KR101657987B1 - Niobium-based amorphous catalyst for dehydration reaction of glycerol - Google Patents
Niobium-based amorphous catalyst for dehydration reaction of glycerol Download PDFInfo
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- KR101657987B1 KR101657987B1 KR1020150065435A KR20150065435A KR101657987B1 KR 101657987 B1 KR101657987 B1 KR 101657987B1 KR 1020150065435 A KR1020150065435 A KR 1020150065435A KR 20150065435 A KR20150065435 A KR 20150065435A KR 101657987 B1 KR101657987 B1 KR 101657987B1
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- niobium
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- glycerol
- dehydration reaction
- acrolein
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/16—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
- B01J23/20—Vanadium, niobium or tantalum
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J29/00—Catalysts comprising molecular sieves
- B01J29/82—Phosphates
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/0009—Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst
- B01J37/0018—Addition of a binding agent or of material, later completely removed among others as result of heat treatment, leaching or washing,(e.g. forming of pores; protective layer, desintegrating by heat)
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C47/00—Compounds having —CHO groups
- C07C47/20—Unsaturated compounds having —CHO groups bound to acyclic carbon atoms
- C07C47/21—Unsaturated compounds having —CHO groups bound to acyclic carbon atoms with only carbon-to-carbon double bonds as unsaturation
- C07C47/22—Acryaldehyde; Methacryaldehyde
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/582—Recycling of unreacted starting or intermediate materials
Abstract
The present invention relates to a niobium amorphous catalyst used in an acrolein production process by dehydration reaction of glycerol, a process for producing the amorphous catalyst, and a process for producing acrolein using the amorphous catalyst.
Description
The present invention relates to a niobium amorphous catalyst used in an acrolein production process by dehydration reaction of glycerol, a process for producing the niobium amorphous catalyst, and a process for producing acrolein using the niobium amorphous catalyst.
Acrolein is used as an important intermediate in a wide range of chemical industries, including acrylic acid, methionine, superabsorbent polymers, and detergents.
Acrolein is produced mainly through the partial oxidation of propylene, which is a petrochemical product. This process is greatly influenced by oil prices and releases a large amount of carbon dioxide in the atmosphere, which limits commercial use.
The dehydration reaction of glycerol is known as another production method of acrolein, and is mainly carried out using an acid catalyst. If a liquid acid catalyst (homogeneous catalyst) such as sulfuric acid or phosphoric acid is used as the acid catalyst, separation with the reactant and waste acid treatment must be performed, the catalyst can not be reused, and the reactor may be corroded. As a catalyst for the dehydration reaction of glycerol, a solid acid catalyst (heterogeneous catalyst) is mainly used.
Currently, solid acid catalysts for the dehydration reaction of glycerol are being actively developed. Non-Patent Document 1 discloses a method of producing a crystalline NbPO 4 solid acid catalyst by using niobium chloride (NbCl 5 ) and phosphoric acid (H 3 PO 4 ), and a method of producing the crystalline NbOPO 4 4 < / RTI > solid acid catalyst for dehydration of glycerol to produce acrolein. However, the NbPO 4 solid acid catalyst disclosed in the aforementioned non-patent document 1 can be classified as a crystalline catalyst, which is different from the amorphous catalyst according to the present invention in the preparation method or the catalyst composition.
An object of the present invention is to provide a niobium amorphous catalyst used in acrolein production reaction by dehydration reaction of glycerol.
Another object of the present invention is to provide a process for preparing a niobium amorphous catalyst which improves catalytic activity by performing steam pretreatment before calcining a solid product prepared by impregnation.
Still another object of the present invention is to provide a method for producing acrolein by performing a dehydration reaction of glycerol in the presence of the above-mentioned niobium amorphous catalyst.
In order to accomplish the above object, the present invention provides a method of manufacturing a semiconductor device, comprising: (A) a niobium (Nb) precursor; And (B) a phosphoric acid (H 3 PO 4); And is characterized by a niobium amorphous catalyst for dehydration reaction of glycerol which is prepared by pre-treating at 250 to 350 ° C in an atmosphere of steam and argon.
(I) adding a niobium (Nb) precursor and phosphoric acid (H 3 PO 4 ) to water and stirring the mixture at a temperature of 40 to 60 ° C to prepare a suspension; Ii) drying the suspension at 80 to 120 DEG C to obtain a solid product; Iii) pre-treating the solid product at 250 to 350 DEG C in a steam and argon atmosphere; And iv) calcining the solid product at 300 to 450 ° C in an air atmosphere to obtain an amorphous catalyst; The present invention provides a method for producing a niobium amorphous catalyst for dehydration reaction of glycerol.
The present invention also provides a method for producing acrolein by dehydration reaction of glycerol in the presence of the above-mentioned niobium amorphous catalyst.
