JPH0735341B2 - Catalyst for structural isomerization of olefin and method for structural isomerization of olefin - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catalyst for isomerizing olefins and a method for isomerizing olefins, and more particularly to a catalyst used for isomerizing olefins to form isomers having different structures and the catalysts using the catalyst. The present invention relates to a method for converting olefins into isomers having different structures.

[0002]

2. Description of the Related Art Conventionally, a geometric isomerization reaction of an olefin is carried out in the presence of an acidic catalyst and proceeds by a proton transfer between the olefins. This reaction does not require high temperature to proceed. However, as is well known, the structural isomerization reaction of an olefin is contacted and promoted under further extreme conditions by an olefin having no molecular chain and an acidic catalyst. Therefore, in the case of structural isomerization of olefins, the cation of the rukyru group carbon in the transient state of the isomerization reaction of the double bond must be transferred, and the desired substance is produced by the proton transfer step according to it. To do.

Conventionally, most of the catalysts used for structural isomerization use an aluminum carrier whose surface is modified with a halogen compound such as hydrogen bromide or butyl bromide. For example, 1988
U.S. Pat. No. 4,773 issued to Mr. Sun on October 18, 2010
No. 8,943, U.S. Pat. Nos. 4,654,463, issued to San on Mar. 31, 1987, and 1
Elsa et al., U.S. Pat. No. 4,4, Feb. 21, 984.
33,191. As is well known, the olefin isomerization reaction is limited to the thermal equilibrium state of the reactants. Most of the reports in the past patents or publications on structural isomerization catalysts have been produced from the treatment of halogenated compounds in order to maintain the activity and selectivity of the catalyst.

For example, the product of the structural isomerization of C4 olefins using these catalysts is isobutylene, which is a high octane gasoline ether compound,
That is, it is one of the reaction products of methyl tert-butyl ether (MTBE). The product of the structural isomerization of C4 olefins is also a reactant of the tertiary amyl group methyl ether (TAME) of high octane compounds.

[0005]

However, those catalysts have some drawbacks. For example, the cost of the catalyst is extremely high, yet it produces a large amount of waste and is difficult to dispose of.

[0006]

The method of catalysis used for the isomerization of olefins according to the present invention relates to a structural isomerization reaction of an olefin having 4 to 20 carbon atoms and an isomerization reaction involving a double bond. In order to isomerize into an olefin having the same number of molecular chains as carbon atoms, the catalyst undergoes the steps of impregnation, then calcination, and activation to give SKISO-II, the composition of which is
Aluminum oxide or an oxide of aluminum and boron, which promotes the isomerization reaction on the granules.

[0007]

In the structural isomerization reaction of olefins, olefins are converted into aluminum oxide-based catalysts SKISO-
II is used at a temperature of 200 ° C. to about 650 ° C. and a hydrogen or nitrogen olefin reactant is adjusted to 0 to 10 at an atmospheric pressure of 0.3 to 10 to effectively isomerize the olefin. That is, according to the method for producing a catalyst of the present invention, it is possible to proceed an effective structural isomerization reaction of an olefin without modifying the surface of the catalyst with a halogen compound.

[0008]

EXAMPLES Ortho-olefins are SKISO-based compounds of the present invention.
It is isomerized to an isoolefin under a II catalyst,
The support used in the catalyst is any crystalline form of aluminum oxide (except form α). When η or γ-aluminum oxide is used as a catalyst, relatively good results can be obtained, and the surface area is 40 m.
² / g to 500 m ² / g (measured by the nitrogen BET method). Further, other inorganic oxides can also be used as the catalyst of the present invention. However, the catalyst of the present invention must always contain at least 60 mol% γ-aluminum oxide or η-aluminum oxide. Other carriers, such as zeolites, can also be used. The catalyst may contain from 0.01 wt.% To about 20 wt.
It has a better reaction effect than when it contains 03 wt% to about 11 Wt% of amorphous aluminum oxide. further,
The catalyst may have a mixed composition of aluminum oxide and an oxide of phosphorus, boron, potassium or magnesium. Thus, the catalysts of the present invention can be formulated in combination. That is, a composition of aluminum oxide / γ- (or η-) aluminum oxide or aluminum oxide / MxOy / γ- (or η-) aluminum oxide is possible, where X and Y are 1 to 2 respectively. 1 to 5. Representative examples of M include boron, phosphorus, calcium, magnesium and the like. The composition of such a mixture oxide is always 0.01 wt% to 20 wt% of the total weight of the catalyst.
Must be in the range. A method for producing a catalyst of this type and a product of mixing in the structural isomerization reaction of ortho-olefin using the catalyst are described below. Typically, the structural isomerization reaction of the present invention isomerizes butene to isotylene and pentene to isopentene, and the reaction can be a geometric isomerization reaction or a structural isomerization reaction.

