KR102210508B1 - Preparing method of catalyst for dehydration of glycerin, and preparing method of acrolein - Google Patents

Abstract

The present invention relates to a method of preparing a catalyst for a glycerin dehydration reaction, a catalyst for a glycerin dehydration reaction and a method for preparing acrolein prepared accordingly, and according to the manufacturing method, the selectivity of acrolein can be improved by minimizing the generation of by-products. In addition, since it has sufficient mechanical strength, it is possible to prepare a catalyst for glycerin dehydration reaction that can be applied in an actual process.

Description

A method for producing a catalyst for glycerin dehydration and a method for producing acrolein TECHNICAL FIELD [PREPARING METHOD OF CATALYST FOR DEHYDRATION OF GLYCERIN, AND PREPARING METHOD OF ACROLEIN]

The present invention relates to a method for preparing a catalyst for a glycerin dehydration reaction, a catalyst for a glycerin dehydration reaction prepared accordingly, and a method for preparing acrolein, and more specifically, it is possible to improve the selectivity of acrolein by minimizing the generation of by-products. Rather, it relates to a method for producing a catalyst for glycerin dehydration reaction that can be applied in an actual process because it has sufficient mechanical strength.

*Acrolein is a simple unsaturated aldehyde compound, has high reactivity including incomplete reactive groups, and is used as a major intermediate for the synthesis of various compounds. In particular, acrolein has been widely used as an intermediate product for the synthesis of acrylic acid, acrylic acid ester, superabsorbent resin, animal feed supplement, or food supplement.

In the past, such acrolein was prepared mainly through atmospheric oxygen and selective gas phase oxidation reactions using propylene synthesized in an petroleum process as a starting material. However, as environmental problems such as the reduction of fossil fuels and the greenhouse effect gradually emerged, many studies on the method of synthesizing acrolein using renewable raw materials that are not based on fossil fuels have been conducted.

Accordingly, as a natural product, glycerin, which can be obtained as a by-product of the process of synthesizing biodiesel, has attracted much attention as a raw material for manufacturing acrolein. In particular, the market size of glycerin is increasing according to the production amount of biodiesel, and a method that can be applied industrially is being studied due to the decrease in the price of glycerin.

As an example, a method of dehydrating glycerin in the presence of a catalyst to obtain it in the form of a mixture of acrolein and acrylic acid is known. The dehydration reaction of glycerin proceeds as a gas phase oxidation reaction in the presence of a catalyst, and the use of a catalyst is essential.

However, the previous catalysts used to prepare acrolein were in the process of synthesizing high purity acrolein by producing by-products such as hydroxypropanone, propanaldehyde, acetaldehyde, acetone, a polycondensation product of glycerin, and cyclic glycerin ether. There was a limitation in use, and there was a limitation in causing deactivation of the catalyst by forming coke on the catalyst by producing phenol or polyaromatic compound as a by-product.

In addition, catalysts used previously have low mechanical strength, so there is a limitation in applying them to actual processes such as generating internal pressure during reaction experiments.

Accordingly, it is possible to increase the selectivity of acrolein by minimizing the generation of by-products that cause the above problems, and to improve the conversion rate and reaction yield of glycerin, while having sufficient mechanical strength, the development of a catalyst system that can be applied in the actual process is difficult. Is required.

The present invention is to provide a catalyst for a glycerin dehydration reaction that can be applied in an actual process because it is possible to improve selectivity of acrolein by minimizing the generation of by-products, and has sufficient mechanical strength.

In addition, the present invention is to provide a catalyst for a glycerin dehydration reaction prepared according to the above production method.

In addition, the present invention relates to a method for producing acrolein using the glycerin dehydration catalyst.

The present invention is a composite metal oxide containing zirconium (Zr), tungsten (W) and phosphorus (P).

5 to 20% by weight of at least one inorganic metal sol selected from the group consisting of silica sol, alumina sol, titania sol and zirconia sol; And at least one alcohol selected from the group consisting of glycerin, isopropyl alcohol, diacetone alcohol, methanol, ethanol, and propanol in the balance; mixing with a coagulant; And

Extruding the mixture; containing, it provides a method for producing a catalyst for glycerin dehydration reaction.

And, the present invention provides a glycerin dehydration catalyst prepared according to the method for preparing the glycerin dehydration catalyst.

In addition, the present invention provides a method for producing acrolein comprising reacting glycerin in the presence of the catalyst for glycerin dehydration.

