DE2213285A1 - Method and device for the production of metallic powder and metals made therefrom - Google Patents

Description

Method and device for the production of metallic powder and metals made therefrom

In the process for the production of elementary metal powders, in particular refractory and refractory metals, in which a plasma reactor is used, the reacting feed material is in the reaction zone of the reactor introduced and the effluent from the reaction zone is passed into a quench zone through a selectable variable Opening or passage in a way that separates the metallic particles from the outflow allowed hot gas flow and a continuous accumulation of the metal powder in a collection zone in which the metal powder has selected properties that are controlled by maintaining certain operational parameters

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be, with these operational parameters a selected differential pressure of the medium in the jitter zone as well as the Include reaction and collection zone temperatures. The device for carrying out the process is described as well as the metals themselves.

This invention includes a method and apparatus for making elemental metallic powders. The invention is directed primarily to, but not limited to, refractory metals that are difficult to melt. Such refractory Metals are, for example, thantalum, tungsten, molybdenum and columbium. In particular, the invention relates to a method and apparatus for producing highly pure elementary metallic powders selected Properties with the highest yield and selected particle size, Shape and surface conditions, all of this in a commercially exploitable manner.

The invention further particularly relates to methods and apparatus for making elemental metallic powders directed that use or employ a plasma reactor to carry out the reaction.

For example, metallic halogens, oxides and nitrites are converted into elemental metals using a plasma reactor

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reduced and presented in a relatively pure form in amounts that were not possible before.

In the physics of gas discharges it is known to use means for carrying out chemical reactions which use a plasma flow or jet. The chemical reactions that take place in this invention are primarily reductions of metallic compounds with reducing agents such as hydrogen or carbon. Other reactions are obvious to the person skilled in the art if the description is continued.

The temperatures generated in a plasma reactor are relatively high and the reactions taking place therein are consequently not primarily more commercial For a number of reasons, the most common of which are that the reactors do could not support sustained reactions without, for example, the anode chamber in a detrimental manner to clog, or it was only possible to produce quantities of the desired end products on a laboratory scale, which, in most cases, were not of the quantity or quality found in the commercial version the process was required, or because the product lacked certain essential properties, e.g. size and Shape of the product particles.

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The present invention provides a method and an apparatus for the production of elemental metals Groups IVb, Vb and VIb of the periodic table, in which a compound of these metals in a high temperature reaction zone is brought about, which is produced by a plasma generator, in a way that has not been done beforehand achieved amounts of the metal with selected particle size in a satisfactory purity to produce thus making the metals produced usable and suitable for various commercial purposes. The individual powder are also claimed.

For example, there is currently a commercial need for thantalum powder in substantially pure form, which has a particle size large enough to cover electrodes for dry or liquid capacitors Type. The elemental metal, such as thantalum, which is based on the invention described here is obtained corresponds to the quality required for capacitors.

In the formation of the elemental thantalum, a metallic halogen, such as thantalum pentacloride, is in one Plasma reactor reduced, a reducing agent such as hydrogen is used, with this Process the purity of the thantalum obtained is very high.

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The particle size of the metal is total in a commercially feasible and possible method selection

controlled, with copious amounts of the elemental metal being obtained with great yield.

The object of the present invention is to provide a method and a device for the production of elemental metals to accomplish.

Another object of the invention is to provide a method and an apparatus for converting metal powder maintain high purity and continue to create unique metal powders.

Furthermore, a purpose of the present invention is to provide a method of an apparatus for the manufacture of to create elementary metal powders of selected particle size, shape and surface conditions.

A far what? The purpose of this invention is to be seen in a method and an apparatus for the production to create elementary metal powder, possibly a plasma reactor is used to maintain a reduction reaction.

It is also an important purpose of this invention

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To represent elemental metal powders of selected particle size using a plasma in which a selected fluid pressure control between a hot zone and a recovery zone is maintained to achieve the desired End product.

It is also a more specific object of this invention a method and an apparatus for reducing metallic compounds to the elemental metallic form to create in a plasma reactor.

Another purpose of the invention is to provide a method and an apparatus for reducing metal Halogens, Oxides and Nitrites in the elemental metal.

It is further a purpose of this invention to provide a method and an apparatus for the reduction of metals To create halogens in a plasma reactor, in which the reacting agents are in a reaction zone of the plasma reactor are introduced and the elemental metals are collected in a collection zone.

It is further an object of this invention to provide a method and apparatus for making elemental metal to create in a plasma reactor in which the

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Effluent from the reaction zone flows through a collection zone, in which the differential pressure and the selected control Temperature between these zones allows the formation of metal particles in a selected range.

It is also a specific object of the invention to provide a method and an apparatus for reducing refractories to create heat-resistant metal connections, e.g. Thantalum, tungsten, molybdenum and cplumbium compounds, which are converted into the elementary metallic state in which these metals are of high purity and selected Particle size are.

It is also an object of the invention to provide a plasma reactor process for the production of elementary To create metals in which the reacting metal is introduced after the anode of the reactor and the effluent from the reactor through a selectively variable passage in a selected controlled manner into a collection zone is directed and guided, in which the elementary metal is collected.

It is a further purpose of the invention to provide a method and an apparatus for reducing metallic halogens, e.g. columbium pentacloride or thantalum pentachloride,

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in a hydrogen plasma reactor process to create "in which the metallic compound is introduced after the anode and the effluent from the reaction zone by a temperature gradient zone within which a Collector is arranged, is guided to the passage for the outflowing medium through this temperature gradient zone to vary.

Other purposes and advantages of the invention will become apparent from the following description and accompanying drawings apparent, which are only exemplary in nature.