The method for producing the catalyst and the reaction of C4 and C5 olefins are as follows.

According to the present invention, the characteristics of the catalyst manufacturing method are as follows: The impregnation concentration of the particles of activated aluminum oxide is 0.0
It is an acidic aqueous solution of aluminum nitrate in the range of 01M to 1.0M. The aqueous solution may have a composition of aluminum nitrate and boric acid or calcium nitrate, and its concentration is 0.001M to 1.0M.

2. Impregnation is carried out at a temperature in the range of 20 ° C. to 90 ° C. for 0.5 hours to 20 hours.

3. After impregnation, the solid state catalyst is separated, and the temperature is in the range of 300 to 800 ° C for 2 hours to 3 hours in the atmosphere.
Bake for hours.

4. After calcination, the catalyst is from 300 ℃ to 800
It is activated for 2 to 30 hours in the atmosphere at ℃ or under nitrogen gas or hydrogen gas.

5. After activation, the catalyst is cooled to room temperature, thus obtaining the catalyst of the invention.

The above process is as shown in FIG. The physical properties of the catalyst prepared according to the present invention are 120-30.
BET surface area in the range of 0 m ² / g and 1.5 to 3.00
It has a particle size in the range of mm and a pore size in the range of 20 to 100Å.

In use, the reactant of the structural isomerization reaction contains an alkene containing at least 4 to 8 carbon atoms. The alkene may have a double bond inside or at the end, Alkenes, like alkanes, can have as many other hydrocarbons as there are carbon atoms. The special reactants used in the present invention are butene, or a mixture of butene and isobutylene, or a mixture of pentene and isopentene.
These fractions are usually refined in petroleum refining or petrochemical plants. For example, C in a naphtha cracking furnace is used.
5 stream, and MTBE mill C4 stream.

The olefin reactant may also contain an inert diluent, with the alkene content ranging from 10 wt% to 95 wt% of the reactant.

A typical example of the isomerization reaction using a catalyst is a geometric isomerization reaction or a structural isomerization reaction of a C4 or C5 olefin. Typical C4 olefins are 1-butene, cis-2-butene and trans-2.
-Butene and isobutylene. Typical C5 olefins are 1-pentene, cis-2-pentene, trans-2-pentene, 3-methyl-1-butene and 2-methyl-2-butene. The catalyst is 300 ℃ to about 800 ℃ under a gas containing hydrogen or nitrogen.
It is heated and regenerated at a temperature in the range. To maintain the activity of the catalyst, a gas mixture of hydrogen or nitrogen is mixed with the reaction mixture, with a molar ratio to the reaction mixture of 0 to 10 giving good results at 0 to 5.

The experimental apparatus and process are as follows.

The catalyst is placed in a fixed reactor with an inner diameter of 2.54 cm and a length of 30.5 c.
m. A few inert solid particles are placed at the bottom and top of the reactor and loaded with catalyst so that the reaction is evenly performed in the reactor. The experimental equipment includes a feed pump, heat transfer medium, product collection and sampling unit, mass meter, and temperature control system. The product is, as in the example, a Carlo Erba GC6000 VegaSe containing a FID detector.
Analyze using the Ries Unit gas phase analysis method. The analysis tube used for this is a capillary type tube.

