PRODUCTION OF CARBON CRYSTAL STRUCTURE NETWORKS

Abstract

The invention pertains to a process for producing carbon crystal structure networks in a reactor 3 containing a reaction zone 3b and a termination zone 3c, by injecting into the reaction zone 3b a thermodynamically stable microemulsion c, comprising metal catalyst nanoparticles, which is at a temperature above 600°C, preferably above 700°C, more preferably above 900°C, even more preferably above 1000°C, more preferably above 1100°C, preferably up to 3000°C, more preferably up to 2500°C, most preferably up to 2000°C, to produce carbon crystal structure networks e, transferring these networks ea to the termination zone 3c, and rapidly cooling or stopping the formation of carbon crystal structure networks in the termination zone by spraying with water d.

Description

PRODUCTION OF CARBON CRYSTAL STRUCTURE NETWORKS FIELD OF THE INVENTION The invention relates to the manufacture of carbon crystal lattices with improved properties and is directed to new methods for manufacturing such lattices. The invention is particularly relevant to the manufacture of carbon black. BACKGROUND OF THE INVENTION The carbon black industry focuses on providing an allotrope of carbon that differs mainly from graphite and amorphous carbon by its physical arrangement, for use in the manufacture of rubber articles, such as tires, etc., in polygraphy, electronics and cable coatings, in the production of varnishes and paints, which include applications where reinforcing and / or pigmenting properties of carbon black are required. Several different procedures or techniques are known for producing carbon black. Carbon black is primarily produced by partial combustion processes from a carbon-containing gas, such as methane or acetylene. This process is sometimes called the furnace carbon black production process and employs a furnace with a burner or combustion chamber followed by a reactor. The furnace process is typically characterized by low oxygen levels, low densities, short residence times, and high temperatures. As the first step in the furnace carbon black production process, hydrocarbons are atomized at typical temperatures of 1200 to 1900°C, as described in Ullmann's Encyclopedia of Technical Chemistry, Volume 14, pages 637–640 (1977).For this purpose, a zone with high energy density is created by burning a combustible gas or liquid fuel with oxygen or air, and the carbon black feedstock is injected into it. The carbon black feedstock is atomized under these hot combustion conditions; on average, oxygen levels are supplied at a rate of two volumes of carbon black feedstock to approximately one volume of oxygen, in order to ensure that the oxygen is completely consumed in the combustion process. The structure and / or porosity of the final carbon black product can be influenced by the presence of alkali metal or alkaline earth metal ions during carbon black formation, and such additives are therefore frequently added in the form of aqueous solutions, which are sprayed onto the carbon black feedstock agglomerates.The reaction is terminated solely by water injection (rapid cooling), and the carbon black is collected at a temperature of approximately 200–250°C and separated from the waste gas using conventional separators or filters. Due to its low bulk density, the resulting carbon black is then pelletized, for example, in a pelletizing machine with the addition of water, to which small amounts of a pelletizing agent may be added. In chronological order, and to limit the art in furnace carbon black technology, documents US2672402, US4292291, US4636375, W02000 / 032701, and US 2004 / 0248731 provide a description of traditional or conventional carbon black production. Their contents are incorporated herein by reference.It is worth noting that alternative processes also exist, such as lamp black, thermal black, acetylene black, and channel black, all of which are variations of the process described above and ultimately produce a type of carbon black. The most innovative is the plasma carbon black process, which advantageously avoids direct carbon dioxide emissions and reduces fossil fuel consumption. Essentially, these oxygen-poor carbon black manufacturing methods are very similar, except for the different ways they achieve pyrolysis temperature conditions. To date, however, the industry is still struggling to produce carbon black through oxygen-poor reduction processes with parameters comparable to those of carbon black produced through traditional partial combustion. Document GB1514130 (1976) also discloses a method for producing carbon black from liquid hydrocarbons by combustion and partial cracking of the hydrocarbons in a furnace plant. An emulsion of water and a liquid hydrocarbon is introduced into the combustion zone of a furnace, with the aim of using the water to optimize hydrocarbon