JP2008224257A - Catalytic activity evaluation device and evaluation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a catalytic activity evaluation device and evaluation method, capable of evaluating easily a plurality of catalyst samples simultaneously under the same condition. <P>SOLUTION: This catalytic activity evaluation device is provided with a control means for controlling a flow rate of raw material gas introduced into a reactor, the reactor built in with a storage part for storing the plurality of catalysts, and a gas detecting means for detecting a catalytic reaction product, the reactor comprises a reactor main body having a raw material gas buffer part and a plurality of catalyst installation parts in its inside, and a heating part for heating uniformly a temperature of the catalyst, and has a single raw material gas introduction part and a plurality of reaction gas drawing-out parts, the raw material gas is introduced into the respective catalyst installation parts via the buffer part, to be drawn out from the reactor after catalytic reaction in each catalyst installation part, respective catalytic reaction product gases drawn out from the different drawing-out parts are respectively communicated with the gas detecting means via a catalytic reaction product gas control means, in the catalyst activity evaluation device. The present invention discloses also the catalyst activity evaluation method using the same. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a catalyst activity evaluation apparatus and an evaluation method capable of quickly and easily evaluating reaction activities of a plurality of catalysts under the same conditions.

  Catalysts are used in various chemical reactions. However, finding the optimal catalyst is not easy. Conventional catalyst search relies heavily on trial and error, and the items that can be evaluated in a single activity test are limited, and thus a great deal of time and labor has been required. Further, it was not possible to evaluate a plurality of catalysts under completely the same conditions.

  For this reason, a catalytic activity evaluation apparatus (equivalent to the simultaneous evaluation of the reaction activity of multiple catalysts under the same conditions (temperature, pressure, gas flow rate) used in the actual process and efficient measurement of the catalytic activity ( Patent Document 1), a method for quickly and easily developing a catalyst suitable for a specific gas phase reaction at low cost (Patent Document 2), and a gas output value pattern of a known type and concentration using a plurality of gas sensors A method of identifying the type of product gas by matching and calculating the concentration (Patent Document 3) has been proposed.

In Patent Document 1, a switching unit is provided in the reaction product gas deriving line, and among the reaction product gases derived from each catalyst sample, only one line is sequentially conducted to the product detection unit and detected by GC. To do. In Patent Document 2, a ceramic boat containing a quartz cup filled with a catalyst is placed in a quartz reaction tube, heated in a tubular electric furnace, and the amount of precipitated carbon produced on the catalyst is measured, whereby the catalytic activity is measured. Is evaluated. In Patent Document 3, a plurality of catalysts are arranged in a matrix on a plate material, heated by a hot plate, and the catalytic reaction product gas is forcibly sucked by a suction device, and the electrical conductivity of the semiconductor changes. The concentration is measured with a semiconductor gas sensor. However, neither method is easy to say.
JP 2002-5918 A JP 2003-164767 A JP 2000-193622 A

  It is an object of the present invention to provide a catalyst activity evaluation apparatus and an evaluation method capable of easily evaluating a plurality of samples simultaneously and under the same conditions for the purpose of improving the efficiency of catalyst search. .

  In order to solve the above-mentioned problems, the present inventors have intensively studied, and as a result, found that the object can be achieved by the following constitution, and have reached the present invention.

