Synthesis reactor for carbon nanomaterials

Abstract

The present invention relates to a carbon nanomaterial synthesis apparatus. The carbon nanomaterial synthesis apparatus of the present invention comprises a horizontally rotating reactor that provides a space for synthesizing carbon nanomaterials and forms a certain length, a plate-shaped scraper formed along the longitudinal direction of the reactor with one end positioned to abut the inner wall of the reactor, and a gas supply pipe coupled to the other end of the scraper and having nozzles formed at predetermined intervals along the longitudinal direction, wherein both ends of the gas supply pipe are fixed by an external support, and when the reactor is horizontally rotated during synthesis, the scraper fixed to the gas supply pipe scrapes the inner wall to remove deposits attached to the inner wall during the synthesis of carbon nanomaterials in the reactor.

Description

Technology Field

[0001] The present invention relates to a carbon nanomaterial synthesis apparatus, and more specifically, to a carbon nanomaterial synthesis apparatus mounted inside a horizontal rotary reactor that can synthesize carbon nanomaterials of uniform quality by efficiently removing wall deposits on the inner wall of the reactor and uniformly supplying a synthesis gas. Background Technology

[0003] Carbon nanomaterials, such as carbon nanotubes and carbon nanofibers, are undergoing extensive technological development both domestically and internationally because they can simultaneously realize various properties that surpass the limitations of existing materials, thanks to their nanoscale diameters, excellent mechanical and electrical conductivity, and linear shape characteristics where length is long relative to diameter.

[0004] As such, various studies are being conducted on the development of reactors and processes to mass-produce carbon nanomaterials with uniform quality that possess excellent physicochemical properties and can be endowed with multifunctionality.

[0005] Synthesis methods for carbon nanotubes include Thermal Chemical Vapor Deposition (CVD), Plasma Chemical Vapor Deposition (PVD), Arc Discharge (AVA), and Laser Vaporization; currently, Catalyst Chemical Vapor Deposition (CCVD) is the mainstream method for the mass production of carbon nanotubes.

[0006] Conventional carbon nanotube synthesis devices using the catalytic chemical vapor deposition method can be broadly classified into vertical fluidized bed reactors and horizontal rotary reactors. In particular, horizontal rotary reactors face problems such as deterioration of catalyst and carbon nanotube flowability, non-uniform quality of carbon nanotubes, and limitations in continuous operation due to reactants adhering to the interior of the reactor during the carbon nanotube synthesis process.

[0007] Numerous patent documents related to such carbon nanotube synthesis devices have been disclosed. Korean Patent Publication No. 10-2024-0043342 describes a carbon nanotube synthesis device and method in which a catalyst and a reaction gas are simultaneously injected into an inclined rotary reactor,

[0008] Korean Patent Registration No. 10-1097906 describes a carbon nanotube synthesis apparatus in which a catalyst is supplied to the center of a fixed-bed horizontal rotating reactor while a reaction gas is supplied from one side of the reactor.

[0009] Korean Patent Registration No. 10-0712690 describes a loop-type carbon nanotube mass synthesis device that generates carbon nanotubes while an introduced catalyst and reaction gas circulate and flow inside a reactor,

[0010] Korean Patent Publication No. 10-2023-0055993 describes a carbon nanotube manufacturing apparatus comprising a series-connected plasma device and a CVD reactor,

[0011] Korean Patent Publication No. 10-2024-0022895 describes an apparatus and method for synthesizing carbon nanotubes by reacting a carbon source-containing gas with a vaporized metal catalyst that is dispersed in a 360° direction using thermal plasma.

[0012] Korean Patent Registration No. 10-2030215 describes an apparatus and method for synthesizing carbon nanotubes in a vertical reactor using plasma,

[0013] Korean Patent Registration No. 10-1282308 presents a carbon nanotube synthesis device that allows catalyst pretreatment, carbon nanotube synthesis, and cooling to be carried out sequentially in different temperature ranges inside a rotary horizontal reactor.

[0014] Conventional devices for synthesizing carbon nanotubes present methods for synthesizing carbon nanotubes by configuring the reactor in a vertical or horizontal direction or by supplying reaction methods, catalysts, and reaction gases; however, there have been no reports regarding a device for removing deposits inevitably generated by reactions inside the reactor.