Basically, the method of the invention encompasses one Embodiment a method for the production of elemental metals, in which a reactive substance in a plasma reactor is introduced after the anode of the reactor and the effluent from the reaction zone through a variable passage is guided in a selectable controlled manner into a collecting zone in which the elementary metal is obtained in relatively pure form and with a certain particle size, while the selection control of the effluent Stroms is maintained.

One measure for carrying out the above method is the use of a plasma reactor device which has the.

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Reaction of a reactor chamber with a cathode and a Comprises anode, within which a plasma arc is generated, a reaction zone is in communication with this reactor chamber, into which the reactive material supplied is introduced after the anode. A deterrent, comprising the reaction zone element directs the flow of effluent through an aligned channel, and Collection means are arranged within the quenching element and the channel, thereby making a selectable variable To form a passage through which the effluent flows. As the elementary metal accumulates on the collecting elements, while maintaining a selected differential pressure between the reaction zone and the collection zone and selected temperatures in the reaction and Sairmel zones, a selected reaction product from the Outflow received.

In the drawing show:

Fig. 1 is a flow chart for the practice of a method of the invention;

Fig. 2 schematically shows the example of a device for the practice of in ^ 'ig. 1 method shown,

Fig. 3 is a partial view of a plasma reactor, the one

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specific embodiment of the invention "used,

FIG. 4 is a partial view similar to that in FIG. 3, but modified for the practice of the invention on an ongoing basis,

Fig. 5 to 8 including microscopic photographs of various Enlargement showing the thantalum powder of the invention and

9 "to 12 including" comparative microscopic representations of the well-known thantalum with corresponding enlargements for the purpose of differentiation of the thantalum according to the invention of the "known.

To introduce and better understand the scope and the breadth of the invention is intended to be a brief general description of the method and apparatus of the invention are given.

Referring to Figs. 1 and 2, a specific method of the process of the present invention and an example apparatus used for carrying out the method according to the invention is shown. The plasma generator 2 is generally of the conventional type having the commonly used cathode and anode, the

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is suitably connected to a power source, so that a potential in the region of the anode zone 4 is established. The introduction of a stabilizing or inert gas or a reactive gas into the anode zone 4 produces a reactive plasma generally within the anode zone 4 which extends axially downwards in the direction of the arrow pointing in * ⁿ ig. 2 is shown.

So far the described 'plasma generator corresponds to that known type, but is modified so that a feed material comprising a refractory metal compound from which the elemental metal is to be obtained, is introduced via the entrance 6 itself (or in some Cases with introduction by a carrier gas, as will be seen later), so that the feed material is guided below the anode and approximately and approximately into the generated plasma. Introducing the Feed material in this way effectively prevents the. Build-up of reaction products on the anode surface.

If a stabilizing gas is used to generate the plasma, the carrier gas can be used for the feed material also contains a reaction gas, such as hydrogen, for example, the refractory metal all compound being reduced. is, and / or a reaction gas can be in the vicinity of the

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Point of introduction of the feed material through the reaction gas inlet 8 will be introduced. The material supplied and the reaction gas are carried through the plasma into which an axially extending reaction element 1o protrudes. The element 1o consists of a material that is preferably inert to reactants and reaction conditions is (such a material can be tungsten, for example). Other refractory metals will also suffice and will continue to do so selected for their ability to withstand the high temperatures encountered; if they don't aerode and contaminate the elemental metals to be represented.

The organ 10 generally delimits the main reaction zone 12, from which effluent flows through the lower section 14 of the organ 1o into the collecting system, which in general at 16, and through an outlet 18 provided in the wall of the quenching member 2o.

As shown, the reaction zone 12 and a collection zone 22 are within the boundary of the quench member 20 of the usually liquid-cooled type. The collection system 16 in this example comprises a cylindrical can-like element 24 from FIG inert material, the walls of which extend upwardly in substantially liquid-tight contact with a horizontal section 15, which is outwardly directed

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Wall 14 of the organ 1o. Inside the sleeve 24, which is in generally delimiting the collection zone 22, the other section of the collection system 16 is arranged, whereby'das Collective closure element 26 has a peripheral edge 25. It should be noted that a temperature gradient between the extended upper portion of the link 1o and the inclined wall portions 14 is obtained.

The collecting cap 26 is of substantially cup shape and has a larger peripheral formation, which is with the wall portions 14 of the element 1o coincides A support member 28 on the B _o d _e of the collecting n fixed 26 and extends through an opening 3o disposed at the bottom of the quenching element 2o is provided in a manner that allows axial movement of the collecting container 26 in the seal of the arrow substantially over the entire length of the sleeve 24. Theoretically, the member 1o together with the inner surface of the collecting container 26 generally defines the limits of the Reaction zone 12, although the main reaction of the reactants takes place above the collecting vessel 26.

For obvious reasons, the materials of construction of the element 1o, at least the interior of the

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Sleeve 24, the collecting container 26 and the support element 28 made of inert materials with respect to the reaction conditions, .Reaktionspartner and the elementary obtained Metals.

In the practical process in which the device shown schematically is used, a gap forms between the horizontal wall section 15 and the edge 25 of the collecting element 26 have a passage 32 which can be selected is variable to the effluent flow from the rectification zone church to control outlet 18. The passage 32 can be due to the axial movement of the sump 26 can be selectively varied for a purpose to be described later will be.

