KR101369921B1 - copper-chromite catalyst and preparing method of 1,2-propanediol using thereof - Google Patents

Abstract

The present invention relates to a catalyst for the 1,2-propanediol production reaction through the hydrocracking reaction of glycerol and a method for producing 1,2-propanediol using the same, the active site by introducing a precious metal palladium to the copper-chromium catalyst The present invention relates to a catalyst that can be applied to a continuous process in pellet form while exhibiting high activity even at a low hydrogen partial pressure by increasing the concentration thereof.

Description

Copper-chromium catalyst with a noble metal and a method for preparing 1,2-propanediol using the same {copper-chromite catalyst and preparing method of 1,2-propanediol using approximately}

The present invention relates to a catalyst for the 1,2-propanediol production reaction through the hydrocracking reaction of glycerol and a method for producing 1,2-propanediol using the same, the active site by introducing a precious metal palladium to the copper-chromium catalyst The present invention relates to a catalyst that can be applied to a continuous process in pellet form while exhibiting high activity even at a low hydrogen partial pressure by increasing the concentration thereof.

Recently, biodiesel has received much attention as an alternative energy source for fossil fuels. The biodiesel collectively refers to fuels having the same physical properties as diesel oil, which can be made by processing plant-derived resources such as vegetable oils such as rapeseed seed, soybean oil, waste cooking oil and brown rice oil. Since the biodiesel has the same physical characteristics as general diesel, the biodiesel can be used directly in a diesel engine currently being used, and has a merit of low emission of pollutants.

Such biodiesel is prepared through the synthesis of fatty acid methyl esters by transesterification from plant-derived resources. Glycerol, which is a major by-product of the transesterification reaction, is used in the fields of beauty, pharmaceuticals, foods, etc., but the amount of glycerol supplied is excessively large compared to industrial demand, and eventually, its value has collapsed. For this reason, studies are being actively conducted to convert glycerol, which is a by-product of biodiesel, into other materials of high value.

Among these, 1,2-propanediol produced by the hydrocracking reaction of glycerol is used as a synthetic raw material of pharmaceuticals, cosmetics, polyester, unsaturated polyester, and plasticizer of cellophane. Known as

The conversion from glycerol to 1,2-propanediol is carried out by hydrocracking through a catalyst.

The method using the catalyst has not been studied much yet, US Patent No. 5616817 is preparing a catalyst of a mixture of cobalt, copper, manganese, molybdenum to convert glycerol to 1,2-propanediol , The reaction conditions presented are high pressure conditions of 100 to 700 and high temperature conditions of 180 to 270 ° C., so there is a problem that very harsh conditions are required.

In addition, a copper-chromium catalyst having a spinel structure has been reported as a recently developed catalyst, which has a problem in that the catalyst shows activity under a high hydrogen pressure of 80 bar or more.

Since such high hydrogen pressure is a great burden in the chemical process, it is difficult to commercialize 1,2-propanediol. Therefore, it is urgent to develop a catalyst that exhibits high activity even under low hydrogen pressure.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above process problems and provide a catalyst for 1,2-propanediol production reaction and a method for producing 1,2-propanediol using the same, which exhibit high activity even at low hydrogen pressure. .

The catalyst for the 1,2-propanediol production reaction of glycerol according to an embodiment of the present invention for achieving the above object comprises (A) a metal element and (B) a copper-chromium catalyst, (A) a metal element (B) is characterized in that it is a promoter of a copper-chromium catalyst.

On the other hand, the production method of 1,2-propanediol by the hydrocracking reaction of glycerol according to an embodiment of the present invention for achieving the above object, the hydrocracking reaction is (A) metal element and (B) And a copper-chromium catalyst, wherein the metal element (A) is a catalyst of the copper catalyst (B).

On the other hand, the method for producing a catalyst for 1,2-propanediol production reaction of glycerol according to an embodiment of the present invention for achieving the above object comprises the steps of preparing a metal precursor solution by dissolving at least one metal precursor compound in a solvent; Adjusting the pH of the metal precursor solution to form a precipitate; Aging the precipitate; Filtering and drying the aged precipitate; Calcining the dried precipitate; And adding and kneading the organic binder to the calcined catalyst powder, and then extruding.

When the catalyst according to the present invention is used for the 1,2-propanediol production reaction of glycerol, 1,2-propanediol can be produced in high yield because it shows high activity even at low hydrogen partial pressure and can be applied in a continuous process as pellet form. It can be effective.

