KR101535123B1 - Carbon catalyst having open pore in which dispersed metal and method for producing sorbitol using the same - Google Patents

Abstract

The present invention relates to a metal supported carbon catalyst whose structure is open in which metal is dispersed, a manufacturing method thereof and a method for producing sorbitol from cellulose under the catalyst wherein the open structure in the catalyst is allowed to disperse metal, and functional groups bound to the surface of the catalyst are allowed to generate hydrogen spillover, thereby producing sorbitol in a high selectivity and a high yield in a cellulose conversion process with use of the catalyst.

Description

TECHNICAL FIELD The present invention relates to a carbon catalyst having an open pore structure in which metal is dispersed and a method for producing sorbitol using the same.

The present invention relates to a catalyst which can be used for the conversion production of sorbitol from woody biomass raw materials, and a method for producing sorbitol in high yield using the catalyst. In particular, it relates to a method for producing sorbitol in high yield from woody biomass in the presence of a catalyst consisting of a metal dispersed in a carbon carrier having an open pore structure.

Fossil fuels, which have been used as primary energy sources since the 20th century, are now reaching their limits and the need for alternative energy is increasing rapidly. In particular, serious environmental problems caused by the indiscriminate use of fossil fuels are urging the development of sustainable and environmentally friendly renewable energy sources. Biomass is recognized as an environmentally friendly and sustainable energy source as one of the renewable energy sources, and development has been promoted. The first generation of biomass was mainly made of edible materials such as sugar cane, corn and sunflower seed oil, and it has been converted to produce carbohydrates and glucose. However, along with the global hunger problem, there has been a growing negative view on this issue, and therefore, woody biomass materials that are not currently edible are attracting attention as second-generation biomass.

Among woody biomass, cellulose is the most abundant resource. Cellulose is produced by the photosynthetic action of plants and has a high molecular weight, high crystallinity, and insolubility due to the linking of pentoses or hexoses. In order to produce sorbitol from cellulose, a hydrolysis reaction and a hydrogenation reaction must proceed. The hydrolytic reaction that hydrolyzes cellulose is a reaction that breaks the beta-1,4-glycosidic bond of cellulose. The acid catalyst used in the petrochemical process has an effective conversion yield It has not been able to get it, and there is still a limit to practical use. This is due to the aforementioned properties of the cellulose. Therefore, there is a need for a catalyst that not only has acidic properties but also facilitates mass transfer characteristics of a wood-based biomass-derived compound having a large molecular weight.

The present invention provides a catalyst capable of converting sorbitol to cellulose in a high yield and a process for producing the same.

It is another object of the present invention to provide a method for converting and producing sorbitol from cellulose in a high yield.

In order to achieve the object of the present invention, the present invention provides a carbon carrier comprising a carbon nanomaterial having an open pore structure; And a metal-dispersed carbon catalyst comprising a metal dispersed in the carbon support.

According to an embodiment of the present invention, the carbon nanomaterial is preferably spherical.

According to another embodiment of the present invention, it is preferable that the metal is at least one selected from the group consisting of Ru, Pt, Pd, Rh, Al, Mg, Fe, Co, Cu, Ni and Ir.

According to another embodiment of the present invention, the metal is preferably contained in an amount of 0.1 to 10% by weight based on the total weight of the carbon nanomaterial.

The present invention also relates to a method for preparing a phenol-formaldehyde resin solution, comprising the steps of: supporting a silica spheres (DSS) having an open pore structure on a phenol-formaldehyde resin solution; Centrifuging the silica spheres supported on the solution; Removing excess resin from the silica spheres through centrifugation and drying; Aging the dried silica spheres and carbonizing them; And a step of etching, filtering, and drying the carbonized spherical silica spheres, and a carbon nanomaterial having an open pore structure.

According to an embodiment of the present invention, aging is preferably performed at 80 to 110 ° C for 20 to 25 hours.

According to another embodiment of the present invention, the carbonization is preferably carried out at a temperature of 800 to 900 DEG C under a nitrogen atmosphere.

According to another embodiment of the present invention, the etching is preferably performed using hydrogen fluoride or sodium hydroxide for 24 to 30 hours.