atomization. The "thermal" atomization of the liquid hydrocarbons, which can only be partially evaporated on their own, is due to the explosive evaporation of the water as the emulsion enters the hot combustion zone. The procedure results in higher carbon black yields and shorter reaction times. The type of emulsion that could be used is not described. No different structures are reported. US patent 3494740 (dated 1970) also discloses the production of carbon black by introducing into the reaction zone of a carbon black furnace an additive comprising a metal selected from the group consisting of nickel, vanadium, iron, cobalt, and mixtures thereof, in an amount within the range of 1 to 80 parts by weight per million parts by weight of the hydrocarbon feedstock to said furnace. The metal may be supplied in water, oil, or emulsion, in order to achieve uniform dispersion in the hydrocarbon feedstock. The properties of the carbon black are listed in Table 1. The type of emulsion that could be used is not described. No different structures are reported. Document US2015 / 064099 relates to methods for the production of carbon black using preheated raw material with scaling control. Water is used for rapid cooling. BRIEF DESCRIPTION OF THE INVENTIONIt has been discovered that the well-established manufacturing procedures of reduction (pyrolysis) or oxidation (combustion) of carbon black can be used to produce networks of carbon crystalline structures that have all kinds of advantageously enhanced electrical, mechanical, and thermal properties, introducing the concept of single-phase emulsification using thermodynamically stable oil-in-water or bicontinuous microemulsions, with metallic catalyst nanoparticles, for the production of conventional (furnace) carbon black.The invention relates to a process for producing crystalline carbon structure networks by providing a thermodynamically stable single-phase emulsion comprising an oil, preferably C14 or higher, more preferably a carbon black feedstock oil, water, and at least one surfactant, and also metal catalyst nanoparticles, and subjecting the emulsion, preferably the emulsified carbon black feedstock, to a carbon black manufacturing process, carbonizing said carbon black feedstock at temperatures above 600°C, preferably above 700°C, more preferably above 900°C, even more preferably above 1000°C, most preferably above 1100°C, preferably up to 3000°C, more preferably up to 2500°C, particularly up to 2000°C. Throughout the text and claims, a single-phase emulsion is a water-in-oil (oil-in-water) microemulsion or a bicontinuous microemulsion comprising metallic catalyst nanoparticles. In a related aspect, the invention pertains to the use of such a single-phase emulsion, preferably an emulsified carbon black feedstock (i.e., a single-phase emulsion comprising carbon black feedstock), for carbonizing the emulsion in a carbon black manufacturing process, preferably a furnace carbon black manufacturing process, thereby obtaining carbon crystalline structure networks. The emulsion is preferably sprayed and atomized in the reactor at the aforementioned elevated temperatures. Again, it was found that the single-phase emulsion should be an oil-in-water or bicontinuous microemulsion comprising metallic catalyst nanoparticles. In the opinion of an expert, the use of water should be minimized, and preferably prohibited, in the reaction section of a traditional carbon black manufacturing process to achieve the desired yields and spherical carbon black structures. Water should only be used to complete the downstream carbon black reaction in the reactor. At best, water is sometimes used as a carrier to spray alkali and alkaline earth metal ions onto the carbon black material. In the final stages of the agglomeration process, the porosity of the carbon black product can be adjusted to meet market requirements. Depending on the source, the carbon black raw material may even be dehydrated before being introduced into the process to increase fuel density and optimize atomization.Given the strong reluctance to use any water—let alone less—during traditional carbon black manufacturing, except for rapid cooling in the final stages, the idea of ​​emulsifying the carbon black feedstock before atomization seems beyond the imagination of most experts. However, modifying conventional carbon black manufacturing by atomizing a stable, single-phase emulsion comprising a carbon black feedstock oil in the reactor has been found to have a dramatic impact. This is because it yields a new crystalline carbon material comprising a network of structures, typically nanofibers, instead of the amorphous carbon black normally obtained from aggregates of spherical particles.The structures of the carbon crystal lattice are so different in morphology that they constitute properties that are different from and even superior to carbon