Hereinafter, a method for preparing a catalyst for dehydration of glycerin, a catalyst for dehydration of glycerin, and a method for producing acrolein according to a specific embodiment of the present invention will be described in more detail.

In the present specification, "glycerin dehydration reaction" refers to a whole process in which water is separated in glycerin molecules or between glycerin molecules.

According to one embodiment of the invention, a composite metal oxide containing zirconium (Zr), tungsten (W) and phosphorus (P) is at least one inorganic metal sol selected from the group consisting of silica sol, alumina sol, titania sol, and zirconia sol. 5 to 20% by weight; And at least one alcohol selected from the group consisting of glycerin, isopropyl alcohol, diacetone alcohol, methanol, ethanol, and propanol in the balance; mixing with a coagulant; And extruding the mixture; containing, a method for producing a catalyst for glycerin dehydration reaction may be provided.

The inventors of the present invention have limited use in the process of synthesizing high-purity acrolein by generating a large amount of by-products of the previous catalysts used to produce acrolein, and the mechanical strength is low, so that the actual process is difficult to generate internal pressure during the reaction experiment. Recognizing that it is difficult to apply, research was conducted on a method of manufacturing a catalyst having sufficient mechanical strength, as well as improving the selectivity of acrolein by minimizing the generation of by-products. As a result, a catalyst for glycerin dehydration reaction prepared by mixing a composite metal oxide containing zirconium (Zr), tungsten (W) and phosphorus (P) with a coagulant of a specific composition and extruding it has sufficient mechanical strength, such as high compressive strength. When used in the glycerin dehydration reaction, it was confirmed through an experiment that acrolein was prepared in high yield and high conversion rate, and the invention was completed.

In particular, the catalyst for glycerin dehydration can significantly reduce the generation of by-products compared to the catalyst for dehydration of glycerin such as zeolite, sulfate, or phosphate or for producing acrolein, thus increasing the yield of acrolein.

In addition, in the case of the existing catalyst, the mechanical strength is low, and when applied to the actual process, various problems have occurred, such as generating an internal pressure. However, according to the method for preparing the catalyst for glycerin dehydration reaction, a composite metal oxide is mixed with an inorganic metal sol and an alcohol. A catalyst having sufficient mechanical strength can be prepared by mixing and extruding with a coagulant containing.

The composite metal oxide used in the method for preparing the catalyst for the glycerin dehydration reaction includes zirconium (Zr), tungsten (W), and phosphorus (P). In the composite metal oxide, since each component can serve as an acid point for giving a proton or receiving an unshared electron pair by strongly bonding to each other, acrolein can be prepared by dehydrating glycerin with higher selectivity, conversion and yield.

In particular, the composite metal oxide essentially contains zirconium (Zr), and zirconium forms zirconium phosphate together with phosphorus so that the phosphorus component is not lost in the reaction process, and thus is used in the conventional oxide catalyst that does not contain zirconium. In contrast, since phosphorus is stably present, the catalytic activity is higher than that of the existing catalyst, and stable catalytic activity for a long time can be shown.

In addition, in the composite metal oxide, phosphorus is bonded to oxygen in the form of an oxide of phosphoric acid (PO ₄ ), thereby increasing acid points such as Bronsted acid point or Lewis acid point, thereby more efficiently dehydrating glycerin. I can make it.

In addition, the composite metal oxide may further include at least one transition metal selected from the group consisting of Zn, V, Fe, Mo, Ce, and Cu in addition to zirconium (Zr), tungsten (W), and phosphorus (P). .

The transition metal may be in a state in which zirconium (Zr), tungsten (W), phosphorus (P) and oxygen are shared in the composite metal oxide. The composite metal oxide may further include the transition metal to improve selectivity of acrolein and suppress the generation of hydroxyacetone, a by-product.

Meanwhile, the composite metal oxide may be represented by Formula 1 below.

[Formula 1]

Zr(M ₁ ) _p (M ₂ ) _q W _r P _s H _x O _y

In Formula 1,

M ₁ and M ₂ are each independently a transition metal selected from the group consisting of Zn, V, Fe, Mo, Ce and Cu,

p is a real number greater than 0 and not more than 1,

q is a real number from 0 to 1,

r is a real number greater than 0 and not more than 1,

s is a real number greater than 0 and not more than 10,

Each of x and y is independently a real number of 0.1 or more and 20 or less.

