JP2002284723A - Catalytic reaction method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a catalytic reaction method which comprises through carrying out processes ranged from the production of a catalyst to a chemical reaction using the catalyst, enables the omission of a work for charging the catalyst into a reactor, and permits the chemical reaction in stable conditions for a long period. SOLUTION: The catalytic reaction method comprises supplying an active component solution into a catalyst carrier-charged flow-through reactor to impregnate and fix the active component to the catalyst carrier, thereby producing the catalyst carried on the carrier in the flow-through reactor, and then supplying reaction raw materials into the flow-through reactor to react the reaction raw materials with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a target product using a catalyst. More specifically, the present invention relates to a method for consistently performing a process from production of a catalyst to production of a target product using the catalyst.

[0002]

2. Description of the Related Art Catalytic reactions for producing a target product using a catalyst are carried out in various reaction systems. One of the main ones is a solid catalyst in which an active ingredient is supported on a carrier. There is a method of supplying a reaction raw material to a flow-type reactor to cause a reaction. For example, the production of styrene from ethylbenzene, the production of ethylene oxide from ethylene, and the production of acrylic acid from propylene, which are carried out on a large scale at petrochemical plants, are exclusively carried out by this reaction method. In this reaction system, the reactor must be filled with a solid catalyst prior to the start of the reaction, and the catalyst deteriorates with time during the reaction, so it must be periodically replaced with a new catalyst.

[0003]

However, great care must be taken to fill the reactor with the catalyst so that no impurities are mixed therein. In particular, in the case of a catalyst that deteriorates when it comes into contact with oxygen or moisture, the reactor must be filled under an inert gas atmosphere or a dry gas atmosphere, and the operation is troublesome.

An object of the present invention is to provide a catalyst reaction method in which a catalyst is produced in a reactor for performing a catalytic reaction, thereby eliminating the operation of charging the catalyst into the reactor.

[0005]

In the present invention, a catalyst carrier is filled in a flow reactor, and a solution of the active component is supplied to the catalyst carrier to impregnate the catalyst carrier with the active component. When the impregnation is completed, the remaining solution is discharged, and then the drying, calcination, reduction, etc., are performed, as appropriate, to fix the impregnated active ingredient to the carrier, and the active ingredient is supported on the carrier in situ. Is generated. As a result, the same state as when the flow-type reactor is filled with the pre-produced catalyst with a carrier is formed, and a desired catalytic reaction can be performed by supplying a reaction raw material to the flow reactor in a conventional manner. .

As a catalyst carrier for supporting an active ingredient,
Some of the active components may be previously supported in addition to the usual catalyst carrier. For example, by replenishing the deteriorated catalyst which has reduced the amount of the active component carried by use with the active component according to the method of the present invention, the catalyst can be reused.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a catalyst carrier and an active component to be carried on the catalyst carrier may be appropriately selected according to a target catalytic reaction.

The active ingredient may be in any form as long as it can be dissolved in a solvent to form a solution. In general, it is preferable to use a water-soluble one.

The concentration of the active component in the solution when impregnating the catalyst carrier with the active component may be appropriately determined according to the concentration of the active component in the catalyst to be finally obtained. If the concentration of the active ingredient in the solution is too high, the active ingredient may be thickly attached to the outer surface of the support, causing the particles of the finally obtained catalyst with a support to adhere to each other or closing the gap between the particles. Be careful as there are.

[0010] The impregnation of the active ingredient into the catalyst carrier may be carried out by filling the catalyst carrier into a flow-type reactor, supplying a solution containing the active ingredient thereto, and bringing the catalyst carrier into contact with the solution. At this time, it is preferable to circulate the solution through the packed bed of the catalyst carrier in order to uniformly impregnate the active ingredient into the catalyst carrier.
The impregnation requires a sufficient time, and the impregnation is usually performed for 5 minutes or more, preferably 10 minutes or more.

