JPH09117666A - Oxychlorination catalyst for ethylene - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent catalytic particles from becoming coagulated with each other and make the life of a catalyst long, and further, facilitate the operating steps at the time of chemical reaction. SOLUTION: This oxychlorination catalyst for ethylene is composed of a physical mixture of an alumina particle (A) containing copper chloride with a Cu content falling within the range of 8-15wt.%, the weight ratio of Cu/Al2 O3 falling within the range of 0.10-0.22, and the product of Cu/Al2 O3 (weight ratio) and a specific surface area (m<2> /g) equal to at least 30m<2> /g, and an alumina particle (B) with a specific surface area of at least 160m<2> /g.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a catalyst for oxychlorination of ethylene in a fluidized bed. More specifically, it has excellent catalytic activity and life, and is easy to operate during the reaction when the catalyst is used. The present invention relates to a fluidized catalyst for ethylene oxychlorination.

[0002]

BACKGROUND ART Conventionally, as a catalyst for oxychlorination of hydrocarbons (especially ethylene) in a fluidized bed, a solid catalyst in which copper chloride is supported on various carriers has been widely used. Alumina is commonly used. For example, in JP-B-45-21924, a catalyst is prepared by adding a CuCl ₂ aqueous solution to activated alumina powder produced by the Bayer method, mixing and filtering the cake, and drying the resulting cake at 100 to 120 ° C. in air. ing. The Cu content of this catalyst is 3.5 to 7% by weight.
Since this catalyst uses activated alumina powder manufactured by the Bayer method as a carrier, it has a small specific surface area and a small pore volume, and also has a low Cu content, so the catalytic activity is low, and the catalyst particles agglomerate during use. There was a problem.

Further, Japanese Patent Publication No. 43-3761 discloses that
Finely divided activated alumina with copper chloride as Cu 4.7 to 14.
Impregnated catalysts prepared by impregnation with 2% by weight are described. The catalyst prepared by the dipping method or the impregnation method has a limited amount of supported Cu and a small specific surface area of the catalyst, so that the activity and selectivity of the catalyst are low, and the catalyst particles agglomerate during the reaction. There was a problem that it became easier and the driving operation during reaction was difficult. In addition, C was added to alumina hydrogel composed of sodium aluminate and aluminum sulfate.
Post-deposition catalysts catalyzed by the addition of uCl ₂ have a similar tendency.

JP-B-45-39616 discloses a method for producing a fluidized catalyst for ethylene oxychlorination which has an appropriate specific gravity and is excellent in particle shape, abrasion resistance and catalytic activity. . The method for producing this catalyst is
The gel-like coprecipitate obtained by mixing a hydrochloric acid solution of cupric chloride and a sodium aluminate solution is aged, then spray-dried to form fine spheres, which are further calcined. The catalyst prepared in this manner can increase the amount of supported Cu, has a large specific surface area of the catalyst, has an appropriate specific gravity, particle shape and excellent abrasion resistance, and has high catalytic activity. have. However, there is room for improvement in terms of catalyst life, difficulty of operation due to aggregation of catalyst during reaction, and the like.

[0005]

It is an object of the present invention to provide a catalyst which is excellent in catalytic activity, selectivity and catalyst life, and which does not cause agglomeration of catalyst particles to each other when the catalyst is used in a fluidized bed and which can be easily operated during the reaction. It is intended to be provided.

[0006]

SUMMARY OF THE INVENTION A fluidized catalyst for ethylene oxychlorination according to the present invention has a Cu content in the range of 8 to 15% by weight and a Cu / Al ₂ O ₃ weight ratio of 0.10 to 0.2.
2 and the copper chloride-containing alumina particles (A) having a product of Cu / Al ₂ O ₃ (weight ratio) and specific surface area of 30 m ² / g or more, and a specific surface area of 160 m ² / g or more. It is characterized by being physically mixed with alumina particles (B).

The alumina of the copper chloride-containing alumina particles (A) is preferably amorphous alumina. Further, the copper chloride-containing alumina particles (A) and alumina particles (B)
The mixing ratio (B) / (A) in the physical mixture of is preferably in the range of 3/97 to 50/50 by weight.

