoxygenation reaction. Here, the catalyst is a zerovalent or sulfide tungsten-based catalyst, nickel is used as an additive, and silica-alumina or silica-alumina-phosphate is used as a carrier. Korean Patent Registration No. 10-0587248 discloses that tungsten or molybdenum catalysts include phosphorus, nickel, cobalt, iron, ruthenium and the like, or cobalt, palladium, nickel and platinum catalysts include zinc, rhenium, selenium, tin, germanium, Lt; RTI ID = 0.0 > benzene < / RTI >

The addition of hydrogen in the deoxygenation reaction causes the sulfide catalyst to become active. Therefore, in the prior art, a method of converting a guaiacol to an aromatic compound such as phenol and benzene by using a lignin model material, Guaiacol, as a reactant, and a sulfide catalyst, was discussed. In particular, sulfide molybdenum-based catalysts can produce aromatic compounds such as phenol and benzene through hydrogenation deoxygenation reaction. Therefore, it is possible to produce aromatic compounds such as CoMo or NiMo / Al ₂ O ₃ , Were investigated.

The guaiacol is converted into an aromatic chemical through successive reactions in the presence of hydrogen and a sulfide catalyst as shown in the following reaction scheme 1, and the benzene ring is hydrogenated and converted to cyclohexane.

[Reaction Scheme 1]

However, recent studies have shown that sulfur from the sulfide catalysts not only deactivates the catalyst but also contaminates the product and requires high temperature and pressure conditions. Therefore, in order to solve this problem, a catalyst which does not require sulfur treatment under relatively simple conditions Precious metal catalysts are being studied. Unlike the sulfide catalyst, the noble metal catalyst first hydrogenates the benzene ring of the guaiacol and converts it into cyclohexane through the hydrogen deoxygenation reaction as shown in the following reaction formula (2).

[Reaction Scheme 2]

U.S. Pat. No. 4,647,704 Korean Patent No. 10-0587248

E. Laurent et al. Applied Catalysis A: General vol. 109, 1994, p.77-96, p. 97-115 A. Gutierrez et al., Catal. Today vol. 147, 2009, p.239-246] C. Zhao et al., J. Catal. vol. 280, 2011, p.8-16 C.R. Lee et al., Catal. Commun. vol. 17, 2012, p.54-58

(Pd, Pt, Ru, or Rh) containing gamma-alumina as a carrier to obtain cyclic hydrocarbons produced by hydrogen deoxidation and hydrogenation from a lignin conversion material containing an aromatic hydrocarbon in high yield, Containing tungsten oxide or molybdenum oxide-based catalyst.

It is another object of the present invention to provide a method for producing cyclic hydrocarbons from a lignin conversion material using the catalyst.

In order to achieve the above object,

The present invention provides a cyclic hydrocarbon-producing catalyst represented by the following general formula (1) or (2).

[Chemical Formula 1]

M / MoO _x / y-Al ₂ O ₃

(2)

M / WO _x / y-Al ₂ O ₃

M is Pd, Pt, Ru or Rh.

The present invention also provides a method for producing an annular hydrocarbon from a lignin converting material using the catalyst.

The catalyst of the present invention makes it possible to produce cyclic hydrocarbons from lignin conversion materials in high yields and can be used without sulfur treatment to produce cyclic hydrocarbons under relatively simple conditions without contamination of the product.

1 is a graph showing the conversion of guaiacol according to the type of catalyst.
2 is a graph showing the production rate of cyclic hydrocarbons converted from guaiacol according to the amount of tungsten added.
FIG. 3 is a graph showing the results of repeated measurements ten times in order to examine the durability of the catalyst of the present invention.
FIG. 4 is a graph showing the production rates of cyclic hydrocarbons when the catalyst of the present invention is used with lignin conversion materials, guaiacol, anisole, catechol, and phenol as reactants.

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

The present invention relates to a catalyst for producing cyclic hydrocarbons represented by the following general formula (1) or (2).

[Chemical Formula 1]

M / MoO _x / y-Al ₂ O ₃

(2)

M / WO _x / y-Al ₂ O ₃

M is Pd, Pt, Ru or Rh.

The catalyst for producing cyclic hydrocarbons according to the present invention is a molybdenum oxide or tungsten oxide catalyst containing a Group VIII noble metal (Pd, Pt, Ru or Rh) containing gamma-alumina as a carrier. The catalyst uses an lignin conversion material as a reactant to produce cyclic hydrocarbons.

The catalyst for producing cyclic hydrocarbons according to the present invention uses alumina having a gamma phase as a carrier and molybdenum oxide (MoO _x ) or tungsten oxide (WO _x ) is preferably added to the alumina support in an amount of 10 to 45 By weight. The molybdenum oxide or tungsten oxide contained in the alumina support is referred to as molybdenum oxide alumina or tungsten oxide alumina, and is represented by the following formula (3) or (4).