1 is an XRD graph of catalysts prepared by Examples 1 to 5 and Comparative Example 1. FIG.
Figure 2 is an XRD graph of the catalyst prepared by Examples 1 to 5 and Comparative Example 1 is completed reduction.
3 is a graph of TPR analysis for the catalyst after the reduction of Examples 1 to 5 and Comparative Example 1 is completed.
4 is a graph of XPS analysis before and after reduction of the catalyst prepared in Comparative Example 1.
5 is a graph of XPS analysis before and after reduction of the catalyst prepared in Example 3.
6 is a graph measuring the conversion, selectivity and yield in the production of 1,2-propanediol of glycerol using the catalyst of Examples 1 to 5 and the catalyst of Comparative Example 1 when the pressure of hydrogen is 40 bar.
FIG. 7 is a graph measuring conversion, selectivity and yield of 1,2-propanediol in the reaction of glycerol using the catalyst of Examples 1 to 5 and the catalyst of Comparative Example 1 when the pressure of hydrogen is 60 bar.
8 is a graph showing the conversion, selectivity, and yield of the glycerol hydrocracking reaction for each catalyst according to the type of precious metal.
9 is a graph showing the result distribution of glycerol hydrocracking reaction for each catalyst through product analysis.
10 is a graph showing the yield of 1,2-propanediol with reaction time in a continuous process experiment using the catalyst of Example 6.
11 is a graph comparing the yields of 1,2-propanediol when the catalysts of Example 6 and Comparative Example 4 are applied to a continuous process.

The details of other embodiments are included in the following description and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and / or features of the present invention and the manner of achieving them will be apparent with reference to the embodiments and drawings described hereinafter. It should be understood, however, that the invention is not limited to the disclosed embodiments, but is capable of many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, The present invention is only defined by the scope of the claims.

Hereinafter, the catalyst for 1,2-propanediol production reaction of glycerol according to the present invention, a method for preparing 1,2-propanediol, and a method for preparing the catalyst will be described in detail.

1,2- of glycerol Propanediol  Catalyst for Production Reaction

The catalyst for the reaction of 1,2-propanediol production of glycerol according to an embodiment of the present invention includes (A) a metal element and (B) a copper-chromium catalyst, wherein (A) the metal element is (B) copper- It is characterized by being a promoter of a chromium catalyst.

It is preferable that the said (A) metal element is palladium here.

The palladium of the present invention is used by dissolving in a solvent in the form of a precursor, the precursor may be, for example, carbide, oxide, chloride, nitride, sulfide, sulfate, nitrate, but the present invention is not limited thereto. The carbides, oxides, chlorides, nitrides, sulfides, sulfates, nitrates and the like may be used alone or in combination of two or more, and they may be in the form of hydrates or anhydrides.

The solvent may be either a polar or nonpolar solvent. As the solvent, the precursor can be dissolved, but is not particularly limited. For example, ethanol, butanol, water, and the like can be used alone or in combination of two or more thereof. In addition, lower alcohols etc. can also be introduce | transduced as a solvent.

The content of the palladium is preferably 0.3 to 10% by weight of the total weight of the catalyst. If the content of palladium is less than the above range, there is a problem of hydrogen adsorption ability by palladium and lack of spillover effect of hydrogen, and if it exceeds the above range, the spinel structure of the copper-chromium catalyst collapses to There is a problem that the chromium atom is present in the form of chromium oxide separately.

Here, the catalyst of the present invention including the above (A), (B) may be in the form of pellets. Although there is no limitation in the form of the catalyst of the present invention, in order to apply to the continuous process, the catalyst in the form of a powder should be molded, preferably in the form of pellets can be used.

Method for producing catalyst

Method for producing a catalyst for 1,2-propanediol production reaction of glycerol according to an embodiment of the present invention comprises the steps of dissolving at least one metal precursor compound in a solvent to prepare a metal precursor solution; Adjusting the pH of the metal precursor solution to form a precipitate; Aging the precipitate; Filtering and drying the aged precipitate; Calcining the dried precipitate; And adding and kneading the organic binder to the calcined catalyst powder, and then extruding. Hereinafter, each step will be described in detail.

The preparation of the catalyst for the 1,2-propanediol production reaction of glycerol of the present invention begins by dissolving the metal precursor compound in a solvent to prepare a metal precursor solution. After preparing the metal precursor compound and the solvent, respectively, the metal precursor compound may be dissolved in the solvent to prepare a metal precursor solution.

The metal precursor compound is not particularly limited, but preferably contains a metal having high activity. In the present invention, the metal precursor compound is selected from a chromium precursor compound and a copper precursor compound as a non-noble metal-based metal precursor. One or more; And a palladium precursor compound as the precious metal-based metal precursor.

The chromium precursor compound, copper precursor compound, and palladium precursor compound used at this time may be, for example, metal salts such as nitrate, acetate, carbonate, acetate, halogen salt and the like; Halides; oxide; It may be a compound such as sulfide, but the present invention is not limited thereto.

The metal salts, halides, oxides, sulfides and the like may be used alone or in combination of two or more, and they may be in the form of hydrates or anhydrides.

