JP2007505975A - Thermally modified carbon black used for various applications and method for producing the same - Google Patents

Abstract

Electrically heated fluidized bed furnaces are designed to be used in processes for continuously heat treating fine particulate material such as carbon black material. In the heat treatment step, a non-reactive fluidizing gas is continuously introduced at a predetermined speed through a nozzle of the furnace, and an unheated carbon black material is introduced into the furnace at a predetermined speed to form a fluidized bed of carbon black. It is formed by applying a voltage to the electrode to heat the fluidized bed and continuously recovering the heat treated carbon black from the discharge tube. The carbon black recovered from the discharge pipe is graphitized to remove sulfur and PAH, has almost no moisture absorption action, and has high oxidation resistance. The obtained furnace carbon black has a particle size of 7 to 100 nm and an oil absorption of 50 to 300 ml / 100 g. Thermal black has a particle size of 200 to 500 nm and an oil absorption of less than 50 ml / 100 g. Thermally modified carbon blacks are used in a variety of food contact applications, water curable polymer systems, zinc carbon batteries, other electrochemical power sources and other electronic applications, semiconductor wires and cables, and bladder compounds. Improve performance characteristics and improve thermal conductivity and processability.
[Selection] Figure 1

Description

<Inventor>
Ayala, Jorge Armando, Mexican nationality, GA 30144, Kennesaw, Klaredon Trace 2690;
Wang, Wadeong, Chinese nationality, GA 30066, Marietta, Upland Drive 3775;
Edwards, Charles, United States citizenship, GA 30075, Roswell, Woodford Pass 4455;
Hard, Charles Earl. United States citizenship, GA 30188, Woodstock, Maple Creek Chase 219
Ranba, Rakshit, Indian nationality, GA 30101, Acworth, Bladewood Bend 6087
<Description of related applications>
This application is a continuation-in-part of US patent application Ser. No. 10 / 786,690 filed on Feb. 25, 2004, which is a U.S. patent application filed on Sep. 18, 2003. This is a continuation-in-part application of 10/66648.
This application claims priority from US patent application Ser. No. 10 / 786,690, filed Feb. 25, 2004.
This application claims priority to US patent application Ser. No. 10 / 66,048, filed on Sep. 18, 2003.
US patent application Ser. No. 10 / 786,690, filed Feb. 25, 2004, and US application Ser. No. 10 / 666,048, filed Sep. 18, 2003, are hereby incorporated by reference.
<Reference to attached microfish>
Not applicable <Background of the invention>
1. FIELD OF THE INVENTION This invention relates to heat treated carbon black. More specifically, the present invention relates to thermally modified carbon blacks, various uses in contact with food, water-curing polymer systems, zinc-carbon batteries, zinc manganese dioxide. It has excellent properties for alkaline batteries, other electrochemical power and electronic applications, semiconductor wires and cables, provides excellent properties for curable bladder compounds and provides additional uses. Carbon black is produced by a continuous heat treatment process according to the present invention.

<Overall background of the invention>
Traditionally, carbon black materials have numerous uses in all aspects of the economy, and a wide range of marketed products contain carbon black as part of their composition. However, it has been found that it is more advantageous to use carbon black having the characteristics of, for example, a high purity carbon black material depending on the use form. In the past, however, it has been difficult to produce such high purity carbon black in a sufficiently short time to produce sufficient quantities for commercial use and to allow economic continuity. Currently, there are demands for carbon black with improved performance in some industries. Applications in these industries include various applications in contact with food, water-curing polymer systems, zinc-carbon dry cells, zinc manganese dioxide alkaline batteries, other electrochemical power and electronic applications, semiconductor wires and cables. However, it is not limited to these. High-purity carbon black that can be used for these applications is carbon black produced by a continuous heat treatment process according to the present invention described later.

<Applications for contact with food>
Food and Drug Administration (FDA) Regulation 21 CFR 178.3297 states that a polymer (2.5% by weight) in producing, manufacturing, packaging, processing, preparing, processing, packaging, transporting or holding food under all temperature conditions. The use of high-purity furnace black (<500 ppb 22 polycyclic aromatic hydrocarbon (PAH) compound with <5 ppb benzoalphapyrene) as the colorant for the following loading) is permitted. Typical furnace black PAH concentrations are higher than allowed by the FDA regulations. The number of furnace carbon black grades that meet FDA regulations is very limited. However, the morphology provided in these grades is often limited. For these applications, channel black, which is not subject to the FDA regulations, is also used, but it is no longer manufactured in the Western Hemisphere or Western Europe.

In a variety of applications that come in contact with foods having a wide range of forms, it is beneficial to produce a carbon black that has been thermally modified to have the properties necessary to meet all FDA regulations.
For the carbon black forms described herein, the primary particle size and size distribution, and the aggregate size and size distribution are measured by ASTM-D3849.

<Applications of semiconductor wires and cables>
Carbon black is used as a semiconductive shield for insulated power cables. The volume resistivity of these semiconductive materials is generally in the range of 10 ^-1 to 10 ⁸ ohm-cm. These materials typically contain polyolefins, conductive carbon blacks, antioxidants and other additives. The main purpose of these shields is to ensure the long life of primary insulation by preventing the accumulation of static electricity. Longer cable life is preferred, which is achieved through the smoothness of the conductor shield interface. Surface smoothness is realized by using carbon black having a large particle size (small surface area). However, the greater the particle size of the carbon black, the higher the resistance. In order to increase the smoothness of the interface of the semiconductor compound, acetylene carbon black is generally used. However, since this type of black is difficult to manufacture and process, there is a problem that its form is very limited as compared with furnace carbon black.

  The compound has at least the same level of interface smoothness as acetylene carbon black, is easy to process, can provide better conductivity and melt flow properties, and unlike acetylene black, It is advantageous to produce a furnace carbon black that is thermally modified so that a variety of forms can be obtained and has low hygroscopicity, which is a highly desirable property in semiconducting compounds.

<Electrochemical power source>
The term “electrochemical power source” is generally understood to be a device that can generate an electric current as a result of a chemical or electrochemical reaction. Carbonaceous materials are widely used for stationary and portable power sources. There are about 50 commercially viable electrochemical power sources in the world market. Many of them use carbon by design for one or more reasons.

The use of carbonaceous materials can be divided into several main groups described below, which can be referred to in the published literature.
[1] I. Barsukov. Applications for Battery Carbons., Battery Power Products and Technology, v. 4, 9, P.30, 2000.
[2] IV Barsukov, JE Doninger, PL Zaleski. Novel Classification and an Application Overview of Graphitic Products used in Power Sources., Book of Abstracts of the 54th Annual Meeting of the International Society of Electrochemistry, Sao Pedro, Brazil, Abstract # 445 , 8-9 / 2003.
[Carbon additives, which enhance electronic conductivity of battery active materials]: Used in almost all alkaline primary and rechargeable lead acid and lithium primary battery systems in addition to the positive electrode of lithium ion batteries and lithium polymer batteries.
[Graphitic carbon as electrode active material]: Used in lithium ion batteries, lithium ion polymer batteries, and part of metal-free batteries and semi-metal batteries.
[Catalysts of chemical reactions and batteries in batteries and fuel cells]: As an example of applications, there are gas diffusion electrodes of fuel cells in addition to gas diffusion electrodes of battery systems for zinc-air batteries or “hearing aids”.
[Carbon as battery assembly components and "processing aid" additives]: Applications include separator plates for fuel cells, carbon rods for carbon / zinc (for heavy loads) cells, carbon-carbon composite batteries, and super capacitors.
[Application of carbonaceous materials as an ingredient of the coatings used in power sources]: Examples of carbon coating applications include double-layer electronic capacitors, electrochemical ultracapacitors “supercapacitors”, zinc-carbon batteries, lithium ion polymer cathodes and There are anode current collector substrate coatings, lithium ion batteries with electrolyte (foil coating for positive and negative electrodes), zinc air primary and rechargeable batteries, alkaline zinc manganese dioxide primary and rechargeable battery can coatings.

The present invention is applicable to all the applications described above, and can be implemented commercially, and includes portable and stationary power supplies in the development stage.
Some examples regarding the properties of the carbonaceous material required for the power supply are described below.

<Application to zinc-carbon "dry batteries">
Acetylene carbon black is generally used in (zinc-carbon) dry cells, imparts conductivity to the cathode (manganese dioxide), and holds (absorbs) the electrolyte. Thus, acetylene black is an attractive material because it can retain more electrolyte in the cathode mixture. However, significant shearing (structural failure) of the carbon black aggregates (aggregates) must be prevented so that the electrolyte retention capacity does not decrease during the mixing process. The aggregates of acetylene black are large but the structure is weak [D. Linden, Handbook of Batteries and Fuel Cells, 3rd ed., McGraw-Hill Book Co., Inc. New York, NY 1995]. Desirable properties of acetylene black lie in low sulfur, low hygroscopicity, and high electrolyte absorption.

  Therefore, producing a thermally modified carbon black that has all the desirable properties of acetylene black, and has a higher aggregate structural strength and better resistance to thermal oxidation. Is beneficial.

