KR101336981B1 - The method of aromatic compounds production using tungsten oxide titania catalyst for hydrodeoxygenation of Guaiacol - Google Patents

Abstract

The present invention relates to a titania catalyst loaded with tungsten oxide for hydrodeoxygenation of a lignin converting material including guaiacol. More specifically, the present invention relates to a hydrodeoxygenation process through reduction-sulfurization of tungsten oxide supported on titania and changes in promoters, which have not been reported to be used as a non-molybdenum hydrodeoxygenation catalyst. The tungsten titania catalyst prepared according to the present invention can convert guoacol into aromatic chemicals such as phenol. In particular, the anatase catalyst had a higher phenol yield than rutile, and cobalt showed a higher phenol yield. As described above, the nickel or cobalt-supported tungsten titania catalyst of the present invention improved the hydrodeoxygenation reaction by changing the titania structure and the cocatalyst during the preparation process. In particular, the conversion to phenol later than before sulfiding showed good performance.

Description

The method of aromatic compounds production using tungsten oxide titania catalyst for hydrodeoxygenation of Guaiacol}

The present invention relates to a titania catalyst loaded with tungsten oxide for hydrodeoxygenation of a lignin converting material including guaiacol. More specifically, the present invention relates to a hydrodeoxygenation process through reduction-sulfurization of tungsten oxide supported on titania and changes in promoters, which have not been reported to be used as a non-molybdenum hydrodeoxygenation catalyst.

Recently, due to the limited reserves of fossil fuels, biomass has been spotlighted as a feedstock of organic chemicals as well as fuels. Among them, lignin is now a by-product of the pulp process and is burned and used as a lower fuel. In general, lignin is converted into gaseous or liquid phase through pyrolysis to be used as fuel or feedstock. In the case of liquid phase, it is called bio-oil and is composed of aromatic compounds containing high oxygen (about 40%). have.

Therefore, it is important to properly remove oxygen contained in bio oil in order to use it as a feedstock for chemicals. Recently, hydrogenated deoxygenation (catalyst) using a catalyst can be converted into a high yield of aromatic chemicals by appropriately removing oxygen from a lignin converting material, and thus many studies have been conducted.

For example, Korean Patent Publication No. 2010-0074025 describes a method for converting a renewable source derived charge through a deoxygenation reaction. In this case, a sulfide molybdenum-based catalyst is used, and the alumina support includes a doping element selected from phosphorus, boron, and silicon. The method is carried out at a temperature of 120-450 ° C., a pressure of 1-10 MPa and a time-space velocity condition of 0.1-10 h ⁻¹ .

In addition, Korean Patent Laid-Open Publication No. 2008-0012831 discloses a step of hydrodeoxygenating and hydroisomerizing an oil in a single process as a method of preparing a fuel composition from vegetable and / or animal oils, and using a palladium or platinum catalyst. .

In the deoxygenation reaction, the sulfide catalyst is known to be active when hydrogen is added. Various literatures address their possibilities for the catalytic conversion of lignin model material, Guaiacol, into reactants. In particular, E. Laurent et al. Applied Catalysis A: General vol. 109, 1994, p. 77-96, p. 97-115, describe the conversion reaction of guaicol in the presence of sulfur catalyst CoMo or NiMo / Al ₂ O ₃ . The use of sulfide molybdenum-based catalysts makes it possible to produce aromatic chemicals such as phenol and benzene through hydrogenation dehydrogenation.

[Reaction Scheme 1]

The hydrodeoxygenation of guaacol is converted to aromatic chemicals through a continuous reaction as in Scheme 1 above in the presence of hydrogen and a catalyst. The conversion of guaacol to catechol consists of the conversion of the hydroxyl group of the methyl group.

Currently, aromatic chemicals such as catechol, phenol, and benzene are mostly produced from petrochemical raw materials, and since the process is complicated, it is necessary to diversify alternative raw materials and processes. The market is continuing to grow, and further research is needed.

Under these technical backgrounds, the present inventors, unlike previous studies using titanium-based catalysts in titania in the hydrodeoxygenation of feeds derived from renewable sources, differed from the previous studies in the hydrodeoxidation of guaricol, a lignin conversion material containing aromatic carbon. The present invention has been completed in order to produce a high yield of phenol by preparing a tungsten catalyst supported on titania having a different crystal structure in the digestion reaction.

After all, it is an object of the present invention to provide a method for producing aromatic compounds such as catechol and phenol through hydrodeoxygenation of guiacol using a tungsten oxide titania catalyst.