The present invention also relates to a method for producing a carbon nanomaterial, comprising: mixing a metal precursor solution in a solution containing a carbon nanomaterial having an open pore structure; Adjusting the pH of the mixed solution to be alkaline; Reducing the metal ions contained in the metal precursor solution; And a method of producing a metal-supported carbon catalyst having an open pore structure in which metal is dispersed by filtration and washing.

According to an embodiment of the present invention, the metal of the metal precursor solution is at least one selected from the group consisting of Ru, Pt, Pd, Rh, Al, Mg, Fe, Co, Cu, Ni and Ir.

According to another embodiment of the present invention, the metal precursor is a platinum precursor, preferably PtH ₂ Cl ₆ .H ₂ O.

According to another embodiment of the present invention, it is preferable to add a sodium hydroxide or ammonium hydroxide solution to the step of controlling the alkalinity.

According to another embodiment of the present invention, the reducing step is preferably added with sodium borohydride or ethylene glycol.

The present invention also provides a process for producing sorbitol comprising hydrolyzing and hydrogenating cellulose in the presence of the metal supported catalyst according to the present invention.

According to one embodiment of the present invention, the step of hydrolyzing and hydrogenating the cellulose is preferably carried out under a hydrogen pressure of 10-100 bar.

According to an embodiment of the present invention, the step of hydrolyzing and hydrogenating cellulose is preferably carried out at 150 to 200 ° C for 12 to 24 hours.

In the case of producing sorbitol by hydrolysis and hydrogenation of cellulose using a carbon catalyst having an open pore structure in which the metal is dispersed in the present invention, sorbitol is produced at a very high yield without using any additional acid treatment or acid catalyst Can be obtained.

In addition, since the catalyst of the present invention can be highly dispersed in the metal due to the open pore structure, a large amount of hydrogen spillover occurs due to a rich functional group bonded to the surface, and a very high selectivity is obtained in the conversion reaction of the cellulose using the catalyst of the present invention Sorbitol can be produced with a yield of tallow.

1 shows TEM and STEM analysis results of the structure of the CNE / Pt catalyst of Example 2 of the present invention.
2 shows the results of TEM analysis of the catalysts of Example 2, Comparative Example 1 and Comparative Example 2 of the present invention.
3 shows XRD analysis results of the catalyst of Example 2, Comparative Example 1 and Comparative Example 2 of the present invention.
4 shows TGA analysis results of the catalysts of Example 2, Comparative Example 1 and Comparative Example 2 of the present invention.
FIG. 5 shows nitrogen isothermal adsorption / desorption distributions as a result of BET analysis of the catalysts of Example 2, Comparative Example 1 and Comparative Example 2 of the present invention.
6 shows pore size distributions as a result of BET analysis of the catalysts of Example 2, Comparative Example 1 and Comparative Example 2 of the present invention.
FIG. 7 shows XRD analysis results of four types of cellulose having different degrees of crystallinity.
Fig. 8 shows the results of analysis of conversion of cellulose and sorbitol yield as a result of carrying out conversion experiment of four types of cellulose having different degrees of crystallinity using the catalysts of Example 2, Comparative Example 1 and Comparative Example 2. Fig.
9 is a graph showing the results of analysis of cellulose conversion and glucose yield with time as a result of carrying out a cellobiose conversion test using a carrier of the catalyst of Example 2, Comparative Example 1 and Comparative Example 2 (in the state of not carrying platinum) , And Example 4, Comparative Example 5 and Comparative Example 6, respectively.
10 shows the hydrogen adsorption / desorption experiment results of the catalyst of Example 2, Comparative Example 1 and Comparative Example 2 of the present invention.
11 is a graph showing the degree of bonding of functional groups on the surface of the catalyst of Example 2, Comparative Example 1 and Comparative Example 2 of the present invention. The results are shown in Table 4, Comparative Example 5, and Comparative Example 6, respectively, by the XPS analysis.
12 shows the results of measurement of CVs of respective catalysts through electrolysis of water in order to examine the degree of hydrogen spillover of the catalyst of Example 2, Comparative Example 1 and Comparative Example 2 of the present invention.