The solvent may be a polar or non-polar solvent. The solvent is not particularly limited as long as it can dissolve the metal precursor. For example, ethanol, butanol, distilled water, etc. may be used alone or in combination of two or more. In addition, lower alcohols and the like can also be introduced as a solvent.

Next, the pH of the metal precursor solution is adjusted to form a precipitate. The precipitate is a compound containing a metal element of the metal precursor compound, it may be formed within a specific pH range. The pH adjustment may vary depending on the type of metal precursor compound, but may be performed, for example, by adding an alkali carbonate or sodium hydroxide aqueous solution to the metal precursor solution. The alkali carbonate or sodium hydroxide aqueous solution may be added to the metal precursor solution so that the pH may be 7 to 13, and the specific pH value is within the range according to the type and content of the metal component contained in the metal precursor solution. May vary.

The particle size, the formation rate, etc. of the precipitate may vary depending on the concentration and the addition rate of the alkali carbonate or the aqueous sodium hydroxide solution. For example, if the addition rate of the alkali carbonate or sodium hydroxide aqueous solution is too fast or the concentration is too high, there is a problem in that the activity of the catalyst is lowered due to the increase in the size of the precipitate formed particles. On the other hand, if the addition rate of the alkali carbonate or sodium hydroxide aqueous solution is too slow or the concentration is too low, the efficiency of the catalyst production may be reduced. Therefore, in order to effectively suppress the problems, the concentration of the alkali carbonate or sodium hydroxide aqueous solution is set within a range of 0.5 to 3 mol / L, and the alkali carbonate or sodium hydroxide aqueous solution is added at a rate of 0.1 to 10 mL per minute. It can be added to the metal precursor solution.

Next, when the pH of the metal precursor solution reaches a specific value within the range of 9 to 13, the precipitate may be aged. The aging may be carried out for 2 to 12 hours at 50 ~ 90 ℃ so that the precipitation reaction occurs sufficiently. If the aging temperature is too low or too high, it is difficult to form a precipitate having a high particle size of catalytic activity, and as described above, the aging temperature can be set at 50 to 90 ° C, preferably 60 to 80 ° C.

Next, it is sufficiently washed with distilled water until the alkali carbonate aqueous solution or the sodium hydroxide aqueous solution remaining in the precipitate is completely removed. The washed precipitate is then filtered and dried. The drying is sufficiently carried out at 80 ~ 200 ℃ until the precipitate is completely dried.

Next, the dried precipitate may be calcined to remove organic matter remaining in the precipitate and to form an appropriate alloy phase. The calcination may be carried out in a temperature range of 400 ~ 700 ℃ under air atmosphere or oxygen atmosphere. The specific calcination temperature can be determined at a temperature at which an alloy phase exhibiting high catalytic activity can be formed and can be varied depending on the kind and content of the metal component contained in the formed precipitate. For example, metal components such as copper, chromium, and nickel may form an appropriate alloy phase when calcined at 400 to 700 ° C, preferably 500 to 600 ° C.

Next, if necessary, in order to increase the activity of the catalyst, the calcined catalyst powder may be reduced. The reduction may be performed at 50 to 400 ° C. after supplying hydrogen gas at a predetermined rate to form a hydrogen atmosphere. In addition, the reduction may be performed in a mixed gas atmosphere in which hydrogen gas and helium, argon, nitrogen gas and the like are mixed.

Next, the organic binder is added to the catalyst powder on which the calcination is completed, and kneaded, followed by extrusion molding. It is preferable that the said organic binder contains 1 or more types chosen from the organic binder for ceramics containing an ether bond. Specific examples thereof include PMB-15U, PMB-40H, and MC-40H, but are not limited thereto.

The catalyst powder to which the organic binder is added is uniformly mixed using a mixer, and then distilled water is mixed to prepare a dough form for molding. Thereafter, the pellets are prepared by cutting at regular intervals while extruding at an appropriate pressure through an extruder.

Next, the finished pelletized catalyst is dried. At this time, moisture is removed.

On the other hand, since the organic binder added for extrusion molding interferes with the catalytic activity, in order to remove it and increase the strength of the catalyst, the dried catalyst is further calcined at a high temperature. At this time, the firing temperature is preferably about 550 占 폚, and the time is preferably 6 to 8 hours.

1,2- Of propanediol  Manufacturing method

In the method for preparing 1,2-propanediol by hydrocracking of glycerol according to an embodiment of the present invention, the hydrocracking reaction includes (A) a metal element and (B) a copper-chromium catalyst, The metal element (A) is characterized by a catalyst characterized in that the (B) is a promoter of the copper-chromium catalyst.

That is, it is characterized by the use of the catalyst of the present invention described above, the description of the catalyst will be omitted here.