<Alkaline battery system>
Electrochemical primary and secondary alkaline batteries Zn \ KOH \ MnO ₂ are typical examples of power supplies in this category. In these batteries, powdered carbonaceous materials are used for the purpose of improving the conductivity of MnO ₂ (electrolytic manganese dioxide (EMD) or chemical manganese dioxide (CMD)) cathodes. In these batteries, a carbon-containing conductive suspension, also called “can coating”, serves as a processing aid and as a conductive bridge at the interface between the EMD cathode and the positive electrode current collector. used.

Conventional carbon (and / or acetylene) black was discontinued in the mid-1980s at least for the purpose of improving conductivity in many alkaline zinc manganese dioxide batteries. However, some battery manufacturers still use a small amount of carbon (acetylene) black (0.01-8% by weight based on MnO ₂ based electrode) to enhance the discharge current density performance of specific power sources. is doing. However, the application of carbonaceous materials is limited because there is a high possibility of a thermodynamically unstable reaction between carbon (acetylene black) and MnO ₂ . Because the carbon black structure has the properties of graphite, the amount of surface groups (the amount of oxygen that reaches the chemicals on the carbon surface) decreases, the carbon black particle size becomes coarser, and the “spring back” characteristics of the powder are controlled. Is done. Also, mixing MnO ₂ with other carbonaceous materials such as graphite improves the conductivity of the MnO ₂ matrix, so in this electrochemical system carbon black is the only carbonaceous material or It can be used as part of a created blend or composite. It can adapt to the said use by heat-processing carbon black by the method as described below.

<Application to Water Curing Polymer Systems>
When using carbon black as a sealant, one of the most important requirements is a very low moisture absorption or moisture pickup. Sealant manufacturers must dry the carbon black and store it under dry nitrogen to prevent moisture absorption. This increases the number of steps, which leads to high costs. Therefore, it is beneficial to produce a carbon black that has been thermally modified so that moisture absorption is substantially zero, which eliminates the need to perform a carbon black drying process and store under dry conditions. Become.

<Application to curable bladder>
In this application, the use of carbon black modified by heat treatment in the curable bladder compound can extend the life of the bladder (predicted by fatigue properties), compared to conventional curable bladder compounds. Improved heat exchange results.

  Generally, the conventional bladder compound uses N300 series carbon black or a combination of acetylene carbon black and N300 series black. The N300 series black improves the strength of the bladder compound, whereas acetylene black contributes to the improvement of thermal conductivity, which is an important element of the cured bladder.

  In this application, heat-treated black contributes to improved thermal conductivity as compared to acetylene black. Therefore, curable bladder compounds comprising these black and N300 series combinations have better thermal conductivity and longer fatigue life. Black may be used alone or in combination. Examples include, but are not limited to, heat treated black and N300 series carbon black.

<Other application examples of heat treated graphite carbon black>
The heat-treated carbon black according to the present invention can be used alone, but as an alternative to conventional carbon black as part of a mixture with other materials (i.e. artificially created composite) Can also be used as There are many applications, equipment components that depend on electronic resistance (eg microphone components, resistors, strain sensitive, temperature sensitive and current sensitive resistors), oil drilling additives (eg stop loss circulation) In the well and oil drilling market, it may be used alone or in combination with other stop loss additives, including but not limited to graphite, other forms of carbon black, glass beads, etc. But are not limited to these.

<Current furnace treatment process>
An important point in producing sufficiently pure carbon black that can be adapted to the above applications and many other potential applications is that the carbon black is thermally modified by a heat treatment process. High purity carbon black has been produced by batch graphitization methods, but this method took days to weeks to complete the process, so the resulting pure carbon black Was not able to obtain the commercially required quantity at a reasonable price. The heat-treated carbon black can also be used as a component for improving thermal conductivity (for example, a curable bladder compound, a heat transfer fluid, etc.).

  It is known to use an Electro Thermal Fluidized Bed (EFB) furnace for high temperature refining and high temperature chemical synthesis of carbonaceous materials and is described in US Pat. Nos. 4,160,813 and 4,547,430, respectively. ing. These methods use a fluidized bed furnace as shown in U.S. Pat. No. 4,543,240, and the cross section of the fluidized bed portion of the EFB furnace is substantially constant along its height, The gas is introduced into the furnace through a plurality of gas nozzles extending in a generally vertical direction through a dispersion plate at the bottom of the furnace. This type of EFB furnace is commonly referred to as "bubble" EFB furnaces.

  The purification and heat treatment method using a bubble type EFB furnace is effective for particles of about 106 μm (140 mesh). However, the bubble EFB furnace cannot perform well for particles smaller than 75 μm (200 mesh). Further, the bubble-type EFB furnace is not effective for, for example, flaky, acicular or other irregularly shaped particles, and moreover, particles having a wide particle size distribution, particularly from 150 μm (100 mesh) contained in the material. However, it is not effective even when the content of small fine particles is large (greater than 30%).

  Processing and / or synthesis of polydisperse materials using a bubble EFB furnace involves the generation of particles smaller than 106 μm (140 mesh). That is, the particles are circulated by the fluidizing gas outside the effective area of the EFB furnace. As a result, the yield of the processed product is reduced with respect to the raw material. This is especially true when a bubble type EFB furnace is used. In the bubble type EFB furnace, the raw material is introduced into the upper part of the fluidized bed, and the treated particles are discharged from the bottom of the furnace.

In particular, in the case of fine particles smaller than 40 μm (325 mesh) or irregularly shaped particles, it is extremely difficult to make the particles flow uniformly when the fluidizing gas passes through the channel of the bubble type EFB furnace, Or it turned out to be impossible. The reason for this is that, since the surface area of the fine particles is relatively large, the cohesive force (g / inch ² ) between the small particles becomes high, and a stagnant region of fluidized gas is generated at the bottom of the fluidized bed. It is considered.

  These disadvantages are due to the specific hydrodynamics of the bubble EFB furnace. In particular, a gas distribution plate and its plurality of vertically oriented gas nozzles create a number of local circulation zones, each zone formed around a single nozzle or multiple nozzles on the distribution plate, and a mixture of particles and gas An upward flow of particles and a downward flow of particles are generated.

<Summary of the invention>
The present invention provides a novel electrically heated fluidized bed furnace in a method for producing high-purity carbon black. The main body of the furnace has an upper cylindrical portion and a lower cylindrical portion. The diameter is larger than the diameter of the lower cylindrical part. There is a conical portion below the lower cylindrical portion, the conical portion and the lower cylindrical portion form a fluidization zone, and the upper cylindrical portion forms an overhead zone. The furnace is provided with at least one electrode extending through the upper cylindrical portion and the lower cylindrical portion, and a lower end of the conical portion is provided with a discharge pipe for discharging the processed material. In the upper part of the furnace body, a supply pipe for introducing the raw material into the lower cylindrical part and at least one gas exhaust pipe for discharging the fluidized gas are arranged. The conical section is provided with a plurality of nozzles for introducing fluidizing gas into the furnace, the nozzles are arranged in a substantially horizontal plane, and the flow of fluidizing gas introduced through the nozzles intersects, An upward flow is formed at the center of the plate.

  Such an electrically heated fluidized bed furnace is configured to be used in a novel process for continuously heating a fine granular material such as a carbon black material, and the process is non-reactive (non-reactive). reactive) fluidizing gas is continuously introduced at a predetermined speed through the nozzle of the furnace, and the carbon black material is continuously fed into the furnace at a predetermined speed through the supply pipe so that a fluidized bed of untreated carbon black material is formed. And applying a voltage to the electrodes so that the fluidized bed is heated and continuously recovering the treated carbon black from the exhaust pipe. The heat treatment process of the present invention used to thermally modify carbon black is described in US patent application Ser. No. 10 / 666,614, “Method and Apparatus” filed Sep. 18, 2003 and assigned to Superior Graphite Co. For Heat Treatment of Fine Particles In An Electrothermal Fluized Bed furnace ", the entire contents of this patent application are incorporated herein by reference.

  The carbon black recovered from the discharge pipe is substantially free of PAH and sulfur. This carbon black is substantially graphitized, there is almost no moisture absorption by the carbon black, and it shows improved oxidation resistance. The heat-treated carbon black contains almost no metal and ash, and exhibits improved fluidity, increased pH, improved thermal conductivity, and improved elasticity. Furthermore, the obtained furnace carbon black has a particle size of 7 to 100 nm and an oil absorption of 50 to 300 ml / 100 g. On the other hand, thermal black has a particle size of 200 to 500 nm and an oil absorption of 50 ml / 100 g.

  Furthermore, in this continuous processing step, commercially useful amounts of thermally modified furnace carbon black and thermal carbon black within a morphologically sufficient range can be produced. Economic effect in use in applications.

  Thermally modified carbon black is used in various food contact applications, water-curing polymer systems, electrochemical applications such as zinc-carbon batteries, alkaline batteries, other electrochemical power supplies and other electronic applications Curable bladder compounds with improved thermal conductivity and processability, semiconductor wire and cable applications, properties that can provide improved performance in other applications not specifically described here but applicable And having a purity. Carbon black is produced by the continuous heat treatment described above, but could also be produced by other related methods besides those described above.

  The object of the present invention is to provide a method for heat-modifying the characteristics of a fine particulate material such as a carbon black material in the process of an electrically heated fluidized bed furnace. Is sometimes referred to as "heat treatment process".