The content of hydrogen and oxygen in the composite metal oxide, that is, the x and y values of Formula 1 may be appropriately adjusted according to the content and component ratio of zirconium, tungsten, phosphorus, and transition metals that may be additionally included, but preferably It can be a real number of 0.1 to 20.

Further, in Formula 1, one of M ₁ and M ₂ may be Zn, and the other may be V. In this way, in the complex metal oxide containing zinc and vanadium in addition to zirconium, tungsten, and phosphorus, zinc and vanadium are metal oxides, which remove coke or provide a Bronsted acid point, thereby enhancing the activity of the catalyst, and is stable for a long time Catalytic activity can be maintained.

In addition, the composite metal oxide may include mixing a zirconium precursor, a tungsten precursor, and a phosphorus precursor; And drying and firing the mixed solution.

The zirconium precursor, tungsten precursor, and phosphorus precursor are a generic term for a material for providing zirconium, tungsten, and phosphorus contained in the prepared glycerin dehydration catalyst, respectively, and, for example, any of the zirconium, tungsten, and phosphorus It may be in the form of an oxide or salt containing one. More specifically, the tungsten precursor may be ammonium metatungstate hydrate, the phosphorus precursor may be ammonium phosphate, and the zirconium precursor may be zirconium oxychloride.

And, in the step of mixing the zirconium precursor, tungsten precursor and phosphorus precursor, as well as the zirconium precursor, tungsten precursor and phosphorus precursor, of one or more transition metals selected from the group consisting of Zn, V Fe, Mo, Ce, and Cu. The precursor may be further included and mixed. In addition, as the precursor of the transition metal, nitrate of each transition metal may be used.

Next, the mixture prepared by mixing the zirconium precursor, tungsten precursor and phosphorus precursor is dried and fired.

More specifically, in the drying step, the mixed solution may be dried for 10 minutes to 24 hours at a temperature of 80 to 150° C. before firing to remove the solvent embedded in the mixed solution. In this drying process, a drying method and a drying apparatus known to be commonly used may be used, and for example, drying may be performed using a heat source such as a hot fan, an oven, or a heating plate.

In addition, the sintering step refers to a series of processes in which the reactant is heated at a high temperature to produce a curable material, and may be performed in a temperature range of 300 to 900°C, preferably 500 to 750°C. If it is less than the above temperature range, the structure and crystallinity of the catalyst may change during the reaction, and if it exceeds the above temperature range, the interaction between atoms is too strong to increase the particle size or cause unnecessary side reactions.

In addition, the firing may be performed for 10 minutes to 10 hours, respectively. If the firing time is too short, the catalyst may not be completely fired, and if the firing time is too long, various side reactions such as carbonization of the catalyst may occur.

On the other hand, in the manufacturing method of the catalyst for glycerin dehydration reaction of the embodiment, the composite metal oxide is mixed with a coagulant including an inorganic metal sol and alcohol.

The coagulant is a material mixed to improve the mechanical strength of the composite metal oxide having low mechanical strength, and is 5 to 20% by weight of at least one inorganic metal sol selected from the group consisting of silica sol, alumina sol, titania sol, and zirconia sol; And at least one alcohol selected from the group consisting of glycerin, isopropyl alcohol, diacetone alcohol, methanol, ethanol, and propanol in the balance.

The inorganic metal sol may impart an effect of improving physical strength to the catalyst, and may contain 5 to 20% by weight. At this time, if the amount of the inorganic metal sol is less than 5% by weight, there is a limit that the physical strength is not sufficient for use as a catalyst. On the other hand, if the content exceeds 20% by weight, the bond between the inorganic fibers is too strong and physical The intensity can be weakened. Therefore, the inorganic metal sol is preferably used in an amount of 5 to 20% by weight.

Further, it is preferable to use silica sol or alumina sol as the inorganic metal sol.

In addition, the alcohol may play a role of uniformly mixing the catalyst and the forming solution, and controlling the viscosity of the catalyst. More specifically, among the alcohols, glycerin acts as a lubricant in the process of forming the catalyst. And, since isopropyl alcohol may play a role in controlling the viscosity of the catalyst, when the coagulant is mixed with isopropyl alcohol and glycerin, a catalyst for glycerin dehydration having excellent mechanical strength can be prepared.

