KR20200131875A - Metal chloride generating device and method for producing metal powder - Google Patents

Abstract

There is provided a method for stably producing metal powder by preventing damage or destruction of a production device, a metal chloride producing device capable of realizing this method, and a metal powder producing system including a metal chloride producing device. The metal chloride generating apparatus includes a chlorinating furnace having a first heating furnace having a metal inlet for introducing metal and a second heating furnace connected to the first heating furnace, a first heater for heating the first heating furnace, and a second And a metal chloride generating device including a second heater for heating the heating furnace. The second heating furnace has an outlet for discharging the gas of metal chloride. The chlorinated furnace has a first gas inlet for introducing a gas containing chlorine, and the first gas inlet is surrounded by either the first heater or the second heater.

Description

Metal chloride generating device and method for producing metal powder

An embodiment of the present invention relates to an apparatus for producing metal chloride, a system for producing metal powder, and a method for producing metal powder using the system.

Fine metal particles (metal powders) are used in various fields. For example, powders of metals exhibiting high conductivity such as copper, nickel, and silver are used as raw materials for electronic components such as internal electrodes of multilayer ceramic capacitors (MLCC). It is widely used. Several methods of manufacturing such metal powder are known, but gas phase method is mentioned as an example. In this method, for example, as disclosed in Patent Documents 1 and 2, metal powder is formed by contacting and reducing a gas of a metal chloride with a reducing gas such as hydrogen.

(Prior technical literature)

(Patent literature)

Patent Document 1: Japanese Patent Publication No. 6-76609

Patent Document 2: Japanese Patent Laid-Open Publication No. 10-219313

One embodiment of the present invention is a method for stably manufacturing a metal powder by preventing damage or destruction of a manufacturing apparatus, a metal chloride generating apparatus capable of realizing this method, and a metal powder manufacturing including a metal chloride generating apparatus One of the tasks is to provide a system.

One embodiment related to the present invention is an apparatus for generating metal chloride. The metal chloride generating device includes a chlorinating furnace having a first heating furnace provided with a metal introduction port for introducing metal and a second heating furnace connected to the first heating furnace, a first heater heating the first heating furnace, and a second heating furnace. A second heater for heating the heating furnace is provided. The second heating furnace has an outlet for discharging the gas of metal chloride. The chlorinated furnace has a first gas inlet for introducing a gas containing chlorine, and the first gas inlet is surrounded by either the first heater or the second heater.

One embodiment related to the present invention is an apparatus for generating metal chloride. The metal chloride generating apparatus includes a first heating furnace having a metal inlet for introducing metal and a gas inlet for introducing nitrogen, and a second heating furnace connected to the first heating furnace and having an outlet for discharging metal chloride, A first heater for heating the first heating furnace, a second heater for heating the second heating furnace, and a third heater for heating nitrogen are provided.

One embodiment according to the present invention is a method of manufacturing a metal powder. The method comprises producing metal chloride by reacting metal with chlorine gas in a chlorinating furnace configured to be heated by a first heater and a second heater, and a gas containing chlorine from a first gas inlet provided in the chlorinating furnace. It involves transporting the vapor of the chloride to the reduction furnace by introducing The first gas inlet is surrounded by either of the first heater and the second heater.

One embodiment according to the present invention is a method of manufacturing a metal powder. This method includes introducing heated nitrogen into a chlorinating furnace while reacting a metal with chlorine gas in the chlorinating furnace to produce a metal chloride, and transporting the vapor of chloride to a reduction furnace using a gas containing chlorine.

One embodiment related to the present invention is an apparatus for generating metal chloride. This metal chloride generating apparatus includes a chlorinating furnace having a first heating furnace having a metal introduction port for introducing a metal, and a second heating furnace connected to the first heating furnace. The second heating furnace has an outlet for discharging a gas of metal chloride, and a first gas inlet for introducing a gas containing chlorine.

One embodiment related to the present invention is an apparatus for generating metal chloride. This metal chloride generating device includes a chlorinated furnace including a first heating furnace and a second heating furnace connected to the first heating furnace. The first heating furnace includes a metal inlet for introducing metal and a first gas inlet for introducing gas containing chlorine. The second heating furnace has an outlet for discharging the gas of metal chloride. The first gas inlet is located closer to the connection between the first heating furnace and the second heating furnace than the metal inlet for introducing metal. The metal chloride generating device may further have a first heater that heats the first heating furnace. Further, the first gas inlet may be surrounded by the first heater.