  It is a further object of the present invention to provide a carbon black that has been thermally modified to meet FDA regulations in a variety of applications in contact with food.

  A further object of the present invention is to use carbon that has been thermally modified to improve the performance characteristics of carbon black in applications of water curable polymer systems such as polyurethane foam, polyurethane acrylate, cyanoacrylate, epoxy and silicone. Is to provide black.

  A further object of the present invention is used in zinc-carbon dry cells and has all the desirable properties of acetylene black or high structure carbon black, as well as high conductivity, stronger structure, controlled elasticity in the electrode matrix. Another object of the present invention is to provide a heat-modified carbon black produced through a heat treatment process so as to have electrolyte absorbability and excellent thermal oxidation resistance.

  A further object of the present invention is to be used for alkaline, lithium ion and other electrochemical power sources, having all the desirable properties of acetylene black or highly structured carbon black, and having high conductivity in electrode (active) matrix, stronger structure. Another object of the present invention is to provide a heat-modified carbon black produced through a heat treatment process so as to have controlled elasticity, electrolyte absorption, and excellent thermal oxidation resistance.

  A further object of the present invention is that it is used for conductivity and has all the desirable properties of acetylene black or highly structured carbon black, as well as high conductivity in the active matrix, stronger aggregate structure, controlled elasticity, excellent Another object of the present invention is to provide a heat-modified carbon black produced through a heat treatment step so as to have a high heat-resistant oxidation property.

  A further object of the present invention is to provide a carbon black produced through a heat treatment process so as to be used for a semiconductor cable, having at least an interface smoothness equivalent to that of acetylene black, workability and conductivity. In addition, while improving the melt flow characteristics, unlike acetylene black, various forms can be produced and the hygroscopicity is low. This low hygroscopicity is a very desirable characteristic for a semiconductor compound.

  A further object of the present invention is to provide high purity carbon black produced through a heat treatment step in an electrically heated fluidized bed furnace. Carbon black is substantially free of PAH and sulfur, is almost graphitized, has a reduced volatile metal content, has almost no moisture absorption by carbon black, and improves the oxidation resistance of carbon black.

  A further object of the present invention is to provide a carbon black which has been heat-treated through a heat treatment step, and is a furnace carbon black having a particle size of 7 to 100 nm and an oil absorption of 50 to 300 ml / 100 g, a particle size of 200 to 500 nm and an oil absorption. Contains less than 50 ml / 100 g of thermal black.

  A further object of the present invention is to provide a furnace carbon having the desired properties depending on the important properties that vary depending on the intended application, for example performance properties such as jetness, viscosity / processing, dispersibility, impact strength. It is to provide black or thermal carbon black.

  It is a further object of the present invention to provide a carbon black that has greater flexibility in form and that can be loaded with more than 40% in a carbon black filled polymer masterbatch. This has not been achieved with previous carbon blacks that meet FDA regulations.

  A further object of the present invention is to provide carbon black that has been heat treated in a heat treatment process, including PureBlack with N330 in a butyl curable bladder compound, which compound has improved thermal conductivity and improved Demonstrated fatigue performance.

  A further object of the present invention is to apply heat-modified carbon black to a curable bladder compound by heat treatment, which has an improved bladder life and improved thermal conductivity compared to conventional curable bladder compounds. Can bring.

  The nature, objects and advantages of the present invention will be understood by the following detailed description. In the accompanying drawings, the same elements are denoted by the same reference numerals.

  The carbon black of the present invention modified by heat is used in various applications in contact with foods, water-curing polymer systems, dry batteries, alkaline batteries, zinc-air batteries, lithium ion batteries, nickel-metal hydride batteries, nickel cadmium batteries. And other electrochemical power sources, other electrochemical applications, having properties and purity that can have excellent properties for semiconductor wires and cables. The carbon black of the present invention can be applied to other uses not described here.

  Before describing various uses of the carbon black of the present invention modified by heat, an electrically heated fluidized bed furnace will be described with reference to FIG. The method of the present invention is performed by passing through the furnace, and the carbon black is thermally modified, resulting in unique qualities in various applications.

  Referring to the drawings, a fountain-type EFB furnace (1) of the present invention is shown. Fountain fluidized beds, also known as spout or jetting fluidized beds, are characterized by the formation of a single strong circulating flow of particles and gases. The mixture flows upward in the middle of the fluidized bed and the particles flow downward along the furnace wall. The central upward high-speed flow carries solid particles together and prevents the formation of fine particles, thereby preventing channel formation. Due to the vertical velocity gradient, sufficient fluidization of all fractions of the polydisperse particulate material is achieved.

Referring to FIG. 1, the furnace has a body shell (10) and is generally made of steel and covered with insulation (14). The furnace body (12) is generally made of graphite. The furnace body has a lower cylindrical portion (16) and an upper cylindrical portion (18), and the upper cylindrical portion (18) is located above the lower cylindrical portion (16), and is located above the central cylindrical portion (16). Has a large diameter. A conical gas distributor (20) is disposed under the central cylindrical portion (16), and the gas distributor (20) includes a plurality of distribution nozzles (22) for distributing fluidized gas. Yes. The nozzle (22) is connected to the plenum (24) to allow fluid to flow, and fluidized gas is introduced from the inlet (26) into the plenum (24). The central angle (alpha) of the conical gas distributor (20) is 30 to 90 degrees, preferably 40 to 60 degrees. In the furnace body (12), the space from the top of the gas distribution nozzle (22) to the upper surface of the lower cylindrical part (16) constitutes a fluidized bed zone (28). The space above the fluidized bed zone is generally coincident with the upper cylindrical section (18) and is known as the above-floor space or freeboard zone (30). In the furnace of the present invention, the working height H _fb of the fluidized bed region (28) is substantially equal to the distance between the nozzle (22) and the upper end portion of the lower cylindrical portion (18). It is desirable that H _fb is 1.5 to 2 times the inner diameter ID _fb of the lower cylindrical portion (16) so that the bubble fluidization region is not formed at the uppermost portion of the fluidized bed zone (28). In order to ensure that all entrained particles are separated from the gas flow and are reliably returned to the fluidized bed space of the furnace, the minimum height of the freeboard area, ie the floor space H _OV.S , is the fluidized bed H _fb. 1.5 times the height is desirable.

  Each of the cylindrical portions (16) and (18) and the conical gas distributor (20) preferably have a circular or elliptical cross section. Other cross-sections (e.g., squares, rectangles, octagons, etc.) can still exhibit the desired hydrodynamic properties, but in practice such shapes are due to thermal expansion in the furnace. It will be infeasible.

An elongated electrode (32) extends from the top (34) through the upper cylindrical part (18) and the lower cylindrical part (16) and into the furnace body (12). The electrode (32) is preferably made of a conductive and heat resistant material such as graphite. If a single electrode is used, it must be placed in the center of the furnace body so that it is collinear with the vertical axis Y. If multiple electrodes are used, the electrodes must be arranged symmetrically around the central axis Y. The lower cylindrical portion (16) includes a second sleeve-type electrode (36) disposed substantially coaxially with respect to the elongated electrode (32). The sleeve type electrode is also preferably made of a conductive and heat resistant material, such as graphite. The electrodes (32) and (36) are connected to both ends of a power source (not shown), and the power source generally supplies 20 to 200 volts between the two electrodes (32) and (36). When an electrode is applied between the electrodes, the fluidized material is rapidly heated by direct electrical resistance based on the formula I ² r for converting electrical energy into heat.

  In order to continuously supply the raw material to the fluidized bed zone (28) of the furnace body (12), a supply pipe (38) is provided. As shown, the supply pipe (38) is arranged vertically and extends downward from the uppermost part (34) of the furnace body (12) through the upper cylindrical part (18), with its outlet at the lower part. Adjacent to the top of the cylindrical part (16) or the wall below it. Therefore, raw materials are introduced from the feed pipe (38) into the fluidized bed. At least the upper surface of the fluidized bed is an area where solid particles circulating in the fluidized bed flow downward. This makes loading the raw material into the fluidized bed easier, so that the untreated particles are less likely to be taken into the overbed (floor) space due to the fluidized gas being taken up by the upward flow and the processing. The mixing of the resulting particles and raw materials is better performed.

  The bottom of the furnace body includes a discharge port (40) through which solid waste is continuously drawn by gravity flow without the use of mechanical devices or moving members. The discharge port (40) hangs down from the conical gas distributor (20), and the inlet to the discharge port (40) substantially coincides with the tip of the conical gas distributor (20).

  Gaseous waste is withdrawn through one or more exhaust pipes or gas exhaust pipes (42) at the top (34) of the furnace body (12). This waste gas can be easily purified and processed to control particles and gaseous contaminants as needed.

  In the present invention, the conical gas distributor (20) includes a plurality of fluidizing gas inlet nozzles (22) (eight illustrated), through which the fluidizing gas is supplied to the furnace body (12). To be introduced. In the method of the present invention, the fluidizing gas is typically nitrogen, argon, or other non-reactive gas. The direction of the nozzle (22) is the direction in which the fluidizing gas is sprayed so that it intersects and a strong and uniform upward flow is formed. It will be appreciated that the rate at which fluidized gas exits the nozzle (fluidized gas velocity) depends on the particle size of the material being fluidized.