Specifically, the method for preparing 1,2-propanediol by the hydrocracking reaction of glycerol of the present invention comprises the steps of introducing glycerol and the catalyst of the present invention into the reactor, while stirring the glycerol and the catalyst, hydrogen gas in the reactor Supplying and reacting the glycerol and the hydrogen. At this time, the catalyst of the present invention has a pellet form, the production method can be carried out continuously.

The process for producing propanediol according to one aspect of the present invention begins with preparing glycerol and the catalyst, respectively, and then introducing the glycerol and the catalyst into the reactor. The glycerol may be a byproduct generated in the production of biodiesel, but the present invention is not limited thereto. For example, the glycerol may be synthesized through various routes or produced as a by-product of various synthesis reactions. In addition to these, commercially available ones may be used as the glycerol.

When the amount of the catalyst of the present invention is insufficient, the activity may not appear sufficiently in the reaction process, and as the amount of the catalyst increases, a high yield of propanediol may be obtained, but considering the economical content, the catalyst content is 100 parts by weight of glycerol It may be 1 to 10 parts by weight, more preferably 2 to 5 parts by weight. As the reactor, for example, a batch reactor can be used.

Next, after the reactor is completely sealed, hydrogen gas is supplied into the reactor, for example, for 30 to 60 minutes while stirring the glycerol and the catalyst so that the inside of the reactor is formed in a hydrogen gas atmosphere. In addition, the mixed gas which mixed hydrogen gas, helium, argon, nitrogen gas, etc. may be supplied in the said reactor.

Next, the inside of the reactor is elevated and heated to a predetermined pressure and temperature range to react the glycerol and the hydrogen. In the reaction, when the reaction temperature is too low, the production efficiency of 1,2-propanediol is lowered, so the reaction temperature is 150 to 300 ° C, preferably 210 to 280 ° C, more preferably 220 to 260 ° C. to be. If the reaction temperature is lower than 150 ° C lower conversion of glycerol, higher than 300 ° C is not good selectivity in terms of energy efficiency is not preferable.

At the time of the said reaction, it is suitable for the reaction pressure to maintain 20-100 atmospheres, preferably 60-90 atmospheres. The reaction can be carried out, for example, for 0.5 to 48 hours, preferably for 5 to 15 hours, so that a sufficient conversion from glycerol to propanediol can occur.

According to the above, 1,2-propanediol can be prepared directly from glycerol in high yield using a catalyst having an appropriate amount of a suitable metal. The production of 1,2-propanediol can be carried out at relatively low pressure and low temperature conditions, thereby improving the economics, safety, efficiency and the like of the 1,2-propanediol manufacturing process.

Hereinafter, the catalyst of the present invention and a method for preparing 1,2-propanediol will be described in more detail with reference to Examples, but the following Examples are provided to illustrate the present invention in more detail. It is not limited to the following example.

Example

Example  One

(1) Preparation of Catalyst

The amount of palladium precursor was calculated and added so that the weight of palladium was 0.3% by weight of the total catalyst, but the amount of copper and chromium precursor was adjusted so that the molar ratio of the number of atoms of copper and chromium in the catalyst was 1: 2. Palladium chloride was used as the palladium precursor, copper nitrate was used as the copper precursor, and chromium nitrate was used as the chromium precursor, and these were quantified and dissolved in 350 mL of distilled water to prepare a first solution.

24 g of sodium hydroxide was dissolved in 200 mL of distilled water to prepare a second solution, and the precipitate was formed by adding the second solution to the first solution while stirring until the pH was 10 while measuring pH.

Next, the precipitate was aged while maintaining the temperature of the solution in which the precipitate was formed at 70 ° C. and stirring for 4 hours. The precipitate was filtered to filter the precipitate, washed with 1000 mL of distilled water, dried at 80 ° C. for 24 hours, and then the dried precipitate was ground to uniform particles. Next, the catalyst of the present invention was prepared by calcination for 6 hours at a temperature of 550 ° C. and an air atmosphere.

(2) Preparation of 1,2-propanediol

The reaction to produce 1,2-propanediol from glycerol was carried out through a high pressure batch reaction system. 50 g of glycerol and 1 g of catalyst were put together in a reactor, and after being sealed, high pressure was formed with hydrogen and then proceeded at 220 ° C. for 12 hours. The pressure of hydrogen was divided into 40 bar and 60 bar.

Example  2

A catalyst was prepared in the same manner as in Example 1 except that palladium chloride was added so that the amount of palladium was 0.5% by weight of the total catalyst, and the catalyst was subjected to 1,2-propanediol production of glycerol. 1,2-propanediol was prepared.

Example  3

A catalyst was prepared in the same manner as in Example 1 except that palladium chloride was added so that the amount of palladium was 1% by weight of the total catalyst, and the catalyst was subjected to 1,2-propanediol production of glycerol. 1,2-propanediol was prepared.

