JP5335589B2 - Manufacturing method of molded body - Google Patents

Description

  The present invention relates to a method for producing a molded body such as a catalyst or a catalyst carrier having an end surface curved in a convex shape.

  Patent Document 1 describes a catalyst having an end face whose shape is curved in a convex shape. According to Patent Document 1, such a catalyst is more active than a catalyst having a spherical shape, a cylindrical shape, a spoke ring shape, etc., the ease of filling in a multi-tubular reactor, the catalyst bed pressure, It is said to have many characteristics required as industrial catalysts such as loss and high strength. Patent Document 2 also describes a catalyst having a similar shape.

  However, since the catalyst having the convex end face as described above is manufactured by a tableting molding method, there is a problem that productivity is low, and it is difficult to put it to practical use. In particular, in the tableting molding method, it has been difficult to produce a small-diameter molded body having an outer diameter of 3 mm or less.

  Therefore, development of a manufacturing method for efficiently producing a catalyst whose end surface is curved in a convex shape is desired.

Japanese Patent Laid-Open No. 6-145093 JP 61-141933 A

  An object of the present invention is to provide a method for producing a molded body such as a catalyst whose end face is curved in a convex shape with high productivity.

  As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention intermittently extrude the extruded product from the entire circumference toward the axis while continuously extruding the molding material with a die. When the molded body is cut by ejecting a fluid pulse at a predetermined pressure from a slit having a predetermined width, the molded body whose end face is curved in a convex shape without being deformed or damaged, particularly The present inventors have found the fact that small-diameter molded bodies can be efficiently produced with high productivity and have completed the present invention.

That is, the manufacturing method of the molded object which concerns on this invention consists of the following structures.
(1) A fluid pulse consisting of a mixture of gas and liquid intermittently from the slit from the entire circumference of the extruded molded body toward the axial center while continuously extruding the molded body from the extrusion port provided in the die of the extruder. In which the discharge pressure of the fluid pulse is 0.1 MPa or less and the width of the slit for ejecting the fluid pulse is 1. The manufacturing method of the molded object which has an end surface curved in convex shape characterized by being larger than 5 mm.
(2) The said die is a manufacturing method of the molded object of the said (1) description provided with the rod which does not protrude from the said slit through the said extrusion port.
(3) A sensor for detecting the length of the molded body extruded from the extrusion port of the die is provided, and ejection and stop of the fluid pulse based on an input signal from the sensor, and in the extrusion flow path of the extrusion molding machine The manufacturing method according to (1) or (2) above, wherein the length of the molded body is adjusted by adjusting the output of the flow rate control means provided in.
(4) The said molded object is a manufacturing method of the molded object in any one of (1)-(3) whose outer diameter is 3 mm or less.

ADVANTAGE OF THE INVENTION According to this invention, there exists an effect that the molded object which has an end surface curved to convex shape, especially a small diameter molded object can be efficiently manufactured by extrusion molding with high productivity. In addition, the resulting molded body is high in strength, and when filled into various containers such as a fixed bed reactor and reaction tube as a catalyst, contact between the molded bodies, and the molded body and the inner wall of the reaction tube By the contact, the end surfaces of the molded bodies do not break or chip, so that there is no increase in pressure loss and the effect of improving the reaction results can be obtained.
In addition, the length of the molded body to be manufactured is detected by a sensor, and the length of the molded body can be freely adjusted to adjust the output of the flow control means provided in the flow path in the extrusion molding machine and the start and stop of the fluid cutter. It becomes possible to adjust to.

It is principal part sectional drawing which shows an example of the shaping | molding apparatus for enforcing the manufacturing method of this invention. It is explanatory drawing which shows the whole shaping | molding apparatus for enforcing the manufacturing method of this invention. (A) And (b) is the top view and front view which respectively show an example of the molded object obtained with the manufacturing method of this invention. (A) And (b) is explanatory drawing for demonstrating an example of the method of cut | disconnecting a molded object with a fluid pulse, respectively in the manufacturing method of this invention.