  In one embodiment, as best shown in FIG. 3, the nozzles (22) are arranged radially with their respective axes X, and the fluidizing gas passes through the conical gas distributor (20). Released towards the center. As another preferred embodiment, the nozzle (22) has a respective axis X of 10 relative to the tangent of the conical gas distributor (20) at the position of the nozzle, as best shown in FIG. It is arranged to form an angle β (beta) of ˜20 °. By arranging the axis X of the nozzle (22) substantially in the tangential direction of the nozzle circle, rotation of the fluidized bed is brought about and the fluidized bed becomes more stable. Moreover, no matter how the position of the elongated electrode (32) is deviated from the central axis Y, the influence is reduced. For this reason, contact between the fluidized particles and the high-speed conical gas distributor (20) is prevented, so that excessive wear due to friction can be prevented.

The nozzle (22) is connected from the inlet of the gas distributor (20) to the outlet (40) so that the fluidizing gas does not disturb or interrupt the discharge of the particles to be processed from the furnace (10). it is preferably arranged at the position of the H _N. H _N is preferably 0.5 to 0.75 of the overall height H _TC of the conical gas distributor (20), more preferably 0.6 to 0.65H _TC .

  Each nozzle (22) has a ring diameter perpendicular to its X axis, where a free cross-sectional area is defined. The total free cross-sectional area of the nozzle (22) should be 0.15 to 0.5% of the cross-sectional area of the cylindrical part of the fluidized bed, ie the cross-sectional area of the lower cylindrical part (16). The free sectional area of the nozzle (22) is preferably 0.25 to 0.4% of the sectional area of the fluidized bed.

  The method of the present invention for treating particulate material in an EFB furnace will be apparent from the foregoing description. First, untreated particulate material is continuously fed by gravity through the feed pipe (38) to the reaction zone of the EFB furnace (10). The untreated particulate material may comprise a fine, irregularly shaped or polydisperse material. In the experimental example, the polydisperse material includes a material having a particle size as small as 1.7 mm (12 mesh) to 5 μm. In addition, the untreated particles are conductive or semiconductive materials such as carbon black, coke (fluid coke, green flexi-bed coke, delayed coke. coke)) and carbonaceous materials such as graphite. Untreated particulate material is discharged from the feed tube (38) at the top of or immediately inside the flow zone of the particle's downward flow.

  The material discharged from the supply pipe is maintained in a fluidized state in the region of the furnace approximately corresponding to the position of the lower cylindrical part (16), current is sent through the fluidized bed, and the material is generally 2200. It is uniformly heated to a high temperature of ˜2400 ° C.

  The treated particulate material is continuously withdrawn through the discharge tube (40) by gravity action at a rate approximately the same as the rate at which untreated particles are introduced. The speed is such that sufficient time is available for the particulate material to undergo the desired heat treatment in the fluidized bed. In the method of the invention using an EFB furnace, no mechanical equipment or moving parts are required inside the furnace in order to discharge the raw material.

  After being discharged through the tube (40), the treated material is cooled in a cooling chamber (not shown). Gaseous emissions can also be withdrawn through the gas exhaust pipe (42) at the top (34) of the furnace body (12). This gaseous effluent can be easily cleaned and treated according to the level of demand as a contaminant.

  By using the EFB furnace of the present invention and heat treating the fine particles, the test result of the recovery rate of the processed particles is 90 +%, and the recovery rate when using a conventional bubble type EFB furnace (generally, The recovery was significantly improved compared to less than 66%). Furthermore, the critical velocity of fluidization was reduced compared to the bubble EFB furnace speed, and was about 0.30 ft / sec to about 0.25 ft / sec for the EFB furnace of the present invention.

  In the heat treatment process of carbon black, heat treatment is performed within a range of 800 to 3000 ° C. in order to improve performance characteristics. In each of the following applications, after the heat treatment step, the furnace carbon black has a particle size of 7 to 100 nm and an oil absorption of about 50 to 300 ml / 100 g. Thermal black has a particle size of 250-500 nm and an oil absorption of less than 50 ml / 100 g. In each case, when the heat treatment of the carbon black is performed in the above-described continuous heating furnace process, sulfur is substantially removed, the carbon black is graphitized, and the oxidation resistance of the carbon black is improved. The advantages of these altered properties in various applications are described in Table 1, “Carbon black property matrix imparted by thermal modification and effects on various applications”, the details of which are as follows: .

<Heat-modified carbon black and water-curable polymer system>
Table 2 shows moisture absorption data for carbon black without heat treatment and carbon black heat treated by the heat treatment method of the present invention using the furnace (10) of the type described with reference to FIGS. ing. As shown in Table 2, the moisture absorption rate of the four types of carbon blacks without heat treatment and with heat treatment was measured after 1 hour and at equilibrium. As is clear from the results in Table 2, the heat-treated carbon black has a significantly lower moisture absorption rate than the carbon black without heat treatment. For example, thermal black without heat treatment has a water absorption rate of 0.18% after 1 hour, whereas thermal black after heat treatment has a water absorption rate of 0.02% after the same hour. As shown in Table 2, the significant difference in water absorption is that other carbon black samples, CDX-975U (2.41% without heat treatment, 0.17% with heat treatment), N220 (1.48% without heat treatment, It is also observed in N08 (0.6% without heat treatment, 0.02% with heat treatment). The comparison result is shown in “Moisture absorption rate at equilibrium (%)” in Table 2. The carbon black of Table 2 is a carbon black manufactured by Columbian Chemicals Company, both without heat treatment and with heat treatment.

  Metal impurities (salts) in carbon black also promote moisture absorption. Table 3 shows that the metal and ash contents in the carbon black (N220 and N330) are reduced by the heat treatment.

  As described in the Technical Background section, low moisture absorption (low hygroscopicity) provides important advantages in the production of water curable polymer systems, semiconductor wires and cables.

<Heat-modified carbon black and semiconductor wires and cables>
In the background of the invention, it has been described that carbon black is used in semiconductor shields for insulated power cables. Acetylene carbon black is generally used to provide excellent smoothness at the interface of the semiconductor compound. However, this type of black is difficult to manufacture and process compared to furnace carbon black. As described with reference to FIG. 1, a heat-modified furnace carbon black is produced by performing a heat treatment on the carbon black, and the resulting carbon black has an acetylene carbon black having at least an interface smoothness. Is equivalent to that obtained with Furthermore, heat-modified carbon black is easy to process and improves conductivity and melt flow characteristics. Furthermore, heat-modified carbon black can be manufactured in a much wider range than acetylene black and has low moisture absorption characteristics that are highly desirable for semiconductor compounds.

Next, Table 4 “Colloidal characteristics” will be described. Table 4 shows a comparison of three different types of carbon blacks, which are CDX-975U (furnace carbon black used in semiconductor compounds), acetylene black, and about 2000 ° C. based on the above heat treatment method. Heat treated CDX-975U. Comparing various characteristics of three different types of carbon black, the heat-treated black has an iodine value (mg / g) of 98.8, NSA (m ² / g) of 71.9, DBPA (ml / 100 g) Is 156.8, the ion content is 0.01%, the pH is 10.6, and the water content is 0.0. In Table 4, the colloidal properties are very similar when comparing the heat treated carbon black and acetylene black, but the heat treated carbon black can provide a wide variety of forms, so it is more versatile and more desirable.

  Analysis of oil absorption number (OAN) and compressed oil absorption number (COAN) using paraffin oil for four types of very high-structure furnace black and acetylene black did. The results in Table 5 indicate that the structural stability of shawinigan acetylene black is the least. Two samples of heat treated CDX-975U show higher stability than acetylene black. When the stability of the aggregate structure is high, the conductivity and processability of these carbon blacks are improved.

  Next, Table 6 “Moisture absorption (MPU) and melt flow characteristics when containing 30% in 10 Ml LDPE” will be described. The three samples of the same carbon black as described above were compared in terms of MPU characteristics and melt flow index when combined with 30% by weight of 10 Ml LDPE. The heat-treated black had an MPU of 0.17% after 1 hour before compounding, an MPU at equilibrium of 0.27%, an MPU of equilibration of the compound of 0.01%, a melt flow index (g / 10 ml) is 7.0. Comparing these values with the characteristics of the two black samples without heat treatment, it is clear that the characteristics of the heat-treated carbon black are more desirable. The load condition of the melt flow index is 190 ° C. and 10 kilograms.

  Table 7 shows the relationship between volume resistivity and processability for polyethylene containing two types of carbon black, acetylene black and heat-treated CDX-975U. Table 7 is a graph of melt flow (gm / 10 min) against logarithmic volume resistivity (ohm cm), and heat treated carbon black has a much lower volume resistivity (ohm cm) than other carbon blacks. Is shown.

  Next, with respect to CDX 975U, the combustion rate in pure oxygen at 450 to 650 ° C. and in the air was compared using a thermogravimetric method. Table 8 shows the burn rate (weight percent loss per minute). These are estimated from the first derivative of the thermogram. As the combustion rate decreases, the activation energy of combustion increases as a function of heat treatment. The heat treatment of CDX-975U was performed at a temperature of 2000 ° C.