[0008]

DETAILED DESCRIPTION OF THE INVENTION The flow catalyst for ethylene oxychlorination according to the present invention will be specifically described below.

The fluidized catalyst for ethylene oxychlorination according to the present invention is used for oxychlorination of ethylene in a fluidized bed, and comprises a mixture of copper chloride-containing alumina particles (A) and alumina particles (B). ing.

The copper chloride-containing alumina particles (A) have a Cu content in the range of 8 to 15% by weight. When the Cu content is less than 8% by weight, the activity of the catalyst may be reduced, and when the Cu content is more than 15% by weight, the fluidity of the catalyst may deteriorate, and May be difficult to drive. Preferably, Cu is 10 to 1
It is contained in an amount of 4% by weight. In addition, C in the present specification
The u content is a value on a wet basis.

The copper chloride-containing alumina particles (A) are C
The weight ratio of u / Al ₂ O ₃ is in the range of 0.10 to 0.22. Since the copper-containing alumina particles chloride (A) is may vary the amount of chlorine by firing temperature of the particles, also the Cu content by the inclusion of the third component may also be varied, in this specification, Al ₂ O The weight ratio of Cu to ₃ is also specified. When the weight ratio of Cu / Al ₂ O ₃ is smaller than 0.10, the active component is small and the catalytic activity is low, and when it is larger than 0.22, the specific surface area of the catalyst is extremely small. Therefore, the activity is lowered and the fluidity of the catalyst is deteriorated. The weight ratio of Cu / Al ₂ O ₃ is preferably in the range of 0.12 to 0.20.

Further, the copper chloride-containing alumina particles (A)
Has an average particle diameter of 30 to 120 μm, preferably 50 to 1
00 μm, the bulk density is 0.60 to 1.40 g / ml, preferably 0.80 to 1.20 g / ml, and the specific surface area is 18
It is preferably 0 m ² / g or more, and more preferably 200 m ² / g or more. Such copper chloride-containing alumina particles (A)
Exhibits excellent wear resistance when used in a fluidized bed.

Furthermore, the copper chloride-containing alumina particles (A) have a Cu / Al ₂ O ₃ (weight ratio) and a specific surface area (m ²
/ G) is 30 m ² / g or more, preferably 35 m ² / g
That is all.

Here, the specific surface area of the copper chloride-containing alumina particles (A) is a value measured by the BET method. In the present invention, the oxychlorination reaction of ethylene is shown below, from ethylene to 1,2-dichloroethane (EDC)
Is generated.

C ₂ H ₄ + 2HCl + 1 / 2O ₂ → C ₂ H
₄ Cl ₂ + H ₂ O According to the research conducted by the present inventors, 1,2-dichloroethane (ED
The larger the Cu / Al ₂ O ₃ weight ratio is,
Also, the higher the specific surface area of the catalyst, the greater the amount. That is,
The activity of the catalyst depends on the Cu / Al ₂ O ₃ weight ratio and the specific surface area (m ²
/ G) product. Therefore, Cu / Al ₂ O
The product of ₃ (weight ratio) and specific surface area (m ² / g) is 30 m ² /
If it is smaller than g, the activity of the catalyst may be low. In the present invention, the specific surface area of the copper chloride-containing alumina particles (A) is 180 m ² / g or more, preferably 2
It is preferably at least 00 m ² / g.

Such copper chloride-containing alumina particles (A)
Can be prepared, for example, by the method described in JP-B-45-39616. That is, a hydrochloric acid aqueous solution of cupric chloride and an aqueous solution of sodium aluminate are reacted to form a gel coprecipitate, the gel coprecipitate obtained is aged, and then spray-dried to form fine spherical particles, The particles are washed, dried and calcined to obtain copper chloride-containing alumina particles (A). The copper chloride-containing alumina particles (A) obtained by such a method show a diffraction pattern of amorphous alumina by X-ray diffraction. Amorphous alumina is particularly preferable because it has a large specific surface area. The copper chloride-containing alumina particles (A) in the present invention are not limited to the above-mentioned manufacturing method, and any manufacturing method may be used as long as it has desired characteristics.