  The method for producing a molded body according to the present invention is to produce a molded body having a convexly curved end face, while continuously extruding a cylindrical molded body from an extrusion port provided in a die of an extruder. Then, fluid pulses composed of a mixture of gas and liquid are intermittently ejected from the entire circumference of the extruded molded body toward the axial center, and the molded body is cut into predetermined dimensions to obtain a molded body.

  First, the molding apparatus used in the present invention will be described with reference to FIGS. As shown in FIG. 2, the molding apparatus 10 includes an extruder 11 and a die 12 attached to the tip of the extruder 11. The molded body 16 extruded from the die 12 is dried by a dryer 15. The extruder 11 may be anything as long as it can press the molding material to a predetermined pressure, or heat and pressurize it and extrude it from the die 12. For example, a screw extruder or the like is used.

  As shown in FIG. 1, the die 12 has a cylindrical shape having an extrusion port 20 at one end. In this embodiment, a center bar 21 (bar body) is provided at the center of the extrusion port 20 in order to produce a hollow product. The center bar 21 is fixed to the inner surface of the die 12 by a plurality of supports radially arranged at the rear end (left side in FIG. 1). The front end protrudes forward from the extrusion port 20 of the die, and a slit 29 described later. It extends to.

  The tip of the die 12 is formed in a conical shape. A ring-shaped holding member 26 is attached around the outer surface, and a bottomed cylindrical cap 28 provided with a conical bottom 27 is screwed around the outer surface. An opening 29 having substantially the same diameter as the extrusion port 20 of the die 12 is formed at the center of the bottom of the cap 28. The center bar 21 passes through the die extrusion port 20, and its front end does not protrude from the opening 29 of the cap 28. The center bar 21 can adopt various shapes as its cross-sectional shape, and examples thereof include a circle and an ellipse. A contact portion 30 protruding radially inward is provided on the proximal end side of the holding member 26, whereby an annular gap 31 is formed between the inner surface of the holding member 26 and the outer surface of the die 12. Further, a conical gap 32 is also formed between the inner surface of the conical bottom 27 of the cap 28 and the tip of the die 12, and the inner peripheral side of the gap 32 is opened to form an annular slit 33. ing. As described above, the outer surface of the die 12, the holding member 26, and the cap 28 constitute the fluid cutter 13 including the slit 33. The width of the slit 33, that is, the opening length in the extrusion direction is not particularly limited, but is preferably 1.5 mm or more and 5 mm or less, and preferably 2 mm or more and 4 mm or less. A liquid supply pipe 35 and a gas supply pipe 36 are connected to the holding member 26. A fluid pulse of mist is ejected from the slit 33 by the liquid and gas supplied from the pipes 35 and 36.

  As shown in FIG. 2, the gas supply pipe 36 is connected to a gas supply device 39 (including a gas pressurization device and a pump) via an electromagnetic valve 37. The liquid supply pipe 35 is also connected to the liquid supply device 42 via an electromagnetic valve 37 '. Further, in the vicinity of the outside of the opening 29 of the cap 28 shown in FIG. 1, the length of the molded body 16 cut to a predetermined length by the fluid cutter 13 and pushed forward through the opening 29 is detected. The sensor 40 for this is installed. This sensor 40 is a drive source 41 for driving the electromagnetic valve 37 of the gas supply pipe 36, the electromagnetic valve 37 ′ of the liquid supply pipe 35, and the flow rate control means 14 (flow rate control valve or the like) provided in the flow path in the extruder 11. The motor is electrically connected to a motor or the like, and is configured to control the opening / closing of the solenoid valve 37 and the solenoid valve 37 ′ and the driving of the drive source 41 based on a detection signal from the sensor.