Hereinafter, the present invention will be described in detail with reference to specific embodiments of the present invention, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a schematic diagram of a metal supported catalyst comprising a carbon nanomaterial in the form of dandelion seeds or Echinometra mathaei having open pore structure, Will be described in detail.

The catalyst according to an embodiment of the present invention includes a carrier made of a carbon nanomaterial having an open pore structure (hereinafter also referred to as 'CNE') and a metal supported on the carrier.

In the present invention, "open pore structure" means that the pore size increases from the center of the particle to the outside, and the microporous structure and the mesoporous structure used in the comparative example It is a different concept.

According to an embodiment of the present invention, the carrier may be spherical, which facilitates the implementation of an open pore structure, and also facilitates the implementation of a dandelion seed or a sea urchin shape. The pores of the carrier preferably have mesopores, that is, average pores having a size of 2 to 1000 nm. The catalyst of the present invention can exhibit a high mass transfer effect in the conversion reaction of cellulose to sorbitol, which will be described later, through medium size pores, and as a result, the yield can be improved.

The metal dispersed in the carrier constituting the catalyst of the present invention preferably exhibits a high reaction activity upon conversion of cellulose to sorbitol and can provide high selectivity to sorbitol. Such a metal may be at least one selected from the group consisting of Ru, Pt, Pd, Rh, Al, Mg, Fe, Co, Cu, Ni and Ir. The amount of the metal to be dispersed and carried on the carrier is not particularly limited, but is 0.1 to 10% by weight, preferably 2 to 8% by weight, more preferably 4 to 6% by weight based on the total weight of the catalyst. This is an appropriate range in terms of the reaction yield using the catalyst and the cost-effectiveness.

In the present invention, a carrier made of a carbon nano material having an open pore structure may be prepared by: supporting a Dandelion Silica Sphere (DSS) having an open pore structure on a phenol-formaldehyde resin solution; Centrifuging the silica spheres supported on the phenol-formaldehyde solution; Removing excess resin from the centrifuged silica spheres and drying; Aging the dried silica spheres and carbonizing them; And a step of etching, filtering and drying the carbonized silica spheres.

When the silica spheres are supported on the phenol-aldehyde resin solution, the OH groups of the phenol molecules contained in the phenol-aldehyde resin can be bonded to the surface of the carbon support as a functional group. Therefore, if a metal is supported on the carrier under the pressure of hydrogen which is usually employed to produce sorbitol from cellulose, a large amount of hydrogen spillover phenomenon is caused, and even if no acid catalyst is added, The decomposition reaction can proceed smoothly.

In order to form a carrier having an open pore structure, aging is preferably carried out at 80 to 110 DEG C for 20 to 25 hours. The carbonization of the silicon sphere can be carried out at a temperature of 800 to 900 DEG C under a nitrogen atmosphere so that the metal can be dispersed well between the pores and the surface. The etching can also be carried out using hydrogen fluoride or sodium hydroxide for 24 to 30 hours.

Based on the carbon nanomaterial having the open pore structure thus prepared, the metal-dispersed catalyst of the present invention can be produced. According to an embodiment of the present invention, there is provided a method of manufacturing a carbon nanomaterial, comprising: mixing a metal precursor solution into a solution containing a carbon nanomaterial having an open pore structure; Adjusting the pH of the mixed solution to be alkaline; Reducing the metal ions contained in the metal precursor solution; And filtration and washing to prepare a metal-supported catalyst in which the metal is dispersed.

According to an embodiment of the present invention, the metal in the metal precursor solution may be at least one selected from the group consisting of Ru, Pt, Pd, Rh, Al, Mg, Fe, Co, Cu, have.

To adjust the pH to alkaline, an alkaline compound usually used in this technical field can be added, preferably sodium hydroxide or ammonium hydroxide solution can be added. The pH is not particularly limited as long as the pH is in the alkaline range of pH 8, but it is preferable to adjust the pH to 10 or more, and more preferably to pH 11 or more in order to increase the metal ion retention ratio.

In order to reduce the metal precursor, it is usually possible to add a reducing compound used in this technical field, preferably a compound such as sodium borate (NaBH ₄ ) or ethylene glycol.