  Samples were first heated to the target combustion temperature, equilibrated in an inert atmosphere for 10 minutes, and then held in pure oxygen or air for 2-4 hours. The activation energy of combustion is calculated from the slope of the Arrhenius plot, and the result is shown in Table 8. The activation energy of the heat treated carbon black sample has been shown to be higher than the control CDX-975U.

<Sulfur related test method>
Method used for measurement of the total sulfur content in the carbon black burns carbon black samples in an oxygen-enriched atmosphere, which all sulfur present those converted into SO _2. The detected SO ₂ is quantified by an infrared detection method. This is described in “ASTM Standards”, Vol. 9.01, Method 1619, part C-94, “Standard Test Methods for Carbon Black-sulphur Content”.

  The sulfur content of carbon black is directly related to the sulfur content of the feedstock. The majority of available feedstocks have relatively high sulfur levels, generally exceeding 2%. Most of the sulfur in carbon black is chemically bonded and not reactive. However, when sulfur is contained even in a small amount, various rubbers and industries are greatly affected.

<Moisture absorption after 1 hour of combined plastic and at equilibrium>
The granular plastic compound was dried in a vacuum oven at 80 + 25 ° C. overnight, cooled and then transferred to a controlled humidity chamber (humidity = 71 + 3%, temperature = 23 + 2 ° C.). Samples were weighed at regular intervals (every 15 minutes for the first hour, every 4 hours for the next 24 hours, and every 24 hours thereafter) to measure the amount of water absorbed by the compound. The measurement time generally exceeds 100 hours. The water absorption amount at the time of equilibration of the compound was determined by graphic processing of data. Absorption of atmospheric moisture after carbon black is combined with plastic adversely affects the properties of the plastic being processed.

<Moisture absorption after 1 hour of carbon black and at equilibrium>
This test method can be applied to carbon black in either powder or bead form. Samples are dried at 100 ± 25 ° C. under vacuum (1 mmHg or less) for at least 4 hours. After removal from the vacuum system, the sample is transferred under vacuum to a glove box with controlled temperature and humidity (humidity = 71 + 3% and temperature = 23 + 2 ° C.). After releasing the vacuum state, the black is immediately transferred to a pre-weighed aluminum dish and the carbon black is measured for gravity. In order to determine the amount of moisture absorbed, the sample is weighed at regular intervals (every 15 minutes for the first hour, every 4 hours for the next 24 hours, and every 24 hours thereafter). The measurement of MPU at the time of carbon black equilibrium is generally performed at regular intervals for one week or longer. The amount of moisture absorbed by black is affected by the physical and chemical properties of carbon black.

<Application of heat-modified carbon black to various applications that come into contact with food>
Carbon black is used quite frequently as a colorant for polymers in the production, manufacture, packaging, processing, preparation, processing, packaging, transporting or holding of food under all temperature conditions. Typical furnace black PAH levels exceed those allowed by FDA regulations. There are only a very limited number of furnace carbon blacks of quality that meet FDA regulations. However, the form in which carbon black having these qualities can be produced is limited. Channel blacks used for such applications are outside the scope of the FDA regulations, but are becoming increasingly difficult to obtain. Furthermore, channel black has very poor processing characteristics. In contrast, the heat-modified carbon black of the present invention has characteristics that can meet all FDA regulations for various applications that come into contact with food, and the PAH level is also within the acceptable range of PDA regulations. Is at a lower level.

  When the carbon black of the present invention is applied to various applications that come into contact with food, in order to meet the FDA standards for those applications, the heat treatment for thermal modification to a predetermined grade of furnace or thermal carbon black is performed continuously. A heat treatment method is used. The advantage of this heat treatment method is the flexibility to use any carbon black, depending on the important properties that vary depending on the intended application, for example, performance properties such as jetness, viscosity / processing, dispersibility, impact strength, etc. ) Can be provided to the user. This freedom of form allows the carbon black filled polymer masterbatch to have more than 40% loadings. This cannot be achieved by the conventional FDA-compliant carbon black. The present invention reveals an effective heat treatment to reduce the PAH (polycyclic aromatic hydrocarbon) content of carbon black to a level that meets FDA standards. The N700 series and CDX-975U listed as examples are products of Colombian Chemicals Corporation.

  The FDA standard chromatographic mass spectrum (GC-MS) method was developed for the analysis of the PAH (polycyclic aromatic hydrocarbon) content of CB in various food contact applications. This method is used to evaluate the ability of special heat treatment techniques to reduce the PAH content of carbon black.

<PAH (polycyclic aromatic hydrocarbon)>
Carbon black is always formed in a hot gas stream with pyrolysis. The pyrolysis of such carbonaceous raw materials results in aromatization (ring formation). In the process of forming carbon black, ring formation results in the condensation of these aromatic rings to form PAH compounds that are retained within the carbon black.

<FDA Food Additive Rules>
High-purity furnace black that conforms to the FDA standard contains 22 types of 500 ppb (parts per billion) or less of a PAH compound (see Table 9) and benzopyrene of 5 ppb or less. The PAH content is measured by gas chromatograph mass spectrometry (GC-MS).

<Food contact test of carbon black>
Heat treatment of CB at high temperatures has a significant effect on the surface properties of CB. The PAH content of heat treated CDX-975U, N700 series and non-heat treated N700 series carbon blacks was determined using the FDA standard GC-MS test method. The results are summarized in Table 10. Competing carbon blacks that meet FDA standards are included for comparison.

It is clear that the PHA impurity of N700 series carbon black is greatly reduced by heat treatment (≈1000 ×). The total content of PAHs and BaP in the N700 series and CDX-975U carbon black is very low and meets FDA food additive application regulations. CDX-975U greatly exceeds the purity (low PAH) of competitive products by heat treatment. The heat treatment temperature of CDX-975U is 2000 ° C.
To further enhance the general applicability of heat treatment for PAH reduction, the results for two additional product grades are shown in Table 11.

<Experimental example of thermally modified carbon black used for electrochemical power source>
Regarding the application of thermally modified carbon black in this field, examples of test results in zinc carbon batteries and alkaline batteries are given. Since there are similarities between the battery system and other battery systems, it is possible to extend the scope of claims to many other battery systems described below.

<Experimental example # 1: Application to zinc-carbon battery>
Carbon black is used for dry batteries (zinc carbon batteries). Carbon black is used for both the positive electrode and the carbon rod in this type of battery system.

  When the present invention is applied to this, in order to improve the performance characteristics of the dry cell, the range of the furnace carbon black is modified with heat by performing heat treatment at 800 to 3000 ° C. using the continuous heat treatment process disclosed herein. To do.

In the report of the battery mockup test results study (performed at the Central Energy Laboratory of SPIC Science Foundation, India), all tests were performed at discharge currents of 25 mA, 50 mA and 100 mA, and the results are shown in Table 12. ing. The composition of the cathode was MnO ₂ (87.5%) + graphite (2%) + carbon sample (10.5%) + ZnCl ₂ (30%).

  The capacity of all samples tested was high when the discharge current was low. However, the trend with respect to the sulfur content is the same, and the sample with a low sulfur content has a better cathode capacity than the use with a high sulfur content.

  In conclusion, as is clear from the above results, carbon black having excellent characteristics can be produced by heat-treating carbon black and modifying the carbon black with heat.

<Experimental example # 2: Use of heat-treated carbon black in an alkaline battery>
In order to investigate the conductivity improvement of carbon black by heat treatment, an electrochemical alkaline battery of Zn / KOH / MnO ₂ was manufactured and tested.

  An alkaline zinc manganese dioxide based electrochemical cell (LR2016 size) was manufactured and tested at the Superior Graphite Company. The structure of the battery and the procedure for manufacturing and testing the battery are as described below.

  The electrochemical device used for the test is typical, as shown in FIG. 5, a standard 2016 coin size battery (diameter 20 mm, height 1.6 mm). The battery's stainless steel housing is available from Hoshen (a Japanese company). FIG. 5 shows an outline of the battery in a partially broken perspective view. The structure of this battery is described, for example, in the literature [D. Linden. “Handbook of Batteries and Fuel Cells.”, McGraw-Hill Book Co., Inc., New York, 1995, P. 10.10].

The battery shown in FIG. 5 has as its main components a stainless steel anode cap (1), a cathode cap (6) and a nylon gasket (7), which show the battery housing. The inside of the cathode cap is sprayed with a can coating (5) containing graphite by an airbrush. This coating is available from, for example, Superior Graphite Company, a product called “Formula 39A”. The cathode (3) consists of the active material EMD. An example of this material is a standard alkaline battery AB, available from Kerr McGee (USA). The report of electrochemical data regarding the amount of EMD in the cathode is either 0.35 g or 0.3 g. Carbon black powder has been added to EMD for the purpose of improving conductivity. The amount of carbon varies depending on the purpose of the test. Here we report data for an EMD / carbon ratio of 20/1. A wet cathode mix (impregnated with 30 wt% or 37 wt% KOH electrolyte) is pressed into the preformed coating (4) and dry cathode cap. The pressure is applied, for example, by a semi-automatic hydraulic press manufactured by Carver, Inc. (USA). For example, a cathode pellet is formed by applying a pressure of about 4210 pounds / cm ² (18.7 kilonewtons / cm ² ) for 30 seconds. The final thickness of the electrode is monitored and controlled as an indicator of electrode density. A two-layer Zr cloth separator (5) available from ZirCar (USA) is placed between the cathode and anode (2). As the separator, a two-layer nonwoven fabric separator can also be used. The separator is impregnated with KOH electrolyte before being loaded into the battery. As the anode (2), zinc powder (product name: Zinc Doralloy 104 <0.036 mm) available from Doral Distribution (Switzerland) was used. The amount used is adjusted to be equal to the amount of EMD of the counter electrode. Similarly, the anode paste is impregnated with KOH electrolyte before the battery is assembled. The battery is sealed using a crimp device from Hoshen Corp. (Japan) available for this type of battery.