In addition, the coagulant may further include one or more additives selected from the group consisting of bentonite, kaolin, kaolin, bohemite, and montmorillonite. Even if a small amount of additives such as bentonite and kaolin are added, physical strength can be greatly improved. At this time, the additive is preferably used in an amount of 20% by weight or less, preferably 15% by weight or less.

In addition, the composite metal oxide and the coagulant may be mixed in a weight ratio of 1:1 to 1:5, preferably 1:1 to 1:3. If too much of the coagulant is included compared to the composite metal oxide, there may be a problem that the activity of the catalyst is deteriorated. If too little is included, the effect of improving the physical strength of the catalyst is insignificant. It is preferred to be mixed.

Next, the mixture of the composite metal oxide and a coagulant is extruded. In the method for preparing the catalyst for glycerin dehydration reaction of the embodiment, the catalyst may be formed to have more excellent mechanical strength by extruding a mixture of a composite metal oxide and a coagulant, and the catalyst formed in this way comprises the composite metal oxide. Compared to the case where the catalyst is used as it is or supported on a carrier, the strength of the catalyst is superior, and even when applied to an actual pilot process, the reaction activity can be maintained for more than 140 hours without generating internal pressure.

At this time, the extrusion temperature is preferably 25 to 70 ℃, the screw rotation speed is in the range of 200rpm or more. If the extrusion temperature is less than 25°C, kneading may not occur properly, and if it exceeds 70°C, the alcohol component may evaporate, making it difficult to form a catalyst. Also, if the screw rotation speed is less than 200 rpm, smooth kneading does not occur.

And, after the step of extruding the mixture, the step of drying and firing the extrudate may be further included. The drying and firing of the extrudate may be applied without limitation, without limitation, the reaction conditions of the drying and firing in the manufacturing of the composite metal oxide described above, and the reaction apparatus.

On the other hand, according to another embodiment of the present invention, a method for producing acrolein comprising the step of reacting glycerin in the presence of a catalyst for glycerin dehydration prepared according to the above-described method for preparing a catalyst for glycerin dehydration can be provided. have.

As described above, the catalyst for the glycerin dehydration reaction prepared by mixing a complex metal oxide containing zirconium (Zr), tungsten (W) and phosphorus (P) with a coagulant of a specific composition and extruding it has high compressive strength, etc. It exhibits sufficient mechanical strength, and when used in the glycerin dehydration reaction, acrolein can be prepared in high yield and high conversion.

The amount of the catalyst for the glycerin dehydration reaction may be appropriately adjusted according to the amount and concentration of glycerin, and for example, 0.1 to 5 parts by weight, preferably 1 to 3 parts by weight, based on 100 parts by weight of glycerin per hour may be used.

In addition, the dehydration reaction may be performed at a temperature of 200 to 400°C. The dehydration reaction is an endothermic reaction, and in order to prepare acrolein with high conversion and selectivity, it is preferable to perform the reaction at a temperature within the above range.

According to the present invention, not only can improve the selectivity of acrolein by minimizing the generation of by-products, but also has sufficient mechanical strength, it is possible to provide a glycerin dehydration catalyst that can be applied in an actual process.

The invention will be described in more detail in the following examples. However, the following examples are merely illustrative of the present invention, and the contents of the present invention are not limited by the following examples.

[Production Example 1]: Preparation of composite metal oxide

_{ZrZn 0 .02 V 0.1 W 0. 1} H x (PO 4) 2 catalyst to 1 mole ratio of Zr, V and Zn molar ratio of the transition metal is from 0.02 and 0.1, respectively, in a molar ratio of P 2, It was prepared by adjusting the molar ratio of W to 0.1. To this end, 183.11 g of zirconium oxychloride, 3.414 g of zinc precursor (Zn(NO ₃ ) 6H ₂ O), 6.464 g of vanadium precursor (ammonium vanadate), 13.93 g of tungsten precursor (ammonium metatungstate hydrate) were mixed in 2250 ml of distilled water. After that, 132.05g of a precursor (ammonium phosphate: NH ₄ H ₂ PO ₄ ) was added.

Then, when a precipitate was formed after mixing, the mixture was heated to 90° C. and stirred for 3 days or more, and the precipitate was separated by filtration and washed with ethanol 3-5 times. The cake-shaped precipitate obtained after washing was dried in an oven at 100°C for 12 hours. The dried cake was baked in an air atmosphere at 700℃ for 6 hr to produce a composite metal oxide.