At the beginning of the procedure, organ 26 is arranged in such a way that that the passage 32 is about 0.03i2 - 0.5 inches in size with an initial gap of about 0.15 inches, which is generally sufficient. After a certain Particulate lethal begins to run out of time Outflow flowing through the passage 32 in a manner as shown by the arrows, in the form of a sponge build up and over the edge 25 and it grows up to the outer boundaries of the inner wall of the sleeve or sleeve 24, as can be seen from the drawing. The sponge is initially approximately pancake-shaped and

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because of its location prevents the discharge from flowing through passage 32, however, fulfills an important one Puncture insofar as the discharge, if erx through the Gaps in the pancake (donut) flows, even more metal particles settle and so greater recovery permitted. /

The support member 28 is periodically moved axially downward to keep the passage 32 large enough to to allow the passage of the discharge and further build-up of the metallic sponge, its height or Depth extends essentially over the entire length of the sleeve 24, thereby producing what is called Metallic sponge can be viewed in the shape of an elongated pancake (elongate donut) in irregular cylindrical shape

Upon completion of the cycle, the collector 16 can be removed from the perimeter of the quenching element 2o and the particulate metal from inside the can and the surface of the collecting container 26 can be scraped or scraped off. The recovered metal is from exceptionally high purity and has unique properties, whereby the particle size (Fisher Sub sieve particle size) extends within a range of about 0.5 - 12 microns or is larger than that of

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depends on the conditions under which the cluster was built. In general, particle sizes are between one and ten microns. As will be explained in more detail below, the particle size of the recovered ' Metal can be selected to be controlled by varying the size of the passage 32 through which the outflow the plasma reactor passes.

In some cases it is desirable to obtain even smaller metal particles, or products are desired which are reintroduced themselves as feed material or in connection with other feed material. Of the Flow or waste effluent is removed from the system through outlet 18 and may be passed to suitable heat exchangers, Separators or other conventional recovery apparatus are fed, if only as feed material is introduced, the refractory metal particles are formed as larger particles of selected size, e.g. about 10 microns in size.

The plasma generator should be set up so that one neutral gas temperature is obtained in the plasma reactor, which is high enough (2000 K. - 5000 K) to achieve the desired get chemical reaction. In the crucible, the reaction is carried out under atmospheric pressure or slightly above it .

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Various gases can be used to stabilize the plasma, such as inert gases, e.g. helium or Argon, or reactive gases, e.g. Hydrogen, nitrogen or methane. The type of stabilizing gas that is used in the creation of the plasma is used, and the power consumption of the generator necessarily determines the temperatures that are generated here will.

The power input into the plasma generator determines the largely the intensity of the reaction that is generated in the plasma stream, and can be varied taking into account of the aforementioned criteria.

In order to get proper mixing and bring the feed into the reaction zone, it has been found to be proven beneficial to use a carrier or feed gas. This feed gas can be one of the stabilizing agents mentioned above It can be gases, or it can be a reactive gas, such as hydrogen if the reduction a metallic connection is intended. Therefore, in some cases, one of the reactants, such as hydrogen, can be used to generate the Generate plasma flow and also carry the starting material into the reactor. This is particularly desirable if when taking the method according to the invention as a basis high yields are obtained when excess is present

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stoecheometric amounts of hydrogen necessary for the Reduction can be used.

If a refractory metal compound, for example. Thantalum pentachloride to be converted into thantalum by reduction with hydrogen gas depends on the ease and the amount of conversion from the excess hydrogen ratio over the stoecheometric amount that is required for essentially complete conversion of the thantalum pentachloride to thantalum metal to obtain. Preferably an excess of hydrogen is used which is essentially complete Conversion is effected at the particular reduction temperatures and pressures employed. £ in hydrogen About 5- ^ 5 times excess at an average from about Ίο - 12 times the stoichiometric amount at a temperature range of approximately 25oo ° K - 3,000 ° K allow essentially complete conversion.

Preheating the stabilizer gas and / or the feed or carrier gas can be useful under certain conditions be. In general, preheating is not necessary. However, if desired, the starting material in the introduce the vapor state with a carrier gas, It may be necessary to preheat the carrier gas in order to bring the starting material into the gaseous state.

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However, it has been found that the gaseous state and / or the preheating of the starting material or the carrier gas is not necessary.

The starting material that is taken into account in practice can be metal present in particulate form - that as waste or by-product obtained in other processes or as a by-product in practicing any of the invention Processes in which it is desirable to obtain substantially larger particle sizes than the smaller one Particle size of the starting materials. ■: · ■

In other cases, as is generally more contemplated, the reactive starting material may be a refractory material _; be metallic compound from which the desired metal is to be recovered. Such metals to be recovered generally include those mentioned above, specifically thantalum, molybdenum, tungsten, and columbium or niobium. The halogens of these metals as well as the oxides are also suitable and include such exemplary compounds as thantalum pentachloride, columbium pentachloride, tungsten tachloride and molybdenum pentachloride. However, other chlorides such as Ti Cl ^ Hf Cl ^ jVCl ₄ , WCIg, and similar compounds can also be used. In general, any of the known and presented in chemistry is sufficient.

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presented compounds to the requirements of the process according to the invention. Therefore, the reduction to metals using carbon, sodium or the like is also intended. The hydrogen reductions of ammonium paramolybdate KinOgMOn 0 ^ ₁ , - 4 ^H 2 ° J and tungsten trioxide J WO, J, as well as the carbon reduction of the oxides are clear.

The purity of the obtained by the process according to the invention Metal powder depends to a large extent on the purity of the reactants, i.e. those that are difficult to melt Metal starting materials, the refractory metal compounds and the other reactants, such as the reducing agents, e.g., hydrogen. Also the materials from which the reactor and the apparatus in which the process takes place play an important role. As cheap have proven the materials which are usually used at high temperatures and which are essentially are chemically inert and resistant to the reactants under certain process conditions with the special raw materials.

Preferably, the reactor and collector sections of the device are made from or with the metals that are to be recovered, or they consist of one of the others commonly traded

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refractory metals such as tungsten. To the The device should ensure high purity before starting the method according to the invention be cleaned with an inert cleaning gas such as argon or helium. These facts are also well known in metallurgy like others and need not be further elaborated here.