[0021]

EXAMPLES Next, examples of the present invention will be described, but the examples of the present invention are not limited thereto.

Example 1 Preparation of Catalyst A catalyst is prepared as follows.

First, 1.0 g of aluminum nitrate is dissolved in water to prepare an aqueous solution having a molar concentration of 0.0267M.
This solution was impregnated with the γ-aluminum oxide support at 35 ° C. for 12 hours, and then the solid particles were taken out and calcined in air at a temperature of 550 ° C. for 12 hours.
The calcined catalyst is activated in air or hydrogen at 500 ° C. for 4 hours and finally cooled to room temperature to obtain the catalyst of the present invention. The catalyst thus obtained was 0.136 w
It is a catalyst composed of aluminum oxide with t% γ-aluminum oxide as a carrier.

Example 2 Preparation of Catalyst A catalyst having another composition is obtained in the following process.

0.3 g of aluminum nitrate and 0.5
g of boric acid was dissolved in water and the molar concentrations of aluminum nitrate and boric acid were 0.008 M and 0.
Make a 081M aqueous solution. After that, at 40 ℃,
This γ-aluminum oxide carrier is impregnated with the above aqueous solution for 20 hours. Further, the solid particles are separated and calcined at 550 ° C. for 12 hours, and the calcined catalyst is activated and cooled under the same conditions as in Example 1. The catalyst thus obtained has a composition of γ-aluminum oxide as a carrier, 0.041 wt% aluminum oxide, and 0.28 w.
It is a catalyst that bonds t% boron oxide to the side chain.

Example 3 Structural Isomerization Reaction A reactant for 1-pentene having a purity of 95%, but using 5.5 g of aluminum oxide / γ-aluminum oxide at 450 ° C., 1 atmospheric pressure and 0. The product distribution obtained under the reaction conditions of weight hourly space velocity (WHSV) of 0.8 hr-1 is 3.1 wt% 3-methyl-1-butene, 17.2 wt% trans-2-pentene, 9.1
wt% cis-2-pentene, 63.1 wt% 2-methyl-2-butene and 2-methyl-1-butene (or isopentene), 6.5 wt% pentanes and C4 (-) and 1 0.06% by weight of C6 hydrocarbon compound. The calculated conversions of orthopentene to isomers and the selectivity of isopentene are 0.737 and 0.856, respectively. When the content of pentenes in the product is measured, calorimetric calculation is performed, and equilibrium compositions of C5 olefins are compared, consistent results are obtained as shown in Table 1.

[0027]

[Table 1]

Example 4 Structural isomerization reaction Separately, a typical example of the structural isomerization reaction of orthobutene is carried out.

An ortho-butane isomer is produced by using 99.5 wt% of butene as a reaction product, and the catalyst is aluminum oxide / boron oxide / γ-aluminum oxide.
The distribution of the products obtained under the reaction conditions of 1.0 ° C., 1 atmospheric pressure, and WHSV of 1.0 hr −1 is 15.4 wt% 1-butene, 23.9 wt% trans-2-butene, 17.
1 wt% cis-2-butene, 32.9 wt% isobutylene, 4.8 wt% butane and C3 (−) and 5.9 wt% C5 (+) hydrocarbon compounds. The calculated values of orthobutene isomerization and isobutylene selectivity are 0.436 and 0.755, respectively. When the content of butenes in the product is measured, calorimetric calculations are performed, and equilibrium compositions of C4 olefins are compared, consistent results are obtained as shown in Table 2.

[0030]

[Table 2]

Example 5 Structural isomerization reaction The reaction product was 1-pentene having a purity of 95 wt%, and the catalyst was 5.5 g of aluminum oxide / γ-aluminum oxide. Operating conditions are 1 atmospheric pressure, 0.81 hr-1 WH
SV and different temperatures, eg 200 ° C, 250 ° C, 3
The temperature is 00 ° C, 350 ° C, 400 ° C, and 450 ° C. The composition of the product obtained from each condition is as shown in Table 3.