That is, the present invention is as follows.
(1) A catalyst comprising source gas control means for controlling the flow rate of the source gas introduced into the reaction vessel, a reaction vessel containing a housing for accommodating a plurality of catalysts, and a gas detection means for detecting catalytic reaction products An activity evaluation device,
The reaction vessel comprises a vessel main body having a source gas buffer unit and a plurality of catalyst installation units therein, and a heating unit for uniformly heating the temperature of the catalyst, and a single source gas introduction unit and a plurality of catalyst reaction generations A gas outlet,
The raw material gas is introduced into each catalyst installation section through the buffer section, and after being subjected to a catalytic reaction in each catalyst installation section, is led out from the reaction vessel,
A catalytic activity evaluation apparatus characterized in that catalyst reaction product gases derived from different deriving units are respectively conducted to gas detection means via catalyst reaction product gas control means.
(2) The catalyst activity evaluation apparatus according to (1), further including switching means for connecting the catalyst pretreatment gas to the raw material gas introduction line and the catalytic reaction product gas lead-out line.
(3) The catalyst activity evaluation apparatus according to (1) or (2), wherein the gas detection means is a gas detection tube.
(4) A plurality of storage units installed under the same conditions are filled with a plurality of catalysts of the same type or different from each other, a raw material gas is introduced into the storage units, and the raw material gas and the plurality of catalysts are heated. The reaction is carried out by contacting the bottom, and the concentration of the product gas contained in the catalytic reaction product gas derived from different outlets is measured using a plurality of gas detector tubes installed downstream. The catalyst activity evaluation method which carries out relative evaluation on the same conditions as a plurality of catalysts.
(5) After introducing a catalyst pretreatment gas into the housing portion and pretreating the plurality of catalysts, a raw material gas is introduced into the housing portion and the raw material gas and the plurality of catalysts are heated under heating conditions. The catalyst activity evaluation method which carries out relative evaluation on the same conditions of the some catalyst as described in said (4) which is made to contact.
(6) A catalytic activity evaluation method for relatively evaluating a plurality of catalysts according to (4) or (5) above under the same conditions, wherein the gas detection tube is a general-purpose gas detection tube.

  According to the present invention, conditions such as gas flow rate, reaction pressure, and reaction temperature are uniform for a plurality of catalysts at a time, so that the catalyst activity can be accurately, quickly, and easily evaluated under the same conditions. The catalyst can be evaluated in a very small amount, and even when many catalysts are made and evaluated, the amount of the prototype of the catalyst is small.

  Moreover, since the generation amount of the reaction product can be evaluated using a commercially available gas detector tube, the evaluation can be performed inexpensively and easily. Since it was confirmed that the evaluation result in this gas detector tube shows almost the same tendency as the component analysis result by gas chromatography, according to the present invention, the relative comparative evaluation of the catalyst by the gas reaction becomes possible. . Therefore, the catalyst search becomes easy.

  Hereinafter, an embodiment of a catalyst activity evaluation apparatus of the present invention will be described in detail with reference to the drawings. FIG. 1 is a system diagram showing an embodiment of a catalyst activity evaluation apparatus according to the present invention. The catalytic activity evaluation apparatus includes a raw material gas control means 1 for controlling a flow rate of a raw material gas introduced into a reaction vessel, a reaction vessel 3 in which a plurality of (three in FIG. 1) catalysts are accommodated, a catalytic reaction product. Is provided with a gas detection means 4 and a purge gas control means 2. The reaction vessel 3 includes a container main body having a plurality of (three in FIG. 1) catalyst installation portions 31 and a heating portion 32 for uniformly heating the temperature of the catalyst, and a single source gas introduction portion 33. And a plurality of catalyst reaction product gas deriving units 34 equal to the number of catalyst installation units, and the raw material gas is led out from the catalyst installation unit after undergoing a catalytic reaction in each catalyst installation unit. The catalytic reaction product gases derived from a plurality of different deriving units 34 are respectively conducted to the gas detection means 4 via the catalytic reaction product gas control means 5 that controls the flow rate thereof to be constant.

  In the catalytic activity evaluation apparatus of the present invention shown in FIG. 1, a buffer gas for catalyst pretreatment (such as a mixed gas of hydrogen and nitrogen for hydrogen reduction) 14 is provided in the introduction line of the raw material gas and the outlet line of the catalytic reaction product gas. Switching means (three-way valves) 6, 7 and 8 for conducting are provided. Having such a switching means is a preferred embodiment, but it may not be provided. By having the switching means, it is possible to pretreat the catalyst filled in the catalyst installation section.For example, when evaluating a catalyst that is very easily oxidized, a reduction treatment is performed in advance using a pretreatment gas. After that, it becomes possible to introduce a raw material gas for evaluation. Thereby, the accuracy of evaluation can be improved.