Next, the alumina particles (B) will be described. From the viewpoint of fluidity of the catalyst, it is desirable that the alumina particles (B) have properties such as particle diameter and bulk density that are similar to those of the above-mentioned copper chloride-containing alumina particles (A). That is,
The average particle size of the alumina particles (B) is 30 to 120 μm.
m, and the bulk density (CBD) is from 0.60 to
It is preferably in the range of 1.40 g / ml. The specific surface area of the alumina particles (B) is preferably large, particularly 160 m ² / g or more, preferably 200 to 40.
The range of 0 m ² / g is preferable. The specific surface area is 16
If it is less than 0 m ² / g, the ability to capture copper scattered from the copper chloride-containing alumina particles (A) during the reaction may be poor.

The alumina particles (B) in the present invention may contain a second component other than alumina, for example, silica or the like. However, the content of alumina is 50% by weight or more, preferably 80% by weight or more,
It is more preferable that the content is 95% by weight or more. The alumina particles (B) are preferably γ-alumina.

Such alumina particles (B) exhibit excellent wear resistance when used in a fluidized bed. A fluidized catalyst for ethylene oxychlorination according to the present invention comprises the above-mentioned copper chloride-containing alumina particles (A) and alumina particles (B).
It consists of a physical mixture with, but the mixing ratio (B) / (A)
Is preferably in the range of 3/97 to 50/50 by weight.

In the present invention, the copper chloride-containing alumina particles (A) and the alumina particles (B) are mixed and used as a fluidized bed catalyst for ethylene oxychlorination to prevent the catalyst particles from aggregating. It is possible,
The life of the catalyst becomes long, and the operation during the reaction becomes easy.

When the mixing ratio (B) / (A) of the copper chloride-containing alumina particles (A) and the alumina particles (B) is less than 3/97 (weight ratio), the life of the catalyst and the reaction time The desired effect may not be obtained in terms of easiness of operation, and if it is more than 50/50 (weight ratio), the desired effect may not be obtained in terms of catalyst activity. There is. Therefore, the mixing ratio (B) / (A) is preferably in the range of 5/95 to 40/60 by weight.

In use, the catalyst of the present invention may be premixed at a predetermined mixing ratio, or the copper chloride-containing alumina particles (A) may be mixed in the reactor at a predetermined mixing ratio. The alumina particles (B) may be added separately. The catalyst of the present invention can be used under usual reaction conditions for producing EDC from ethylene. That is, the composition of the reaction raw material is usually such that the ratio of ethylene: oxygen: hydrochloric acid is in the range of about 1.0 to 1.8: about 0.55 to 0.9: 2 and the reaction temperature is 190 to 250. It is performed in the range of ° C.
As the oxygen source, high concentration oxygen or air can be used.

[0023]

EXAMPLES The present invention will be described in more detail with reference to the following examples. Reference Example 1-5 shows a method for producing copper chloride-containing alumina particles (A) and alumina particles (B).

[0024]

[Reference Example-1] 5.02 kg of cupric chloride (dihydrate)
Was dissolved in 37.0 kg of 35% hydrochloric acid, water was added to dilute the whole to 134 liters, and 15.92 kg of aluminum hydroxide was dissolved in 35.56 kg of 45% sodium hydroxide. Further, water was added and mixed with a solution diluted to 67.6 liters to form a gel coprecipitate. The gel coprecipitate was aged at room temperature for 48 hours, filtered, washed with water, and water was added to the obtained cake to form a slurry, which was then spray dried. The thus-spray-dried microspheres had an average particle size of 64 μm.

The microspheres were baked at 400 ° C. for 3 hours to obtain copper chloride-containing alumina particles (A). The properties of the obtained copper chloride-containing alumina particles (A) [sample (A)] are shown in Table 1.

[0026]

[Reference Example-2] The same preparation method as in Reference Example-1 was used.
Copper chloride-containing alumina particles (A) having different Cu contents as shown in 1 were prepared. The properties of the obtained copper chloride-containing alumina particles (A), samples (a), (c) and (d), are shown in Table-1.

[0027]

[Reference Example-3] Cupric chloride (dihydrate) 10 kg to 30 kg
22.7 kg of activated alumina fine particles obtained by firing aluminum hydroxide obtained by the Bayer method at 500 ° C. was added to the aqueous solution dissolved in water, and the mixture was thoroughly stirred for 1 hour and filtered to obtain particles. After drying at 110 ° C, firing was performed at 400 ° C for 3 hours. In this way, copper chloride-containing alumina particles (A) were obtained by the dipping method. The properties of the obtained copper chloride-containing alumina particles (A) [sample (e)] are shown in Table 2.