[Examples 1 to 5 and Comparative Examples 1 to 3]

30 g of the composite metal oxide prepared in Preparation Example 1 and 30-40 g of a coagulant having the composition of Table 1 were mixed, and the catalyst was extruded at room temperature and a screw rotation speed of 200 rpm or more using an extruder (SPG). In addition, the extrudate was dried in an oven at 100° C. for about a day, then molded into a cylindrical shape of 5 mm length, and fired at 700° C. for 6 hours to prepare a catalyst.

Silica sol
(wt%) Alumina sol
(wt%) glycerin
(wt%) IPA
(wt%) water
(wt%) Bentonite
(wt%) kaoline
(wt%) Example 1 15 17 68 Example 2 13 15 59 13 Example 3 13 15 59 13 Example 4 15 85 Example 5 22 16 62 Comparative Example 1 40 12 48 Comparative Example 2 30 14 56 Comparative Example 3 15 17 68

[ Comparative example 4]

remind The ZrZn ₀ produced in Production Example _{1 .02 V 0.1 W 0. 1 H} x (PO 4) 2 The composite metal oxide itself was used as a catalyst without a molding process.

[Comparative Example 5]

remind ZrZn _{0 .02} in the same manner as in Production Example _{1 V 0.1 W 0. 1 H x} (PO 4) 2 To prepare a composite metal oxide and additionally support 2.5 wt% of V, a vanadium precursor (ammonium vanadate) was sufficiently dissolved in distilled water, and then sufficiently dried using an evaporator to prepare a catalyst by an impregnation method. The sufficiently dried catalyst was subjected to a sintering process at 700° C. for 6 hr in an air atmosphere to prepare 2.5 wt% V/ZrZn _0.02 V _0.1 W _0.1 H _x (PO ₄ ) ₂ composite metal oxide.

[Experimental Example 1]: Compressive strength of catalyst for glycerin dehydration reaction

In order to measure the compressive strength of the glycerin dehydration catalyst prepared in Examples 1 to 5 and Comparative Examples 1 to 3, analysis was requested to PDIS, and a specimen having a length of 0.5 mm and a diameter of 0.5 mm using a Bose 5500 device The pressure when cracks were generated by this pressure was measured, and the average values of the data through three repeated experiments are summarized in Table 2 below.

Compressive strength (N) Example 1 29.05 Example 2 29.73 Example 3 55.74 Example 4 41.89 Example 5 41.55 Comparative Example 1 - Comparative Example 2 - Comparative Example 3 46.64

As shown in Table 2, the catalyst for glycerin dehydration reaction of Examples 1 to 5 prepared by mixing and extruding the composite metal oxide prepared in Preparation Example with a coagulant of a specific composition exhibited a compressive strength of 25N or more, and thus the actual process It can be seen that it has sufficient physical strength to be applied to, but in the case of Comparative Examples 1 and 2 prepared by mixing a large amount of silica sol at 30 wt% and 40 wt%, it did not have sufficient physical strength, so the impact strength was low enough not to be measured. In the actual experiment, various problems such as internal pressure occurred.

In addition, Comparative Example 3 is a case in which water is added to the coagulant, and since the catalyst is easily stiffened or dried, it is difficult to form the catalyst, and thus there are various limitations to use in an actual process.

[Experimental Example 2]: Conversion of glycerin, yield and selectivity of acrolein

Using the catalysts prepared in Example 1 and Comparative Examples 4 to 5, using a high-throughput screening (HTS) device designed to evaluate the performance with a small amount of catalyst in a short time under the conditions shown in Table 3 below. Acrolein was produced from glycerin, and the product was analyzed by GC in an in-situ state to calculate conversion, selectivity, and yield.

More specifically, the HTS device installed 16 reactors (outer diameter 9mm, length 25cm) to perform a large amount of catalytic experiment in the shortest time. In order to inject a liquid reactant at a constant rate, a pump (HPLC pump) was used. After being sent to the evaporator heater using, the vaporized reactant was supplied to the reactor at a constant rate together with nitrogen as a transport gas. The sampling operation was performed in a cooler set at a temperature of 0°C for the condensation process, and distilled water was added to a glass bottle to condense the reactants. The reaction was analyzed using gas chromatography (HP 6890N) connected online. A flame ionization detector (FID) was used and the column was HP-FFAP (25m X 0.32mm X 0.52mm).