black aggregates, some of which have been exploited later. Without adhering to any single theory, the inventors believe that the orientation and structuring of the surfactant molecules, the oil phase, and the water phase, along with the metal catalyst nanoparticles, give rise to the network formation process that is unique to the new material and the procedure. The metal catalyst nanoparticles were found to be essential. It is believed that the micro- and macrostructures of the emulsions (whether water-in-oil or bicontinuous) act as a precursor / plane for the final carbon network structure, of which the carbon-containing fractions (oil and surfactant phases) will form the fibers and bonds, while the water fraction helps to orient the oil / surfactant phase and the network porosity. The presence of a metal catalyst promotes the carbonization of the carbon components into a fiber structure instead of the spherical orientation typically obtained.A mixture of an immiscible oil and water phase will not produce these structures; that is, without a metallic catalyst present in a thermodynamically stable matrix. Once the emulsion is atomized at high temperatures, the carbonization process instantly “freezes” the carbon fractions into their emulsion structure in the presence of a metallic catalyst, while the water evaporates, leaving a network of (nano)fibers. In this process, the inventors found it crucial to supply the carbon feedstock—oil, such as carbon black—in the form of a single-phase emulsion as described above to the atomization process. The inventors also found that a mere mixture of water and feedstock, or otherwise thermodynamically unstable emulsions, are detrimental to the process and will not produce the carbon crystalline structure networks.Additional evidence is provided below. The inventors also found that single-phase emulsions subjected to atomization and subsequent carbonization should contain metallic nanoparticles that act as catalysts in the formation of these crystalline networks. Increasing the concentration of metallic catalyst nanoparticles further improves performance. It is essential to use bicontinuous or water-in-oil (oil-in-water) microemulsions, in which the emulsions comprise metallic catalyst nanoparticles. These emulsions consist of a continuous oil / surfactant phase, thus forming a network structure. Bicontinuous microemulsions are the most preferred. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1A is a schematic diagram of a continuous furnace carbon black production process according to the present invention comprising, along the axis of the reactor 3, a combustion zone 3a, a reaction zone 3b and a termination zone 3c, producing a hot residual gas stream a1 in the combustion zone by burning a fuel a in a gas b containing oxygen and passing the residual gas a1 from the combustion zone 3a to the reaction zone 3b, spraying (atomizing) a single-phase emulsion c in the reaction zone 3b containing the hot residual gas, carbonizing said emulsion at an increased temperature and rapidly cooling or stopping the reaction in the termination zone 3c by spraying in water d, to obtain networks e of crystalline carbon structure according to the invention; yofrQLn / zznz / e / YiAi yofrQLn / zznz / e / YiAi Figure 1B is a schematic diagram of a semi-batch carbon black production process where a single-phase emulsion c is atomized through a nozzle 4 at the top of reactor 3 in reactor zone 3b at elevated temperatures. This emulsion is carbonized at the elevated temperature in reactor zone 3b, and the resulting carbon crystalline structure e is collected at the bottom of the reactor. Two gas inlets are also present, entering the reactor from the top: one to add inert gas f, preferably nitrogen, to control and / or deplete oxygen levels, and the other to introduce a carbon-containing gas g, preferably acetylene or ethylene, into the reactor. Figs. 2A and 2B are SEM images of networks of carbon black and carbon structures, respectively; Fig. 3 shows an SEM image of carbon crystal structure networks obtained in a bicontinuous microemulsion with 100 mM FeCI3 metal catalyst; Figure 4 shows the modulus of elasticity according to ISO 527 for carbon networks (squares) and glass fibers (circles), which show a mechanical strength for the crystalline networks that is comparable to that of the fibers. Carbon black was found not to contribute reinforcing properties to the composite material; and Fig. 5 shows the bulk resistivity for different compounds (PA6 polyamide; squares; PET: circles) prepared with different loadings of carbon crystal structure lattices prepared using the recipe according to Example 1. DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION 1. A process for producing carbon crystal structure networks in a reactor 3 containing a reaction zone 3b and a termination zone 3c, by injecting a water-in-oil