According to an embodiment of the present invention, there is also provided a method for preparing a carbon nanomaterial, comprising: mixing a platinum precursor solution into a solution containing a carbon nanomaterial having an open pore structure; Adjusting the pH of the mixed solution to be alkaline; Reducing the platinum ions contained in the platinum precursor solution; Followed by filtration and washing to prepare a catalyst in which platinum is dispersed.

Further, according to one embodiment of the invention, the platinum precursor may be used, _{PtH 2 Cl 6 · H 2 O} .

According to one embodiment of the present invention, a method of converting cellulose into sorbitol comprises hydrolyzing and hydrogenating cellulose in the presence of a metal supported catalyst having a metal dispersed in a carbon carrier having the above-described open pore structure.

In order to produce sorbitol from cellulose, the hydrolysis reaction and the hydrogenation reaction must proceed sequentially. Therefore, for the hydrolysis reaction of cellulose, most of the catalyst processes known hitherto cause hydrolysis reaction using an acid-treated carbon catalyst or an acid catalyst capable of providing H < + >. The CNE-based catalyst according to the present invention can produce sorbitol from cellulose at a high yield even though no additional acid treatment or acid catalyst is used. The present inventors have confirmed that this is due to a hydrogen spillover phenomenon in a carbon carrier having pores of a uniform size and a platinum catalyst under a liquid hydrogen partial pressure described later. The hydrogen spillover phenomenon causes the hydrogen molecules adsorbed on the platinum surface to dissociate into H + and H- in the aqueous solution and move to the carbon support, so that H + can be used as an acid catalyst.

The cellulose conversion reaction may vary depending on the crystallinity of the cellulose. Usually, the smaller the crystallinity, the higher the cellulose conversion. Therefore, in order to improve the conversion ratio in the hydrolysis step, the cellulose may be pulverized to have a decreased crystallinity. The method of pulverizing cellulose is not particularly limited, and for example, ball milling may be used. Cellulose having a reduced crystallinity can be easily brought into contact with the active site of the catalyst, so that the hydrolysis reaction can be smoothly performed, and the conversion of cellulose can be improved.

The step of hydrolyzing and hydrogenating can be carried out under hydrogen pressure of 10-100 bar.

The step of hydrolyzing and hydrogenating may be carried out at a temperature of 150-200 ° C. When the temperature is within the above range, the reaction energy for hydrolysis and hydrogenation is sufficient, and the decomposition of the finally produced sorbitol can be prevented.

Water is supplied for the hydrolysis of cellulose, and the amount of water used is preferably 100 to 10,000 molar ratio with respect to cellulose. When water is supplied in such a range, a sufficient amount of water for hydrolysis can be supplied, the amount of sorbitol produced per unit process can be appropriately adjusted, and a high process economical efficiency can be secured.

The step of hydrolyzing and hydrogenating is not particularly limited, but may be carried out using a batch reactor or a fixed bed reactor.

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

Example

<Analysis equipment>

In the Examples and Comparative Examples of the present invention, the analytical instruments used are as follows.

1. Using TEM: JEOL, JEM-3010

2. STEM: Using HAADF-STEM, Tecnai F20-FEI

3. XRD: Rigaku, D-MAX2500-PC powder using X-ray diffractometer

4. BET: ASAP 2010, using Micromeritics

5. TGA: Using SDT Q600, TA instruments

6. XPS: Using KRATOS, AXIS-HSi

7. TPD: Using Micromeritics Autochem II chemisorption analyzer

< Carrier Manufacturing>

Example  One

0.2 g of silica spheres (DSS) having an open pore structure was mixed with 4 ml of phenol-formaldehyde resin solution, and the mixture was stirred at room temperature for 1 minute. The silica spheres were then centrifuged at 10,000 rpm at 50 &lt; 0 &gt; C. The excess resin was removed from the centrifuged silica spheres and dried. The dried silica spheres were aged at 100 占 폚 for 24 hours and carbonized at a temperature of 90 占 폚 in a nitrogen atmosphere. The carbonized silica spheres were etched for 24 hours using hydrogen fluoride, and then filtered and dried to prepare a carbon nanomaterial-based carrier (CNE) having an open pore structure.