  In order to confirm the effect, a maximum of 20 batteries were produced for each. These batteries were discharged using a multi-channel battery cycler, such as a 16-channel model from Arbin Instruments (USA). The current density applied to the battery is specifically described in the “Experimental Example” section.

  Most of the experiments described here describe the performance of conventional carbon black and heat-modified carbon black in alkaline zinc manganese dioxide primary batteries, but the performance improves for other batteries using this material as well. It is considered a thing. This idea is based on research results that there are similarities in the conductivity enhancement mechanism in many other battery systems other than alkaline batteries. In addition, for example, in zinc-air primary batteries for “hearing aids”, Li-ion and Li-ion polymer secondary batteries, industrial nickel-cadmium rechargeable batteries, reserve batteries, electrochemical ultracapacitors, fuel cells, and other power sources, The modified carbon black is considered to act more effectively than conventional graphite.

  FIG. 5A shows the discharge curves of five samples of carbon black, which are as follows.

A sample of thermal carbon black produced by Columbian Chemicals Company and heat treated at 2400 ° C. for 60 minutes (heat treatment cycle was performed by Superior Graphite Company).
-A sample of thermal carbon black produced by Colombian Chemicals Company.
-Furne black used in KY and ARK furnaces of Superior Graphite Company.
-Carbon black sample of Super S manufactured by Erachem Comilog (Belgium).
-Sample of heat treated CDX-975U.
-CDX-975U sample without heat treatment.
These samples are reduced in size by (strongly) brushing through a 200 mesh screen.

  FIG. 5A is a constant current (Galvanostatic) discharge curve of an LR2016 battery containing various carbon blacks and / or heat treated carbon black. For each sample, the curves for the two most typical batteries are shown. As is apparent from the graph of FIG. 5A, it can be seen that the heat-treated thermal black provides a conductivity improvement of 5 times or more compared to the heat-treated black. Thermal black without heat treatment and heat black after heat treatment are plotted in comparison with the furnace black used in the furnaces of KY and ARK. The similarity between thermal black and furnace black without heat treatment will be apparent. After graphitization, the performance of carbon black is improved 5 times. In general, furnace black is known to be more insulative than conductive, so that even if it is heat treated, Super S, a highly structured carbon, CDX-975U without heat treatment and heat treatment. I didn't think it would surpass the CDX-975U.

In the same graph, the battery has a high capacity and has the same performance as expanded graphite (a state-of-the-art conductivity enhancing additive for electrochemical alkaline batteries, GA-17 from Superior Graphite Company). The performance of carbon black Super S (manufactured by Erachem) was compared with that of Columbian Chemical's heat-treated CDX-975U and heat-treated CDX-975U. As shown in FIG. 5A, the battery containing heat treated CDX-975U showed the highest discharge capacity compared to the others. Since CDX-975U without heat treatment has a large surface area (about 170 m ² / g), the average discharge voltage is higher than that of a battery containing heat-treated CDX-975U (surface area is about 68 m ² / g). Is shown. Also, CDX-975U cannot be used because it tends to cause a thermodynamically unstable reaction with MnO ₂ due in part to its large surface area.

<Experimental example # 3: Resistance and springback characteristics when heat-treated but not graphitized carbon black powder is used for energy>
For the carbon black powder before and after graphitization, the surface area, resistances and resiliencies are listed in the following table. These three physical properties are very important in electrochemical applications. The test method is as follows.

  In the “elasticity” (expansion) test, the sample is first compressed between two plugs in a cylindrical mold. The mold assembly is subjected to a load of 690 bar (10000 psi). Measure the height of the assembly when stabilized with this load. Next, when the load is removed, the assembly extends vertically until a stable height is reached. The rate of increase in height relative to the initial height during compression is calculated.

  As shown in the following table, the change in elasticity due to heat treatment is significant. This elasticity is important in the process of mixing the electrode material of the power source.

  In the electrical resistance test, a test piece having a predetermined size and volume was prepared from a sample, and the test piece was put in a non-conductive cylindrical mold and a load was applied by two metal electrodes. One-way resistance between these electrodes was measured using a Kelvin bridge. Resistance was calculated in ohm-inch.

  For batteries and other power sources, higher conductivity (lower resistance) is preferred. As shown in the following table, all of the heat-treated samples are more conductive than those without heat treatment. This is probably due to the high degree of graphitization of the heat-treated material.

Analysis of the results in the above table shows that the surface area of carbon generally decreases with heat treatment. The reduction in surface area is believed to be related to the reduction of active groups on the surface, which normally limits side reactions that occur in electrical and electrochemical applications. In applications where the heat treated carbon black must be made into a slurry, the higher the loading rate, the easier the processing is. By repeating the experiment, carbon black having a surface area of 6 to 70 m ² / g could be produced by heat treatment.

  Further analysis of the results in the above table shows that the conductivity of the heat treated carbon black is improved compared to the feed material. Improved conductivity is the ultimate goal of almost all carbon, including coatings, electrodes, assemblies or other applications. The resistance of carbon black made according to the method of the present invention is less than 0.17 ohm-inch (0.43 ohm-cm), which is believed to be inherent to the heat treated carbon black. To the claims.

  When analyzing the results in the above table, the elasticity value of the heat-treated carbon black is increased, and according to the knowledge of the inventors, within the range of 40 to 200% (42 to 81% in the experimental example of the table). It can be controlled.

<Experimental example # 4: Use of other electrochemical power sources and electrons>
The advantages seen in the above two examples will be extended to many other electrochemical power, electronic and stop-loss fluid applications.

  By utilizing a method of producing heat treated and partially graphitized carbon black as disclosed herein, the resulting product has a wide range of electrochemical and electronic applications, depending on its properties. In particular, it can be used for portable and stationary energy systems having the specifications described below. Shall be referred to as

Thermally improved carbon black can be used extensively in many stationary and portable power sources. Its applications can be divided into six main groups as described below.
1. A carbon black additive that has the effect of improving the conductivity of the battery activator and has been improved by heat.
2. Carbon black that is partially graphitized, improved with heat, and used as an electrode activator.
3. Carbon black that is thermally improved and used as a catalyst for battery chemical and electrochemical reactions.
4). Carbon black that is improved by heat and used as a component of battery assemblies.
5). Carbon black, improved by heat and used as a component of power coatings.
6). Carbon black that is improved by heat and used as a component in electrical resistance dependent applications.

  The above heat-improved carbon black can be used alone in any of the above applications, or it is used in combination with graphite and / or carbon black, and / or other chemicals regardless of the type and amount. You can also. The heat-improved carbon black used for the above applications is processed together with other materials, or laminated or coated on other materials. Thermally improved carbon black may also be applied to applications that are currently not well known.

  Specific application examples are described below.

Examples of carbon black additives having the effect of improving the conductivity of the battery activator and improved by heat are as follows.
Zinc-carbon primary battery; magnesium and aluminum primary battery; alkaline manganese dioxide battery; mercuric oxide battery; silver oxide battery; zinc-air battery (cylindrical shape with bottom); lithium battery (lithium / sulfur dioxide primary battery, lithium / Thionyl chloride primary battery, lithium / oxychloride battery, lithium / manganese dioxide battery (primary and rechargeable), lithium / carbon monofluoride battery), lithium / iron disulfide battery, lithium / copper oxide battery, lithium / oxyphosphoric acid Copper battery, lithium / silver vanadate primary and secondary battery; solid electrolyte battery (Li / LiI (A1203) / metal salt battery, lithium iodide battery; Ag / RbAg415 / Me4Nin, C battery); reserve battery (magnesium / note) Liquid battery, zinc / silver oxide reserve battery, spin-dependent reserve Pond, room temperature Li anode reserve battery, thermal battery); secondary battery (lead / acid battery, iron electrode battery, nickel cadmium battery (industrial, aerospace, consumer (portable sealed NiCd)), portable Sealed Ni-MH batteries, propulsion and industrial Ni-MH batteries, Ni-zinc batteries, Ni hydrogen batteries, silver oxide batteries); rechargeable room temperature Li batteries (lithium / ion batteries, lithium / ion polymer batteries); Rechargeable zinc / alkali / manganese dioxide batteries; high-performance batteries for electric vehicles, hybrid vehicles, and emerging markets (metal-air batteries, zinc bromine batteries, sodium-beta batteries, lithium / iron sulfide batteries), fuel Batteries (all portable and stationary batteries), electrochemical ultracapacitors (supercapacitors), double layer capacitors.