In -B'ig. 3 is a specific apparatus and method for carrying out an embodiment of the invention. The reactor 4o is shown as a conventional type, which has the usual reactor head 42 (only the anode section is shown). The anode assembly 44 is suitably water cooled and is arranged in axial alignment with the feed sleeve 46, which is also is water cooled by means of the water inlet 48 and suitable water lines, not shown. The cuff 46 is annular and has an inner lining 5o of an inert material, such as Boron nitride, covered. The food or raw material may be introduced through the feed sleeve 46 by a series of channels or a feed channel 52. The introduction of additional reducing material, stabilizing gas or the like through the channels (not shown) can also be provided, although the inlets for the stabilizing gas and the reducing agent are provided in the reactor head 42 above the anode structure 44 and here

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are not shown.

Beneath the anode assembly 44 is the quench vessel or tank 54 of the conventional water-cooled type, which is provided with the water inlet 56 and the water outlet 58, so that the cooling medium in conventional t / ice can circulate. In the V / and of the quench tank 54, an observation opening 6o can be provided. Other observation opening ^ those in general at 62 are arranged and are not shown, can also be provided so that it is possible to the interior the quench chamber 54 to be observed. The quenching chamber 54 is liquid-tight with the reactor head 42 connected by means of a head piece 64 in a conventional manner and provided with a bottom 66, the one has removable cover 68 which is provided with a through hole 7o, the purpose of which will be described later shall be. The outlet 7 ^ is at the Side wall of the quenching chamber 54 is arranged.

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Maintaining) the anode assembly 44 and the sleeve 46, a reaction zone is arranged, generally with ", wherein the reaction zone comprises a neck-shaped element 74 with an upper splash portion 76, the one from the support collar 78 »the one for this purpose is provided, is supported. With the lower end of the neck-shaped element 74 of the organ 72 is a container 80 connected by a bell-shaped shape, which is arranged over the neck 74, so that the end portion 82 of the neck 74 protrudes into the interior of the container 80. The container 80 is shown here in a manner that it is supported by a plate 84. The plate 84 is provided with a central opening 86, the size and shape of which corresponds to the circumferential shape of the container 80.

The plate 84 is supported on the inner wall 88 of the quench tank 54 by means of a support ring 90 which welded or otherwise to the inner surface communicates.

__ -_-- ⁼ and Within the interior of the quench tank 54 / below the plate 84 is a liner 92 which comprises a tubular sleeve with a carbon wall 94 and the inner lining 96 of an inert material. The chuck 92 may be supported by the ground support ring 98 in the manner shown.

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The collecting container is within the limits of the feed 92 100 generally cup-shaped arranged, which has a flange 1o2 and is supported on the floor by means of the rod 1o4, the is attached by means of the sleeve and pin assembly 1o6. The rod 1o4 extends through the bore 7o into the removable cover plate 68 and supports the container 1oo in an axially displaceable manner, so that the container 1oo to

there

Plate 84 / and moved away from it in the axial direction essentially over the entire length of the chuck 92 can. It should be noted that the surface of the plate 84 facing inward toward the container 1oo is, with the outer surface 1o8 of the approach 1o2 forms a passage or opening generally indicated at 11o.

The neck 74, the bell-shaped element 8o, the plate 84, the collector 1oo, the rod 1o4, the sleeve and pin arrangement 1o6 as well as the inner lining 96 are preferably made of a refractory material, or a material which is inert with respect to the reaction conditions carried out in the reactor 4o, and that under the high temperatures and the high medium flow conditions does not erotate. Preferably it is tungsten a suitable material, but also other materials such as molybdenum and the like., suffice.

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The neck member 74, the bell-shaped member 80 and the Collecting vessels 100 generally define a high temperature or reaction zone 112 in which, for example a hard-to-melt metallic compound is reduced by a reducing agent such as hydrogen will. Most of the chemical activity takes place within the neck 74. However, the reaction can be grind of the turbulent conditions within zone 112 also take place over the entire area. The collection container I00 in connection with the point 84 and the inner lining 96 form a so-called collection zone 114, which in the is substantially within the range of the opening or the outflow passage 11 o.

In practice, energy is applied to the reactor, to create a plasma substantially in area 116 near the feed inlet (or inlets) 52. So that an easy observation through the observation openings, which are located substantially at 62, a gas such as hydrogen, be introduced into or into these openings so that the openings are cooled sufficiently to allow a visual Observe the interior of the quench tank 54 above and below the plate 84 to allow. If the feed material is introduced directly into the plasma, for example a Food material such as thantalum pentachloride, which is produced by a

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Carrier gas, such as argon, is carried due to the reducing agent and the extremely high temperature a chemical reaction within zone 112 and preferably within the confines of the neck member 74 instead.

An effluent from and within the reaction zone 112, the vaporous elemental thantalum, hydrogen, hydrogen Chloride from the reduction reaction as well as unchanged thantalum pentachloride and argon flows off the boundaries of the neck 74 over a temperature gradient or temperature drop in the bell-shaped element 80, where due to the substantial pressure and temperature difference a deposition of elemental thantalum takes place. The outflow or the outflow passes through the passage 110 down the length of jacket 92 and then out through outlet 71 of the retainer tank for further treatment and / or recovery procedures.