After completion of the impregnation, the remaining solution is discharged from the flow reactor, and the impregnated active component is then fixed on a carrier to produce a desired catalyst. For example, in the simplest case, after the remaining solution is discharged from the flow-type reactor, heated and circulated air is passed through the solution to perform drying and firing operations. If the reduced catalyst is desired, the reduction treatment may be performed by circulating a reducing agent following the drying and firing operations. Further, in the case of impregnating with a solution of a compound that produces an insoluble metal salt, the impregnated metal salt may be converted to a hydroxide by treating with an aqueous alkali solution prior to drying and firing. . In addition, when the amount of the active ingredient carried does not reach the desired amount in one impregnation due to the dilute solution used for impregnation, the operations of impregnation, drying and baking may be repeated. By the above operation, the same state as when the catalyst with a carrier prepared in advance is filled in the flow-type reactor is formed, and thereafter, the catalytic reaction may be carried out by supplying the reaction raw materials by a conventional method.

[0012] The present invention provides a catalyst-supported catalyst comprising a fixed bed, a moving bed,
Any reaction used in the form of a fluidized bed or the like can be targeted. For example, an oxidation reaction, a dehydrogenation reaction, a hydrogenation reaction and the like can be targeted.

One of the preferable objects of the present invention is a reaction using a catalyst in which phosphoric acid is supported on alumina, for example, hydrocarbons having a partial structure in which hydrogen atoms are bonded to carbon atoms adjacent to the catalyst. Is a so-called oxidative dehydrogenation reaction in which a mixed gas of oxygen and oxygen is brought into contact to convert the partial structure into an ethylenically unsaturated bond.

In this case, an aqueous solution of orthophosphoric acid, metaphosphoric acid, pyrophosphoric acid or a salt thereof is used as a solution of the phosphorus compound to be impregnated into alumina, and the content of the phosphorus compound in the catalyst is converted into phosphorus atoms. Impregnation so as to be 0.01 to 2.0% by weight. When the impregnation is completed and the remaining solution is discharged from the flow reactor, a relatively low-temperature gas of room temperature to about 300 ° C. is introduced and dried, and then a high-temperature gas of about 300 to 1300 ° C. is removed. What is necessary is just to introduce and bake.

[0015]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples unless it exceeds the gist. Slowly added aluminum nitrate _{Al (NO 3) 3 · 9H} 2 O in aqueous solution at a temperature of 30 ° C. or less with stirring aqueous ammonia 3N,; [Example] phosphorus / alumina catalyst prepared in the reaction tube
A precipitate of hydroxide was formed. When the formation of the precipitate was completed, the addition of aqueous ammonia was stopped, and the precipitate of aluminum hydroxide was collected by filtration and washed with water. The obtained aluminum hydroxide was placed in a dryer and dried at 120 ° C. overnight, and then placed in a muffle furnace and calcined at 700 ° C. for 5 hours. A small amount of water was added to this calcined product, wet crushed with a kneader for 2 hours, and then an average particle size of 2.5φX2.
5 mm pellets were obtained. After drying the pellets at 120 ° C. overnight with a dryer, the pellets are placed in a muffle furnace and placed at 100 ° C. /
At that time, the temperature was raised to 1200 ° C. and calcined at this temperature for 3 hours to obtain an alumina carrier.

The obtained alumina carrier (2 ml) has an inner diameter of about 8 m.
m, and a quartz chip was filled at the inlet of the reaction tube. The reaction tube was set upright in an electric furnace, and a Teflon (registered trademark) tube having an outer diameter of 3 mm was attached to each of the upper and lower parts, and a liquid circulation system comprising an upper Teflon tube-solution tank-liquid pump-lower Teflon tube-reaction tube was set. A road was formed. About 2.4% by weight of an aqueous solution of ammonium dihydrogen phosphate at room temperature was placed in the solution tank, and the pump was operated to circulate in the circulation path. After 2 minutes from the circulation, the pump was stopped, and the mixture was allowed to stand still for 13 minutes. Then, the impregnating liquid in the reaction tube was discharged from the lower portion of the reaction tube.