(3)

MoO _x / y-Al ₂ O ₃

[Chemical Formula 4]

WO _x / y-Al ₂ O ₃

In addition, the Group VIII noble metal (Pd, Pt, Ru or Rh) is contained in an amount of 1 to 5% by weight based on the weight of the formula (3) or (4).

The present invention relates to a process for producing cyclic hydrocarbons from a lignin conversion material using a cyclic hydrocarbon-forming catalyst represented by the above formula (1) or (2). The lignin conversion material is converted to cyclic hydrocarbons through hydrocracking and hydrogenation.

Examples of the lignin-converting material include guaiacol, anisole, catechol and phenol, and most preferably guaiacol. The guaiacol may be dissolved in an organic solvent, and n-hexane, n-decane and para-xylene are preferable.

The cyclic hydrocarbon-forming catalyst of Formula 1 or Formula 2 is charged into a batch reactor using guaiacol as a reactant, and the reaction is carried out at a temperature of 200 to 400 ° C. and a pressure of 5 to 10 MPa for 1 to 3 hours . Through the above reaction, guaiacol is mainly converted to cyclohexane, and also converted to cyclohexanol and methoxycyclohexanol.

Hereinafter, the present invention will be described in detail by way of examples. However, the following examples are presented to explain the present invention more clearly, and are not intended to limit the scope of the present invention.

< Pd / WO _x / γ- Al ₂ O ₃  ( PdWA ) Catalyst Preparation>

Example  One. Pd10WA  Catalyst preparation

Ammonium metatungstate (Sigma Aldrich) of 10 wt% based on the weight of the alumina carrier was added to the alumina support by an incipient wetness method and then dried at 80 DEG C for 12 hours. Firing the dried material at 500 ℃ to obtain a tungsten-alumina in powder form _{(WO x / γ-Al 2} O 3, 10WA). Thereafter, the pore volume of tungsten alumina was measured and 2 wt% of palladium was added to the tungsten alumina weight by an initial wetting method. At this time, palladium is added in the form of an aqueous solution of palladium nitrate. After that, by firing at 500 ℃ to prepare a _{Pd / WO x / γ-Al} 2 O 3 (Pd10WA) catalyst.

Example  2. Pd20WA  Catalyst preparation

A Pd / WO _x / y-Al ₂ O ₃ (Pd 20WA) catalyst was prepared in the same manner as in Example 1, except that 20 wt% of ammonium metatungstate was added to the alumina support.

Example  3. Pd35WA  Catalyst preparation

Pd / WO _x / y-Al ₂ O ₃ (Pd 35WA) catalyst was prepared in the same manner as in Example 1, except that 35 wt% ammonium metatungstate was added to the alumina support.

Comparative Example  One. WO _x  / γ- Al ₂ O ₃ (35 WA ) Catalyst preparation

Ammonium metatungstate (Sigma Aldrich) at 35 wt% based on the weight of alumina carrier was added to the alumina support by an incipient wetness method and then dried at 80 캜 for 12 hours. The dried material was calcined at 500 캜 to obtain powdery tungsten alumina (WO _x / y-Al ₂ O ₃ , 35WA).

Comparative Example  2. Pd / γ- Al ₂ O ₃ ( PdAl ) Catalyst preparation

A Pd / γ-Al ₂ O ₃ (PdAl) catalyst was prepared by adding an aqueous solution of palladium nitrate of 2 wt% based on the weight of alumina carrier by an initial wetting method and calcining at 500 ° C.

Comparative Example  3. CoMo -S catalyst production

5% by volume of CoMo (Criterion) catalyst was injected with H ₂ S / H ₂ gas and reacted at 400 ° C for 3 hours to prepare a CoMo-S catalyst.

Comparative Example  4. SiO ₂ - Al ₂ O ₃  ( Si - Al ) Catalyst preparation

Silicon precursor tetraethyl ortho silicate _{(Si (OC 2 H 5)} 4, Sigma Aldrich) was prepared with a solution tailored to pH 2.0 using a nitric acid solution after mixing the deionized water. Further, a solution was prepared by mixing aluminum precursor (Al (NO ₃ ) ₃ ? 9H ₂ O, Sigma Aldrich) and tertiary distilled water. The two solutions were mixed and stirred at 40 占 폚 for 1 hour. To this solution was added ammonium hydroxide (NH ₄ OH) dropwise to adjust the pH to 8.5 and aging at 40 ° C for 1 hour. The solid product was filtered and the remaining ammonium nitrate was washed away with tertiary distilled water. And washed once more with ethanol to form a solid having a pore structure. And to the filtered solid was dried at 80 ℃ for 10 hours, calcined at 550 ℃ for 3 hours to prepare a _{SiO 2 -Al 2 O 3 (Si} -Al) catalyst.

Experimental Example  One. Gui Aicol's  Conversion and yield of cyclic hydrocarbons

Alumina catalysts (? -Al ₂ O ₃ , Al) and CoMo catalysts were added to a solution of 3 wt% of guaiacol in an n-decane solvent and 0.5 wt% g to make the total volume to 50 mL to prepare each solution. Each solution was charged with hydrogen gas at 300 ° C. and maintained at a total pressure of 7 MPa for 3 hours to produce cyclohexane from guaiacol through hydrocracking and hydrogenation.