[0015] Accordingly, the applicant proposes a carbon nanomaterial synthesis apparatus capable of continuously producing high-quality carbon nanotubes by mounting a gas supply pipe, in which a deposit removal device and a nozzle are integrated, on the inner surface of a horizontal rotary reactor. Prior art literature

[0017] 1. Republic of Korea Patent Publication No. 10-2024-00433422. Republic of Korea Patent Registration No. 10-10979063. Republic of Korea Patent Registration No. 10-07126904. Republic of Korea Patent Publication No. 10-2023-00559935. Republic of Korea Patent Publication No. 10-2024-00228956. Republic of Korea Patent Registration No. 10-20302157. Republic of Korea Patent Registration No. 10-1282308 The problem to be solved

[0018] The problem that the present invention aims to solve is to provide a carbon nanomaterial synthesis apparatus capable of efficiently removing deposits inside a horizontal rotary reactor that inevitably occur, while simultaneously supplying reaction gas uniformly inside the reactor.

[0020] The problems of the present invention are not limited to those mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below. means of solving the problem

[0022] To solve the problem described above, a carbon nanomaterial synthesis apparatus according to one embodiment of the present invention comprises a horizontally rotating reactor that forms a certain length and provides a space for synthesizing carbon nanomaterials, a plate-shaped scraper formed along the longitudinal direction of the reactor with one end disposed to abut the inner wall of the reactor, and a gas supply pipe coupled to the other end of the scraper and having nozzles formed at predetermined intervals along the longitudinal direction, wherein both ends of the gas supply pipe are fixed by an external support, and when the reactor is horizontally rotated during synthesis, the scraper fixed to the gas supply pipe scrapes the inner wall to remove attachments attached to the inner wall during the synthesis of carbon nanomaterials in the reactor.

[0024] Specific details of other embodiments are included in the detailed description and drawings. Effects of the invention

[0026] In a carbon nanomaterial synthesis apparatus according to one embodiment of the present invention, when the reactor is rotated horizontally during synthesis, a scraper fixedly coupled to a gas supply pipe scrapes the inner wall to remove deposits attached to the inner wall of the reactor during synthesis.

[0027] In addition, by attaching a weight-bearing member to one side of the scraper, the scraper can continuously remove attached material by contacting the reactor wall at regular intervals during horizontal rotation of the reactor.

[0028] In addition, nozzles are formed at preset intervals in the gas supply pipe, allowing gas to be supplied uniformly to the entire inner surface along the length of the reactor.

[0029] In other words, by ensuring that there are no deposits from the start of carbon nanotube synthesis until the end of synthesis, and by supplying the reaction gas uniformly inside the reactor to improve the reaction efficiency of the synthesis gas, high-quality carbon nanotubes can be manufactured economically.

[0031] The effects according to the present invention are not limited to those exemplified above, and other effects will be clearly understood by those skilled in the art from the description in the specification below. Brief explanation of the drawing

[0033] FIG. 1 is a cross-sectional view of a carbon nanomaterial synthesis apparatus according to one embodiment of the present invention. FIG. 2 is a drawing for explaining the structure of an attachment removal device (1000) according to one embodiment of the present invention. FIG. 3 is a diagram illustrating the synthesis of carbon nanomaterials using a carbon nanomaterial synthesis apparatus according to one embodiment of the present invention. Figure 4 is an SEM image of carbon nanotubes synthesized by a carbon nanomaterial synthesis apparatus according to one embodiment of the present invention. Specific details for implementing the invention

[0034] The following description merely illustrates the principles of the invention. Therefore, those skilled in the art may invent various devices that embody the principles of the invention and are included within the concept and scope of the invention, even if they are not explicitly described or illustrated in this specification. Furthermore, all conditional terms and embodiments listed in this specification are, in principle, explicitly intended only for the purpose of understanding the concept of the invention and should be understood as not being limited to the embodiments and conditions specifically listed as such.

[0035] Furthermore, in the following description, ordinal expressions such as "first," "second," etc., are intended to describe mutually equal and independent objects, and should be understood as having no meaning of main / sub or master / slave in their order.

[0036] The aforementioned objectives, features, and advantages will become clearer through the following detailed description in conjunction with the attached drawings, and accordingly, a person skilled in the art to which the invention pertains will be able to easily implement the technical concept of the invention.