The time during which the solenoid valve 37 and the solenoid valve 37 ′ are open varies depending on the extrusion speed of the extruder 11 and the viscosity of the extruded material, but is usually about 0.05 to 1.0 seconds, and ejects a fluid pulse. It is preferable that the interval to be performed is about 0.1 to 10 seconds. The discharge pressure of the fluid pulse is preferably 0.1 MPa or less.
As for the flow rate control means 14, when a plurality of dies 12 are attached to one extruder 11, and the length of the molded body 16 is longer than a set value, the flow rate control means 14 is within the flow path of the extruder 11. When the flow rate of the flow control means 14 is widened to slow down the flow rate of the molded body 16, on the contrary, when the length of the molded body 16 is shorter than the set value, Control is performed so that the opening degree is widened and the flow rate of the molded body 16 is increased. However, when there is one die 12 for the extruder 11, the screw rotation speed of the extruder 11 may be controlled instead of the control by the flow rate control means 14.

Next, a method for producing a molded body having an end surface curved in a convex shape using the molding apparatus 10 configured as described above will be described. As shown in FIG. 1, when the soft molding material is extruded by the extruder 11, a cylindrical continuous molded body having a through hole determined by the outer diameter of the center rod 21 is extruded from the extrusion port 20 of the die 12. The extrusion pressure of the continuous molded body is not particularly limited, but is preferably about 1.0 to 3.0 MPa, preferably about 1.5 to 2.5 MPa.
The electromagnetic valves 37 and 37 'are opened by the sensor 40 that detects the length of the molded body when it is pushed out to a predetermined length, and gas (pressurized air or the like) passes through the gas supply pipe 36 and liquid (pressurized water or the like). ) Are supplied through the liquid supply pipes 35, mixed in the gaps 31 and 32, and then ejected from the slits 33 as mist fluid pulses. In this case, the mixing of the gas and the liquid is suitably about 1: 0.01 to 1:10 by volume ratio.

  At this time, since the outer periphery of the continuous molded product 52 is almost hermetically surrounded by the bottom of the cap 28 and the center hole is closed by the central rod 21, the continuous molded product 52 is cut by the pressure of the fluid pulse. Then, the cut molded body 16 jumps out of the opening 29 by the fluid pressure. Thereafter, the next continuous molded product is extruded as described above.

  When the continuous molded product is cut using the fluid pulse in this manner, the cutting is completed almost instantaneously, so that the shape does not collapse even before drying or even with the continuous molded product. Moreover, since it cut | disconnects before drying, cutting waste does not generate | occur | produce.

  Furthermore, in this embodiment, as shown in FIG. 3, the molded body 16 obtained by cutting a continuous molded product using a fluid pulse has a through hole 60 and the end surface 61 is curved in a convex shape. Yes. Regarding the mechanism by which the cut end surface 61 is curved in a convex shape, as shown in FIG. 4A, a fluid pulse (indicated by an arrow A) ejected obliquely from the slit 33 is applied to the continuous molded product 62. It is considered that this is because the continuous molded product 62 is cut into a V shape or a U shape.

  Also, when the fluid pulse is ejected vertically from the slit 33 onto the continuous molded product, as shown in FIG. 4B, the continuous molded product 62 is formed in a V shape or a U shape as indicated by the arrow A. In order to cut in this way, it is considered that a molded body 16 having a cut end surface curved in a convex shape is obtained.

  In order to curve the cut end face of the molded body 16 in a convex shape, it is preferable that the discharge pressure of the fluid pulse is 0.1 MPa or less and the width of the slit for ejecting the fluid pulse is larger than 1.5 mm. When the discharge pressure exceeds 0.1 MPa or when the slit width is 1.5 mm or less, it becomes impossible to obtain the molded body 16 in which the cut end surface is sufficiently curved.

  Further, it is preferable that the center rod 21 extending forward through the extrusion port 20 does not protrude from the slit 33 in order to obtain the molded body 16 whose cut end surface is sufficiently curved. The reason is that if the center rod 21 remains inserted into the molded body 16 that has been cut through the slit 33, the molded body 16 is difficult to jump out of the opening 29, so that the cut end surface is sufficiently convex. This is because the curved molded body 16 may not be obtained.