Example  4

A catalyst was prepared in the same manner as in Example 1 except that palladium chloride was added so that the amount of palladium was 3% by weight of the total catalyst weight, and the catalyst was subjected to 1,2-propanediol production of glycerol. 1,2-propanediol was prepared.

Example  5

A catalyst was prepared in the same manner as in Example 1 except that palladium chloride was added so that the amount of palladium was 10% by weight of the total catalyst weight, and the catalyst was used for 1,2-propanediol reaction of glycerol. 1,2-propanediol was prepared.

Example  6

(1) Preparation of Catalyst

To 200 g of the palladium / copper-chromium catalyst powder prepared in Example 1, 10 g of organic binder MC-40H (5 wt% based on the weight of the catalyst) was added and mixed uniformly using a mixer.

50 mL of distilled water was mixed to form a dough for molding, and the pellet catalyst was prepared by cutting at an interval of 3 mm while extruding through an extruder, and dried at room temperature for 24 hours to remove moisture without internal and external cracking.

Thereafter, the pellet-type catalyst was completed by baking the dried catalyst at 550 ° C. for 6 hours to remove the organic binder and improve the strength.

(2) Preparation of 1,2-propanediol

The reaction to produce 1,2-propanediol from glycerol was applied to a bench scale continuous process. To this end, after loading the prepared catalyst in the reactor, the internal temperature was maintained between 200 ~ 240 ℃ through the temperature control of the heating jacket surrounding the reactor for temperature control of the reactor.

Example  7 ( Pellet type  catalyst)

A pellet catalyst was completed in the same manner as in Example 6, except that 20 g of the organic binder MC-40H was used (10 wt% based on the weight of the catalyst).

Comparative Example  One

(1) Preparation of Catalyst

The first solution was prepared by adjusting the addition amount of the copper and chromium precursors so that the molar ratio of the atomic number of copper and chromium in the catalyst was 1: 2, and then dissolving it in 350 mL of distilled water. In this case, the copper precursor was copper nitrate, and the chromium precursor was chromium nitrate.

24 g of sodium hydroxide was dissolved in 200 mL of distilled water to prepare a second solution, and the precipitate was formed by adding the second solution to the first solution while stirring until the pH was 10 while measuring pH.

Next, the precipitate was aged while maintaining the temperature of the solution in which the precipitate was formed at 70 ° C. and stirring for 4 hours. The precipitate was filtered to filter the precipitate, washed with 1000 mL of distilled water, dried at 80 ° C. for 24 hours, and then the dried precipitate was ground to uniform particles. Next, the resultant was calcined for 6 hours at a temperature of 550 ° C. and an air atmosphere to prepare a copper-chromium catalyst.

(2) Preparation of 1,2-propanediol

1,2-propanediol was prepared in the same manner as in Example 1, except that the catalyst prepared in (1) of Comparative Example 1 was used.

Comparative Example  2

A catalyst prepared in the same manner as in Example 1 was used, except that ruthenium chloride was added instead of palladium to calculate the amount of ruthenium chloride so that the weight of ruthenium was 0.3% by weight. It was molded by the method to prepare a pellet catalyst.

Comparative Example  3

A catalyst prepared in the same manner as in Example 1 was used except that platinum chloride was added instead of palladium to calculate the amount of platinum chloride so that the weight of platinum was 0.3% by weight of the total catalyst. It was molded by the method to prepare a pellet catalyst.

Comparative Example  4

(1) Preparation of Catalyst

Except that no palladium chloride was used at all, a catalyst prepared in the same manner as in Example 1 was molded in the same manner as in Example 6 to prepare a pellet catalyst.

(2) Preparation of 1,2-propanediol

1,2-propanediol was prepared in the same manner as in Example 6, except that the catalyst prepared in (1) of Comparative Example 5 was used.

Comparative Example  5

200 g of the palladium / copper-chromium catalyst powder prepared in Example 1 was loaded into a hopper of a pelletizer, and pelletization was performed by appropriately increasing the pressure and rotational speed of the rotating plate. This produced a pellet catalyst without the addition of the organic binder and other additives.

Comparative Example  6

A catalyst was prepared in the same manner as in Example 6, except that 2 g of organic binder MC-40H (1 wt% based on the weight of the catalyst) was used.

Comparative Example  7 ( Pelletized  Way)

A catalyst was prepared in the same manner as in Example 6, except that 40 g of organic binder MC-40H (20 wt% based on the weight of the catalyst) was used.

evaluation

One. For the crystal structure of the catalyst and the structure after reduction XRD  analysis

XRD analysis was performed to observe the crystal structure and the structure after reduction of the catalysts prepared in Examples 1 to 5 and Comparative Example 1.

1 is an XRD graph of the catalysts prepared by Examples 1 to 5 and Comparative Example 1, and FIG. 2 is an XRD graph of the catalysts prepared by Examples 1 to 5 and Comparative Example 1 where the reduction is completed.