In the present invention, the steam pre-treatment is carried out before firing the catalyst, thereby solving the problem of reducing the specific surface area of the catalyst generated during the production of the conventional solid acid catalyst.
Therefore, the catalyst of the present invention has an increased specific surface area as compared with a conventional solid acid catalyst, thereby being used as a catalyst for dehydration reaction of glycerol which proceeds in a gas phase reaction, thereby improving the stability and performance of the catalyst.
Figure 1 shows the XRD analysis of a niobium amorphous catalyst.
Figure 2 shows the It is a graph showing a result of analysis of the NH 3 -TPD niobium-based amorphous catalyst.
FIG. 3 is a graph comparing the activity of catalysts prepared according to Examples and Comparative Examples. FIG.
The present invention relates to a niobium amorphous catalyst used for producing acrolein by dehydration reaction of glycerol, and a process for producing the same.
The niobium amorphous catalyst of the present invention comprises (a) a precursor of an active metal and (b) phosphoric acid (H 3 PO 4 ), and is pre-treated at 250 to 350 ° C. in a steam and argon atmosphere before firing do.
[catalyst]
(a) an activated metal
The solid acid catalyst of the present invention comprises a niobium (Nb) metal element as an active metal.
In constructing the catalyst of the present invention, the active metal is included in the form of a precursor compound. Specific examples of the precursor of the active metal include niobium halides such as niobium fluoride (NbF 5 ), niobium chloride (NbCl 5 ), and niobium bromide (NbBr 5 ); Niobium alkoxide such as niobium ethoxide; And niobium oxide such as niobium oxide (Nb 2 O 5 ) may be used. Among them, niobium oxide (Nb 2 O 5 ) in powder form is more preferably used.
(b) phosphoric acid (H 3 PO 4)
In the present invention, phosphoric acid is included to enhance the acid property of the solid acid catalyst. The phosphoric acid combines with the active metal to increase the amount of acid sites, thereby increasing the yield of acrolein. In addition, phosphoric acid is a crystalline solid material and has desirable properties that are well soluble in water solvents used in the production of solid acids.
In constituting the catalyst of the present invention, the phosphoric acid is contained in the range of 10 to 50 wt% with respect to the weight of the niobium (Nb) metal element contained in the niobium precursor. If the content of phosphoric acid is less than 10% by weight, the effect of strengthening the acid property of the catalyst is weak, resulting in poor catalytic activity. On the other hand, if the content of phosphoric acid exceeds 50% by weight, Catalyst deactivation is promoted and the yield of acrolein is reduced.
[Production method of catalyst]
The niobium amorphous catalyst of the present invention can be produced based on impregnation method. Specifically, the process for preparing a niobium amorphous catalyst according to the present invention comprises the steps of (i) adding a niobium (Nb) precursor and phosphoric acid (H 3 PO 4 ) to water and stirring at 40 to 60 ° C to prepare a suspension; Ii) drying the suspension at 80 to 120 DEG C to obtain a solid product; Iii) pre-treating the solid product at 250 to 350 DEG C in a steam and argon atmosphere; And iv) calcining the solid product at 300 to 450 ° C in an air atmosphere to obtain an amorphous catalyst; .
The method for producing the catalyst according to the present invention will be described in more detail as follows.
First, i) a niobium (Nb) precursor and phosphoric acid (H 3 PO 4 ), which are active metals, are added to water at a predetermined content ratio defined above and stirred to obtain a suspension. At this time, the stirring is sufficiently carried out while maintaining the temperature at 40 to 60 ° C.
And ii) drying the suspension to remove the solvent to obtain a solid product. In this case, the drying is carried out at 80 to 120 ° C for 12 to 18 hours, and it is also possible to adjust the drying temperature and time within a range that does not affect catalytic activity for complete drying of the solid product.
And iii) the dried solid product is pre-treated at 250-350 ° C in a steam and argon atmosphere. At this time, if the pretreatment temperature is lower than 250 ° C., the effect of steam pretreatment may not be sufficiently expected. If the temperature exceeds 350 ° C., the phosphoric acid carried on the active metal may be lost. In the present invention, steam pre-treatment is carried out at a temperature of 250 to 350 ° C. while flowing argon carrier gas before firing, thereby increasing the specific surface area of the solid product and finally increasing the catalytic activity in the dehydration reaction of glycerol Can be obtained. That is, when the hydrogen / argon pretreatment method or the methane / helium method is used as a general pretreatment method, the effect of increasing the catalytic activity is not shown in comparison with the pretreatment method of the present invention, whereas in the present invention, It is possible to obtain an extraordinary effect in which the increase of the intermediate acid point and the increase of the specific surface area are obtained.
In the present invention, argon is used as a carrier gas in the steam pretreatment process, and the flow rate thereof is maintained at 10 to 20 cc / min.