1 is a schematic configuration diagram of a metal powder production system according to an embodiment of the present invention.
2 is a schematic cross-sectional view of a metal chloride generating device according to an embodiment of the present invention.
3 is a schematic cross-sectional view of a metal chloride generating device according to an embodiment of the present invention.
4 is a schematic cross-sectional view of a metal chloride generating apparatus according to an embodiment of the present invention.
5 is a schematic cross-sectional view of a metal chloride generating device according to an embodiment of the present invention.
6 is a schematic cross-sectional view of a metal chloride generating device according to an embodiment of the present invention.
7 is a schematic side view of a metal chloride generating device according to an embodiment of the present invention.

Hereinafter, each embodiment of the present invention will be described with reference to the drawings and the like. However, the present invention can be implemented in various aspects without departing from the gist of the present invention, and is not intended to be limited to the description of the embodiments exemplified below.

The drawings may schematically show the width, thickness, shape, etc. of each part compared to the actual aspect in order to clarify the description, but this is only an example, and limiting the interpretation of the present invention no. In the present specification and each of the drawings, elements having functions similar to those described with respect to the previous drawings are given the same reference numerals, and overlapping descriptions may be omitted in some cases.

In the present specification and claims, in expressing the aspect of arranging other structures above or below an arbitrary structure, only ``above'' or ``below'' is indicated, unless otherwise stated, arbitrary It is assumed that both the case where another structure is disposed above or below the structure so as to be in contact with the structure, and the case where another structure is disposed above or below an arbitrary structure through another structure is included. In addition, the arrangement of the structure is mainly described based on the order of movement of the gas of the metal chloride, and includes a case where the structure referred to as above and the structure referred to below are, for example, located horizontally.

(First embodiment)

A metal chloride production apparatus 110 according to an embodiment of the present invention, and a metal powder production system (hereinafter, referred to only as a system) 100 including the same will be described.

1. Overall composition

1 shows an overview of the system 100 configuration. The system 100 includes a metal chloride generating device 110 and a reduction furnace 200 as a main configuration. Although not shown, the system 100 includes a recovery device such as a separation device 300 connected to the reduction furnace 200 or a bag filter connected to the reduction furnace 200 or the separation device 300. You may do it. The metal chloride generating device 110 and the reduction furnace 200 are connected by a first transport pipe 112, and the reduction furnace 200 and the separation device 300 are connected by a second transport pipe 202.

The metal chloride generating device 110 has as one of its functions to generate a metal chloride (hereinafter, simply referred to as chloride) by reaction of a zero-valent metal and chlorine gas. Chloride exists as a gas (steam) in the metal chloride generating device 110, and some of it exists as a liquid depending on the type of metal or reaction conditions. The vapor of chloride is introduced into the reduction furnace 200 through the first transport pipe 112. As the metal, copper, silver, nickel, or the like can be used. There is no restriction on the shape of the metal to be used, and for example, a pellet-shaped, wire-shaped, or plate-shaped metal can be used.

The reduction furnace 200 is connected to the first transport pipe 112, and a gas inlet (fifth gas inlet) for introducing the vapor of chloride transported from the metal chloride generating device 110 into the reduction furnace 200 It has (204). The reduction furnace 200 includes a gas inlet (a sixth gas inlet) 206 for introducing a reducing gas such as hydrogen, hydrazine, ammonia, methane, etc., which are reducing gases for reducing chloride. The chloride is reduced in the reduction furnace 200, whereby metal powder is produced. Inert gas such as nitrogen gas is introduced into the reduction furnace 200 from the outside through a gas inlet (not shown), and the metal powder produced by this is cooled and at the same time, the separation device ( 300) or transported to a recovery device.

Although detailed description is omitted, the separation device 300 has a function of purifying metal powder by removing aggregates contained in the metal powder or sintered metal by-products in the reduction furnace 200. do. The recovery device is provided for isolating the purified metal powder from nitrogen gas. Although not shown in detail in FIG. 1, as will be described later, the metal chloride generating device 110 is provided with a gas inlet for introducing various gases.

2. Metal chloride generating device

A schematic cross-sectional view of the metal chloride generating device 110 is shown in FIG. 2. The metal chloride generating device 110 is provided to surround the chlorinating furnace 120 and the chlorinating furnace 120 as a main configuration, and a first heater 160 and a second heater for heating the chlorinating furnace 120 ( 162). The first heater 160 and the second heater 162 may be independently controlled.

The chloride furnace 120 includes a first heating furnace 122 and a second heating furnace 124. In the example shown in FIG. 2, the second heating furnace 124 is located below the first heating furnace 122, but the first heating furnace 122 and the second heating furnace 124 may be horizontally disposed. Further, the reduction furnace 200 may also be provided under the first heating furnace 122 or the second heating furnace 124 (see FIG. 1), or they may be horizontally disposed. In addition, in the example shown in FIG. 2, the inner diameter of the connection part 123 between the first heating furnace 122 and the second heating furnace 124 is smaller than that of other parts, but as shown in FIG. 3, the first heating furnace 122 ) To the second heating furnace 124, the inner diameter of the chlorinating furnace 120 may be the same. Alternatively, the inner diameters of the first heating furnace 122 and the second heating furnace 124 may be different.