  Further, after the catalyst is adjusted, the inside of the reaction vessel can be purged using an inert gas (for example, nitrogen gas) via the purge gas control means 2, so that the evaluation accuracy can be further improved.

  Since the material gas control means (pressure regulating valve) 1 is provided in the upstream of the reaction vessel 3, the flow rate of the material gas can be controlled. Thereby, since the concentration of the raw material gas introduced into the catalyst installation portion can be adjusted, it is possible to prevent poor evaluation caused by the shortage of the raw material gas. The flow rate control of the raw material gas is performed by the pressure regulating valve 1, and a three-way valve 6 for switching the hydrogen reduction gas and a flow meter 9 are installed on the way.

  It is preferable that the flow rate of the raw material gas flowing through the catalyst installation part is 0.1 to 0.3 L / min and the space velocity is 2 to 6 cm / sec.

  The reaction vessel 3 has a sealed structure in order to prevent the product gas from leaking to the outside and air from entering to reduce the analysis accuracy. A single source gas introduction part 33 is installed on the upper wall of the reaction vessel 3, from which the source gas is introduced into the reaction vessel. The introduced source gas is introduced into the catalyst installation unit 31 via the source gas buffer unit 35 provided in the upper part of the catalyst installation unit. The catalyst installation unit 31 is arranged uniformly in the reaction vessel 3 so that the raw material gases are uniformly in contact with the plurality of catalysts, and the buffer unit 35 is provided. It will be installed below. This makes it possible to evaluate a plurality of different catalysts under the same conditions.

  As the reaction vessel 3, for example, a pressure resistant cylindrical stainless steel vessel can be used. The catalyst installation part 31 is designed in an elongated shape so that even a small amount of catalyst can be evaluated. A small amount (about 0.5 g) of the evaluation catalyst is filled therein to form a catalyst installation layer. A heating unit 32 that uniformly heats the temperature of the catalyst is provided around the reaction vessel 3. The heating unit 32 is covered with, for example, a mantle heater and the heating temperature is controlled using a temperature controller in order to control the heating temperature constant. Control. The raw material gas is led out from the reaction vessel after undergoing a catalytic reaction at the catalyst installation portion.

  Since the plurality of catalyst reaction product gas deriving units 34 are provided on the lower walls of the plurality of catalyst installation units 31, the catalyst reaction product gas is derived from these deriving units, and the derived gases have different lines. Is conducted to the gas detection means 4 via the.

  The heating temperature of the reaction vessel 3 varies depending on the type of catalyst used, but can be appropriately set within the range of 150 to 350 ° C. The pressure in the reaction vessel can be appropriately set in the range of 0.05 to 0.4 MPa.

  A catalytic reaction product gas control means (flow rate adjusting valve) 5 is provided in the downstream of the reaction vessel 3 in order to adjust the flow rate of the gas derived from the reaction vessel. Using the flow meter 10, the space velocity of the gas introduced into the gas detection means 4 is made as uniform as possible. Thereby, the measurement error in a gas detection means can be decreased. In this case, the gas flow rate is preferably 0.1 to 0.3 L / min, and the space velocity is preferably 2 to 6 cm / sec, similarly to the flow rate of the gas flowing through the catalyst installation portion.

  Finally, the gas detection means 4 measures the concentration of the product gas contained in the product gas derived for each catalyst. The gas that has passed through the gas detection means is exhausted. If a commercially available general-purpose gas detection tube is used as the gas detection means 4, it becomes possible to perform measurement inexpensively and easily. Examples of commercially available gas detector tubes include alcohol gas detector tubes such as methanol and ethanol, ether gas detector tubes such as dimethyl ether, hydrocarbon gas detector tubes such as methane and ethane, carbon monoxide gas detector tubes, and the like. However, it is not limited to these.