&Lt; Preparation of catalyst &gt;

Example  2

1 g of CNE was added to 100 ml of distilled water and stirred, and 0.108 g of platinum precursor PtH ₂ Cl ₆ .H ₂ O was added. To this solution, 5-7 ml of 0.1 M NaOH solution was added dropwise to adjust the pH to 11. 0.1 M NaBH ₄ , And the mixture was stirred for 3 hours to reduce it to platinum. The sample was filtered and washed three times with distilled water to obtain a catalyst (Pt / CNE) in which platinum was dispersed and supported on a carbon carrier having an open pore structure.

Comparative Example  One

A Pt / AC catalyst was obtained in the same manner as in Example 2, except that activated carbon (AC) having a micropore structure was used as a carrier instead of CNE of the present invention.

Comparative Example  2

A Pt / CMK catalyst was obtained in the same manner as in Example 2, except that a carbon support (CMK) having a medium pore structure was used as a carrier instead of the CNE of the present invention.

TEM and STEM analyzes were performed to observe the structure of the catalyst of Example 2 according to the present invention, and the results are shown in Fig. The Pt / CNE carbon nanomaterial prepared in Example 2 had an open pore structure with a larger pore size from the center of the particle to the outside, and the size of one particle was observed to be about 400 nm in diameter. As a result of STEM-EDS analysis, platinum was highly dispersed on CNE carbon and its size was observed to be fairly uniform, about 5 nm.

The catalysts according to Comparative Example 1 and Comparative Example 2 were also analyzed by TEM, XRD and TGA, and the degree of dispersion, size and amount of catalyst structure and platinum were examined. First, by TEM image analysis, it was confirmed that Comparative Example 1 had a micropore structure and Comparative Example 2 had a medium pore structure. It was confirmed that platinum was highly dispersed in the entire surface of the carbon support as in Example 2 in Comparative Example 1 and Comparative Example 2 as well. FIG. 2 shows TEM analysis results.

The results of the XRD analysis shown in Fig. 3 confirm that platinum is supported on the amorphous carbon in Example 2, Comparative Example 1 and Comparative Example 2. Also, as a result of Scherrer's equation, platinum sizes of 5.4 nm, 5.7 nm, and 4.4 nm, respectively, were about 4-8 nm. . Also, it was confirmed through the TGA analysis that the results are shown in FIG. 4 that the same amount of platinum of 5 wt% was supported on each carbon support in Example 2, Comparative Example 1, and Comparative Example 2.

In order to observe the pore structure of Example 2, Comparative Example 1 and Comparative Example 2 in more detail, BET analysis was performed. FIG. 5 shows the nitrogen isothermal adsorption / desorption distribution, and FIG. 6 shows the pore size distribution. According to the results, in Example 2 and Comparative Example 2, mesopores having a size of 2-5 nm were well developed, whereas in Comparative Example 1, micropores having a size of 1.5 nm were developed.

<Production of sorbitol>

Example  3

A batch system was carried out using 0.4 g of cellulose, 0.4 g of the catalyst of Example 2 and 40 ml of distilled water. The reaction was carried out at 180 ^° C for 24 hours. Sorbitol was produced by continuously stirring and hydrogen pressure of 30 bar.

In this embodiment, the cellulose used in the present invention is a high-performance ball mill made of commercially available cellulose (Avicel) to reduce the crystallinity of the cellulose. The cellulose conversion was determined by using the difference in weight between the solid phase (catalyst and unreacted cellulose) filtered after the reaction at 0.8 g, which is the sum of the weight of the catalyst before the reaction and the weight of the cellulose. In the case of sorbitol yield, the solid phase was filtered through a post-reaction filter, and the remaining liquid was analyzed using a liquid chromatograph instrument (YL9100 Model HPLC and MetaCarb 67C column from Yonglin Co.).

Comparative Example 3 and 4

Sorbitol was converted and produced from cellulose according to Example 3 using the catalysts prepared in Comparative Example 1 and Comparative Example 2, respectively.

Table 1 shows the results of the cellulose conversion reaction of Example 3, Comparative Example 3 and Comparative Example 4.