or bicontinuous microemulsion c comprising metal catalyst nanoparticles, into the reaction zone 3b which is at a temperature above 600°C, preferably above 700°C, more preferably above 900°C, even more preferably above 1000°C, more preferably above 1100°C, preferably up to 3000°C, more preferably up to 2500°C, most preferably up to 2000°C, to produce carbon crystal structure networks, transferring these networks to the termination zone 3c, and rapidly cooling or stopping the formation of carbon crystal structure networks in the termination zone by spraying with water d. 2. The process according to embodiment 1, wherein said reactor is a carbon black furnace reactor 3 containing, along the axis of reactor 3, a combustion zone 3a, a reaction zone 3b, and a termination zone 3c, producing a hot residual gas stream a1 in the combustion zone by burning a fuel a in an oxygen-containing gas b and passing the residual gas a1 from the combustion zone 3a to the reaction zone 3b, spraying a water-in-oil or bicontinuous microemulsion c comprising metallic catalyst nanoparticles into the reaction zone 3b containing the hot residual gas, carbonizing said emulsion at a temperature above 600°C, preferably above 700°C, more preferably above 900°C, even more preferably above 1000°C, more preferably above 1100°C, preferably up to 3000°C, more preferably up to 2500°C, most preferably up to 2000°C,and rapidly cooling or stopping the reaction in zone 3c by spraying with water d, to produce networks e of crystalline carbon structure. 3. The process according to any of the above embodiments, wherein the oil phase in the emulsion is aromatic and / or aliphatic, preferably comprising at least 50% by weight of C14 or higher, based on the total weight of the oil phase. 4. The process in accordance with any of the above embodiments, said emulsion comprising at least 1 mM of metallic catalyst nanoparticles, preferably having an average particle size between 1 and 100 nm. 5. A carbon crystal structure network obtainable by the procedure according to any of the above embodiments, wherein said carbon structures are chemically interconnected through a multitude of bonds, including Y and H bonds. yofrQLn / zznz / e / YiAi 6. The network according to embodiment 5, having at least one, preferably at least two, more preferably at least three, most preferably all of the following properties: (i) Iodine adsorption number (IAN) of at least 250 mg / g according to ASTM D1510; (i) Nitrogen surface area (N2SA) of at least 250 m2 / g according to ASTM D6556; (iii) Statistical Thickness Surface Area (STSA) of at least 120 m2 / g in accordance with ASTM D6556; (iv) Oil absorption number (OAN) of at least 150 cc / 100 g in accordance with ASTM D2414. 7. The network according to embodiment 5 or 6, wherein said structures have an average thickness of 1-400 nm, preferably between 5 and 350 nm, more preferably up to 100 nm, in an embodiment between 50 and 100 nm, and / or an average length in the range of 100-10000 nm, preferably 200-5000 nm, more preferably 500-5000 nm; and / or wherein the structures have an average aspect ratio of length to thickness of at least 2. 8. A composite material comprising carbon structure networks according to any of embodiments 5-7, further comprising one or more polymers, for example to add mechanical strength, electrical conductivity or thermal conductivity to said polymer-based composite material, and wherein said networks are in any amount of 1-70% by weight, preferably 10-50% by weight, more preferably between 20-40% by weight, based on the total weight of polymer in the composite material. 9. The composite material according to embodiment 8, exhibiting an E modulus that increases with the lattice concentration measured according to ISO 527. 10. Use of an emulsified carbon black raw material in a carbon black manufacturing process, preferably a furnace carbon black manufacturing process, to produce carbon crystalline structure networks. yofrQLn / zznz / e / YiAi 11. A process for the semi-batch production of carbon crystal structure networks in a reactor 3 where a water-in-oil or bi-batch microemulsion c comprising metallic catalyst nanoparticles is injected from the top of the reactor 3, preferably by spraying using an aerosol inlet 4, to obtain an aerosol, and wherein said networks e are formed at an increased temperature of at least 600°C, preferably 700-1200°C and are deposited at the bottom of the reactor, and wherein the increased temperature is obtained using pyrolysis (e.g., heat source outside the reactor, using oxygen-depleted N2) or combustion (heat source inside the reactor, using air or oxygen). 