According to an aspect of the present invention, in the hydrodeoxygenation reaction using a catalyst-support, a method for converting a lignin conversion material into an aromatic chemical using a tungsten-based catalyst of 2% by weight to 30% by weight based on the support mass This is provided.

According to one embodiment, the tungsten may be tungsten oxide (WO _X ).

According to one embodiment, the catalyst may further comprise nickel or cobalt as a promoter.

According to one embodiment, the catalyst may contain sulfur through a reduction-sulfurization treatment.

According to one embodiment, the hydrodeoxygenation reaction for converting the lignin conversion material into an aromatic chemical may be carried out at a temperature of 200 ~ 400 ℃, a total pressure of 5 ~ 10 MPa and 1 to 3 hours.

According to one embodiment, the lignin converting material may be guaacol.

The tungsten titania catalyst prepared according to the present invention can convert guoacol into aromatic chemicals such as phenol. In particular, the anatase catalyst had a higher phenol yield than rutile, and cobalt showed a higher phenol yield. As described above, the nickel or cobalt-supported tungsten titania catalyst of the present invention improved the hydrodeoxygenation reaction by changing the titania structure and the cocatalyst during the preparation process. In particular, it can be seen that the conversion to phenol is more excellent after the sulfidation treatment.

1 shows the results of guiacol hydrodeoxygenation of Ni-WT (A), Ni-WT (R), Co-WT (A), and Co-WT (R) catalysts according to the promoter, carrier structure (conversion rate) And C1 yield of the products).
2 shows the guiacol hydrogenation of Ni-WT (A), Ni-WT (R), Co-WT (A), and Co-WT (R) catalysts subjected to reduction-sulfurization treatment according to the promoter and carrier structure. The deoxygenation reaction results (conversion and C1 yield of products) are shown.
Figure 3 shows the reaction test results of the catalyst prepared using alumina as a support.

Definition of Terms

By "lignin convertors" of the present invention is meant all products produced through the chemical treatment of lignin.

The nomenclature of the catalyst prepared in the present invention is shown in Table 1 below.

nomenclature Prepared Catalyst WT (A), WT (R) WO _X / TiO ₂ (Anatase), WOx / TiO ₂ (Rutile) Ni-WT (A), Ni-WT (R) Ni / WO _X / TiO ₂ (Anatase), Ni / WOx / TiO ₂ (Rutile) Co-WT (A), Co-WT (R) Co / WO _X / TiO ₂ (Anatase), Co / WOx / TiO ₂ (Rutile) Ni-WT (A) -S, Ni-WT (R) -S Ni / WO _X / TiO ₂ (Anatase) -S, Ni / WOx / TiO ₂ (Rutile) -S Co-WT (A) -S, Co-WT (R) -S Co / WO _X / TiO ₂ (Anatase) -S, Co / WOx / TiO ₂ (Rutile) -S

The anatase of the present invention is also called anatase. The chemical component is TiO ₂ . It is a component such as rutile (rutile) and pantitanium stone, and is an example of polymorphic phase. Sharp awl, sometimes plate-shaped crystalline. Hardness 5.5-6.0, specific gravity 3.8-3.9. It is usually black, blue or brown. It turns into rutile at a high temperature of 600 ° C. or higher. In addition to igneous rocks, it is also produced among hydrothermal veins.

In addition, the rutile (Rutile) is also called rutile. The chemical composition is TiO ₂ , which is an important raw mineral for titanium. Form a rod or needle shape crystal. There are many twins, and the twin twins, and also the sixth, eighth, and lattice. There are also granular or odd ones. Hardness 6-6.5 and specific gravity 4.2-4.3. The cleavage is incomplete with the rod surface, and the cross section is shell or uneven. Reddish brown, reddish red, magenta, yellowish brown, yellow, etc. are opaque and have strong gold and metallic luster. Streak color is yellowish brown. The difference between anatase and rutile is due to the change of crystal structure according to the phase transition temperature of TiO ₂ , and the difference in crystal structure can be confirmed by X-ray diffraction. It is known to have an anatase phase at low temperatures and to have a rutile structure through phase transition at 700 ° C.

Hereinafter, the present invention will be described in detail.

In order to achieve the above technical problem, the present invention provides a method for converting an aromatic substance such as catechol and phenol using a tungsten catalyst instead of a conventional molybdenum catalyst in the hydrodeoxygenation of guaiacol.

According to an aspect of the present invention, in the hydrodeoxygenation reaction using a catalyst-support, a method for converting a lignin conversion material into an aromatic chemical using a tungsten-based catalyst of 2% by weight to 30% by weight based on the support mass This may be provided.