As a result of conducting the cellulose conversion reaction, the conversion of cellulose was lower than that of Comparative Examples 3 and 4 in Example 3, but the yield of sorbitol was about 21% higher than Comparative Example 3 and 12% higher than Comparative Example 4. The yield of mannitol, which is an isomer of sorbitol, was also higher in Example 3. Finally, the selectivity of hexitol, which is the sum of sorbitol and mannitol, was significantly higher than that of Comparative Examples 3 and 4. The reason why the selectivity of hexitol is high is considered to be that the catalyst of Example 2 used in Example 3 had an open pore structure and mass transfer of the reactant effectively occurred.

An accessibility test was conducted to confirm these estimates.

<Accessibility test>

The accessibility test was divided into cellulosic conversion test and cellobiose conversion test.

First, cellulose conversion experiments were conducted using the catalysts of Comparative Examples 1 and 2 and Example 2 using four types of cellulose having different degrees of crystallinity. The degree of crystallinity (CI) of cellulose was controlled by varying the ball mill treatment time, and the degree of crystallinity of each cellulose was confirmed by X-ray diffraction analysis as shown in FIG.

Fig. 8 shows the result of carrying out the conversion test of four crystals to other cellulose. According to the results, the catalysts of Comparative Example 2 and Example 2 exhibited a similar level of activity, but the catalyst of Comparative Example 1 showed high cellulose conversion. Therefore, it was confirmed that the mesopore structure of mesopores did not exhibit good activity in the case of cellulose conversion having a very high molecular weight. Therefore, it is considered that the conversion reaction of cellulose occurs on the catalyst surface, not in the pores of the catalyst. However, the yield of sorbitol was lowest in the case of using the catalyst of Comparative Example 1 in spite of a high cellulose conversion. This is because, in the case of the intermediate compound produced after the conversion of cellulose, the mesoporous structure This is because it helps to facilitate transmission.

To support this, the hydrolysis reaction was carried out using the disaccharide cellobiose as a reactant. At this time, in order to confirm the difference according to the pore structure of the catalyst, in the catalyst of Example 2, Comparative Example 1 and Comparative Example 2, hydrolysis reaction was carried out using only a carbon carrier as a catalyst without carrying platinum, 4, Comparative Example 5 and Comparative Example 6 are shown in Fig.

As a result, the conversion ratio of Celobiose and the yield of glucose were high in Comparative Example 6 and Example 4 having a mesoporous structure. This means that, in the case of an intermediate compound produced by the conversion of cellulose, when a catalyst having a mesoporous structure is used, an advantageous effect can be obtained over the microporous structure in mass transfer. That is, the first conversion of cellulose, which is a substance having a very large molecular weight and a large molecular size, takes place on the outer surface of the catalyst. Intermediates having a comparatively small size, such as disaccharides, dissolve in water and actively react in the pores to form final compounds such as sorbitol It is to prove to make.

As described above, in order to produce sorbitol from cellulose, the hydrolysis reaction and the hydrogenation reaction must proceed sequentially. Therefore, in most of the conventional catalytic processes for hydrolysis of cellulose, acid catalysts which are acid-treated or acid catalysts capable of providing H + are used, but the catalyst of Example 2 according to the present invention is subjected to additional acid treatment and acid High yield even though the catalyst was not used. This is probably due to the hydrogen spillover phenomenon of the platinum catalyst and the carbon carrier having the uniform size pores under the hydrogen partial pressure in the liquid phase. The hydrogen spillover phenomenon allows the hydrogen molecules adsorbed on the platinum surface to dissociate into H + and H- in the aqueous solution and move to the carbon carrier to use H + as an acid catalyst. In order to confirm this, a spillover phenomenon was observed through experiments of hydrogen desorption and electrolysis of water according to the present invention.

10, it can be seen that the greatest amount of hydrogen was adsorbed in the catalyst of Example 2. As a result of quantitative analysis of the adsorption amount of hydrogen, it was confirmed that 0.342 mmol / g of hydrogen of Example 2 was adsorbed, and 0.275 and 0.257 mmol / g of adsorbed hydrogen of Comparative Examples 1 and 2, respectively. It is believed that this is due to the highest degree of dispersion of platinum in the three-dimensionally open pore structure of the carbon carrier, which is attributed to the uniform size pore structure and the effect of the carbon carrier on the surface rich functional group. Referring to FIG. 11, it can be seen that the largest amount of functional groups are bonded in the carbon support of Example 4. This is due to the influence of the carbon precursor used in the preparation of the carbon support, because the OH of the phenol molecule greatly influences the functional group production of the carbon support by using the phenol-aldehyde resin. Therefore, it is considered that a large amount of hydrogen has a positive effect on the spillover phenomenon when the platinum catalyst is supported.