[0028]

[Reference Example-4] 5 wt% sodium aluminate 40 kg
40 kg of 2.5% by weight aluminum sulfate is mixed with
A gel-like precipitate was formed. The gel-like precipitate at room temperature
After aging for a time, it is filtered and washed with water, and water is added to the obtained cake to make a slurry. This and cupric chloride (dihydrate) 12
87 g was mixed with 4800 g of an aqueous cupric chloride solution dissolved in water, and spray-dried. The dry particles are heated to 400 ° C.
Then, the alumina particles (A) containing copper chloride were obtained by the post-deposition method. Obtained copper chloride-containing alumina particles (A)
The properties of [Sample (F)] are shown in Table 1.

[0029]

[Reference Example-5] An aqueous solution of aluminum sulfate was mixed with an aqueous solution of sodium aluminate to form a gel-like precipitate.
The gel precipitate was aged at room temperature for 5 hours, filtered, washed with water, and water was added to the obtained cake to form a slurry, which was spray-dried and then fired at 400 ° C. to obtain fine particulate activated alumina. 3000 g of the particulate activated alumina was impregnated with an aqueous solution containing 565 g of cupric chloride (dihydrate), followed by drying at 130 ° C. and firing at 400 ° C. for 3 hours to obtain copper chloride-containing alumina particles by an impregnation method. (A) was obtained. The properties of the obtained copper chloride-containing alumina particles (A) [sample (K)] are shown in Table 1.

[0030]

Reference Example-6 The operation of impregnating 3000 g of the particulate activated alumina obtained in Reference Example-5 with 1200 g of cupric chloride (dihydrate) and then drying was repeated twice. Copper chloride-containing alumina particles (A) were obtained in the same manner as in Reference Example-5. The properties of the obtained copper chloride-containing alumina particles (A) [sample (K)] are shown in Table 1.

[0031]

[Reference Example-7] 5% by weight of aluminum aluminate 10
0 kg of 100% of 2.5% by weight of aluminum sulfate was mixed to form a gel-like precipitate, which was aged at room temperature for 5 hours, washed with 500 kg of warm water at 60 ° C., and washed with water. To make a slurry, and add 20% nitric acid to 7.0 kg
In addition, aging was carried out at 50 ° C. for 3 hours. Then, it was spray dried and fired at 500 ° C. to obtain alumina particles (B). Table 1 shows the properties of the obtained alumina particles (B).

[0032]

[Table 1]

[0033]

[Table 2]

[0034]

[Table 3]

[0035]

[Example-1] Oxychlorination reaction activity (k) and fluidity were obtained by using the samples (A) to (K) of the copper chloride-containing alumina particles (A) prepared in Reference Examples-1 to 6 alone. The index (FI) was measured. The oxychlorination reaction activity (k) was measured by the following method. That is, copper chloride-containing alumina particles (A) [samples (a) to (h)] having a particle diameter of 44 to 150 μm 24.
5 g was inserted into a glass flow reactor having an inner diameter of 27 mm and a height of 500 mm. Then, a mixed gas of ethylene, anhydrous hydrochloric acid and oxygen (molar ratio 1: 1: 0.5) was preheated at a temperature of 150 ° C., and the space velocity against weight was 4600 (1-gas (NTP) /kg-cat.hr).
Then, it was introduced into the reactor through the diffuser plate of the # 2 glass filter to fluidize the copper chloride-containing alumina particles (A). The reaction temperature is raised by increasing the reaction temperature while fluidizing.
The reaction was carried out at 0 ° C., and the initial reaction activities (k) shown in Table 2 were obtained. (K) is v = k [C ₂ H ₄ ] [HCl]
^It was calculated from the formula of ^0.3 [O ₂ ] ^0.3 . Here, v represents the catalyst efficiency (gEDC / g.cat.sec).

[C ₂ H ₄ ]: Molar Fraction of Unreacted Ethylene [HCl]: Molar Fraction of Unreacted Anhydrous Hydrochloric Acid [O ₂ ]: Molar Fraction of Unreacted Oxygen Next, the fluidity index (FI) Observed.