  Examples of carbon blacks that are partially graphitized, modified with heat, and used as electrode activators are as follows. It is used as a part or a single material of the negative electrode activator composition of lithium-ion, lithium-ion polymer battery, metal-free battery and semi-metal battery.

Examples of carbon blacks that are thermally improved and used as catalysts for battery chemical and electrochemical reactions are as follows.
Gas diffusion electrodes for zinc-air primary and rechargeable batteries, gas diffusion layers for all types (portable and stationary) fuel cells, and other power systems (eg, electrochemical sensors).

  Examples of carbon blacks that are thermally improved and used as components of battery assemblies and as “processing aids” are as follows. Current collectors for metal-free and semi-metal batteries, separator plates for fuel cells, carbon rods for zinc / carbon primary batteries, additives for positive / negative electrodes for lithium-ion batteries and lithium-ion polymer batteries, monovalent and divalent Parts of an assembly of a silver oxide battery, a Ni-Cd and Ni-MH battery having a sintered electrode structure, and a carbon-carbon composite battery.

  Examples of carbon blacks that are improved with heat and used as a component of the coating of the power supply are as follows. Double layer electronic capacitor, electrochemical ultracapacitor “supercapacitor” zinc-carbon battery carbon coating; lithium-ion polymer cathode and anode, lithium-ion battery with liquid electrolyte (positive and negative foil coating), zinc— Air primary and rechargeable battery current collector substrate coating; zinc, alkali and manganese dioxide primary and rechargeable battery can coating.

  Examples of carbon black that is improved with heat and used as a component in electrical resistance dependent applications are as follows. Components of microphones, resistors, strain sensitive resistors, temperature sensitive resistors and current sensitive resistors. TV picture tube and "Black Matrix" coating.

  Thermally improved carbon black is used alone or in combination with other stop loss additives in the stop loss circulation well and oil drilling market. Examples of the carbon black herein include graphite, other forms of carbon black, glass beads, and the like, but are not limited thereto.

<Application of heat-treated carbon black to curable bladder>
Tables 13 to 20 show the quality improvement of the carbon black heat-treated by the heat treatment process according to the present invention, and the life and thermal conductivity are improved with respect to the curable bladder compound.

  In general, in this application, the thermal conductivity and lifetime improvement effect of the bladder compound by the heat-treated black is greater than that of the control acetylene black.

  Tables 13 through 20 show a comparison of the properties of the two types of thermally modified carbon blacks with acetylene black (a control black commonly used for cured bladders). Both thermally modified black and acetylene black were used with N330 carbon black.

  Table 13 shows the colloidal properties of the carbon black used for the compounds in Table 14, and the application results are shown in Tables 15-20. Carbon blacks “A” and “B” are thermally modified by heat treatment at a temperature of 2000 ° C.

  Table 14 shows the evaluation of the curable bladder.

  Tables 15 and 16 show that the compounds prepared using heat-modified black are slightly more viscous than the control compound.

  Table 17 shows that the curing properties of the compounds prepared using thermally modified carbon black are approximately equivalent to the control compounds.

  Referring to Table 18, the compound is shown to be well dispersed compared to the control black. Referring to Table 19, the modulus of the compound prepared with heat-modified black is somewhat lower than the control, but this is equivalent to slightly increasing the carbon content and the thermal conductivity. Is further improved.

  Table 20 shows that a compound prepared using heat-modified black has excellent thermal conductivity, and has an advantage of improving the life.

  The examples are given by way of illustration only, and the scope of the invention is defined by the claims.

1 is a vertical sectional view of a fountain-type EFB furnace according to the present invention. It is a top view of the fountain type EFB furnace of FIG. FIG. 3 is a cross-sectional view of a fountain-type EFB furnace taken along line 3-3 in FIG. 1 and shows a fluidized gas distribution nozzle. It is a figure which shows the other structural example of a fluidization gas distribution nozzle. It is sectional drawing of LR2016 battery. It is a galvanic current discharge curve of LR2016 battery.

Table 1 is a table showing a carbon black characteristic matrix imparted by thermal reforming and effects brought about by various uses. Table 2 is a table showing moisture absorption data of carbon black without heat treatment and carbon black subjected to heat treatment. Table 3 is a table showing the metal impurities, ash content and sulfur content of the carbon black without heat treatment and the heat treated carbon black. Table 4 shows the colloidal characteristics of the heat-treated carbon black and acetylene carbon black. Table 5 is a table showing the structural stability of VHS black. Table 6 is a table showing water absorption (MPU) and melt flow characteristics when 30% is contained in 10 Ml LDPE. Table 7 is a table showing the relationship between volume resistivity and processability in polyethylene. Table 8 is a table showing the burning rate and activation energy of 975 U without heat treatment and 975 U with heat treatment. Table 9 is a table showing FDA regulations regarding PAH compounds. Table 10 shows the PAH content (ppb) for competing carbon blacks that meet FDA standards, heat treated CDX-975U, heat treated N700 series carbon black, and control N700 series carbon black. . Table 11 is a table showing the PAH content of N220, N330, heat-treated N220, and heat-treated N330 carbon black samples. Table 12 is a graph showing the maximum discharge capacities at three different discharge rates for samples of carbon black without heat treatment and heat-treated carbon black. Table 13 is a table showing the colloidal characteristics of acetylene black (control) and carbon blacks A and B, N330 modified by heat. Table 14 is a table showing the composition of the curable bladder for compounds containing a control compound and thermally modified carbon black. Table 15 is a table showing processing characteristics for compounds containing a control compound and heat-modified carbon black. Table 16 is a table showing characteristics by capillary rheometer for the compound containing the control compound and the thermally modified carbon black. Table 17 is a table showing the MDR curing characteristics for compounds containing a control compound and thermally modified carbon black. Table 18 is a table showing the dispersion characteristics of the compound containing the reference compound and the heat-modified carbon black by the surface analyzer. Table 19 is a table showing the stress-strain and aging-non-aging characteristics of the control compound and the compound containing heat-modified carbon black. Table 20 is a table showing the performance characteristics of the compound containing the reference compound and the thermally modified carbon black.

Claims (47)