Next, the upper and lower Teflon tubes of the reaction tube were removed from the circulation path, and room temperature air was fed through the lower Teflon tube at 26 ml / min for 1.5 hours.
The temperature was kept at 0 ° C. for 2 hours.

The Teflon tube at the lower part of the reaction tube was removed, and the catalyst layer temperature was kept at 500 ° C. for 2.5 hours while air was fed from the Teflon tube at the upper part of the reaction tube at a rate of 26 ml / min. A reaction tube filled with the catalyst was formed. Oxidative dehydrogenation of p-chloroethylbenzene; while feeding air at 26 ml / min from the top of the reaction tube, the catalyst layer was heated to 540 ° C.
Temperature. Next, the air was switched to a mixed gas consisting of p-chloroethylbenzene, water, and air to perform oxidative dehydrogenation of p-chloroethylbenzene.

The composition of the mixed gas is p-chloroethylbenzene / oxygen / water = 1.0 / 0.52 / 3.0 (molar ratio).
And the liquid hourly space velocity of p-chloroethylbenzene (LHS
V) was 1.92 / h. One hour after the start of the reaction, the reaction tube outlet gas was liquefied and collected, and this was analyzed by gas chromatography. Table 1 shows the reaction results and the phosphorus content of the catalyst. REFERENCE EXAMPLE 120 g of the alumina carrier obtained in Example was placed in a basket of wire mesh, immersed in about 600 g of an aqueous solution of about 2.4% by weight of ammonium dihydrogen phosphate for 15 minutes, and air-dried together with the basket for 5 hours. C., dried overnight at 500.degree. C. in a quartz firing tube under a stream of air at 500.degree. C. for 2.5 hours to obtain a catalyst in which phosphorus was supported on alumina. 2 ml of the obtained catalyst was filled in a quartz reaction tube in the same manner as in [Example]. An oxidative dehydrogenation reaction of p-chloroethylbenzene was performed in exactly the same manner as in the example. The results are shown in [Table 1].

[0020]

[Table 1]

In the table, p-ClEB represents p-chloroethylbenzene, and p-ClSt represents p-chlorostyrene.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) C07C 25/28 C07C 25/28 // C07B 61/00 300 C07B 61/00 300 F term (reference) 4G069 AA03 AA08 AA10 BA01A BA01B BB14A BB14B CB07 DA06 FA01 FA02 FB18 FB77 FC08 GA09 4H006 AA02 AB46 AC12 BA53 BA55 BA81 BA82 BC13 BC30 BD80 BE30 EA21 4H039 CA20 CC10

Claims (5)

[Claims] 1. An active ingredient solution is supplied to a flow-type reactor filled with a catalyst carrier which may partially support the active ingredient, whereby the catalyst carrier is impregnated with the active ingredient and the remaining solution is discharged. After that, a catalyst with a carrier is generated in a flow reactor by performing an operation of fixing the impregnated active component to the carrier, and then the reaction raw material is supplied to the flow reactor filled with the catalyst with the carrier. A catalytic reaction method characterized by causing a reaction. 2. The catalytic reaction method according to claim 1, wherein the catalyst carrier on which a part of the active component may be supported is a catalyst in which a part of the active component has been used in the reaction. 3. A method in which a phosphorus compound solution is supplied to a flow-type reactor filled with an alumina carrier to impregnate the alumina carrier with the phosphorus compound, and the remaining solution is discharged. And baking to form a flow-type reactor filled with a catalyst in which a phosphorus compound is supported on an alumina carrier, and then supplying a reaction raw material thereto to cause a reaction. 4. The method according to claim 3, wherein the catalyst contains 0.01 to 2.0% by weight of a phosphorus compound in terms of phosphorus atoms. 5. A reaction raw material is a gas containing oxygen and a hydrocarbon having a partial structure in which a hydrogen atom is bonded to two adjacent carbon atoms, and the reaction is performed by forming an ethylenically unsaturated bond on the hydrocarbon. The method according to claim 3 or 4, wherein the reaction is a dehydrogenation reaction to be formed.