  Since the hydrogen reduction buffer gas 14 described above is used for pretreatment of the evaluation catalyst, it is preferable to use a mixed gas accommodated in a Tedlar pack or the like, but it may be appropriately introduced from a gas cylinder. The gas is circulated by the circulation pump 15. During catalyst pretreatment, the three-way valves 6, 7, and 8 for switching the hydrogen reducing gas and the purge gate valve 16 are operated to circulate the hydrogen reducing gas only through the evaluation catalyst, and this occurs during catalyst adjustment in the middle. A water trap 13 is provided.

  Each member in the apparatus such as the raw material gas storage container, the reaction container 3 and the gas detection means 5 is connected using a resin tube such as stainless steel, glass or Teflon (registered trademark).

  In the present invention, usable raw material gases are not particularly limited, and examples thereof include gases such as carbon monoxide, carbon dioxide, hydrogen, and methanol, mixed gases thereof, and various synthesis gases. The kind of source gas is determined according to the catalyst to be evaluated. In addition, in FIG. 1, the example using the mixed gas which mixed the carbon dioxide and hydrogen is shown.

  Further, the catalyst filled in the catalyst installation portion may have various shapes such as a spherical shape, a cylindrical shape, a pellet shape, a honeycomb shape, and a plate shape.

  Since the catalyst activity evaluation apparatus according to the present invention uses the above-described catalyst activity evaluation apparatus, it can be a method for relatively evaluating a plurality of catalysts under the same conditions. In other words, after a plurality of storage units installed under the same conditions are filled with a plurality of catalysts of the same type or different from each other to form a catalyst installation layer, a raw material gas is introduced into the storage unit to cause a catalytic reaction. The product gas concentration in the catalytic reaction product gas derived from the different derivation units may be measured by using a plurality of gas detector tubes installed in the downstream. Therefore, since only one pass of the raw material gas is required in the heating reaction vessel, the activities of a plurality of catalysts can be evaluated quickly and easily.

  EXAMPLES Next, although an Example demonstrates this invention in detail, referring drawings, this invention is not limited only to a following example.

[Evaluation equipment]
The test was performed using a fixed bed flow type catalyst activity evaluation apparatus. A system diagram is shown in FIG. The reaction uses a cylindrical stainless steel (SUS) reaction vessel 3 having an outer diameter of 75 mmΦ and a height of 120 mm. As shown in FIG. 2, a raw material gas buffer unit 35 having a height of 50 mm is provided in the reaction vessel 3. Three stainless steel clads were shaved, and ^three catalyst installation portions 31 having an inner diameter of 10 mmΦ, a height of about 50 mm, and an internal volume of about 4 cm 3 were arranged uniformly. One to several pieces (about 0.5 g) of 5 mmΦ × 6 mm pellet type catalyst were filled in the catalyst installation part 31. The periphery of the reaction vessel was covered with a mantle heater 32, and the heating temperature was controlled using a temperature controller.

  As shown in FIG. 3, the reaction vessel 3 is of a sealed type and has a temperature measurement seat on the bottom surface.

  The cylinder containing the raw material gas or the purge gas, the reaction vessel 3 and the gas detection tube 4 were connected using a stainless steel (SUS) tube having an inner diameter of 6 mm. It is also possible to connect using a Teflon (registered trademark) or glass tube.

  The flow rate control of the source gas and the purge gas was performed by the pressure regulating valve 1, and a purge gas gate valve 2 and a hydrogen reduction gas switching three-way valve 3 were installed on the way. The flow rate adjusting valve 5 and the flow meter 10 for the gas led out from the reaction vessel are provided in the downstream of the reaction vessel, and the space velocity of the raw material gas in the catalyst installation portion is unified during the evaluation. The methanol concentration contained in the product gas derived for each catalyst was measured with a commercially available gas detector tube 4. The gas that passed through the detector tube was exhausted.

  The hydrogen reduction gas was stored in the storage pack 14 so that it could be used for pretreatment of the evaluation catalyst, and the gas was circulated by the circulation pump 15. During catalyst pretreatment, the three-way valves 6, 7, 8 for switching the hydrogen reducing gas and the purge gate valve 16 are operated to circulate the hydrogen reducing gas only to the evaluation catalyst, and this occurs during catalyst adjustment in the middle. A water trap 13 was provided.