If the weight of the tungsten-based catalyst is less than 2% by weight relative to the mass of the support, the catalytic reaction does not occur, and it is not preferable.

According to one embodiment, the tungsten may be tungsten oxide (WO _X ).

According to one embodiment, the catalyst may further comprise nickel or cobalt as a promoter.

According to one embodiment, the catalyst may be one containing sulfur through a reduction-sulfurization treatment.

According to one embodiment, the hydrodeoxygenation reaction for converting the lignin conversion material into an aromatic chemical may be carried out for a temperature of 200 ~ 400 ℃, the total pressure 5 ~ 10 MPa and 1 to 3 hours.

According to one embodiment, the lignin converting material may be guaacol.

Titania, which is used as the catalyst carrier of the present invention, is prepared by supporting tungsten, which is an active substance of acid spot expression, by dualizing into anatase and rutile structures. Tungsten titania is a material having a form such as the following formula (1), the reactivity of this reaction varies depending on the structure.

[Formula 1]

WO _X / TiO ₂ (Anatase), WOx / TiO ₂ (Rutile)

When the nickel or cobalt as a promoter is supported on the catalyst, a material having a form as shown in Chemical Formulas 2 and 3 may be prepared.

(2)

Ni / WO _X / TiO ₂ (Anatase), Ni / WO _X / TiO ₂ (Rutile)

(3)

Co / WO _X / TiO ₂ (Anatase), Co / WO _X / TiO ₂ (Rutile)

In addition, the catalysts subjected to reduction-sulfurization treatment on tungsten titania, nickel / tungsten titania, and cobalt / tungsten titania may be represented by the following formulas (4), (5), and (6).

[Chemical Formula 4]

WO _X / TiO ₂ (Anatase) -S, WOx / TiO ₂ (Rutile) -S

[Chemical Formula 5]

Ni / WO _X / TiO ₂ (Anatase) -S, Ni / WO _X / TiO ₂ (Rutile) -S

[Chemical Formula 6]

Co / WO _X / TiO ₂ (Anatase) -S, Co / WO _X / TiO ₂ (Rutile) -S

Hereinafter, the content of the present invention will be described in detail through Examples and Experimental Examples. However, these are intended to explain the present invention in more detail, and the scope of the present invention is not limited thereto.

Titania carrier  And preparation of catalysts

1.tungsten Titania ( WO _X Of TiO ₂ ) Preparation of Catalyst

In the case of titania used as a carrier, rutile and anatase structures were prepared by the sol-gel method, and titanium (IV) isopropoxide was used as a precursor. In the case of the rutile structure, the precursor is added to 2 M hydrochloric acid solution, stirred for 2 days, and the powder material obtained by evaporating the solution is calcined at 500 ° C. for 2 hours to prepare rutile titania. On the other hand, anatase titania was added to the acetyl acetone and the precursor in 0.15 mM sulfuric acid solution and aged for 2 hours at 55 ℃, 10 hours at 90 ℃, the solution was evaporated and the remaining solid was calcined at 500 ℃ for 2 hours Titania (Anatase Titania) is prepared.

The tungsten precursor is prepared by using ammonium metatungstate of Sigma Aldrich from aqueous solution. Titania prepared by the above method was used as a carrier, and 5% by weight of the support was added by an incipient wetness method and dried at 80 ° C. for 12 hours. The dry catalyst was calcined at 500 ° C. to prepare a powdered tungsten titania (WO _X / TiO ₂ ) catalyst. The nomenclature of the prepared catalyst is shown in Table 1 above.

2. Ni Of WO _X Of Al ₂ O ₃  or Co Of WO _X Of Al ₂ O ₃  Preparation of the catalyst

The pore volume of the powdered tungsten titania catalyst prepared in Example 1 was measured and an aqueous solution of 2% by weight of nickel nitrate or cobalt nitrate was added by an initial wet method and calcined at 500 ° C. to obtain Ni / WO _X / Al ₂ O. ₃ or Co / WO _X / Al ₂ O ₃ catalyst was prepared.

3. S- WO _X Of TiO ₂ , S- Ni Of WO _X Of TiO ₂ , S- Co Of WO _X Of TiO ₂  Preparation of the catalyst

S-WO _X / TiO ₂ , S-Ni / WO were subjected to reduction-sulfurization treatment using 5 vol% H ₂ S / H ₂ gas at 400 ° C. for 3 hours at 400 ° C. _X / TiO ₂ , S-Co / WO _X / TiO ₂ catalyst was prepared.