As an arbitrary configuration, the chlorinating furnace 120 may be provided with a partition member 126 separating the first heating furnace 122 and the second heating furnace 124 (see Fig. 3). That is, the chlorinating furnace 120 may be provided with the first heating furnace 122 and the second heating furnace 124 connected to the first heating furnace 122 by the partition member 126. The partition member 126 is provided with at least one opening, whereby the gas introduced into the first heating furnace 122 or the second heating furnace 124 and the vapor of the chloride produced by them are separated. It can pass through member 126. Although detailed description is omitted, the number, size, arrangement, etc. of the openings may be appropriately designed in consideration of reaction conditions, vapor pressure of chloride, and shape or size of the metal used. Further, when molten chloride is generated, the partition member 126 may be designed so that the liquid chloride can pass through the partition member 126. In FIG. 3, a state in which metal is disposed on the partition member 126 in the first heating furnace 122 as pellets 114 is shown.

As the material used for the chlorinated furnace 120, quartz or ceramic may be used, and may be selected in consideration of the metal used or the melting point of the chloride. Examples of the material used for the partition member 126 include oxides of metals or semimetals such as quartz, alumina, zirconia, ceramics, nitrides such as boron nitride, graphite, and the like.

As shown in FIG. 2, the first heating furnace 122 is provided with a metal introduction port 128 for introducing metal into the first heating furnace 122. The gas containing chlorine used for chlorination may be introduced into the first heating furnace 122 using the metal introduction port 128. Alternatively, a gas introduction port (third gas introduction port) 130 may be provided as an arbitrary configuration, and a gas containing chlorine may be introduced through the valve 132. The gas containing chlorine may contain nitrogen or an inert gas such as argon or helium to dilute chlorine. By using a gas containing an inert gas and chlorine (hereinafter, also referred to as a mixed gas), it becomes possible to easily and precisely control the amount of chlorine. In the example shown in FIG. 2, the third gas inlet 130 is surrounded by the first heater 160, but the third gas inlet 130 is not surrounded by the first heater 160, and the first heater ( 160) may be exposed.

The first heating furnace 122 is heated by the first heater 160, and the metal disposed in the first heating furnace 122 is introduced from the metal inlet 128 and/or the third gas inlet 130 It reacts with the chlorine gas which is used to give a metal chloride. Chloride exists as a gas (steam) in the chloride furnace 120 depending on the type of metal, or takes an equilibrium state between the gas and the liquid. In the latter case, the chloride is partly molten and partly as vapor. The molten chloride and the chloride vapor generated in the first heating furnace 122 move to the second heating furnace 124 through the connection part 123 (the opening of the partition member 126 is provided).

The second heating furnace 124 transports the vapor of the chloride generated in the first heating furnace 122 to the reduction furnace 200, and when molten chloride is generated, it vaporizes to generate the vapor of the chloride, The main function is to transport this to the reduction furnace 200. The second heating furnace 124 is heated by being surrounded by the second heater 162. As described above, the first heater 160 and the second heater 162 are independently controlled and can heat the first heating furnace 122 and the second heating furnace 124 at different temperatures. The first heater 160 and the second heater 162 are driven so that the temperature of the second heating furnace 124 is higher than the temperature of the first heating furnace 122. For example, by controlling the temperatures of the first heating furnace 122 and the second heating furnace 124 so that the temperature of the second heating furnace 124 increases by 200 to 300°C, molten chloride is generated Even when moving from the first heating furnace 122 to the second heating furnace 124, the chloride can be rapidly vaporized in the second heating furnace 124.

Further, in order to efficiently vaporize the molten chloride, the vaporization auxiliary material 140 may be filled in the second heating furnace 124. The vaporization auxiliary material 140 is, for example, an oxide of a metal or semi-metal such as quartz, alumina, zirconia, ceramics, nitrides such as boron nitride, and particles or pellets containing graphite. It can provide a large heating area for vaporization.

The second heating furnace 124 includes an outlet 134 for transporting the vapor of the chloride produced in the first heating furnace 122 or the second heating furnace 124 to the reduction furnace 200. In addition, the chlorination furnace 120, more specifically, a gas inlet for introducing a gas containing chlorine into at least one of the first heating furnace 122 and the second heating furnace 124 (first gas inlet ) (136) is provided. The first gas inlet 136 may be arranged so as to be surrounded by either of the first heater 160 and the second heater 162. In the example shown in FIG. 2, the first gas inlet 136 is provided in the second heating furnace 124 and is surrounded by the second heater 162. The first gas inlet 136 is connected to a chlorine gas source (such as a bombe) (not shown) through the valve 138 further. A gas containing chlorine introduced through the first gas inlet 136 may be used, or an inert gas may be included.