When the reaction is initiated, the sump is I00 arranged with respect to the inner surface of the plate 84 so that by a gap of about 1/8 inch between the inner surface 108 (Fig. 3) of the edge 102 and the inner surface the plate 84 to create. When the outflow follows the path previously described, the elementarthantal begins

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on the inner surfaces 1o8 of the edge 1o2 in significant To form quantities. Awake. A certain time is about pancake shaped (donut) thant al sponge formed, who tries to completely open the gap or passage 11ο to block and prevent the outflow from spreading to such an extent that a back pressure builds up within the rection zone 112-developed. When this happens, will the collecting container 1oo (by hand or otherwise) displaced axially downwards by means of the rod 1o4 so as to have one Pressure difference between the reaction zone 112 and the To maintain the interior of the element 92 or the collecting zone 112, which is about 0.5-5 "o pcuii & o / incL" is, with a preferred range between 2 and 3 -poiin-ds / inch '" A corresponding instrumentation, not shown, is provided for this purpose. When the thantalum sponge starts to form and grow, more and more elementarthantal is gained, and the outflow must now also flow through the interstices of the porous sponge of the elemental metal in order to deposit more elemental metal.

In the device according to FIG. 3, the maintenance of the method is continued until the collecting container 100 up to or close to the lower band of the lining 92, in which case the reactor 40 is switched off and it is now possible for him to cool off. Thereafter, the bottom plate 68 is removed and the thantalum sponge from the

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Collector 1oo, the inner lining 96 and, if necessary, the taken out other inner surfaces of the device and scraped out. The size of the reclaimed thantalum is considerably larger than that previously known in Sub-microparticles are recovered in a manner that is obtained in considerable quantities with an overall yield of about 90% and Obtained with the highest purity. The refractory and other metals also have unique physical properties Properties that were previously used in elementary metal production have not been observed.

In fig. 4 is a similar type of reactor as in FIG. 3 schematically shown; However, it differs from this in that, instead of like the reactor 40, it only operates gradually and gradually the black fusible metal allows the representation as a reactor designated in the figure with 140 of the refractory metal allowed continuously.

The structure of the reactor 140 is essentially the same as that of the reactor 40, except for the changes described later. The reactor head has been omitted as this structure is essentially the same as that of the plasma reactor 40. In this example, it can be noted that the neck member 142 is slightly shorter than that before and the top member 144 is slightly different in shape from the bell-shaped Element 80 of the apparatus previously described. A ver

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The shortened formation zone for the metallic sponge is achieved by the provision of a shortened lining 146, which by means of the support elements 143 and 150 from the inner walls of the quench tank is held.

A collector 152 is compared with the collector 100, which was previously described, substantially completely cylindrical
educated.

When the elementary metal has settled in the form of a pancake-shaped (donut) sponge or a porous cylinder (outside the collector 152 in the dot-dash position) essentially over the length of the lining 146, the collector 152 becomes the dot-dashed line Shifted position and it a number of rods 156 are brought into the position shown. If the header 152 upward into the extended position in solid lines again reached ge, the rods applied to the sponge and break it free from the collector 152 from oder'schaben it so that it falls to the bottom of the quench tank, where a is arranged via feet supported receptacle or a bowl 158, which receives the stripped metal sponge.

In this way, there is cooling of the reactor 140 after each Formation of a sponge is not necessary and the actual limitation the continuous operation of the reactor

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is the fit of the collecting container or pan 153 However, it can, and this is quite obvious to the person skilled in the art, an automatic conveyor, a conveyor belt or the like, may be provided to both the pan 158 as well as the elemental metal from the ground accumulated in it of the quench tank without any difficulty.

As was the case with reactor 40, rods 156 and pan 158 are made of an inert material such as tungsten so that the recovered elemental metal is not contaminated. The operation of the device 140 is essentially the same as it applies to the previously described device with the differences described above.

A plasma generator was constructed according to those contained in the prior art Guidelines constructed and was in axial conformity with a feed ring plate or an element, Arranged as shown at 46, made of stainless steel consist and have four feed material inlets, which are arranged angularly offset as shown in FIG. As a ring-shaped Insert was placed near the feed ring 46, which is made of boron nitride and has an inner diameter of 0.5 inch, a lower thickness of 0.125 inches and a length of 1 inch, and generally in 3 is designated by 50.

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A neck member 54 was formed on the graphite spacer 78 Tungsten supported, its inner diameter 2.1875 inches, the wall thickness 0.0937 inches and the length approximately 3.25 inches fraud.

A bell-shaped organ 80 made of tungsten with approximately 4.5 inches inside diameter and length of approximately 3.25 inches with a wall thickness of 0.125 inches was arranged as shown in FIG. 3 so that the lower portion of the Neck 7 ^ approximately 1.5 inches into the bell-shaped element 80 protruded into it.

The bell-shaped element 80 was supported on the plate 84, which was made of tungsten 0.125 inches thick, 11.5 inches in diameter, and a central opening of 4.5 inches which opened an opening into the interior of the bell-shaped organ 80 . The plate 84 was supported within the quench chamber 5 ^ by a corrosion-resistant steel ring 90 measuring 1/4 by 1/2 inch, which was welded firmly to the inner wall of the quench tank 54.

The putter 92 included a 0.375 inch graphite sleeve 94 Wall thickness and was approximately 6.375 inches in diameter with an approximate length of approximately 12 inches. An inner patch 96 of tungsten about 0.02 inches thick the interior of the element 92. The element 92 was

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by means of a corrosion-resistant steel ring, as in 98 and in 3 shown supported.

The sump or element 100 comprised a pot approximately 4.5 inches in inside diameter, 4.0 in length inches and was made of tungsten with a wall thickness of 0.125 inches. The support rod 104 was a tungsten shaft 0.375 inch diameter which is attached to the container 100 by means of a tungsten bushing and tenon arrangement 106 was connected, as shown essentially in the figure. The outlet 71 from the quench tank 54- through which the effluent was about 1.0 inch in diameter.