12. A process for the continuous production of carbon crystal structure networks in a reactor 3 where a water-in-oil or bicontinuous microemulsion c comprising metallic catalyst nanoparticles is injected from the top of the reactor 3, said reactor preferably being a thermal black reactor, preferably by spraying using an aerosol inlet 4, to obtain an aerosol, and in which said networks e are formed at an increased temperature of at least 600°C, preferably 700-1200°C and are deposited at the bottom of the reactor, and in which the increased temperature is obtained using combustion (heat source inside the reactor, using air or oxygen), but in which the emulsion is injected only under pyrolysis conditions. The invention can best be described as a process for manufacturing modified carbon black, wherein a suitable oil, preferably an oil comprising at least 14 carbon atoms (> C14), such as carbon black feedstock oil (CBFS), is supplied to the reaction zone of a carbon black reactor as part of a single-phase emulsion, which is a thermodynamically stable microemulsion comprising metal catalyst nanoparticles. The emulsion is preferably supplied to the reaction zone by spraying, thereby atomizing the emulsion into droplets. While the process can be carried out in batches or semi-batches, the manufacturing process for modified carbon black is advantageously carried out as a continuous process. The single-phase emulsion is a microemulsion comprising metal catalyst nanoparticles.The preferred single-phase emulsion comprises CBFS oil, and may be referred to as emulsified CBFS in the context of the invention. In one embodiment, the invention pertains to a process for producing carbon crystal structure networks according to the invention in a reactor 3 containing a reaction zone 3b and a termination zone 3c, by injecting a single-phase emulsion c, which is a microemulsion comprising metal catalyst nanoparticles, preferably an emulsion comprising CBFS, according to the invention into the reaction zone 3b which is at a temperature above 600°C, preferably above 700°C, more preferably above 900°C, even more preferably above 1000°C, more preferably above 1100°C, preferably up to 3000°C, more preferably up to 2500°C, most preferably up to 2000°C, to produce carbon crystal structure networks e.transferring these networks to the termination zone 3c and rapidly cooling or stopping the formation of carbon crystal structure networks in the termination zone by atomizing water. The single-phase emulsion is preferably atomized in the reaction zone. See Figure 1A. In a preferred embodiment, the invention pertains to a process for producing carbon crystal structure networks according to the invention in a furnace carbon black reactor 3 containing, along the axis of reactor 3, a combustion zone 3a, a reaction zone 3b, and a termination zone 3c, producing a hot residual gas stream a1 in the combustion zone by burning a fuel a in an oxygen-containing gas and passing the residual gas a1 from the combustion zone 3a to the reaction zone 3b, spraying (atomizing) a single-phase emulsion c according to the invention, preferably a microemulsion comprising metal catalyst nanoparticles, preferably an emulsion comprising CBFS, in the reaction zone 3b containing the hot residual gas, carbonizing said emulsion at elevated temperatures (at a temperature above 600°C, preferably above 700°C,more preferably above 900°C, even more preferably above 1000°C, more preferably above 1100°C, preferably up to 3000°C, more preferably up to 2500°C, most preferably up to 2000°C), and rapidly cooling or stopping the reaction (i.e., the formation of carbon crystal lattices) in the water spray termination zone 3c. The reaction zone 3b comprises at least one inlet (preferably a nozzle) for introducing the emulsion, preferably by atomization. Reference is made to Figure 1A. Residence times for the emulsion in the reaction zone of the furnace carbon black reactor can be relatively short, preferably in the range of 1-1000 ms, more preferably 10-100 ms. According to conventional carbon black manufacturing procedures, the oil phase can be aromatic and / or aliphatic, preferably comprising at least 50% by weight of C14 or higher, and more preferably at least 70% by weight of C14 or higher (based on the total weight of the oil). Typical oils that can be used, but are not limited to, obtaining stable emulsions include carbon black fuel oils (CBFS), phenolic oil, anthracene oils, fatty acids (short-, medium-, and long-chain), fatty acid esters, and paraffins. The oil is preferably C14 or higher. In one embodiment, the oil preferably has high aromaticity. Within the field, aromaticity is preferably characterized in terms of the Mine Bureau Correlation Index (BMCI). The oil preferably has a BMCI > 50. In one embodiment, the oil has low aromaticity, preferably a BMCI < 15. Carbon black fuel oil (CBFS) is an economically attractive source of oil in the context of the invention, and is preferably a mixture of heavy hydrocarbons comprising predominantly C14 to C50, the sum of C14–C50 preferably amounting to at least 50% by weight, more