The conversion of guaiacol was calculated from the following equation (1), and the yield of cyclohexane of guaiacol was calculated from the following equation (2).

[Equation 1]

&Quot; (2) &quot;

The catalysts of Example 3 (Pd35WA) and Comparative Examples 2 (PdAl) to 3 (CoMo-S) of the present invention were converted to other materials by 90% or more. In addition, the catalyst (35WA), alumina catalyst (Al), and CoMo catalyst of Comparative Example 1 showed a conversion rate of 50% or more and a conversion of less than 5% when the catalyst was not added.

However, the conversion to cyclic hydrocarbon cyclohexane was highest at about 90% in Example 3 (Pd35WA), which is the catalyst of the present invention, and was about 60% lower in the catalyst of Comparative Example 2 (PdAl) It looked. Further, no conversion to cyclohexane was observed in other catalysts (Comparative Example 1, Comparative Example 3, alumina catalyst and CoMo catalyst), and the conversion of the guaiacol to aromatic hydrocarbons such as catechol, anisole, phenol and cresol (Fig. 1).

Further, in order to investigate the production rates of cyclic hydrocarbons converted from guaiacol according to the amount of tungsten contained in the catalyst of the present invention, the catalysts of Examples 1 to 3 (Pd10WA, Pd20WA and Pd35WA) containing tungsten and Comparative Example 2 (PdAl) and the catalyst of Comparative Example 4 (Si-Al).

In this experiment, it was confirmed that 100% conversion of guaiacol was observed. Among them, the catalyst (Pd35WA) of Example 3 containing 35 wt% of tungsten most produced cyclohexane, which is a cyclic hydrocarbon, and the catalysts of Example 1 (Pd10WA) and 2 (Pd20WA) containing tungsten in an amount of 10 and 20 wt% Showed a yield of 60% or more. However, the yield of cyclohexane was low in the catalyst of Comparative Example 4 (Si-Al), and the catalyst (PdAl) of Comparative Example 2 not containing tungsten had a lower yield than the catalyst of Examples 1 to 3 of the present invention (Fig. 2).

Experimental Example  2. Measurement of durability of cyclic hydrocarbon-forming catalyst

Using the catalyst (Pd35WA) prepared in Example 3, a reaction solution was prepared in the same manner as in Experimental Example 1 above. In order to measure the durability of the catalyst of the present invention, the yield of cyclohexane converted from guaiacol was measured by reusing the catalyst 10 times.

As a result of repeated ten experiments, the yield of cyclohexane was reduced by less than about 5% (FIG. 3). Therefore, the durability of the cyclic hydrocarbon-producing catalyst of the present invention can be confirmed through experiments.

Experimental Example  3. Yield of cyclic hydrocarbons from various lignin conversion materials

In addition to the lignin conversion substance guaiacol, the yields of cyclohexane, an annular hydrocarbon, were observed using anisole, catechol, and phenol, which are intermediates in the decomposition process of guaiacol.

A solution was prepared in the same manner as in Experimental Example 1 except that the reaction materials were anisole, catechol and phenol. The catalysts were prepared by using the catalyst (Pd35WA) of Example 3 of the present invention, The yield of cyclohexane was observed.

In the experiment using anisol, the anisole was not 100% converted, and all the other substances were 100% converted. In addition, it was confirmed that all of the four materials showed a high yield of cyclohexane of 70% or more (FIG. 4).

Accordingly, it was found that the cyclic hydrocarbon-producing catalyst of the present invention produced cyclic hydrocarbons in a high yield from various lignin conversion materials in addition to guaiacol.

Claims (6)

A catalyst for the production of cyclic hydrocarbons represented by the following general formula (1) or (2), characterized by using a lignin converting material as a reactant.
[Chemical Formula 1]
M / MoO _x / y-Al ₂ O ₃
(2)
M / WO _x / y-Al ₂ O ₃
M is Pd, Pt, Ru or Rh,
Wherein x is 3. The cyclic hydrocarbon-producing catalyst according to claim 1, wherein the molybdenum oxide (MoO _x ) or tungsten oxide (WO _x ) is contained in an amount of 10 to 45 wt% based on the weight of the alumina support. The cyclic hydrocarbon-producing catalyst according to claim 1, wherein M is 1 to 5% by weight based on the weight of the following formula (3) or (4).
(3)
MoO _x / y-Al ₂ O ₃
[Chemical Formula 4]
WO _x / y-Al ₂ O ₃
Wherein x is 3. delete A process for the production of cyclic hydrocarbons from lignin conversion materials using the catalyst of claim 1. The cyclic hydrocarbon according to claim 5, wherein the cyclic hydrocarbon is produced by reacting at a reaction temperature of 200 to 400 ° C and a total pressure of 5 to 10 MPa for 1 to 3 hours. .

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