Hereinafter, the catalyst group prepared in 1, 2, 3 may be charged in a batch reactor to perform hydrodeoxygenation of guai alcohol for 150 minutes at 300 ° C. The reactant guaiacol can be used by dissolving in a suitable solvent, and organic solvents such as hexane (n-hexane) and para xylene (p-xylene) are preferable. When hydrodeoxygenation of guaiacol is carried out using the catalyst according to the present invention, catechol, phenol, cresol, trimethylbenzene, benzene, toluene and the like are produced.

Example  One

The catalyst groups prepared in 1, 2, and 3 were applied to hydrodeoxygenation of guaiacol. The total reaction was 50mL, 3% by weight of guaiacol, 2% by weight of pentadecane (pentadecane), a solvent para xylene was used, the experiment was performed by adding 0.5 g of the catalyst. The reaction temperature was 300 ℃, the total pressure was filled with hydrogen gas to maintain 7 MPa, the total reaction time was fixed to 150 minutes. 1 and 2 show the conversion of the guai alcohol and the yield of the products under the above reaction conditions. Conversion rate and yield are derived through the following equations 1, 2.

Comparative Example  One

The reaction was carried out in the same manner as in Example 1, except that 5 wt% of tungsten used as the active species was three times more than the catalyst prepared in Example 1, and the result was illustrated. 3 is shown.

[Formula 1]

[Formula 2]

The tungsten titania catalyst prepared according to the present invention can convert guoacol into aromatic chemicals such as catechol, phenol, benzene and the like. Particularly, the catalysts having a large amount of acid spots had higher yields of products than the other catalyst groups, and the yield change of the catalyst and reduction-sulfurization treatment was also confirmed.

1 shows the results of guiacol hydrodeoxygenation of Ni-WT (A), Ni-WT (R), Co-WT (A), and Co-WT (R) catalysts according to the promoter, carrier structure (conversion rate) And the C1 yield of the products), in the case of the cobalt-supported tungsten titania catalyst (Co-WT (A)), the most hydrodeoxygenation reaction was performed and the yield of phenol and catechol was the highest.

FIG. 2 shows the results of conversion of guiacol hydrodeoxygenation of Ni-WT (A), Ni-WT (R), Co-WT (A), and Co-WT (R) catalysts (reduction rate and product). Yield of C1). As described above, the nickel or cobalt-supported tungsten titania catalyst of the present invention improved the hydrodeoxygenation reaction by changing the structure and cocatalysts (nickel, cobalt) of Titania and sulfiding in the manufacturing process. In particular, the conversion to phenol is particularly improved in the case of sulfidation (FIG. 2) compared to before sulfidation (FIG. 1).

This effect can be seen that the results are significantly superior to the catalyst (control) using the alumina support. 3 shows the reaction test results of the catalyst prepared using alumina as a support. Although the amount of tungsten used as the active species is a catalyst in which 5% by weight of alumina is three times more than the catalyst prepared in Example, it can be seen that the conversion and yield are significantly lower.

The tungsten titania catalyst prepared according to the present invention can convert guoacol into aromatic chemicals such as phenol. In particular, the anatase catalyst had a higher phenol yield than rutile, and cobalt showed a higher phenol yield. As described above, the nickel or cobalt-supported tungsten titania catalyst of the present invention improved the hydrodeoxygenation reaction by changing the titania structure and the cocatalyst during the preparation process. In particular, it can be seen that the conversion to phenol is more excellent after the sulfidation treatment.

While the present invention has been particularly shown and described with reference to specific embodiments thereof, those skilled in the art will appreciate that such specific embodiments are merely preferred embodiments and that the scope of the present invention is not limited thereby. something to do. It is therefore intended that the scope of the invention be defined by the claims appended hereto and their equivalents.

Claims (6)

In the hydrodeoxygenation reaction using the catalyst and the catalyst-support of the support carrying thereon, 2 wt% of tungsten oxide (WO _X ), which is an acid-expressing material, is placed on a titania (TiO ₂ ) support having an anatase or rutile structure. A method of converting guaiacol into at least one aromatic compound selected from the group consisting of benzene, catechol, cresol, trimethylbenzene, phenol and toluene with a catalyst-support prepared by loading to 30% by weight. The method of claim 1 wherein the catalyst further comprises nickel or cobalt as a promoter. The method of claim 1 wherein the catalyst contains sulfur via a reduction-sulfurization treatment. The method according to any one of claims 1 to 3, wherein the hydrodeoxygenation reaction is carried out for a temperature of 200 to 400 ° C, a total pressure of 5 to 10 MPa and for 1 to 3 hours. delete delete

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