preferably at least 70% by weight of the feedstock. Some of the most important feedstocks used to produce carbon black include clarified paste oil (CSO) obtained from the fluid catalytic cracking of gas oils, the residue from the ethylene cracker of the steam cracking of naphtha, and coal tar oils. The presence of paraffins ( <C15) reduce sustancialmente su idoneidad, y se prefiere una mayor aromaticidad. La concentración yofrQLn / zznz / e / YiAi yofrQLn / zznz / e / YiAi de compuestos aromáticos determina la rata a la que se forman los núcleos de carbono.The carbon black raw material preferably has a high BMCI to deliver high performance with minimal heat input, thereby reducing manufacturing costs. In a preferred embodiment, and in accordance with current CBFS specifications, the oil, including oil blends, has a BMCI value greater than 120. While a person skilled in the art will have no difficulty understanding what constitutes a suitable CBFS, it is mentioned only as a guideline that—from a performance perspective—a BMCI value for CBFS is preferably greater than 120, and even more preferably greater than 132. The amount of asphaltenes in the oil is preferably less than 10% by weight, and preferably less than 5.0% by weight of the CBFS weight. The CBFS preferably has a low sulfur content, as sulfur adversely affects product quality, leads to reduced performance, and corrodes equipment. It is preferred that the sulfur content of the oil, according to ASTM D1619, be less than 8.0% by weight, preferably below 4.0% by weight, more preferably less than 2.0% by weight. The emulsion, preferably an emulsion comprising CBFS, is a single-phase emulsion, meaning that the oil phase and water phase appear optically as a miscible mixture, with no physical separation of oil, water, or surfactants visible to the naked eye. The single-phase emulsion may be a macroemulsion or a microemulsion and may be kinetically or thermodynamically stable. The process by which an emulsion breaks down completely (coalescence), i.e., the system separates into bulk oil and water phases, is generally considered to be controlled by four different droplet loss mechanisms: Brownian flocculation, creaming, settling flocculation, and disproportionation. A stable single-phase emulsion in the context of the invention is understood to mean that the emulsion does not exhibit any physical separation visible to the eye, preferably reflected in terms of the emulsion not exhibiting any change in pH of more than 1.0 pH unit and / or the emulsion not exhibiting any change in viscosity of more than 20%, for a period of time exceeding the time required for the production of the carbon network structure. The term "stable" may mean thermodynamically stable or kinetically stable (by adding energy, i.e., through mixing). In practice, a single-phase emulsion is considered stable if no optical decomposition occurs, i.e., a single phase is retained, for a period of at least 1 minute after preparation of the emulsion. Therefore, it is preferred that the emulsion maintain its pH within 1.0 pH units and / or viscosity with less than 20% variation over a period of at least 1 minute, preferably at least 5 minutes, after preparation. While extended stability is preferred for handling purposes, it is noted that the manufacturing process can still benefit from the use of emulsions stable for relatively short periods of 1 minute, preferably 5 minutes: by adding energy (mixing), the emulsion's stability can be prolonged, and in the short term, stability can be extended by using in-line mixing. Although macroemulsions are not thermodynamically stable and will always revert to their original, separate, immiscible oil and water phases, the rate of decomposition can be slow enough to make them kinetically stable during the manufacturing process. Provided a stable, single-phase emulsion is obtained, the amounts of water and oil are not considered limiting, but it is observed that reduced amounts of water (and increased amounts of oil) improve yields. The water content is typically between 5 and 50% by weight of the emulsion, preferably 10–40% by weight, even more preferably up to 30% by weight, and more preferably 10–20% by weight of the emulsion. While higher amounts of water may be considered, this will come at the expense of yield. Not wishing to be limited by any theory, the inventors believe that the water phase is attributed to the shape and morphology of the networks thus obtained. The choice of surfactants is not considered a limiting factor, provided that the combination of oil, water, and surfactants results in a stable microemulsion as defined above. For further guidance for the person skilled in the art, it should be noted that the surfactant can be selected based on the hydrophobicity or hydrophilicity of the system, i.e., the hydrophilic-lipophilic equilibrium (HLB). The HLB of a surfactant