The outlet 134 for transporting the chloride vapor to the reduction furnace 200 is preferably disposed at a position higher than the bottom of the second heating furnace 124. This is to prevent the molten chloride from flowing into the reduction furnace 200 without vaporization.

When the first gas inlet 136 is provided in the second heating furnace 124, the first gas inlet 136 is located lower than the outlet 134 (a position farther than the first heating furnace 122) Can be placed on This is because the molten chloride easily collects in the lower part of the second heating furnace 124, by introducing a gas containing chlorine from the lower part of the second heating furnace 124, the gas of the chloride is efficiently discharged to the outlet 134. Because it can be introduced.

The gas containing chlorine introduced from the metal inlet 128, the first gas inlet 136, and the third gas inlet 130 imparts a positive pressure to the chlorinated furnace 120. For this reason, the vapor of the chloride produced in the chlorinating furnace 120 is introduced into the first transport pipe 112 through the outlet 134 by this positive pressure and transported to the reduction furnace 200. All or most of the chlorine introduced from the metal inlet 128 or the third gas inlet 130 is consumed by reaction with the metal. However, the chlorine introduced from the first gas inlet 136 has a small contribution to the reaction with the metal, and the consumption rate is lower than that of the chlorine introduced from the metal inlet 128 or the third gas inlet 130. small. Accordingly, the vapor of chloride is transported to the reduction furnace 200 while contacting the chlorine added through at least the first gas inlet 136.

As described above, the chloride transported to the reduction furnace 200 is reduced in the reduction furnace 200 to give metal powder. The obtained metal powder is again transported to the separation device 300 to be purified, and further isolated by a recovery device.

3. The contribution of goats

In the metal chloride generation device 110 of the system 100 of the present embodiment, a gas containing chlorine is introduced through the metal inlet 128 or the third gas inlet 130. This gas is introduced because it gives a positive pressure for chlorinating the metal and for transporting the vapor of the produced chloride to the second heating furnace 124.

On the other hand, in the metal chloride generating device 110, a gas containing chlorine is further introduced into the second heating furnace 124 through the first gas introduction port 136, and a positive pressure is applied to the chloride furnace 120. Thereby, the vapor of the chloride can be efficiently sent to the discharge port 134, and the vapor of the chloride can be quickly transported to the reduction furnace 200. As a result, it is possible to suppress an error in that chloride remains in the second heating furnace 124 or that chloride solidifies or precipitates in the second heating furnace 124 or the first transport pipe 112. In addition, it is also possible to prevent the reducing gas introduced into the reduction furnace 200 through the sixth gas introduction port 206 from flowing backward through the first transport pipe 112. For this reason, it is possible to prevent an error in that chloride is reduced in the first transport pipe 112 and metal is precipitated to clog or damage the first transport pipe 112.

Here, the gas containing chlorine introduced through the first gas inlet 136 is physically imparted to a positive pressure for simply introducing the vapor of chloride into the reduction furnace 200 through the outlet 134 as described above. In addition to the means, it functions as a chemical means to more effectively prevent the occurrence of system 100 errors, as described below.

The metal and chloride exist in an equilibrium state represented by the following equation.

[Formula 1]

For example, when the metal is copper, the following equilibrium is established.

[Formula 2]

Although it depends on the type and temperature of the metal, even if all of the metals are made of chloride in the chlorination furnace 120, in order to maintain this equilibrium, some of the chloride is reduced to metal. For this reason, metal precipitates in the second heating furnace 124 or the first transport pipe 112, which causes clogging.

However, the inventor found that by introducing chlorine gas into this balance system and shifting the balance to the right (the chloride side), it is possible to prevent the gaseous chloride from depositing as a metal. That is, since chlorine introduced through the first gas inlet 136 is hardly consumed for chlorination of the metal introduced into the first heating furnace 122, the second heating furnace 124 or the first transport pipe 112 ) Can come into contact with the vapor of chloride. For this reason, chlorine introduced through the first gas inlet 136 contributes to shifting the metal-chloride equilibrium toward the chloride side as a chemical means. As a result, metal is precipitated from the chloride gas in the second heating furnace 124 or the first transport pipe 112, thereby clogging or damage of the first transport pipe 112, and the second heating furnace 124 Errors such as destruction of) can be suppressed more effectively.

In this way, by introducing a gas containing chlorine from the first gas inlet 136 not only as a physical means, but also as a chemical means, it is possible to provide a metal powder manufacturing system that can be stably driven for a long time without damage or destruction. And further, by using this system, it becomes possible to efficiently produce metal powder.