  The type, composition, and the like of the molding material for producing the molded body 16 in the present invention are not limited at all, and may be appropriately selected depending on the application. For example, when the molded body 16 is used as a catalyst, a heteropolyacid composed of a metal oxide such as alumina, silica, and titania, a composite metal oxide mainly composed of molybdenum, cobalt, bismuth, etc., molybdenum, vanadium, phosphorus, etc. Etc. can be used. When the molded body 16 is used as a catalyst carrier, cordierite, mullite, pseudoboehmite, silica / alumina, zirconia, magnesia spinel, soot-alumina, silica and the like can be used. When the molded body 16 is used as an adsorbent, a drying material, a humidity control material, etc., activated carbon, silica gel, activated alumina, silica / alumina, zeolite, smectite, apatite, diatomaceous earth, or the like can be used. Moreover, the molded object 16 can also be formed using various plastic materials etc. besides these materials.

  The molded body 16 obtained by the present invention is used as a catalyst, a catalyst carrier, an adsorbent, a desiccant, a humidity control material, and the like. In particular, when used in various forms of catalytic reactions as a catalyst or catalyst carrier, in view of more effectively utilizing the effects of the present invention, it may be used by filling a reactor or container such as a fixed bed reactor. preferable. That is, since the molded body 16 has an end surface that is curved in a convex shape, there is an effect that the corners are not lost during filling and pressure loss can be suppressed to a small level as in the conventional case. Even when the reaction tube is filled in the reaction apparatus, the catalyst performance can be efficiently expressed.

  In the above embodiment, the cylindrical or ring-shaped molded body 16 is manufactured. However, for example, a columnar molded body having no through hole can be manufactured in the same manner.

  In the above embodiment, a mixture of air and water is used as the fluid pulse, but other gases and liquids may be used depending on the type of the molded body. For example, nitrogen gas and water, nitrogen gas and organic solvent, etc. are mentioned. In the above-described embodiment, the length of the molded body is detected by the sensor 40 and the cutting of the molded body is adjusted. For example, a fluid pulse is ejected at a predetermined time interval by a timer, a sequencer, or the like. May be.

  Further, in the above-described embodiment, one die 12 is attached to one extruder 11, but it is preferable to attach and use a plurality of dies 12 for mass production. Further, the extrusion direction may be extruded not only in the horizontal direction but also downward. In the above-described embodiment, the surface of the die 12 is used for the fluid cutter. However, it can of course be provided separately from the die.

  As described above, the manufacturing method of the present invention can be manufactured with high productivity because the end surface is curved in a convex shape and the molded body can be obtained by extrusion molding, and the outer diameter is 3 mm or less. The body can also be easily manufactured.

DESCRIPTION OF SYMBOLS 10: Molding apparatus, 11: Extruder, 12: Die, 13: Fluid cutter, 14: Flow control means, 15: Dryer, 16: Molded body, 20: Extrusion port, 21: Center rod (rod body), 26 : Holding member, 28: cap, 29: opening, 31: gap, 32: gap, 33: slit, 35: liquid supply pipe, 36: gas supply pipe 37: solenoid valve, 37 ': solenoid valve, 39: gas Supply device 42: Liquid supply device

Claims (4)

While extruder continuously extruded extrusion port or RaNaru features provided on the die, intermittently jetting the fluid pulse consisting of a mixture of gas and liquid from the slit towards the axis from the entire circumference of the extruded molded body And a molding method for cutting the molded body for each predetermined dimension,
A method for producing a molded body having a convexly curved end surface, wherein the discharge pressure of the fluid pulse is 0.1 MPa or less and the width of the slit for ejecting the fluid pulse is larger than 1.5 mm.   The said die is a manufacturing method of the molded object of Claim 1 provided with the rod which does not protrude from the said slit through the said extrusion port.   A sensor for detecting the length of the molded body extruded from the extrusion port of the die is provided, and the fluid cutter is started and stopped based on an input signal from the sensor and provided in the extrusion flow path of the extrusion molding machine. The method for producing a molded body according to claim 1 or 2, wherein the length of the molded body is adjusted by adjusting an output of the flow rate control means.   The method for producing a molded body according to any one of claims 1 to 3, wherein the molded body has an outer diameter of 3 mm or less.

Images