  Thermally modified carbon black produced by a treatment process in a continuous electric heating furnace and having a particle diameter of 7 nm to 500 nm and an oil adsorption amount of 30 to 300 ml / 100 g.   The thermally modified carbon black of claim 1, wherein the carbon black includes thermal black carbon and furnace black. The processing steps are
a. Providing an electric heating furnace having a first portion constituting a fluidizing zone and a second portion constituting an overbed zone and comprising a plurality of nozzles for introducing fluidizing gas;
b. Through the nozzle, introducing a non-reactive fluidized gas, forming an upward flow of the gas in the furnace;
c. Untreated carbon black material is introduced into the furnace at a predetermined rate so that the carbon black forms a fluidized bed,
d. Apply voltage to the electrodes in the furnace to heat the fluidized bed,
e. Continuously recover the treated carbon black from the furnace discharge pipe,
The thermally modified carbon black of claim 1 comprising:   The heat-modified carbon black according to claim 1, wherein the heat-treated carbon black is used for a contact with food.   The heat-modified carbon black according to claim 1, wherein the heat-treated carbon black is used in a water-curable polymer system.   The heat-modified carbon black according to claim 1, wherein the heat-treated carbon black is used in a zinc-carbon dry battery.   The heat-modified carbon black according to claim 1, wherein the heat-treated carbon black is used for semiconductor wires and cables.   The heat-modified carbon black according to claim 1, wherein the heat treatment is performed at 800 to 3000 ° C.   2. Thermal reforming according to claim 1, wherein sulfur is removed by heat treatment, carbon black is graphitized, PAH content is reduced, volatile metal content is reduced, and moisture absorption by carbon black is minimized. Carbon black.   The heat-modified carbon black according to claim 1, wherein the carbon black is contained in an electrode material of an electrochemical power source as a carbonaceous material.   The heat-modified carbon black according to claim 1, wherein the carbon black is used together with other carbonaceous materials and is 0.01 to 8% by weight of the total amount of the carbonaceous materials.   The heat-modified carbon black according to claim 1, wherein the carbon black is contained in the oilfield drilling mud and is 0.01 to 8% by weight of the total amount of the oilfield drilling mud.   The heat-modified carbon black according to claim 1, wherein the carbon black is contained in a coating material for a cathode ray tube of a TV as a carbonaceous material.   The heat-modified carbon black according to claim 1, wherein the carbon black is 0.01% to 99.9% of the total amount of the carbonaceous material of the coating agent for the cathode ray tube of TV.   The heat-modified carbon black according to claim 1, wherein the carbon black is used in a conductive coating agent as a carbonaceous material.   The heat-modified carbon black according to claim 1, wherein the carbon black is 0.01% to 99.9% of the total amount of the carbonaceous material of the conductive coating agent. A heat-modified carbon black having a particle size of 7 nm to 500 nm, an oil adsorption amount of 30 to 300 ml / 100 g, and produced by a treatment process of a continuous electric heating furnace,
a. Providing an electric heating furnace having a first portion constituting a fluidizing zone and a second portion constituting an overbed zone and comprising a plurality of nozzles for introducing fluidizing gas;
b. Through the nozzle, introducing a non-reactive fluidized gas, forming an upward flow of the gas in the furnace;
c. Untreated carbon black material is introduced into the furnace at a predetermined rate so that the carbon black forms a fluidized bed,
d. A voltage is applied to the electrodes in the furnace to heat the fluidized bed to a temperature of 800-3000 ° C.,
e. It includes a process of continuously recovering the carbon black graphitized by the above process from the furnace exhaust pipe, and the carbon black contains almost no sulfur and residual PAH, has minimal hygroscopicity, and has high oxidation resistance. Heat-modified carbon black.   Carbon black used for semiconductor wires and cables, manufactured through a treatment process in a continuous electric heating furnace, having a graphitized particle size of 7 to 500 nm and an oil absorption of about 30 to 300 ml / 100 g The compound prepared from the carbon black is a heat-modified carbon black having excellent interfacial smoothness and conductivity and excellent melt flow characteristics.   Carbon black used for a zinc-carbon battery, manufactured through a treatment process in a continuous electric heating furnace, having a graphitized particle size of 7 to 500 nm and an oil absorption of about 30 to 300 ml / 100 g, Thermally modified carbon black with a stronger structure and better oxidation resistance than acetylene black.   Carbon black for use in contact with food, manufactured through a treatment process in a continuous electric furnace, graphitized particle size of 7 to 500 nm, and oil absorption of about 30 to 300 ml / 100 g Yes, heat-modified carbon black with characteristics that meet FDA standards.   Carbon black used for water-curable polymer, manufactured through a treatment process in a continuous electric heating furnace, having a graphitized particle size of 7 to 500 nm and an oil absorption of about 30 to 300 ml / 100 g Low heat absorption carbon black. Carbon black used for semiconductor wires and cables, having a graphitized particle size of 7 to 500 nm and an oil absorption of about 30 to 300 ml / 100 g,
a. Providing an electric heating furnace having a first portion constituting a fluidizing zone and a second portion constituting an overbed zone, and comprising a plurality of nozzles for introducing a fluidizing gas;
b. Through the nozzle, introducing a non-reactive fluidized gas, forming an upward flow of the gas in the furnace;
c. Untreated carbon black material is introduced into the furnace at a predetermined rate so that the carbon black forms a fluidized bed,
d. A voltage is applied to the electrodes in the furnace to heat the fluidized bed to a temperature of 800-3000 ° C.,
e. Produced by a heat treatment step including a step of continuously recovering the carbon black graphitized by the treatment from the furnace discharge pipe,
Carbon black contains almost no sulfur, has minimal hygroscopicity, and has high oxidation resistance. The compound containing carbon black has excellent interfacial smoothness and conductivity, and has excellent melt flow characteristics. Heat-modified carbon black. Carbon black used for a zinc-carbon dry battery having a graphitized particle size of 7 to 500 nm and an oil absorption of about 30 to 300 ml / 100 g,
a. Providing an electric heating furnace having a first portion constituting a fluidizing zone and a second portion constituting an overbed zone and comprising a plurality of nozzles for introducing fluidizing gas;
b. Through the nozzle, introducing a non-reactive fluidized gas, forming an upward flow of the gas in the furnace;
c. Untreated carbon black material is introduced into the furnace at a predetermined speed to form a fluidized bed of carbon black,
d. A voltage is applied to the electrodes in the furnace to heat the fluidized bed to a temperature of 800-3000 ° C.,
e. Produced by a heat treatment step comprising continuously recovering the carbon black graphitized by the treatment from the discharge pipe of the furnace,
Carbon black is a heat-modified carbon black that contains almost no sulfur, has minimal hygroscopicity, has high oxidation resistance, and is highly conductive. Carbon black used in a water-curable polymer selected from the group comprising polyurethane foam, polyurethane acrylate, cyanoacrylate, epoxy and silicone, having a graphitized particle size of 7 to 500 nm and an oil absorption of about 30 to 300ml / 100g,
a. Providing an electric heating furnace having a first portion constituting a fluidizing zone and a second portion constituting an overbed zone and comprising a plurality of nozzles for introducing fluidizing gas;
b. Through the nozzle, introducing a non-reactive fluidized gas, forming an upward flow of the gas in the furnace;
c. Untreated carbon black material is introduced into the furnace at a predetermined speed to form a fluidized bed of carbon black,
d. A voltage is applied to the electrodes in the furnace to heat the fluidized bed to a temperature of 800-3000 ° C.,
e. Produced by a heat treatment step comprising continuously recovering the carbon black graphitized by the treatment from the discharge pipe of the furnace,
Carbon black is a heat-modified carbon black that contains almost no sulfur, has minimal hygroscopicity, high oxidation resistance, and low hygroscopicity. Carbon black used for applications that come into contact with food, having a graphitized particle size of 7 to 100 nm, an oil absorption of about 30 to 300 ml / 100 g,
a. Providing an electric heating furnace having a first portion constituting a fluidizing zone and a second portion constituting an overbed zone and comprising a plurality of nozzles for introducing fluidizing gas;
b. Through the nozzle, introducing a non-reactive fluidized gas, forming an upward flow of the gas in the furnace;
c. Untreated carbon black material is introduced into the furnace at a predetermined speed to form a fluidized bed of carbon black,
d. A voltage is applied to the electrodes in the furnace to heat the fluidized bed to a temperature of 800-3000 ° C.,
e. Produced by a heat treatment step comprising continuously recovering the carbon black graphitized by the treatment from the discharge pipe of the furnace,
Carbon black is a heat-modified carbon black that contains almost no sulfur, has minimal hygroscopicity, has high oxidation resistance, and has a reduced PAH content. An electrochemical alkaline battery made of Zn / KOH / MnO _{2, wherein the} cathode agent contains carbon black modified by heat.   The heat-modified carbon black is used as an additive for imparting conductivity together with other carbonaceous materials, and the carbon black is 0.01% to 8% by weight of the total amount of the carbonaceous material. Item 26. The alkaline battery according to item 26.   An electrochemical cell that contains heat-modified carbon black in the electrode material.   The heat-modified carbon black is used as an additive for imparting conductivity together with other carbonaceous materials, and the carbon black is 0.01% to 8% by weight of the total amount of the carbonaceous material. Item 28. The electrochemical cell according to Item 28.   29. The electrochemical cell of claim 28, wherein the cell has a conductive coating of carbonaceous material and is 0.01% to 99.9% of the total amount of carbonaceous material.   An assembly or part of an electrochemical cell comprising heat-modified carbon black.   An assembly or part of an electrochemical cell comprising 0.01% to 99.9% by weight of the assembly of thermally modified carbon black.   32. The assembly of claim 31, wherein the assembly is made by a process selected from the group consisting of press molding, molding, compression molding, electrosolidification, hot pressing and hot rolling.   An electrochemical cell comprising heat-modified carbon black, wherein the carbon black is used as an additive as a catalyst for chemical and electrochemical reactions and processes.   An electrochemical cell comprising thermally modified carbon black, wherein the carbon black is used as an additive as a catalyst for chemical and electrochemical reactions and processes, and 0.01% to 99% of the catalyst-containing electrode. An electrochemical cell that is .9%.   An electrical resistance dependent device comprising thermally modified carbon black, wherein the carbon black is used with other powder materials and is comprised between 0.01% and 99.9% by weight of the device apparatus.   Carbon black used in a curable bladder for tire manufacture, having a particle size of 7 nm to 500 nm, an oil adsorption amount of 30 to 300 ml / 100 g, and the curable bladder compound containing the carbon black is a conventional bladder compound Thermally modified carbon black with better thermal conductivity and longer fatigue life.   38. The thermally modified carbon black of claim 37, wherein the carbon black is produced through a processing step in a continuous electric heating furnace.   38. The thermally modified carbon black of claim 37, wherein the thermally modified carbon black is used with furnace black.   38. The thermally modified carbon black of claim 37 used in place of acetylene black and conventional carbon black when used in a curable bladder.   An improved curable bladder compound comprising heat-modified carbon black, the carbon black having a particle size of 7 nm to 500 nm and an oil adsorption amount of 30 to 300 ml / 100 g. A curable bladder compound having better thermal conductivity and longer fatigue life than conventional bladder compounds when black is used with furnace black.   42. The curable bladder compound of claim 41, wherein the bladder compound improves the service life of the curable bladder.   Carbon black used in curable bladders for tire manufacturing, manufactured through a process in a continuous electric heating furnace, and has better thermal conductivity than conventional bladder compounds and has a long fatigue life black.   The heat-modified carbon black according to claim 43, having a particle size of 7 nm to 500 nm and an oil adsorption amount of 30 to 300 ml / 100 g.   A carbon black used in a curable bladder for manufacturing tires, which is manufactured through a processing step in a continuous electric heating furnace, has a particle size of 7 nm to 500 nm, and an oil adsorption amount of 30 to 300 ml / 100 g. Thermally modified carbon black with better thermal conductivity than bladder compounds.   46. The thermally modified carbon black of claim 45, wherein the conventional bladder compound comprises acetylene black.   46. The thermally modified carbon black of claim 45, wherein the carbon black improves the fatigue life of the compound.

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