[Evaluation methods]
(1) Preparation of catalyst activity test The reaction container was removed from the apparatus, the weight of the catalyst used was measured and set in the reaction container, and the reaction container was set in the apparatus. The upper and lower sides of the methanol gas detector tube were folded using a dedicated tool, and the detector tube was installed at a predetermined position.

(2) Production of Hydrogen Reduction Gas Hydrogen reduction gas (H ₂ + N ₂ ) was sealed in a 10 L tedlar pack 14 and set in an apparatus. The three-way valves (hydrogen reduction switching) 6 and 7 were switched to the hydrogen reduction line, and the gas circulation pump 15 was turned on. The flow meter 10 was adjusted to a predetermined flow rate by the flow rate adjustment valve 5 of each line. The temperature controller was set to the hydrogen reduction temperature and heating was started. After reaching the set reduction temperature, it was held for a predetermined time.

(3) Gas replacement The temperature control device switch was turned off. When the temperature dropped to some extent, the three-way valve (purge switching) 8 was switched to the gas exhaust line, the purge gate valve 16 was opened (H ₂ + N ₂ ), and the mixed gas was exhausted. When exhausting the entire amount, the gas circulation pump 15 was stopped. The three-way valve (hydrogen reduction switching) 6 was switched to the activity test line. The purge gas gate valve 2 was opened, gas was introduced into the reaction system from a nitrogen cylinder, and the reaction system was purged with nitrogen for about 10 minutes.

(4) Catalyst activity test The purge gas gate valve 2 was closed, and the main stopper of the nitrogen cylinder was closed. The cylinder of the CO ₂ + H ₂ mixed gas was opened and the raw material gas was introduced. The pressure adjusting valve 1 was adjusted to the reaction pressure condition. The temperature controller was set to the activity test temperature and heating was started. The raw material gas was collected from the sampling port (before the reaction) 11 with a microsyringe, and the gas composition before the reaction was confirmed by gas chromatography. When 120 minutes passed after reaching the set temperature, the three-way valve (hydrogen reduction switching) 7 was switched to the reaction tube side, and the purge gate valve 16 was closed. The reaction gas was allowed to flow through the reaction tube. When a predetermined time (about 5 minutes) had elapsed, the purge gate valve 16 was opened, the three-way valve (hydrogen reduction switching) 7 was switched to the hydrogen reduction line, and the reaction was completed. The reaction tube was removed, and the color of the reaction tube due to the product was confirmed.

The switch of the temperature control device was turned off. The main stopper of the CO ₂ + H ₂ mixed gas cylinder was closed. The main stopper of the nitrogen cylinder was opened, and the inside of the reaction system was purged with nitrogen. When the temperature dropped, the main stopper of the nitrogen cylinder and the purge gate valve 16 were closed.

FIG. 4 and FIG. 5 show the measurement results of the temperature in each reaction line and the measurement results of the CO ₂ gas concentration (vol%). From these results, it was found that the error was 1% or less.

(5) Experimental results Each of the three types of catalysts was tested twice to confirm the reproducibility and accuracy of the amount of methanol produced by the gas detector tube. The detection status of the gas detector tube is shown in FIG. 6 (the arrow in the figure indicates the boundary where the color of the gas detector tube is changed to pink), and the test results are shown in Table 1. From these results, the repeatability of the amount of methanol produced by the gas reaction tube was generally good. Moreover, it turned out that methanol conversion shows the same tendency as a gas chromatography analysis value (refer FIG. 7).

  FIG. 8 is a diagram showing the results of evaluating a plurality of catalysts by changing the reaction temperature in the catalyst activity evaluation apparatus of the present invention. From this result, it can be seen that catalyst A and catalyst C have high activity, catalyst B has moderate activity, and catalyst D and catalyst E have low activity.

  On the other hand, FIG. 9 is a diagram showing the results of evaluating a plurality of catalysts at different reaction temperatures in a microwave reactor. From this result, it can be seen that catalyst A and catalyst C have high activity, catalyst B has moderate activity, and catalyst D and catalyst E have low activity.