12 shows the CV measurement results of each catalyst through electrolysis of water. It is reported that the hydrogen spillover phenomenon can be caused by adsorption / desorption of hydrogen gas and also by the splitting effect of water. CV was measured in the electrolysis reaction of water of the catalyst of Example 2, Comparative Examples 1 and 2 as it can be confirmed by the same electrochemical mechanism through electrolysis. According to Fig. 12, the sponge phenomenon by the water of the catalyst of Example 2 was also the best.

Meanwhile, the catalyst of Example 2 according to the present invention was applied to a two-step reaction, which is a hydrolysis-hydrogenation reaction using wood powder as a reactant and directly converting it into a saccharide alcohol. As shown in Table 2, the ball milled wood meal showed a conversion rate of about 62% and a yield of 31%, while the untreated wood meal showed a conversion rate of 53% and a sugar alcohol content of 23% (sorbitol, Mannitol as well as arabinitol as a minor byproduct). This shows that the catalyst exhibits the most excellent activity among the catalysts reported so far and thus proves the superiority of the metal supported catalyst in which the metal is dispersed in the carbon carrier having the open pore structure according to the present invention.

Claims (16)

A spherical carbon carrier made of a carbon nanomaterial; And
A metal-supported carbon catalyst comprising a metal dispersed in the carbon support,
Wherein the spherical carbon carrier is a dandelion seed having an open pore structure in which the size of the pore increases from the center of the carrier particle to the outer side thereof, or a shape of the sea urchin.
The method according to claim 1,
Wherein the metal is at least one selected from the group consisting of Ru, Pt, Pd, Rh, Al, Mg, Fe, Co, Cu, Ni and Ir.
3. The method of claim 2,
Wherein the metal is present in an amount of 0.1 to 10% by weight based on the total weight of the catalyst.
Supporting a silica spheres (DSS) having an open pore structure in a phenol-formaldehyde resin solution;
Centrifuging the silica spheres supported on the solution;
Removing excess resin from the silica spheres through centrifugation and drying;
Aging the dried silica spheres and carbonizing them; And
The method of producing a carbon carrier according to any one of claims 1 to 3, comprising the step of etching, filtering and drying the carbonized silica spheres.
5. The method of claim 4,
Wherein the aging is carried out at 80 to 110 DEG C for 20 to 25 hours.
5. The method of claim 4,
Wherein the carbonization is carried out in a nitrogen atmosphere at a temperature of 800 to 900 占 폚.
5. The method of claim 4,
Wherein the etching is performed using hydrogen fluoride or sodium hydroxide for 24 to 30 hours.
Mixing a metal precursor solution in a solution containing a spherical carbon nano material having an open pore structure;
Adjusting the pH of the mixed solution to be alkaline;
Reducing the metal ions contained in the metal precursor solution; And
A process for producing a catalyst according to any one of claims 1 to 3, by filtration and washing.
9. The method of claim 8,
Wherein the metal contained in the metal precursor solution is at least one selected from the group consisting of Ru, Pt, Pd, Rh, Al, Mg, Fe, Co, Cu, Ni and Ir.
9. The method of claim 8,
The method of the metal precursor with the platinum precursor, characterized in that the _{PtH 2 Cl 6 · H 2 O} .
9. The method of claim 8,
Wherein said alkaline regulating step comprises adding a sodium hydroxide or ammonium hydroxide solution.
9. The method of claim 8,
Wherein the reducing step is adding sodium borohydride or ethylene glycol.
A process for the production of sorbitol comprising hydrolyzing and hydrogenating cellulose in the presence of a catalyst according to any one of claims 1 to 3.
14. The method of claim 13,
Wherein the step of hydrolyzing and hydrogenating is carried out under hydrogen pressure of 10-100 bar.
14. The method of claim 13,
Wherein the step of hydrolyzing and hydrogenating is carried out at a temperature of 150 to 200 ° C. delete

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