As can be seen first in Figure 1, XRD analysis of the catalyst prepared by Examples 1 to 5 and Comparative Example 1, the copper-chromium catalyst prepared by Comparative Example 1 shows that the tetragonal spinel (tetragonal spinel) structure Could know. In addition, it was confirmed that the catalysts of Examples 1 to 5 containing palladium also have a tetragonal spinel structure.

Particularly, in Examples 4 and 5, XRD characteristic peaks corresponding to chromium oxide (Cr ₂ O ₃ ) could be confirmed, which means that copper and palladium had an alloy form at a temperature lower than the copper-chromium structure formation temperature, thereby resulting in copper- It was judged that the chromium that did not form chromium had an oxide form.

On the other hand, the reduction process was carried out for 2 hours in a hydrogen atmosphere of 300 ℃, as can be seen in Figure 2, it was confirmed that the reduced catalyst of Comparative Example 1 has a cubic spinel (cubic spinel) structure. In addition, it was confirmed that the catalysts of Examples 1 to 5 including palladium also have a cubic spinel structure, and the chromium oxide was not reduced.

2. Catalyst TPR  analysis

TPR analysis was performed to determine the reduction characteristics of the catalyst. After the reduction is completed, the catalyst is structurally the same, but to confirm the effect of palladium in the reduction process.

3 is a graph of TPR analysis for the catalyst after the reduction of Examples 1 to 5 and Comparative Example 1 is completed.

As can be seen in Figure 3, the catalyst of Comparative Example 1 was able to identify one large reduction peak in the vicinity of 150 ℃. As the palladium is supported, it was confirmed that a new reduction peak is formed at around 100 ° C., and as can be seen in Examples 1 to 4, it can be seen that the size of the peak is increased. It can be seen that the reduction of the catalyst itself is improved by introducing palladium into the catalyst.

3. Catalyst XPS  analysis

Spinel-structured copper-chromium catalysts are exposed to the surface of Cu in the lattice as a result of the reduction process to form nano-sized Cu particles, which are known to act as active sites in the present reaction. Therefore, in order to confirm the ratio of Cu ⁰ of the surface directly participating in the reaction, XPS analysis was performed.

4 is a graph of XPS analysis before and after reduction of the catalyst prepared in Comparative Example 1.

5 is a graph of XPS analysis before and after reduction of the catalyst prepared in Example 3.

As a result of the XPS analysis, it was confirmed that Cu ⁰ , which is an active point of the catalyst after reduction, was very high in the catalyst prepared in Example 3.

That is, the oxidation state of copper through the XPS analysis of Comparative Example 1 and Example 3 is as shown in Table 1, the catalyst of the present invention is carried by palladium, so that the amount of Cu ⁰ , the active point of the catalyst after reduction is increased I could confirm it.

Example 3 Comparative Example 1 Before reduction After reduction Before reduction After reduction Cu ^{2 +} 0.77 0.46 0.73 0.65 Cu ⁰ 0.23 0.54 0.27 0.35

4. 1,2- of glycerol Propanediol  Measure conversion, selectivity, and yield

The catalysts of Examples 1 to 5 and the catalyst of Comparative Example 1 were used for the conversion reaction of 1,2-propanediol of glycerol. The method for preparing 1,2-propanediol is as described in Example 1 above.

6 is a graph measuring the conversion, selectivity and yield in the production of 1,2-propanediol of glycerol using the catalyst of Examples 1 to 5 and the catalyst of Comparative Example 1 when the pressure of hydrogen is 40 bar.

FIG. 7 is a graph measuring conversion, selectivity and yield of 1,2-propanediol in the reaction of glycerol using the catalyst of Examples 1 to 5 and the catalyst of Comparative Example 1 when the pressure of hydrogen is 60 bar.

As can be seen in Figures 6 and 7, it was confirmed that the activity of the catalyst of the present invention (Examples 1 to 5) was improved under both reaction conditions while supporting palladium.

The reaction activity shows a volcano curve, and in particular, the catalysts of Examples 2 and 3 show the highest catalytic activity. This may be because the reduction of the catalyst is improved in view of the TPR and XPS analysis results, and the number of Cu ⁰ , which is an active point of the present reaction, increases on the surface of the catalyst.