[0037] The features of each of the various embodiments of the present invention may be combined or combined with one another, either partially or wholly, and as will be fully understood by those skilled in the art, various technical interlocking and operation are possible, and each embodiment may be implemented independently of one another or together in an interlocking relationship.

[0038] Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings.

[0040] As catalyst particles, which are raw materials for the synthesis of carbon nanomaterials, flow along the walls of the horizontal reactor and come into contact with the reaction gas, a phenomenon occurs in which some of the carbon nanomaterials from the initial synthesis also adhere, along with the formation of deposits due to the thermal reaction between the catalyst and the iron-based reactor material on the reactor surface.

[0041] If these deposits are not removed, they will gradually build up and obstruct the flow of catalysts and synthesized carbon nanomaterials inside the reactor. Therefore, the removal of deposits from the reactor walls is a critical factor in determining product quality and operational efficiency.

[0042] Accordingly, we aim to provide a carbon nanomaterial synthesis apparatus that ensures there are no deposits from the start of carbon nanomaterial synthesis until the end of synthesis, while simultaneously supplying reaction gas uniformly inside the reactor.

[0043] FIG. 1 is a cross-sectional view of a carbon nanomaterial synthesis apparatus according to one embodiment of the present invention. FIG. 2 shows the structure of an attachment removal device (1000) according to one embodiment of the present invention.

[0044] Referring to FIG. 1 and FIG. 2, a carbon nanomaterial synthesis apparatus according to one embodiment of the present invention may include a reactor (100) and an attachment removal device (1000) disposed inside the reactor (100), and the attachment removal device (1000) may include a scraper (200), a weight-bearing member (300), a gas supply pipe (400), and a nozzle (500).

[0045] The reactor (100) provides a space for synthesizing carbon nanomaterials and can be formed to a certain length.

[0046] The scraper (200) is formed along the longitudinal direction of the reactor (100) and can be positioned so that one end, that is, one end in the width direction, contacts the inner wall of the reactor (100). At this time, it is positioned at a distance that does not interfere with the horizontal rotation of the reactor (100) so as to remove attachments from the inner wall.

[0047] Additionally, on one side of the scraper (200) (the rear side of the scraper in FIG. 2), a weight-bearing member (300) and a gas supply pipe (400) that provide self-weight may be combined.

[0048] The weight-bearing member (300) is attached to the rear of the scraper, and load is applied to the scraper (200) so that one end of the scraper (100) can maintain a certain distance so as not to interfere with the horizontal rotation of the reactor (100).

[0049] Additionally, the gas supply pipe (400) is connected to the rear end area of ​​the scraper (200), and nozzles (500) can be formed at predetermined intervals along the longitudinal direction.

[0050] As shown in FIGS. 1 and 2, the nozzle (500) is configured along the longitudinal direction of the gas supply pipe (400) and can be connected to the gas supply pipe (400) at a certain angle. Accordingly, the carbon nanotube synthesis gas injected from one direction of the gas supply pipe (400) is uniformly supplied into the reactor (100) through each nozzle (500) and can come into constant contact with the catalyst moving within the horizontal rotary reactor (100).

[0051] Additionally, both longitudinal ends or one end of the gas supply pipe (400) may be fixed by an external support (such as a fixed frame that does not hinder the rotation of the gas supply module or the reactor), and when the reactor (100) is rotated horizontally during synthesis, one end of the scraper (200) fixed to the gas supply pipe (400) scrapes the inner wall of the reactor (100), thereby removing the deposits attached to the inner wall during the synthesis of carbon nanomaterials in the reactor (100).

[0052] At this time, the carbon nanomaterial can be at least one of carbon nanotubes, carbon nanofibers, and graphene.

[0053] In addition, the carbon nanomaterial synthesis apparatus according to one embodiment of the present invention can synthesize carbon nanomaterials based on any synthesis method such as chemical vapor deposition, chemical vapor grown, plasma synthesis, or metal vapor deposition.

[0054] FIG. 3 is a diagram illustrating the synthesis of carbon nanomaterials using a carbon nanomaterial synthesis apparatus according to an embodiment of the present invention. Hereinafter, the synthesis of carbon nanotubes can be described as an example.