Using the apparatus described above, a A series of experiments were performed varying the outflow passage 110 from approximately 1/8 to 1/4 inch around the Differential pressure between the reaction zone, essentially at 112 and the collection zone 114 within the interior of the liner 92. This procedure worked also affect the temperature conditions within the reaction zone 112. By changing the passage 110 were Choose larger or smaller elementary metal particles due to the formation of a metallic sponge cylinder of about 15 cm in diameter, 2 era thick and a length that depends on the length of each experiment varied.

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The average temperature conditions in the reaction zone 112 are so calculated that they were within a range of about 18CX) to 285O ⁰ C, and the temperature of the outflow or waste or excess flow were measured as within a range of 200 to 55O ⁰ C. From the quench tank outlet 71 the effluent was passed through a cyclone recovery apparatus of the conventional type to obtain additional submicron sized elemental metals.

It was found that the formed on the spot elementary metal sponge has individual particles that form a Possess contracting properties to create interconnected particles that form a porous structure and which, after grinding and sifting, create elementary particles or powders from 1 to 10 microns in size that are permeable to gas using the Fisher sub-sieve-sizer technique is determined. The unique formation of the metallic sponge was to be determined by means of micrographic recordings, which clearly show the unique structural characteristics of that obtained in practice according to the invention previously described elemental metals.

An analysis of the various metals obtained shows that refractory metals of the highest purity are obtained have been. To determine in different cases v / elches

_ Xk. _

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Material was collected in the metallic sponge, samples were determined to be exposed to X-rays, identified as molybdenum, thantalum or tungsten, which have a cubic or crystalline structure.

When using the reactor already described, as already mentioned, a series of process runs were carried out, to get the elemental thantalum. The food or the supplied material was thantalum pentachloride and the results are exactly in the following Tables I, II and III.

- 35 2098A1 / 0752

Table I.

try

No.

power

KV (gross)

76.6 71.4 63.0

65.5

62.2

65.2

66.4

65.8

64.8

64.5

61.8

65.0

61.6.

64.4 GAS

KW 'total calculation Reaction

(net) effective, - temperature o _K degrees # -

26.6 37.7 2870

26.7 37.4 2956

26.5 42.0 2600

40.6 62.2 2980

35.4 56.6 2825

37.8 58.0 2850 37.8 57.0 2886 37.0 56.3 2865

30.5 47.0. 2800 _: 36.1 "55-8 2842

34.7 56.1 2800 37.2 57.2 2856

36.4 51.5 2710

34.2 53-1 2800

/ 1/4 »tungsten rods in the outflow stream were arranged below the collecting container

t total conversion including fixed parts in the range of 62 - 98.2 #

H ₂ rod.
River, SCTH Eats rager
Current, SCJFH N) 663 148 (He) I3285 663 178 (He) 800 266 (He) • 883 198 (Ar) 883 198 (Ar) 883 198 (Ar) 88.3 198 (Ar) 883 198 (Ar) 773 198 (Ar) 883 198 (Ar) 833 198 (Ar ") 883 198 (Ar) 883 ' 198 (Ar) 883 198 (Ar) *. '.

Portion of table I Infeed and recovery

O try
No. Meal amount Meal time
Ta, IbA std. 0.47 Gesa
engl • CD
M. A. 32.6 0.75- 7.74 jr » B. 17.3 0.67 6.59 G 21.8 0.21 7.41 O
^ 3 D. 43.4 0.48 4.52 ro E. 12.5 0.48 4.06 j? 18.3 0.28 4.43 G 23.6 0.37 3.41 H 21.8 0.36 4.08 I. 16.7 0.35 4.12 J 21.2 0.34
0.37 3.76 K
L ⁺ 21.1
24.0 0.40 3.67
4.58 M ⁺ 24.3 0.42 4.88 N ⁺ 22.0 4.73

engl. Pound English pound

# the convertible,

d.theoretical possible,

(t)

in sponge form

6.67 1 * 07 86.2 4.15 1.88 63.0 4.13 3.34 56.0 1 ^ 98 0.84 44.0 2.97 0.71 73.2 3.55 0.48 80.3 2.72 0.29 80.3 2.51 1.14 61.6 1.75 1.86 47.8 3.09 0.73 83.5 2.89 0.41 78.4 3-96 0.38 86.5 4.19 0.59 86.0 3.93 1.03 83.0

ro

CO

ro oo

cn

Table II Average conditions per trial.

Ta feed

Attempts total lb / h weight

4.2

E to N

° f L to N

10.87

4.73 12.12

8.23 # the one
feeding Pieces lb / h $ the one
feeding sponge 76.1 Total weight
IbA 1.97 18.0 Total weight
lb / h lb / h 0.76 3.16

10.33

85.0

0.67

1.70

power

Attempts KW KW efficiency calc. (gross) (net) # React.-

Temp. 64.2 35.7 55.0 2823

E to N

L to N

ro ο co

63.7

35-9

Table II continued

.vk

OK

56.4 2889

^H 2
Rod, SOFH gas
HpStoich.
Pact. food
carrier 883 15.22 198 (argon) 883 13.6 193 (argon)

CO N) OO

Table III

Analysis according to Fischer

Runs J & K -200 mesh Microns Run M + 200 -100 mesh Microns Porosity setting 1.95 Porosity setting Microns 7.20 .80 1.50 .75 8.4Ό 5.20 ' .75 1.83 .70 6.4-0 3- ³ p5 .70 2.04- .65 6.4-0 2.4-5 .65 1.90 2.55 Mesh Run Ii + 200 -100 mesh 2.35 Microns Porosity setting Microns 50/50 Run L -200 0.90 Qf) 7 '
O Microns Porosity setting 1.10 .75
.70 O
6.8 4-.95 .80 1.30 4-.2 .75 1.4-8 .65 5.9. 3.95 .7.0 1.4-5 .60 5.3 3.05 .65 Mesh Run M + 200 -200 50/50 2ÄO .62 (1.60) Microns Porosity setting 2.bO Run M -200 1.15 .80 -V. 2> Γ-, 0 Porosity setting 1.25 .75 2.60 .80 1.55 .70 2. £ 5 .75 1.51 .65 .70 1.65 .62 .- .65 Mesh .62 .62 Microns Run K +200 -200 Run N -200 Miorono Porosity setting Porosity setting 8.4- .80 Sogooity sotting 1.92 .75 .80 2.?0 .725 .75 2.21 .70 .70 · 2.2 .675 ' .65 .650 .62 .625 .60 r.nc;