is a measure of its hydrophobic or lipophilic nature, determined by calculating values ​​for different regions of the molecule according to the Griffin or Davies method. The appropriate HLB value depends on the type of oil and the amount of oil and water in the emulsion, and can be readily determined by the person skilled in the art based on the retention requirements of a thermodynamically stable single-phase emulsion as defined above.An emulsion comprising more than 50% oil by weight, preferably less than 30% aqueous phase by weight, is found to be best stabilized with a surfactant having an HLB value greater than 7, preferably greater than 8, more preferably greater than 9, and most preferably greater than 10. Conversely, an emulsion with at least 50% oil by weight is best stabilized with a surfactant having an HLB value below 12, preferably below 11, more preferably below 10, most preferably below 9, and particularly below 8. The surfactant is preferably selected for compatibility with the oil phase. If the oil is an emulsion comprising a CBFS with a CBFS, a surfactant with high aromaticity is preferred, while an oil with a low BMCI, such as one characterized by a BMCI <15, is best stabilized using aliphatic surfactants.Surfactants can be cationic, anionic, or nonionic, or a mixture thereof. One or more nonionic surfactants are preferred to increase yields, as no residual ions will remain in the final product. To obtain a clean tail gas stream, the surfactant structure is preferably low in sulfur and nitrogen, ideally sulfur- and nitrogen-free. Non-limiting examples of typical nonionic surfactants that can be used to obtain stable emulsions include commercially available series such as Tween, Span, Hypermer, Pluronic, Emulan, Neodol, Triton Xy, and Tergitol. In the context of the invention, a microemulsion is a dispersion made of water, oil (preferably CBFS), and surfactant(s), which is an optically isotropic and thermodynamically stable single liquid with a dispersed domain diameter ranging approximately from 1 to 500 nm, preferably from 1 to 100 nm, and usually from 10 to 50 nm. In a microemulsion, the dispersed phase domains are either globular (i.e., droplets) or interconnected (to give a bicontinuous microemulsion). In a preferred embodiment, the surfactant tails form a continuous network in the oil phase of a water-in-oil (or bicontinuous) emulsion. The water domains contain a metallic catalyst, preferably having an average particle size between 1 nm and 100 nm. The single-phase emulsion, i.e., an oil-in-water microemulsion or a bi-continuous microemulsion, preferably a bi-continuous microemulsion, further comprises metallic catalyst nanoparticles, preferably having an average particle size between 1 and 100 nm. Experts will find extensive guidance in the field of carbon nanotubes (CNTs) for producing and using such nanoparticles. These metallic nanoparticles are found to improve network formation in terms of both rates and yields, as well as reproducibility. Methods for fabricating suitable metallic nanoparticles can be found in Vinciguerra et al. Growth mechanisms in Chemical vapor deposited carbon nanotubes” Nanotechnology (2003) 14, 655; Perez-Cabero et al. “Growing mechanism of CNTs: a kinetic approach” J. Catal. (2004) 224, 197-205; Gavillet et al. “Microscope mechanisms for the catalyst assisted growth of single-wall carbon nanotubes” Carbon.(2002) 40, 1649-1663 and Amelinckx et al. “A formation mechanism for catalytically grown helix-shaped graphite nanotubes” Science (1994) 265, 635-639, its content on the fabrication of metallic nanoparticles is incorporated here as a reference. Metal catalyst nanoparticles are used in a bicontinuous or oil-in-water microemulsion, preferably a bicontinuous or oil-in-water microemulsion comprising CBFS. In one embodiment, the bicontinuous microemulsion is the most preferred. Advantageously, the uniformity of the metal particles is controlled in said (bicontinuous) microemulsion by mixing a first (bicontinuous) microemulsion in which the aqueous phase contains a metal complex salt that can be reduced to the final metal particles, and a second (bicontinuous) microemulsion in which the aqueous phase contains a reducing agent capable of reducing said metal complex salt; upon mixing, the metal complex is reduced, thus forming metal particles. The controlled environment of the (bicontinuous) emulsion stabilizes the particles against sintering or Ostwald ripening.The size, concentrations, and durability of the catalyst particles are easily controlled. Adjusting the average metal particle size within the specified range is considered routine experimentation, for example, by modifying the molar ratio of metal precursor to reducing agent. An increase in the relative amount of reducing agent produces smaller particles. The metal particles thus obtained are monodisperse, with deviations