[0055] Figure 3(a) illustrates the synthesis of carbon nanotubes using a horizontal rotary reactor (100). The method of synthesizing carbon nanotubes in the horizontal rotary reactor (100) involves synthesizing carbon nanotubes through a Counter Flow reaction in which a reaction gas is supplied from the opposite direction while a catalyst is loaded.

[0056] At this time, the catalyst charged flows along the wall of the reactor heated to a high temperature and reacts with the carbon nanotube synthesis gas supplied from the opposite direction, thereby synthesizing carbon nanotubes. Since the material of the reactor is iron (Fe)-based, a small amount of carbon nanotubes are synthesized on the inner surface of the reactor and begin to adhere to the wall. As synthesis progresses, they grow larger, which obstructs the flow of the catalyst and carbon nanotubes, and at the same time, causes the distribution of the synthesis gas reacting with the catalyst to become uneven.

[0057] In order to solve the above problems, the carbon nanomaterial synthesis apparatus of the present invention can synthesize carbon nanomaterials by installing an attachment removal device (1000) inside the reactor (100) as shown in Fig. 3 (b).

[0058] Specifically, a plate-shaped scraper (200) is installed longitudinally at a location that does not obstruct the flow of carbon nanotubes and catalyst, as shown in (b) of FIGS. 1 and FIGS. 3, so that it can be removed from the initial stage of attachment formation by contacting the inner wall of the reactor (100). At this time, it is important to maintain the distance that contacts the wall.

[0059] In addition, a weight-applying device (300) capable of generating self-weight can be mounted on the scraper (200) to apply weight to the scraper (200) so that it can remove the attached material by scraping the wall surface consistently, taking into account the strength of the attached material when it is formed. Through this, the inner wall surface of the reactor (100) can always maintain its initial surface state during the carbon nanotube synthesis process.

[0060] In the carbon nanotube synthesis method based on catalytic chemical vapor deposition, the gas supply device for synthesis is typically installed at the reactor inlet to supply gas at a constant pressure and flow rate, allowing it to pass through the reactor and react with the catalyst. At this stage, controlling the synthesis gas to ensure uniform contact with the catalyst determines the quality and productivity of the carbon nanotubes.

[0061] To this end, in the present invention, as shown in FIGS. 1, 2 and 3(b), the gas supply is not provided from the conventional reactor inlet as in FIGS. 3(a), but rather a nozzle (500) with an angle is configured at regular intervals along the length of the gas supply pipe (400) mounted on the scraper (200) to ensure constant contact with the catalyst moving within the horizontal rotary reactor (100). Through this, the utilization rate and reaction efficiency of the synthesis gas in contact with the catalyst are improved, thereby enabling the economical synthesis of carbon nanotubes of uniform quality.

[0062] When carbon nanotubes were synthesized using a carbon nanotube synthesis apparatus according to an embodiment of the present invention under conditions of a catalyst loading amount of 1 g / min, a synthesis temperature of 700°C, and a synthesis gas supply amount of ethylene (C2H4) of 10 L / min, it was confirmed that the deposits on the walls of the reactor (100) were effectively removed by the deposit removal device (1000), allowing for smooth flow of the catalyst and carbon nanotubes, and that the synthesis gas was also supplied uniformly to the entire interior of the reactor. In a conventional reactor without a deposit removal device (1000) (Fig. 3 (a)), the formation of deposits on the walls of the reactor and non-uniformity of the synthesis gas flow occurred.

[0063] Table 1 below compares the amount of attached material, carbon nanotube synthesis, and the utilization rate of synthesis gas before (Fig. 3 (a)) and after (Fig. 3 (b)) installing a gas supply pipe (400), i.e., an attached material removal device (1000), which has a scraper (200), a weight-bearing member (300), and a nozzle (500) formed therein according to one embodiment of the present invention, in the reactor (100) of a carbon nanomaterial synthesis device.

[0064] Attachment removal device (1000) attachment Carbon nanotube synthesis amount (%) Syngas utilization rate (%) Before installation is 92 35 After installation doesn't exist 95 66

[0065] FIG. 4 is an SEM image of carbon nanotubes synthesized by a carbon nanomaterial synthesis device according to one embodiment of the present invention. As shown in FIG. 4, it can be confirmed that carbon nanotubes of uniform quality are synthesized in a reactor (100) equipped with an attachment removal device (1000) according to one embodiment of the present invention.