And iv) calcining the pretreated solid product in an air atmosphere at a temperature of 300 to 450 ° C. for 3 to 4 hours to obtain an amorphous catalyst. If the calcination temperature is lower than 300 ° C., the catalyst may be subjected to dehydration reaction of glycerol to change the structure of the catalyst during the reaction. If the calcination temperature exceeds 450 ° C., the crystallinity of the active metal may change. As a result, Thereby degrading performance. The calcined solid product is pulverized to an average particle diameter of about 150 to 300 mu m using a ball mill or the like to obtain a powdery amorphous catalyst.
The catalyst of the present invention prepared through the above-described production method is an amorphous solid acid catalyst (see FIG. 1) and has a specific surface area of 35 to 45
In addition, NH 3 -TPD analysis of the niobium amorphous catalyst of the present invention shows that acid sites (300-400 ° C.) beneficial for the dehydration reaction of glycerol are mainly distributed (see FIG. 2). Therefore, the niobium amorphous catalyst of the present invention is useful as a catalyst for producing acrolein by dehydration reaction of glycerol.
[Dehydration reaction of glycerol]
The present invention is also characterized in that acrolein is produced by dehydration reaction of glycerol in the presence of the above-mentioned niobium amorphous catalyst.
The dehydration reaction of glycerol according to the present invention proceeds in a vapor phase reaction while flowing a carrier gas. At this time, an inert gas selected from argon (Ar), nitrogen (N 2 ), helium (He) or the like is used as the carrier gas and flows at a flow rate of 10 to 20 cc / min
The temperature of the dehydration reaction is suitably 250 to 350 ° C in view of the boiling point of glycerol. When the reaction temperature is lower than 250 ° C, the catalyst life may be shortened due to polymerization with glycerol or reaction products or deposition of reaction materials on the catalyst surface And if it exceeds 350 ° C, the concurrent reaction or the sequential reaction increases, and the yield of the desired acrolein may be lowered.
The pressure of the dehydration reaction is not particularly limited, but it is preferably 10 atm or less, more preferably 5 atm or less under absolute pressure. Under high pressure conditions, the vaporized glycerol may be re-liquefied and the lifetime of the catalyst due to carbon deposition may be shortened.
Glycerol, which is a raw material for the dehydration reaction, is readily available as an aqueous glycerol solution and is fed at a flow rate of 3 to 6 mL / h. At this time, the aqueous glycerin solution may be used in a concentration range of 5 to 90% by weight, preferably 10 to 60% by weight. If the concentration of the glycerol aqueous solution is excessively high, not only does it require a great deal of energy to vaporize glycerol, but also side products are produced.
The present invention will now be described in more detail with reference to the following examples, which should not be construed as limiting the scope of the invention.
[Examples] Preparation of Catalyst
Examples. Preparation of steam pre-treated niobium amorphous catalyst
1 g of niobia (Nb 2 O 5 .nH 2 O) and 0.3 g of phosphoric acid (H 3 PO 4 ) were added to 50 mL of water and vigorously stirred for 4 hours while maintaining the temperature at 50 ° C. The suspension thus obtained was dried at 100 DEG C for 12 hours to remove the water solvent. The solid product obtained through the drying process was pulverized in a ball mill to prepare a powder having an average particle size of 200 탆. 0.5 g of powdery solid product was placed in a 8.8 mm diameter quartz reactor and argon was flowed at a rate of 10 cc / min and maintained at 300 < 0 > C. Distilled water was supplied to the reactor at a flow rate of 0.083 mL / min for 4 hours while maintaining the internal temperature of the reactor at 300 캜. The steam was passed through the catalyst layer and the solid product was preliminarily contacted with steam. The steam pretreated solid product was calcined in an air atmosphere at 400 ° C for 4 hours to prepare a desired niobium amorphous catalyst.
The niobium amorphous catalyst prepared in the above example had a specific surface area of 43.28
Further, Fig. 1 is a result of XRD analysis of the catalyst prepared by the example. According to the results of XRD analysis, it can be seen that the catalyst prepared in the above example is amorphous which does not show crystallinity.
Comparative Example. Preparation of catalysts without steam pretreatment
1 g of niobia (Nb 2 O 5 .nH 2 O) and 0.3 g of phosphoric acid (H 3 PO 4 ) were added to 50 mL of water, and stirred vigorously for 4 hours while maintaining the temperature at 70 ° C. The suspension thus obtained was dried at 100 DEG C for 12 hours to remove the water solvent. The solid product obtained through the drying process was calcined in an air atmosphere at 400 ° C. for 3 hours and then pulverized in a ball mill to prepare a powdery catalyst having an average particle size of 200 μm.