[0032]

[Table 3]

Example 6 Structural isomerization reaction 1-butene having a purity of 99.5 wt% was used as a reaction product, and aluminum oxide / γ-aluminum oxide was used as a catalyst. Operating conditions are 1 atmospheric pressure, 1.0 WHSV, 250
C., 300.degree. C., 350.degree. C., 400.degree. C. and 500.degree. C. different temperature conditions. The production rate of butene under each temperature condition is not equal, and the production rate of isobutylene at 400 ° C. increases rapidly. The composition of the product under each condition is as shown in Table 4.

[0034]

[Table 4]

When operating conditions other than those mentioned above, almost the same results are obtained.

The outline and features of the present invention have been described above with reference to specific examples. The present invention can be applied to various uses, but the embodiments described here are not outside the scope of the present invention. These embodiments are within the scope of application and the product names mentioned in the description should not be taken.

[0037]

As described above, the present invention can be used to improve the quality of gasoline. Further, it is possible to reduce the cost and provide a new catalyst that advances the isomerization reaction of ortho-olefin.

According to the invention, the characteristic isomerization reaction of olefins having 4 to 20 carbon atoms is described in SKISO-I.
It is formed by the I catalyst and is promoted by accelerating the reaction of the aluminum oxide and the aluminum and boron oxide on the γ or η aluminum oxide granules. The major product, the olefin isomer, is close to the equilibrium composition of C4 or C5 olefins or other olefins of carbon number. The activity and selectivity of the catalyst used during the reaction of the present invention are superior to those of other halogenated γ-aluminum oxide catalysts containing γ-aluminum oxide brominated or fluorinated as a main component.

[Brief description of drawings]

FIG. 1 is a flowchart showing a method for producing a catalyst of the present invention.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Khun-Yoon Sai Taiwan, Taipei, Yong-Wa Road, Section 1, Number 83

Claims (8)

[Claims] 1. A γ- or η-aluminum oxide base is impregnated with an aqueous solution of aluminum nitrate or an aqueous solution of aluminum nitrate and boric acid at a concentration of 0.001 M to 1.0 M at ambient temperature for 0.5 to 20 hours. The aqueous solution is removed, the solid particles are dried at 140 to 160 ° C. for 3 to 5 hours, and then calcined and the calcined product is dried at 300 ° C.
Amorphous aluminum oxide supported on pellets of γ- or η-aluminum oxide which was activated by heating at a temperature of ˜800 ° C. for 2 to 30 hours and then cooled, or of γ- or η-aluminum oxide. Pellet-supported catalyst for structural isomerization of olefins consisting of amorphous aluminum oxide and boric acid. 2. The catalyst according to claim 1, wherein the content of all amorphous oxides is in the range of 0.01 to 20.0% by weight, based on the total weight of the catalyst. 3. BET in the range of 120 to 300 m ² / g
Surface area and particle size in the range of 1.5-3.0 mm,
A pore size in the range of 20 to 100Å.
The catalyst according to 1. 4. The presence of a catalyst based on an isomerization state, wherein the catalyst is an aluminum oxide base and the feed is at least one olefin having a total content in the range of 8.0 to 99.5% by weight. A method for structural isomerization of olefins in which a structural isomerization reaction of a feed material having 4 to 20 atoms per molecule and a double bond isomerization reaction are carried out. 5. The olefin is a C4 olefin,
The method of claim 4, wherein the product is isobutylene. 6. The olefin is a C5 olefin,
The method of claim 4, wherein the product is isopentane. 7. The operating conditions of isomerization reaction of C4 olefin are reaction temperature of 100 ° C. to 650 ° C., body pressure of 1 to 10 and WHSV of 0.1 to 15.0 hr −1.
And a molar ratio of hydrogen or nitrogen to the reaction mixture within the range of 0 to 10. 8. The operating conditions of the isomerization reaction of C5 olefin are reaction temperature of 100 ° C. to 650 ° C., body pressure of 1 to 10 and WHSV in the range of 0.1 to 10.0 hr-1.
And a molar ratio of hydrogen or nitrogen to the reaction mixture in the range of 0-10.