4. Modification

The metal chloride generating device 110 is not limited to the configuration shown in FIGS. 2 or 3. For example, as shown in Fig. 4, the chlorinated furnace 120 may be provided with a plurality of gas inlets for supplying a gas containing chlorine that functions as a chemical means. Chlorine gas may be supplied together with an inert gas. In the example shown in FIG. 4, a gas introduction port (second gas introduction port) 142 for introducing a gas containing chlorine into the second heating furnace 124 is further provided. The second gas inlet 142 may be disposed above the outlet 134. That is, the second gas inlet 142 is provided so that the distance from the first heating furnace 122 to the outlet 134 is greater than the distance from the first heating furnace 122 to the second gas inlet 142 can do. The second gas inlet 142 is connected to a chlorine source (not shown), and the supply of gas containing chlorine is controlled by the valve 144.

By adopting such a structure, the contribution as a chemical means can be increased, and precipitation of metal in the second heating furnace 124 or the first transport pipe 112 can be more effectively prevented.

Alternatively, as shown in FIG. 5, the metal chloride generating device 110 may be provided with a gas inlet (fourth gas inlet) 146 and a third heater 164 for introducing a heated inert gas. . The fourth gas inlet 146 is provided in the first heating furnace 122 and is connected to the third heater 164 through a valve 148. The third heater has a function of heating an inert gas.

By supplying the heated inert gas to the first heating furnace 122, a higher positive pressure can be applied in the chlorination furnace 120 without causing a decrease in the temperature of the first heating furnace 122. For this reason, it is possible to introduce all or most of the chloride produced in the first heating furnace 122 from the second heating furnace 124 to the reduction furnace 200 through the first transport pipe while maintaining the gaseous state. It becomes. When the boiling point of the chloride is high, since it takes a relatively long time for vaporization in the second heating furnace 124, this configuration is particularly effective when producing a powder of a metal imparting a chloride having a high boiling point.

In addition, when the fourth gas inlet 146 and the third heater 164 are provided, the first gas inlet 136 or the second gas inlet 142 may not necessarily be provided (see FIG. 6). . When the boiling point of the chloride is relatively low, the system 100 can be efficiently driven by adopting this configuration, and the manufacturing cost of the system 100 can be reduced. It becomes possible to provide powder.

(Second embodiment)

In this embodiment, a method of manufacturing a metal powder using the system 100 will be described. Here, a method of manufacturing metal powder using the system 100 including the metal chloride generating device 110 shown in FIG. 2 will be described as an example. Descriptions of configurations similar to or similar to those described in the first embodiment may be omitted.

First, metal is introduced into the first heating furnace 122 through the metal introduction port 128. As described above, copper, silver, nickel, or the like can be used as the metal. The vaporization auxiliary material 140 may be previously filled in the second heating furnace 124.

Next, the first heating furnace 122 and the second heating furnace 124 are respectively heated using the first heater 160 and the second heater 162. The temperature of the first heating furnace 122 also depends on the type of metal, but can be appropriately set in the range of 800°C or more and 1,000°C or less, for example. By setting the temperature of the first heating furnace 122 to a temperature lower than the melting point of the metal, melting of the raw material metal (metal pellets 114) can be prevented. In the first heating furnace 122, the metal reacts with chlorine to give chloride.

Meanwhile, the temperature of the second heating furnace 124 may be set higher than the temperature of the first heating furnace 122. Although it depends on the type of metal, it can be set appropriately in the range of 900°C or more and 1,200°C or less, for example. By setting the temperature of the second heating furnace 124 to a temperature higher than the boiling point of the chloride, the chloride can be rapidly vaporized.

Together with the heating of the first heating furnace 122 and the second heating furnace 124, a gas containing chlorine is introduced into the second heating furnace 124 through the first gas inlet 136. Further, a gas containing chlorine is introduced into the first heating furnace 122 through the metal inlet 128 and/or the third gas inlet 130. When an inert gas is mixed with a gas containing chlorine introduced into the second heating furnace 124 via the first gas inlet 136, for example, the chlorine concentration in the mixed gas is 0.001 wt% or more and 20 wt% It may be less than or equal to 0.01 wt% or more and 10 wt% or less, or 0.1 wt% or more and 2 wt% or less. The flow rates of these gases may be appropriately adjusted according to the scale. In the case of introducing a gas containing chlorine using the second gas inlet 142 (see FIG. 4), chlorine introduced through the first gas inlet 136 and the second gas inlet 142 The composition and total flow rate of the gas to be included may be the same or different. For example, the flow rate of the chlorine-containing gas introduced through the first gas inlet 136 may be larger than the flow rate of the chlorine-containing gas introduced through the second gas inlet 142. The amount of chlorine in the chlorine-containing gas introduced into the second heating furnace 124 through the first gas inlet 136 or the second gas inlet 142 is the metal inlet 128 and/or the third gas inlet It is preferable that it is less than the amount of chlorine in the chlorine-containing gas introduced into the first heating furnace 122 via 130. Thereby, the chlorine content of the metal powder to be obtained can be reduced.