5. Moldability Test of Catalyst

In order to apply to the continuous process, the catalyst of the present invention should be molded, and the experimental results of molding the catalyst according to the methods described in Examples 6 and 7 and Comparative Examples 5 to 7 are summarized in Table 2 below.

division Catalytic Molding Method Organic binder Organic Binder Mixing Ratio Catalytic Molding Results Example 6 Extrusion molding MC-40H 5wt% of the total weight of the catalyst Pelletized Catalyst Forming Example 7 Extrusion molding MC-40H 10wt% of the total weight of the catalyst Pelletized Catalyst Forming Comparative Example 5 Pellet molding - - Not molded Comparative Example 6 Extrusion molding MC-40H 1wt% of the total weight of the catalyst Not molded Comparative Example 7 Extrusion molding MC-40H 20wt% of the total weight of the catalyst Not molded

First, in Comparative Example 5, the catalyst powder did not flow into the pelletizing plate from the raw material hopper because of poor flowability of the catalyst powder. In addition, agglomeration of the catalyst powder itself is very strong, and when exposed to air, the phenomenon of absorbing and agglomeration of moisture in the air was found. This phenomenon is the worst condition in using the pellet forming method, even if the additives such as silica, alumina, etc. in order to improve the flowability and prevent the aggregation phenomenon was not improved. Therefore, in the case of the palladium / copper-chromium catalyst of the present invention, it was confirmed that molding was impossible through the pellet molding method as in Comparative Example 5.

Through Examples 6, 7 and Comparative Examples 6, 7 using the extrusion method, it was confirmed that the possibility of molding varies depending on the degree of use of the organic binder.

In the case of Comparative Example 6, the amount of the organic binder was small so that the dough for the catalyst molding was not formed. In the case of Comparative Example 7, the amount of the organic binder was so large that the viscosity of the catalyst dough was so high that the adhesion to the wall of the extruder increased, so that proper catalyst molding could not be performed.

As a result, as in Examples 6 and 7, when the amount of the organic binder used was 5 to 10% by weight based on the total weight of the catalyst, the best type of catalyst dough could be obtained, and a pellet-type catalyst could be obtained.

In the case of the organic binder, it must be removed after the catalyst molding, and if not removed, it may cause deactivation and deactivation of the catalyst.

As a result of numerous experiments, it was confirmed that all organic binders were removed after 24 hours of drying and 6 hours of baking at a temperature of 550 ° C. At temperatures lower than 550 ° C., the organic binder was not completely removed. At temperatures higher than 550 ° C., the spinel structure collapsed due to sintering of the metal in the palladium / copper-chromium catalyst.

6. Comparison of activity according to the type of added precious metal

The effect on the type of added precious metals was tested for the activity analysis of the prepared / molded catalysts.

8 is a graph showing the conversion, selectivity, and yield of the glycerol hydrocracking reaction for each catalyst according to the type of precious metal.

9 is a graph showing the result distribution of the glycerol hydrocracking reaction for each catalyst through the product analysis.

After selecting three kinds of palladium, ruthenium, and platinum noble metal candidates among noble metal candidates capable of increasing hydrogen affinity, a copper-chromium catalyst in which 1% by weight of the noble metal was added was prepared.

The results of each batch test are shown in FIGS. 8 and 9 (reaction conditions: 220 ° C., 60 bar, H ₂ ).

As can be seen in Figure 8, the catalyst according to Example 6 of the present invention carrying palladium showed the best yield of 1,2-propanediol.

In order to confirm the difference according to the type of added precious metals, the product is analyzed and shown in FIG. 9. In the case of palladium, the activity increased toward 1,2-propanediol by increasing the activity toward the hydrocracking reaction intended in the present invention, whereas in the case of platinum, the reaction activity was increased toward CC bond cleavage rather than CO bond cleavage. It was confirmed that the amount of ethylene glycol increased. In addition, in the case of ruthenium, the hydrocracking reaction occurred excessively, so that the decomposition reaction proceeded to 1-propanol, and thus the amount of 1,2-propanediol was reduced.

Through the above experiments, it was confirmed that palladium is most suitable as a noble metal which can increase the reaction activity at low hydrogen pressure to produce 1,2-propanediol from glycerol among precious metals.

7. Continuous process application experiment

In order to investigate the activity of the pelletized palladium / copper-chromium catalyst completed by Example 6, it was applied to a bench scale continuous process.

After loading the catalyst of Example 6 into the reactor to determine the reaction conditions in the continuous process, the continuous reaction was carried out under the conditions described in Example 6. In order to control the temperature of the reactor, the internal temperature was controlled by controlling the temperature of the heating jacket surrounding the reactor.

Since the continuous process is an exothermic reaction, unlike the batch reactor, since the reactants continuously enter the structure, the reaction temperature showing the optimum reaction yield is different due to the heat of reaction by the reaction.

As a result of numerous experiments, it was confirmed that the temperature inside the continuous reactor should be maintained at a level of 200 to 240 ° C, more preferably 205 to 220 ° C.

In addition, when the reactant in the cold state meets the catalyst zone of the reactor, the phenomenon that the reactant cannot be active until the reactor passes by the heating until it passes through the reactor due to sudden heating occurs or the catalyst is destroyed by heat shock. And some heat must be transferred to the reactants in the pre-heater zone in front of the reactor to solve the coking problem.