The conversion rate of glycerin, the selectivity of acrolein, the selectivity of hydroxyl acetone, the selectivity of acetic acid, and the selectivity of residual by-products are shown in Table 4 below.

Here, the conversion ratio represents the ratio of glycerin converted to another compound, and the selectivity represents the ratio of each substance among the converted compounds. In addition, hydroxyl acetone and acetic acid are major by-products of the glycerin dehydration reaction, and the residual by-products refer to by-products other than hydroxyl acetone and acetic acid.

Glycerin dehydration reaction conditions Example 1 Comparative Examples 4 to 5 Reaction temperature 285 ℃ 280 ℃ Reaction pressure 0 barg Normal pressure Glycerin concentration 50 wt% 50 wt% Catalyst amount 250 g 250 g Feed feed speed 4-7.5 g/min 4-7.5 g/min GHSV 660-1642 h ^-1 11321 h ^-1 WHSV 3-6.4 h ^-1 45.8 h ^-1

Reaction time
(h) Glycerin conversion (%) Acrolein selectivity (%) Hydroxyl Acetone Selectivity (%) Acetic acid selectivity (%) Selectivity of residual by-products (%) Example 1 80 100 69.0 0 8.0 18.7 100 100 62.0 0 7.3 18.4 120 100 60.7 0 5.7 29.3 140 100 67.0 One 3.9 25.8 Comparative Example 4 69.38 75.66 4.36 15.38 Comparative Example 5 23.32 51.08 7.73 37.34

As shown in Table 3, the catalyst prepared under the conditions of Example 1 was tested in the actual pilot process step, and it was confirmed that it can be applied to the actual experiment.

As a result, it is noted that when glycerin is reacted using the catalyst of Example 1, acrolein can be produced with high selectivity and high purity from glycerin, and generation of by-products such as hydroxyl acetone and acetic acid can be suppressed. It can be confirmed from Table 4.

In addition, it was confirmed that the activity of the catalyst for glycerin dehydration reaction of Example 1 was maintained for 140 hours or more, and the cylindrical pellet shape of the catalyst was maintained even after the reaction.

Claims (9)

A composite metal oxide containing zirconium (Zr), tungsten (W), and phosphorus (P),
5 to 20% by weight of at least one inorganic metal sol selected from the group consisting of silica sol, alumina sol, titania sol, and zirconia sol; And at least one alcohol selected from the group consisting of glycerin, isopropyl alcohol, diacetone alcohol, methanol, ethanol, and propanol in the balance; mixing with a coagulant; And
Extruding the mixture obtained from the step of mixing the composite metal oxide and a coagulant; containing, a method for producing a catalyst for glycerin dehydration reaction.
The method of claim 1,
The composite metal oxide further comprises at least one transition metal selected from the group consisting of Zn, V, Fe, Mo, Ce, and Cu, a method for producing a catalyst for glycerin dehydration.
The method of claim 1,
The composite metal oxide is represented by the following Formula 1, a method of preparing a catalyst for glycerin dehydration:
[Formula 1]
Zr(M ₁ ) _p (M ₂ ) _q W _r P _s H _x O _y
In Formula 1,
M ₁ and M ₂ are each independently a transition metal selected from the group consisting of Zn, V, Fe, Mo, Ce and Cu,
p is a real number greater than 0 and not more than 1,
q is a real number from 0 to 1,
r is a real number greater than 0 and not more than 1,
s is a real number greater than 0 and not more than 10,
Each of x and y is independently a real number of 0.1 or more and 20 or less.
The method of claim 1,
The composite metal oxide,
Mixing a zirconium precursor, a tungsten precursor, and a phosphorus precursor; And
Drying and sintering the mixed solution obtained from the step of mixing the zirconium precursor, tungsten precursor, and phosphorus precursor; the method of manufacturing a catalyst for glycerin dehydration reaction.
The method of claim 1,
The coagulant method for producing a catalyst for glycerin dehydration reaction further comprises at least one additive selected from the group consisting of bentonite, kaolin, kaolin, bohemite, and montmorillonite.
The method of claim 1,
The method for producing a catalyst for glycerin dehydration reaction in which the composite metal oxide and the coagulant are mixed in a weight ratio of 1:1 to 1:5.
The method of claim 1,
A method for producing a catalyst for glycerin dehydration reaction, further comprising drying and firing the extrudate obtained from the extrusion step.
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