209841/0752

The tantalum powder described above was prepared and recovered, "was subjected to analysis to confirm its purity. The results of these Analysis are given in Table IV below in ppm (parts per million).

Table IV Deficiency

Nb

Mon

Fe

Cr

Ni

Mn

Co

Ti

Zr

Cu

Sn

Bi

Pb

Approx

Mg

Al

Si

O ^

Cl C

EES

<Ί0 16

< 3

< 3

<1

<5

<1

<3 ^ 1

< 3

< 1

<1 C.10 1400 1000 1400 1600 110

209841/0752

Experiments were carried out with regard to the electrical properties of capacitor anodes made from thantalum powder according to the invention. A generally accepted criterion for the quality of capacitor anodes is the product of the capacitance and the test voltage per unit weight of the anode material. The Ver-

searches show that the CV product per gram is comparable to the commercially available powders.

Anodes which ^{had been sintered at 190O 0} C gave CV / g values approximately in the range between 2900 to 3360 and with a 2000 ° sintering process from 2400 to 2600. At a sintering temperature of about 1800 °, values of CV / g from about 4000 to 5100 found.

The DC leakage current was 1/4 to 1/2 microamp in Anodes sintered at 2000 °.

When using the device according to FIG. 4, several Trial runs were carried out to determine the efficiency of the process and apparatus in continuous production of elementary, refractory metals. The feed material consisted of columbium pentacloride, which was liquefied with argon carrier gas. The reducing agent consisted of hydrogen.

- 40 -

209841/07 62

After a certain time of the test run, a metallic sponge had formed in the collecting container 152. Of the Container was lowered and the rods T56 pushed inwards, to strip off the formed product when the container 152 has been moved back to its initial position. The formed product fell into the storage container 158. This process was repeated and the touch then completed.

The product formed was subjected to analysis and found to be oolumbium. Of the theoretically possible recoveries were 81.5 # of the columbium in the sponge-like JP pan cake or toro shape (sponge donut shape) while 17 | 8 # of the metal is additional were recovered to give a total recovery of # 99.3. The spectroscopic analysis showed that the Columbium was in a leg shape, as shown in the following Table shows:

Impurities by weight

Si 0.006

Mm in tracks

Fe in traces

Mg in traces

Ca in traces

• Al 0.02

Ou 0.05

209841/0752

Wet analysis

Cl 0.05

O ₂ 0.15

The efficiency of the device and method according to the invention, as well as the range of feasible and applicable chemical reactions were carried out through various experiments which are included in Table V.

Tabel

Effect HpStab. Infeed carrier, feed back- # of the degree in JS -f, «flow SCFH solution gained theoretically yg ' material possible

26 595 V? (ar) WO ₅ 246g 40.7

56.6 883 198 (Ar) (NH ^) ₆ Mo ₇ 2487g

86

66.7 883 198 (Ar) (NH ₄ ) ^ W ₁₂ 4 335g 90.3

O ₄₁ . 5H ₂ O

It can be seen from the previous detailed description, As can be seen from the examples and data, numerous Variations and modifications can be effected without departing from the spirit and scope of the invention. _ 42 _

20Θ8Α1 / 0752

While the recovery of the metallic sponge in Powder form can be converted, is preferred in certain cases, massive metal formation is also possible. Through control prolonged exposure of the metallic sponge to high generated temperatures can result in a metallic product of im substantial solid form can be obtained. These as well as other variations to be realized are obvious to the person skilled in the art,

The in-situ formed elemental metal sponge according to the invention had discrete particles which had a bonding property to form bonded particles to form a porous structure, the elemental particles or powder of a size between 1 and 10 My, which was determined on the basis of gas permeability using the Fisher sub-sieve technique.

The formation of the metallic sponge can be explained by means of the photomicrographs, in particular FIGS. 5 to 8 inclusive.

Fig. 5 (all photomicrographs were taken at a voltage level of 10 kV) depicts the metallic swarm formed at a magnification factor of 1000. The porous nature of the thantalum formed in place is easy to see.

209841/0752

Fig. 6 showing an IFotomicrograph at 5000X "magnification shows, begins to show the worm-shaped figure visibly of formed thantalum.

Figs. 7 and 8, the magnification of which is 10,000 and 20 respectively, clearly show that the tiantalum formed is essentially consists of interconnected particles of the metal, v / in which connection properties are shown, and the overall formation is such as to create a smooth, worm-like (vermicular) property that is opposite to which is usually found in the well-known thantalum powders.

Referring to Figs. 9 to 12 inclusive is an agglomerated Thantal, the present invention is commercially available from the company Fansteel, Inc. and FD-30 ^H type is referred to by this company as ". The difference between the known and the Thantal Thantalum is perfectly clear.

FIGS. 9 to 12 inclusive respectively correspond to FIGS. 5 to δ and are at the same magnification as these pictured.

In this way, the sharp, angled, plate-like formation of the known thantalum is clearly recognized, and this Training completely different from the invention

Is thantalum.