[0066] In this way, when the reactor of the carbon nanomaterial synthesis apparatus according to an embodiment of the present invention is rotated horizontally during synthesis, a scraper fixedly coupled to the gas supply pipe scrapes the inner wall to remove deposits attached to the inner wall of the reactor during synthesis.

[0067] In addition, by attaching a weight-bearing member to one side of the scraper, the scraper can continuously remove attached material by contacting the reactor wall at regular intervals during horizontal rotation of the reactor.

[0068] In addition, nozzles are formed at preset intervals in the gas supply pipe, allowing gas to be supplied uniformly to the entire inner surface along the length of the reactor.

[0069] As a result, the reaction efficiency of the synthesis gas can be improved by ensuring that there are no deposits from the start of carbon nanotube synthesis until the end of synthesis, and by ensuring that the reaction gas is supplied uniformly inside the reactor.

[0070] In this way, the carbon nanomaterial synthesis apparatus according to the embodiment of the present invention can economically produce high-quality carbon nanotubes by resolving problems such as the internal adhesion phenomenon of the conventional reactor and low gas efficiency.

[0072] It goes without saying that various embodiments of the present invention may be combined with one or more others to form a new embodiment.

[0074] A carbon nanomaterial synthesis apparatus according to various embodiments of the present invention comprises a horizontally rotating reactor that provides a space for synthesizing carbon nanomaterials and forms a certain length, a plate-shaped scraper formed along the longitudinal direction of the reactor with one end disposed to abut the inner wall of the reactor, and a gas supply pipe coupled to the other end of the scraper and having nozzles formed at predetermined intervals along the longitudinal direction, wherein both ends of the gas supply pipe are fixed by an external support, and when the reactor is horizontally rotated during synthesis, the scraper fixed to the gas supply pipe scrapes the inner wall to remove attachments attached to the inner wall during the synthesis of carbon nanomaterials in the reactor.

[0075] According to another feature of the present invention, a weight-bearing member that provides self-weight may be attached to one side of the scraper.

[0076] According to another feature of the present invention, the carbon nanomaterial may be at least one of a carbon nanotube, a carbon nanofiber, and graphene.

[0077] According to another feature of the present invention, the carbon nanomaterial can be synthesized based on chemical vapor deposition, chemical vapor grown, plasma synthesis, or metal vapor deposition.

[0079] Furthermore, although embodiments of the present invention have been described in more detail with reference to the attached drawings, the present invention is not necessarily limited to these embodiments and may be modified in various ways within the scope of the technical spirit of the present invention. Accordingly, the embodiments disclosed in the present invention are intended to explain, not limit, the technical spirit of the present invention, and the scope of the technical spirit of the present invention is not limited by these embodiments. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. The scope of protection of the present invention shall be interpreted by the claims below, and all technical spirits within the equivalent scope shall be interpreted as being included within the scope of rights of the present invention. Explanation of the symbols

[0081] 100 : Reactor 1000 : Attachment removal device 200 : Scraper 300 : Weight-imposing member 400: Gas supply pipe 500 : Nozzle

Claims

Claim 1 A carbon nanomaterial synthesis apparatus comprising: a horizontally rotating reactor forming a certain length and providing a space for synthesizing carbon nanomaterials; a plate-shaped scraper formed along the longitudinal direction of the reactor, with one end positioned to abut the inner wall of the reactor; and a gas supply pipe coupled to the other end of the scraper, with nozzles formed at predetermined intervals along the longitudinal direction; wherein both ends of the gas supply pipe are fixed by an external support, and when the reactor is horizontally rotated during synthesis, the scraper fixed to the gas supply pipe scrapes the inner wall to remove deposits attached to the inner wall during the synthesis of carbon nanomaterials in the reactor. Claim 2 A carbon nanomaterial synthesis apparatus according to claim 1, wherein a weight-bearing member that imparts self-weight is coupled to one side of the scraper. Claim 3 A carbon nanomaterial synthesis apparatus according to claim 1, wherein the carbon nanomaterial is at least one of carbon nanotubes, carbon nanofibers, and graphene. Claim 4 A carbon nanomaterial synthesis apparatus according to claim 1, wherein the carbon nanomaterial is synthesized based on chemical vapor deposition, chemical vapor grown, plasma synthesis, or metal vapor deposition.

Images