The method for measuring the fluidity index (FI) is as follows. A mixed gas of ethylene, anhydrous hydrochloric acid and oxygen (molar ratio 1: 1: 0.5) was reacted as described above, and after the supply of oxygen and anhydrous hydrochloric acid among these gases was stopped, only ethylene gas was continuously added. Residual heat temperature 150
℃, weight hourly space velocity 3000 (1-gas (NTP) /kg-cat.h
The catalyst was fluidized in r). While maintaining the fluidized bed temperature at 210 ° C., the catalyst was reduced and the fluidized state was observed. The liquidity index (FI) is shown below. (FI) is shown in 7 stages of 0 to 6 shown below, in order to judge whether the flow state of the catalyst during the reaction or until reduction of ethylene only is good or bad, and the fluidity index of 6 is the best fluidity. Represents a catalyst. Flowability index Flow state of catalyst (FI) 0 C ₂ H ₄ , HCl, O ₂ (1: 1: 0.5 mol) Flow start (reaction start) Immediately after catalyst solidification.

1 C ₂ H ₄ , HCl, O ₂ (1: 1: 0.5 mole) Catalyst aggregation solidification within 3 hours after the start of distribution. 2 C ₂ H ₄ , HCl, O ₂ (1: 1: 0.5 mol) was reacted for 3 hours, then HCl and O ₂ were stopped, and only C ₂ H ₄ was passed through the gas to condense and solidify the catalyst within 3 minutes.

After reacting 3 C ₂ H ₄ , HCl, and O ₂ (1: 1: 0.5 mol) for 3 hours, HCl and O ₂ were stopped, and the catalyst was coagulated and solidified only with C ₂ H ₄ within 10 minutes of passing gas. .

After reacting with 4 C ₂ H ₄ , HCl and O ₂ (1: 1: 0.5 mol) for 3 hours, HCl and O ₂ were stopped, and only C ₂ H ₄ was passed through the catalyst to solidify the catalyst within 15 minutes. .

After reacting 5 C ₂ H ₄ , HCl, and O ₂ (1: 1: 0.5 mol) for 3 hours, HCl and O ₂ were stopped, and only C ₂ H ₄ was passed through the catalyst for 15 minutes or more to aggregate and solidify the catalyst. No.

6 After the above reaction for 3 hours, HCl and O ₂ were stopped, and only C ₂ H ₄ was passed, and the catalyst did not coagulate and solidify for 30 minutes or more. The initial reaction activity (k) of the copper chloride-containing alumina particles (A) alone was as shown in Table 2 and FIG.
_A positive correlation was observed between the product of ₂ O ₃ (weight ratio) and SA (m ² / g) and k.

[0043]

[Example-2] The copper chloride-containing alumina (A) [Sample (a)] prepared in Example-1 and the alumina particles (B) prepared in Reference Example-7 were (B) / (A). Weight ratio of 25/7
24.5 g of the catalyst physically mixed in 5 was charged into a glass flow reactor having an inner diameter of 27 mm and a height of 500 mm. The oxychlorination initial reaction activity (k) and fluidity index (FI) were measured in the same manner as in Example-1. Table 3 shows the relationship between the reaction activity and the fluidity index.
Furthermore, a catalyst obtained when only the (B) / (A) is physically mixed at a weight ratio of 25/75 and the activity of the above catalyst is changed with time, and only copper chloride-containing alumina particles (A) [sample (A)] are used. The time course of activity was examined. Changes in oxychlorination reaction activity (k) are shown in Table 3 and FIG. Table-
3 and FIG. 2 show that the initial reaction activity (k) is slightly lower in the catalyst containing 25% of alumina particles (B) than in the catalyst consisting of only copper chloride-containing alumina particles (A), but the fluidity is The catalyst has the best fluidity with a sex index of 6. Further, from FIG. 2, the catalyst composed of a mixture of the copper chloride-containing alumina particles (A) and the alumina particles (B) has a reaction activity (k) after 500 hours of only the copper chloride-containing alumina particles (A). It turns out to be superior to the catalyst. The excellent effect of the catalyst containing 25% of alumina particles (B) is that the fluidity index is improved to improve the contact efficiency between the catalyst and the raw material gas, prevention of catalyst adhesion and aggregation, and copper chloride-containing alumina particles (A). It is considered that this is achieved by the prevention of volatilization of the active ingredient and the like by the copper particles and the chlorine which are volatilized from the above being captured by the alumina particles (B).