_ / μι. _

2098A1 / 0752

Experiments have been made on the electrical properties of capacitor anodes, which consisted of the thantalum powder produced in the previous experiments. A generally recognized criterion for the quality of capacitor anodes is the product of the capacitance and the test voltage per unit weight of the anode material, the tests show that the CV product / g is comparable to those the commercial powder.

Anodes were sintered at 1900 O, CV / g-values were in the approximate range of 2900 to 3360. In the case of sintered at 2000 ⁰ C anodes of the value was 2400 to 2600 CV / g. At a sintering temperature of approximately 1800 ° C., values of approximately 4000 to 5100 0 · V / g were found.

The DC leakage current was 1/4 to 1/2 micro amps at anodes were sintered at 2000 ⁰ C.

The thantalum according to the invention is therefore not only unique physical properties, but it is also referred to as a refractory or refractory metal powder used, such as in capacitors, and it is recovered in exceptionally pure form without the need the use of the known cleaning procedures, d; j.e are expensive.

- 45 2098A1 / 0752

Obviously, there are other ways of using it of the thantalum of the present invention is obvious to one skilled in the art, and such variations and modifications are considered to be covered by the claims.

- 46 209841/0752

Claims (28)

Expectations 1. A method for the formation of elemental metals using a plasma reactor, characterized in that a) the effluent from the reactor zone into a collection zone of variable differential fluid pressure and temperature is conducted and b) maintaining a selected differential liquid pressure and temperature between the collection zone and the reactor zone and that recovered elementary metals with selected properties are collected. 2. The method according to claim 1, characterized in that Refractory or refractory metals are formed. 3. The method according to claim 2, characterized in that refractory metal compounds are reduced in the reactor zone will. 4 ·. Plasma reactor process for the production of elemental metals, characterized in that a) the reactant is introduced at a point below the anode of the reactor; b) the effluent from the reaction zone is through a variable passage or gap in a 2086 * 17 * 752 directed in a controlled manner to a collection zone and c) the elemental metal is collected while the chosen Control of the effluent flow is maintained. 5. The method according to claim 4, characterized in that maintaining a temperature gradient and pressure differential between the reaction zone and the collection zone. 6. The method according to claim 5, characterized in that the reacting substance is a reducible refractory
Comprises metal compound and that the temperature in the reaction zone is sufficient to carry out the reduction reaction. 7. The method according to claim 6, characterized in that the plasma gas is hydrogen and a plasma jet in the vicinity the place of introduction of the reactive substance forms is. 8 · The method according to claim 7 »characterized in that the pressure difference between the reaction zone and the collecting zone within a range of about 0.5 to 5 pounds / inch lies. 9. The method according to claim 8, characterized in that there is also a Samnelelement in the vicinity of the passage. - 4S - 2098-1 / 0762 is arranged on which the metal forms. 10. The method according to claim 9 »characterized in that the heat-resistant, refractory compound is a halogen is. 11. The method according to claim 10, characterized in that the halogen is thantalum pentachloride and the elemental thereof recovered metal is thantalum in the form of a sponge. 12. Plasma reactor device, characterized by the combination following merlanale: a) the plasma reactor has a cathode and an anode, between which a plasma arc is generated; b) there is a reaction zone element provided with the Communicating with the reactor into which the reactant feed material is introduced below the anode; c) a quenching element is provided which is associated with the reaction zone communicates through which the effluent coming from the reaction zone flows and d) collecting means are provided within the quenching member which have a passage which can be changed as desired or create a gap through which the outflow is directed, • to collect a selected reaction product. - 4.9 - 20984170752 13. Apparatus according to claim 12, characterized in that the reaction zone member is designed to establish a temperature gradient and a pressure differential for the effluent and maintain. Apparatus according to Claim 13, characterized in that the temperature gradient runs through an area of the reaction zone member which is larger in size than the remainder of which is located above the enlarged portions is. 15. Apparatus according to claim 14, characterized in that the enlarged section opens towards the quenching chamber and is essentially in liquid-tight connection therewith stands. 16. Apparatus according to claim I5, characterized in that the quench member is tubular and communicates with an outflow outlet. 17. The device according to claim 16, characterized in that you enlarged portion is bell-shaped and a dependent section of the reaction zone member itself extends in here. 18. Apparatus according to claim 17, characterized in that - 50 - 109841/6752 the collecting elements are approximately cup-shaped and are axially displaceable, essentially over the entire length the quenching element, 19 · Device according to claim 13, characterized in that the reaction zone element, the collecting container and at least the interior of the Absehreekelementes through which the collecting means bewq £> ar, from with respect to the reaction conditions and the formed product consist of inert materials. 20. Apparatus according to claim 19, characterized in that the inert material is tungsten and a plurality of laterally extending elements in the wall of the quenching element are arranged, un to the collected product on the collecting elements to put on. 21 «Elementary, refractory metal in the form of a sponge, characterized in that it consists essentially of interconnected particles of the metal, and a The majority of the particles are larger than 1 My in dimensions, with the largest section of the individual particles being smooth, has a wound or worm-like training in contrast to a sharp, angular training. 22. Metal according to claim 23, characterized in that the interconnected particles of worm - 51 - 209841/0752 like (vermicular) shape. 23 · Metal according to claim 22, characterized in that it by the reduction of a Schwerschmelzliaren metal chloride is obtained. 24. Metal according to claim 23 _1, characterized in that the refractory metal chloride is thantalum pentachloride. 25 · Metal according to claim 24, characterized in that the reduction is carried out in a plasma jet reactor. 26. Metal according to claim 25, characterized in that the sponge is annular. 27. Metal according to claim 26, characterized in that the mead swam relatively free of impurities 28. Metal according to claim 27 »characterized in that it is used as a material for an anode of a capacitor will. 209841/3752