The niobium amorphous catalyst prepared in the Comparative Example had a specific surface area of 8.694
FIG. 2 shows results of NH 3 -TPD analysis of the catalysts prepared in Examples and Comparative Examples. 2 shows that the catalysts of the examples had a wider range of acidity distribution and a larger amount of acid sites than the catalyst of the comparative example, and that the intensity of the intermediate acid was increased in particular. In the case of the production of acrolein by the gas-phase dehydration of glycerol, the acrolein yield is low when the intensity of the strong acid point is too strong as in the catalyst of the comparative example, which results in accelerating the carbon deposition on the catalyst surface and lowering the catalytic activity.
[Experimental Example] Synthesis of acrolein from glycerol
Experimental example. Manufacture of acrolein
0.4 g of each of the catalysts prepared in the above Examples and Comparative Examples was introduced into a quartz reactor having a diameter of 8.8 mm and a glycerol aqueous solution having a concentration of 10% by weight was injected at a rate of 5 mL / h. After the temperature of the reactor was elevated to 310 ° C., glycerol and argon were reacted with 10 cc / min of argon (Ar) gas as a carrier gas in the reactor while the temperature inside the reactor was kept constant at 310 ° C., .
FIG. 3 shows the results of comparing the activity of each catalyst in the dehydration of glycerol. 3, it can be seen that the catalysts of the examples had a higher conversion of glycerol but a higher yield of acrolein than the catalyst of the comparative example.
[Reference Example] Comparison of the activity of the niobium catalyst prepared by the pretreatment method
Amorphous catalysts were prepared by changing the pretreatment conditions for the solid products before air calcination as shown in Table 1 below. Further, synthesis reaction of acrolein from glycerol was carried out by the same method as described in the above Experimental Example using each of the prepared catalysts. The results are shown in Table 1 below.
(M < 2 > / g)
volume
(Cm3 / g)
(%)
(%)
yield(%)
(° C)
(h)
Claims (8)
Ii) drying the suspension at 80 to 120 DEG C to obtain a solid product;
Iii) pre-treating the solid product with steam at a temperature of 250 to 350 DEG C while flowing an argon carrier gas at a flow rate of 10 to 20 cc / min; And
Iv) calcining and calcining the solid product at 300-450 ° C in an air atmosphere to obtain an amorphous catalyst;
Wherein the molar ratio of the niobium amorphous catalyst to the niobium amorphous catalyst is in the range of 10 to 50 wt%.
Wherein the niobium (Nb) precursor is selected from the group consisting of halides, alkoxides and oxides of niobium (Nb).
A process for producing a niobium-based catalyst, characterized in that 10 to 50% by weight of phosphoric acid is used in relation to the weight of the niobium (Nb) metal element contained in the niobium precursor.
Wherein the dehydration reaction proceeds in a gas phase reaction at 250 to 350 占 폚.
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| KR1020150065435A KR101657987B1 (en) | 2015-05-11 | 2015-05-11 | Niobium-based amorphous catalyst for dehydration reaction of glycerol |
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| KR1020150065435A KR101657987B1 (en) | 2015-05-11 | 2015-05-11 | Niobium-based amorphous catalyst for dehydration reaction of glycerol |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100984942B1 (en) * | 2010-07-27 | 2010-10-01 | 전북대학교산학협력단 | Catalysts for using in the production of trichlorosilane by the hydrodechlorination of silicon tetrachloride and process for preparing the same |
| KR101268459B1 (en) | 2011-04-14 | 2013-06-04 | 서울대학교산학협력단 | Catalyst for the dehydration of glycerol to acrolein and preparing method of the same |
| KR20140053209A (en) | 2011-07-29 | 2014-05-07 | 닛뽄 가야쿠 가부시키가이샤 | Catalyst for manufacture of acrolein and acrylic acid by means of dehydration of glycerin, and manufacturing method for same |
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2015
- 2015-05-11 KR KR1020150065435A patent/KR101657987B1/en active IP Right Grant
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100984942B1 (en) * | 2010-07-27 | 2010-10-01 | 전북대학교산학협력단 | Catalysts for using in the production of trichlorosilane by the hydrodechlorination of silicon tetrachloride and process for preparing the same |
| KR101268459B1 (en) | 2011-04-14 | 2013-06-04 | 서울대학교산학협력단 | Catalyst for the dehydration of glycerol to acrolein and preparing method of the same |
| KR20140053209A (en) | 2011-07-29 | 2014-05-07 | 닛뽄 가야쿠 가부시키가이샤 | Catalyst for manufacture of acrolein and acrylic acid by means of dehydration of glycerin, and manufacturing method for same |
Non-Patent Citations (2)
| Title |
|---|
| - PO4/Nb2O5 촉매 상에서 글리세롤의 기상 탈수반응, 전남대학교 대학원 석사학위논문, 2015.02. * |
| "Vapor Phase Dehydration of Glycerol to Acrolein Over NbOPO4 catalysts", J Chem Technol Biotechnol 2014; 89: 1890-897 |
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