As described above, the catalyst of the present invention can be said to be a highly active and long-life catalyst having good fluidity and capable of withstanding long-term use.

[0045]

[Table 4]

[0046]

[Comparative Example-1] The case where only the copper chloride-containing alumina particles (A) [Sample (f)] obtained in Reference Example-4 was used, and the sample (f) and the alumina particles (B) of Reference Example-7 (B) were used. ) (B) /
The catalyst physically mixed at a mixing ratio of (A) of 25/75 (weight ratio) was evaluated in the same manner as in Example-2.

Table 3 and FIG. 2 show the results of reaction activity (k) fluidity index (FI) and time-dependent changes in activity. The catalyst obtained by physically mixing the copper chloride-containing alumina particles (A) sample (f) and the alumina particles (B) has a fluidity
The catalyst life is improved, but in the sample (f), Cu / A
Since the product of l ₂ O ₃ (weight ratio) and specific surface area (m ² / g) is as small as 18, the reaction activity is low.

[0048]

Example 3 Alumina particles (B) prepared in Reference Example 6 were physically added to the copper chloride-containing alumina particles (A) [Sample (D)] prepared in Reference Example 2 in an amount of 25% by weight. Using 3.5 kg of the catalyst obtained by mixing with, the inner diameter of the reaction tube is 100 m
The reaction was carried out in a fluidized bed reactor having a height of 3,000 mm and a height of 3,000 mm, equipped with a jacket capable of circulating a heat medium, and equipped with a gas dispersion plate on the bottom of which three metal meshes of 250 mesh were stacked.

A mixed gas of ethylene, anhydrous hydrochloric acid and oxygen (molar ratio 1.7: 2.0: 0.7) was preheated to 150 ° C., and the weight hourly space velocity per catalyst was 1900 (1-gas (NTP) / kg- cat.hr)
Was introduced to conduct an oxychlorination reaction of ethylene. The reaction results are shown in Table-4.

[0050]

Comparative Example-2 In place of the copper chloride-containing alumina particles (A) [Sample (D)] in Example-3, the copper chloride-containing alumina particles (A) obtained in Reference Example 6 [Sample (K)]. ] The oxychlorination reaction of ethylene was performed in the same manner as in Example 3 except that The reaction results are shown in Table-4.

As is clear from Table 4, the catalyst of the present invention had little pressure fluctuation and the temperature distribution inside the reaction tube was stable, so that the operation during the reaction could be smoothly carried out. Further, the catalytic activity is high and the EDC yield is high.

[0052]

[Table 5]

[Brief description of the drawings]

FIG. 1 is a diagram showing a relationship between a product of Cu / Al ₂ O ₃ (weight ratio) and a specific surface area and an initial reaction activity (k).

FIG. 2 shows reaction time (hr) and catalyst activity (k ×).
It is a figure which shows the relationship with 10 ^<-3> .

Front page continued (72) Inventor Yoshito Yamashita 6-3-2-241 Higashi Hagoromo, Takaishi, Osaka

Claims (3)

[Claims] 1. A Cu content in the range of 8 to 15 wt.
The weight ratio of u / Al ₂ O ₃ is in the range of 0.10 to 0.22, and Cu / Al ₂ O ₃ (weight ratio) and specific surface area (m ² /
g) for ethylene oxychlorination, which is a physical mixture of copper chloride-containing alumina particles (A) having a product of 30 m ² / g or more and alumina particles (B) having a specific surface area of 160 m ² / g or more Fluid catalyst. 2. A fluidized catalyst for ethylene oxychlorination according to claim 1, wherein the alumina of the copper chloride-containing alumina particles (A) is amorphous alumina. 3. A mixing ratio (B) / of the physical mixture.
The fluid catalyst for ethylene oxychlorination according to claim 1 or 2, wherein (A) has a weight ratio in the range of 3/97 to 50/50.