  From the results of FIG. 8 and FIG. 9, it was found that the relative tendency of the catalyst activity is similar, and the evaluation by the catalyst activity evaluation apparatus of the present invention is effective for searching for the catalyst used in the actual reaction.

  Since the catalyst activity evaluation apparatus and the catalyst activity evaluation method of the present invention can evaluate the activity of the catalyst in a relatively short time with a very simple operation, they are effective in searching for various gas reaction catalysts.

It is a systematic diagram of the catalyst activity evaluation apparatus used in the Example of this invention. It is a figure explaining the outline of a catalyst installation part. It is a figure explaining the outline of a reaction container. It is a figure which shows the temperature measurement result in each reaction line of the catalyst activity evaluation apparatus of this invention. It is a figure which shows the gas composition measurement result in each reaction line of the catalyst activity evaluation apparatus of this invention. It is a photograph which shows the methanol production amount of a gas detection tube. It is a figure which shows the methanol conversion rate analysis result by GC. It is a figure which shows the catalyst activity evaluation result in the catalyst activity evaluation apparatus of this invention. It is a figure which shows the test result in a microwave reactor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pressure control valve 2 Purge gas gate valve 3 Reaction container 31 Catalyst installation part 32 Heater 33 Raw material gas introduction part 34 Reaction gas outlet part 35 Buffer part 4 Gas detection pipe 5 Flow rate adjustment valve 6 Three-way valve (hydrogen reduction switching)
7 Three-way valve (hydrogen reduction switching)
8 Three-way valve (purge switching)
9 Pressure gauge 10 Flow meter 11 Sampling port (before reaction)
12 Sampling port (after reaction)
13 Water trap 14 Hydrogen reduction buffer gas 15 Gas circulation pump 16 Purge gate valve

Claims (6)

A catalytic activity evaluation apparatus comprising a raw material gas control means for controlling the flow rate of the raw material gas introduced into the reaction container, a reaction container having a housing portion for accommodating a plurality of catalysts, and a gas detection means for detecting a catalytic reaction product Because
The reaction vessel comprises a vessel main body having a raw material gas buffer portion and a plurality of catalyst installation portions therein, a heating portion for uniformly heating the temperature of the catalyst, and a single raw material gas introduction portion and a plurality of catalytic reaction generations. A gas outlet,
The raw material gas is introduced into each catalyst installation section through the buffer section, and after being subjected to a catalytic reaction in each catalyst installation section, is led out from the reaction vessel,
A catalytic activity evaluation apparatus characterized in that catalyst reaction product gases derived from different deriving units are respectively conducted to gas detection means via catalyst reaction product gas control means.   The catalyst activity evaluation apparatus according to claim 1, further comprising switching means for conducting a catalyst pretreatment gas in the raw material gas introduction line and the catalytic reaction product gas outlet line.   The catalyst activity evaluation apparatus according to claim 1 or 2, wherein the gas detection means is a gas detection tube.   A plurality of storage units installed under the same conditions are filled with a plurality of catalysts of the same type or different from each other, a raw material gas is introduced into the storage units, and the raw material gases and the plurality of catalysts are brought into contact under heating conditions. A plurality of gas detector tubes, each of which measures a concentration of a product gas contained in a catalytic reaction product gas derived from a different derivation unit using a plurality of gas detector tubes installed in the downstream. The catalyst activity evaluation method which carries out relative evaluation of the catalyst of 1 on the same conditions.   After introducing the catalyst pretreatment gas into the housing portion and pretreating the plurality of catalysts, the raw material gas is introduced into the housing portion and the raw material gas and the plurality of catalysts are brought into contact under heating conditions. 5. A method for evaluating catalytic activity, wherein the plurality of catalysts according to claim 4 are relatively evaluated under the same conditions.   6. The catalytic activity evaluation method for relatively evaluating a plurality of catalysts according to claim 4 or 5 under the same conditions, wherein the gas detection tube is a general-purpose gas detection tube.