In addition, as in the example shown in Figs. 4 and 5, when the heated nitrogen gas is introduced into the first heating furnace 122, the temperature of the nitrogen gas may be, for example, 800°C or more and 1,000°C or less.

The vapor of the chloride produced in the chlorination furnace 120 is discharged from the discharge port 134 and is introduced into the reduction furnace 200 through the fifth gas inlet port 204 via the first transport pipe 112. A reducing gas selected from hydrogen, hydrazine, ammonia, methane, or the like is supplied from the sixth gas inlet 206 (see Fig. 1), and the flow rate and concentration may be adjusted so as to be greater than or equal to the stoichiometric ratio for reacting with chloride. The metal powder produced in the reduction furnace is physically transferred to a separation device 300 or a recovery device (not shown) such as a bag filter by nitrogen gas introduced into the reduction furnace 200 to be isolated. Metal powder can be manufactured by the above process.

As described in the first embodiment, the gas containing chlorine introduced from the first gas inlet 136 or the second gas inlet 142 to the second heating furnace 124 is quickly and as a physical means. Not only has a function of stably transporting the vapor of chloride to the reduction furnace 200, but also has a function of preventing metal precipitation as a chemical means. For this reason, by applying the present embodiment, it is possible to provide a metal powder production system capable of stably driving and efficiently producing metal powder.

(Third embodiment)

In this embodiment, the structure of the metal chloride generating device 116 different from that of the metal chloride generating device 110 will be described. Descriptions of configurations that are the same as or similar to those described in the first embodiment may be omitted.

The metal chloride generating device 116 has at least the first heating furnace 122 and the second heating furnace 124 having a different inner diameter, and the second heating furnace 124 has a tube shape. ) And the structure is different.

More specifically, as shown in FIG. 7, the second heating furnace 124 has a tube shape, and its inner diameter is smaller than that of the first heating furnace 122. By setting it as such a shape, it is possible to more effectively mix the vapor of chloride and the chlorine gas, and the physical and chemical effects of the gas containing chlorine introduced through the first gas inlet 136 can be increased.

The first gas inlet 136 is provided in the first heating furnace 122 and is surrounded by the first heater 160. It is preferable that the first gas inlet 136 is disposed closer to the second heating furnace 124 than the metal inlet 128. This is because when molten chloride is generated, chloride is deposited in the lower portion of the first heating furnace 122, and vaporization occurs preferentially in this portion. Therefore, as shown in FIG. 7, it is preferable to arrange the vaporization auxiliary material 140 in the first heating furnace 122 so that the upper surface is positioned above the first gas inlet 136. The pellets 114 may be disposed on the vaporization auxiliary material 140 to be in contact with the vaporization auxiliary material 140.

In this configuration, the first heater 160 and the second heater 162 are driven to heat the chlorinated furnace 120, and containing chlorine from the metal inlet 128 and/or the third gas inlet 130 By introducing the gas, a reaction between metal and chlorine gas occurs, and chloride is produced. The chloride present as vapor moves to the second heating furnace 124 through the gap between the vaporization auxiliary material 140. Meanwhile, the liquid chloride in the molten state absorbs and vaporizes the thermal energy supplied from the first heater 160 while penetrating the layer of the vaporization auxiliary material 140, and then moves to the second heating furnace 124. In this way, in the metal chloride generating device 116, the first heating furnace 122 generates chloride and vaporizes the chloride in a molten state.

Like the metal chloride generating device 110, the gas containing chlorine introduced from the first gas inlet 136 not only introduces the vapor of chloride into the second heating furnace 124 as a physical means, but also as a chemical means. It is possible to prevent metal from depositing from chloride. For this reason, precipitation of metals and chlorides can be effectively suppressed even in the tubular second heating furnace 124, and the system 100 can be stably operated without causing damage or destruction, and Powder can be provided.

Moreover, as shown in FIG. 7, the total length may be increased without increasing the occupied area by folding the tubular second heating furnace 124. When the boiling point of the chloride is high, it takes a relatively long time for vaporization in the second heating furnace 124, so this configuration is particularly effective when producing a metal powder that imparts a chloride having a high boiling point.

Example

(Example 1)

In this embodiment, an example in which copper powder is manufactured using the system 100 including the metal chloride generating device 110 having the structure shown in FIG. 2 as a basic structure will be described. Specifically, pellets of copper were placed in the first heating furnace 122 and pellets of quartz were placed in the second heating furnace 124. In this state, the first heating furnace 122 and the second heating furnace 124 were heated to 900°C and 1,150°C, respectively, using the first heater 160 and the second heater 162. A mixed gas containing nitrogen and chlorine was introduced from the metal inlet 128 and the first gas inlet 136, respectively. The chlorine concentration of the mixed gas is as shown in Table 1. In Table 1, when the flow rate of the mixed gas introduced from the first gas inlet 136 is 1.0, the flow rate ratio of the mixed gas introduced from the metal inlet 128 (that is, introduced from the first gas inlet 136) The flow rate ratio of the mixed gas introduced from the metal inlet 128 to the mixed gas) was also described. The reaction time was 10 hours.