Through a number of experiments, the relationship between temperature and yield at the front end of the reactor was confirmed.

10 is a graph showing the yield of 1,2-propanediol with reaction time in a continuous process experiment using the catalyst of Example 6. The temperature of the reactor shear preheater zone of the initial 0-100 hours was 100 degreeC, and the temperature of the preheater zone after 100 hours was 200 degreeC. The reaction hydrogen pressure was fixed at 60 bar.

As can be seen in Figure 10, when the temperature of the pre-heater zone of the front end of the reactor is 100 ℃, it was confirmed that the reaction is not sufficiently reacted while passing the reactor continuously because the reactant is not sufficiently heated. In this case, the yield was reduced by about 10% from the maximum yield.

However, it was confirmed that the maximum yield was reached when the temperature of the preheater zone at the front end of the reactor was 200 ° C.

That is, in the continuous process through Fig. 10, the temperature control inside the reactor is also important, but before reaching the reactor, the temperature of the preheater zone of the front end to supply heat to the reactant is more important, the optimum temperature is 150 It could be confirmed that the ~ 250 ℃, more preferably 180 ~ 220 ℃.

In addition, the superiority in the continuous process application of the catalyst of Comparative Example 4 and the catalyst of Example 6 was compared.

11 is a graph comparing the yields of 1,2-propanediol when the catalysts of Example 6 and Comparative Example 4 are applied to a continuous process.

In Comparative Example 4, the catalyst was reacted at 80 bar, but initially showed a yield of 80%. However, as time passed, the reaction activity decreased, resulting in a decrease in yield due to deactivation.

On the other hand, the catalyst of Example 6 was found to show a yield of about 80% or more, which was almost the same as that of Comparative Example 4, although the continuous process was performed at 60 bar. In addition, even if the reaction continued for a long time it was confirmed that the yield is maintained without significant change.

This confirmed that the activity of the catalyst was increased by the palladium added as a promoter. In addition, palladium trapped C atoms in the metal lattice could be interpreted to cause less coking than the catalyst of Comparative Example 4.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. Therefore, the scope of the present invention should not be construed as being limited to the embodiments described, but should be determined by the scope of the appended claims, as well as the appended claims.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It is possible. Accordingly, the spirit of the present invention should be understood only in accordance with the following claims, and all equivalents or equivalent variations thereof are included in the scope of the present invention.

Claims (16)

(A) palladium; And
(B) a copper-chromium catalyst;
Palladium (A) is a catalyst for 1,2-propanediol production reaction of glycerol, characterized in that (B) is a promoter of copper-chromium catalyst.
delete The method of claim 1,
The catalyst comprising the (A) palladium, (B) copper-chromium catalyst is in the form of a pellet, the catalyst for 1,2-propanediol production reaction of glycerol.
The method of claim 1,
The catalyst for the 1,2-propanediol production reaction of glycerol, characterized in that the content of (A) palladium is 0.3 to 10% by weight.
In the method for producing 1,2-propanediol by hydrocracking reaction of glycerol,
The hydrocracking reaction is,
(A) palladium; And
(B) a copper-chromium catalyst;
(A) The palladium is a production method, characterized in that by the catalyst characterized in that (B) a copper-chromium catalyst as a promoter.
delete 6. The method of claim 5,
The catalyst comprising the (A) palladium, (B) copper-chromium catalyst is characterized in that the 1,2-propanediol to be produced continuously.
6. The method of claim 5,
The content of palladium (A) is 0.3 to 10% by weight of the production method.
8. The method of claim 7,
The continuous reactor internal temperature during the manufacturing method is characterized in that 200 ~ 240 ℃.
8. The method of claim 7,
The temperature of the preheater zone at the front end of the continuous reactor during continuous production is characterized in that the 150 ~ 250 ℃.
Preparing a metal precursor solution by dissolving a chromium precursor compound as a non-noble metal-based metal precursor, at least one selected from a copper precursor compound, and a palladium precursor compound as a noble metal-based precursor in a solvent;
Adjusting the pH of the metal precursor solution to 7-13 to form a precipitate;
Aging the precipitate;
Filtering and drying the aged precipitate;
Calcining the dried precipitate; And
Adding an organic binder to the calcined catalyst powder, kneading and extruding;
Method for producing a catalyst for producing 1,2-propanediol comprising a.
delete delete 12. The method of claim 11,
The calcination is a method for producing a catalyst for producing 1,2-propanediol, characterized in that carried out in an air or oxygen atmosphere in the temperature range of 400 ~ 700 ℃.
12. The method of claim 11,
The organic binder is a method for producing a catalyst for producing 1,2-propanediol, characterized in that it comprises one or more of the binder for the ceramic containing an ether bond.
12. The method of claim 11,
Method of producing a catalyst for producing 1,2-propanediol, characterized in that it further comprises the step of firing after the extrusion.

Images