Mixed gas flow rate and chlorine concentration Gas inlet Mixed gas flow ratio (-) Chlorine concentration (wt%) First gas inlet (136) 1.0 20 Metal inlet (128) 5.0 49

After the reaction was completed, the first heater 160 and the second heater 162 were separated, and the chloride furnace 120 was observed. As a result, it was confirmed that no deposition of copper chloride was observed in the lower portion of the second heating furnace 124, and no damage to the second heating furnace 124 occurred.

(Example 2)

In this embodiment, an example in which copper powder is manufactured using the system 100 including the metal chloride generating device 110 having the structure shown in FIG. 4 as a basic structure will be described. Specifically, pellets of copper were placed in the first heating furnace 122 and pellets of quartz were placed in the second heating furnace 124. In this state, the first heating furnace 122 and the second heating furnace 124 were heated to 900°C and 1,150°C, respectively, using the first heater 160 and the second heater 162. A mixed gas containing nitrogen and chlorine was introduced through all of the metal inlet 128, the first gas inlet 136, and the second gas inlet 142. The reaction was carried out in two steps. The flow rate of the mixed gas introduced from the second gas inlet 142 and the metal inlet 128 when the flow rate of the mixed gas introduced from the first gas inlet 136 is 1.0 and the chlorine in each mixed gas The concentration is as shown in Table 2. The first gas inlet 136 and the second gas inlet 142 are connected to the same mixed gas source, and the concentrations of each component of the mixed gas introduced from these gas inlet ports are the same. The reaction times of the first step and the second step were 9 hours and 8 hours, respectively.

Mixed gas flow rate and chlorine concentration Gas inlet Step 1 Step 2 Mixed gas flow ratio (-) Chlorine concentration (wt%) Mixed gas flow ratio (-) Chlorine concentration (wt%) First gas inlet (136) 1.0 20 1.0 20 The second gas inlet (142) 1.0 20 1.0 20 Metal inlet (128) 5.0 49 5.0 49

After completion of the reaction in each step, the first heater 160 and the second heater 162 were separated, and the chlorinated furnace 120 was observed. As a result, compared with Example 1, it was confirmed that the precipitation of metallic copper inside the chloride furnace 120 was greatly reduced. In addition, it was confirmed that the precipitation of copper inside the first transport pipe 112 also decreased.

(Example 3)

In this embodiment, the influence of the chlorine concentration of the mixed gas introduced from the first gas inlet 136 using the system 100 having the metal chloride generating device 110 having the structure shown in FIG. 2 as a basic structure Shows the result of reviewing. Specifically, pellets of copper were placed in the first heating furnace 122 and pellets of quartz were placed in the second heating furnace 124. In this state, the first heating furnace 122 and the second heating furnace 124 were heated to 900°C and 1,150°C, respectively, using the first heater 160 and the second heater 162. A mixed gas including nitrogen and chlorine was introduced from the metal inlet 128 and the first gas inlet 136. When the flow rate of the mixed gas introduced from the first gas inlet 136 is set to 1.0, the flow rate of the mixed gas introduced from the metal inlet 128 is fixed to 3.2, and the mixed gas introduced from the metal inlet 128 The chlorine concentration of the gas was fixed at 43 wt%, and the chlorine gas concentration in the mixed gas introduced from the first gas inlet 136 was changed as shown in Table 3. Experiment 3 in Table 3 is a comparative example, and is an experiment in which only nitrogen is introduced from the first gas inlet 136. The reaction time was 10 hours.

Effect of chlorine concentration in gas mixture Experiment Chlorine gas concentration ^a (wt%) Recovery ^b / target reaction ^c (%) Metal precipitation ^d One 0.9 95 n 2 1.5 95 n 3 0 75 y

^a Concentration in the mixed gas introduced from the first gas inlet

^b measured value

^c calculated value

^d n: No precipitation of copper in the chlorination furnace, y: There is precipitation of copper in the chlorination furnace

As shown in Table 3, by introducing a gas containing chlorine from the first gas inlet 136, it was found that copper powder in an amount substantially equal to the calculated value (target reaction amount) can be obtained (Experiment 1 , 2). On the other hand, when chlorine gas was not introduced from the first gas inlet 136 (Experiment 3), the amount of recovery was deviated from the target amount of reaction, and the recovery rate remained at a lower rate compared to Experiments 1 and 2. This suggests that copper is precipitated in the chloride furnace 120.

After the reaction was completed, the first heater 160 and the second heater 162 were separated, and the chloride furnace 120 was observed. As a result, when a gas containing chlorine is introduced from the first gas inlet 136, copper does not precipitate in the chlorinated furnace 120, or even if precipitated, the driving of the system 100 is not affected. Was the amount of. On the other hand, when chlorine gas was not introduced from the first gas inlet 136 (Experiment 3), it was visually observed that copper precipitated in the chlorinated furnace 120.

As can be seen from Examples 1, 2, and 3, by applying the embodiment of the present invention, metals or chlorides are deposited in the chloride furnace 120 or in the first transport pipe 112. It has been confirmed that such errors can be suppressed.

Each of the embodiments described above as an embodiment of the present invention can be appropriately combined and implemented as long as they do not contradict each other. In addition, based on the display device of each embodiment, as long as the gist of the present invention is included in the subject matter of the present invention, those skilled in the art may appropriately add, delete or change the design of components, or add, omit, or change conditions. It is included in the scope of the invention.

Even if an operation effect different from the operation effect by the aspect of each of the above-described embodiments is apparent from the description of the present specification, or what can be easily predicted by a person skilled in the art, it is naturally interpreted as being derived by the present invention.

Reference Numerals 100: metal powder production system, 110: metal chloride generation device, 112: first transport pipe, 114: pellet, 116: metal chloride generation device, 120: chloride furnace, 122: first heating furnace, 123: connection part, 124: 2nd heating furnace, 126: partition member, 128: metal inlet, 130: third gas inlet, 132: valve, 134: outlet, 136: first gas inlet, 138: valve, 140: vaporization auxiliary material, 142 : Second gas inlet, 144: valve, 146: fourth gas inlet, 148: valve, 160: first heater, 162: second heater, 164: third heater, 200: reduction furnace, 202: second Transport pipe, 204: fifth gas inlet, 206: sixth gas inlet, 300: separation device

Claims (15)

A chloride furnace having a first heating furnace having a metal introduction port for introducing metal and a second heating furnace connected to the first heating furnace,
A first heater for heating the first heating furnace, and
Including a second heater for heating the second heating furnace,
The second heating furnace includes an outlet for discharging the gas of the metal chloride,
The chlorinated furnace includes a first gas inlet for introducing a gas containing chlorine,
The first gas inlet is surrounded by one of the first heater and the second heater,
Metal chloride generating device. The method of claim 1,
The first gas inlet is provided in the second heating furnace, and is disposed farther from the first heating furnace compared to the outlet. The method of claim 1,
The first gas inlet is provided in the first heating furnace,
The first gas inlet is closer to a connection portion between the first heating furnace and the second heating furnace than the metal inlet. The method of claim 2,
The second heating furnace further includes a second gas introduction port for introducing a gas containing chlorine,
The second gas inlet is disposed closer to the first heating furnace than the outlet,
Metal chloride generating device. The method of claim 1,
The second heater is configured to heat the second heating furnace to a temperature higher than the temperature of the first heating furnace. The method of claim 1,
The first heating furnace further includes a third gas introduction port for introducing a gas containing chlorine,
The third gas inlet is exposed from the first heater,
Metal chloride generating device. The method of claim 1,
The first heating furnace,
A fourth gas inlet for introducing nitrogen, and
Having a third heater for heating the nitrogen,
Metal chloride generating device. The method of claim 1,
The second heating furnace has an inner diameter smaller than that of the first heating furnace. Reacting a metal with chlorine gas in a chlorinating furnace configured to be heated by a first heater and a second heater to produce a chloride of the metal, and
Including transporting the vapor of the chloride to the reduction furnace by introducing a gas containing chlorine from the first gas inlet provided in the chlorination furnace,
The first gas inlet is surrounded by one of the first heater and the second heater,
A method of manufacturing metal powder. The method of claim 9,
The furnace of chloride,
A first heating furnace surrounded by the first heater, and
A second heating furnace connected to the first heating furnace and surrounded by the second heater,
The method further comprises vaporizing the chloride in the second heating furnace,
Way. The method of claim 10,
The method, wherein the vaporization of the chloride performed in the second heating furnace is performed at a temperature higher than a temperature at which the chloride is produced. The method of claim 10,
The method, wherein the first gas inlet is provided in the first heating furnace. The method of claim 10,
The method, wherein the first gas inlet is provided in the second heating furnace. The method of claim 13,
The transport of the vapor of the chloride to the reduction furnace is performed through an outlet provided in the second heating furnace,
Introduction of the gas containing chlorine is performed using the first gas inlet and a second gas inlet provided in the second heating furnace,
Way. The method of claim 10,
The method further comprising introducing heated nitrogen into the first heating furnace.

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