from the average particle size preferably within 10%, and more preferably within 5%. Furthermore, current technology does not impose restrictions on the actual metal precursor, provided it can be reduced. Non-limiting examples of effective catalyst species include noble metals (Pt, Pd, Au, Ag), iron group elements (Fe, Co, and Ni), Ru, and Cu.Suitable metal complexes are, but are not limited to, (i) platinum precursors such as H2PtCI6; H2PtCI6.xH2O; K2PtCI4; K2PtCI4.xH2O; Pt(NH3)4(NO3)2; Pt(C5H7O2)2, (i) ruthenium precursors such as Ru(NO)(NO3)3; Ru(dip)3CI2 [dip = 4,7-diphenyl-1,10-phenanthroline]; RuCI3, or (iii) palladium precursors such as Pd(NO3)2, or (iv) nickel precursors, such as NiCI2.xH2O; Ni(NO3)2; Ni(NO3)2.xH2O; Ni(CH3COO)2; Ni(CH3COO)2.xH2O; Ni(AOT)2 [AOT = bis(2ethylhexyl)sulfosuccinate]. Suitable non-limiting reducing agents include hydrogen gas, sodium boron hydride, sodium bisulfate, hydrazine or hydrazine hydrate, ethylene glycol, methanol, and ethanol. Citric acid and dodecylamine are also suitable. The type of metal precursor is not an essential part of the invention.The metal in the (bicontinuous) microemulsion particles is preferably selected from the group consisting of Pt, Pd, Au, Ag, Fe, Co, Ni, Ru, and Cu, and mixtures thereof, in order to control the morphology of the resulting carbon network structures. The metal nanoparticles become embedded within these structures, where they are physically bonded. While there is no minimum concentration of metal particles at which these networks form—in fact, the networks are formed using the modified carbon black manufacturing process according to the invention—yields were found to increase with increasing metal particle concentrations.In a preferred embodiment, the active metal concentration is at least 1 mM, preferably at least 5 mM, preferably at least 10 mM, plus a preferred furnace black process, with the emulsion residence times in the reactor typically on the order of 1 hour to 7 days, more preferably 8 hours to 3 days. The single-phase emulsion is as defined above, i.e., a water-in-oil (oil-in-water) microemulsion or a bicontinuous microemulsion comprising metal catalyst nanoparticles. Related to this, the invention also pertains to a process for the continuous production of carbon crystalline structure networks in a reactor 3 where a single-phase emulsion c according to the invention is injected from the top of the reactor 3, said reactor preferably being a thermal black reactor, preferably by spraying using an aerosol inlet 4, to obtain an aerosol, and in which said networks e are formed at an increased temperature of at least 600°C, preferably 700-1200°C and are deposited at the bottom of the reactor, and in which the increased temperature is obtained using combustion (heat source inside the reactor, using air or oxygen), but in which the emulsion is injected only under pyrolysis conditions.In a further embodiment, the continuous 'pyrolysis' process, which includes an initial combustion step, is conveniently operated with a carbon feed gas above its cracking temperature, such as methane, ethane, propane, butane, ethylene, acetylene, and propylene; carbon monoxide; oxygenated hydrocarbons such as methanol; aromatic hydrocarbons such as toluene, benzene, and naphthalene; and mixtures thereof, e.g., carbon monoxide and methane. See Figure 1B. The residence time for the emulsion in the reactor is preferably in the range of 1 to 600 seconds, more preferably 5 to 60 seconds. The single-phase emulsion is as defined above, i.e., a water-in-oil (oil-in-water) microemulsion or a bicontinuous microemulsion comprising metal catalyst nanoparticles. According to the preceding semi-discontinuous and continuous processes of the invention, carbon crystal structure networks (i.e., networks of carbon crystal structures) can be produced. In a related aspect, the invention therefore relates to carbon crystal structure networks obtained by or through the process of the invention. The term "carbon structures" is understood to comprise sp2-based crystalline carbon allotropes, i.e., substances in which one carbon atom is bonded to three neighboring carbon atoms in a hexagonal pattern, including graphene, fullerene, carbon nanofibers, and carbon nanotubes. The method of the invention allows the growth of carbon crystal structure networks formed from carbon structures that are chemically interconnected through a multitude of bonds, including Y and H bonds.In the context of the invention, it is preferably understood that a network comprises at least 3, preferably at least 5, more preferably at least 10, more preferably at least 100, more preferably at least 500 chemically connected nodes. Networks preferably have at least one, preferably at least two, more preferably at least three, most preferably all of the following properties: (i) Iodine adsorption number (IAN) of at least 250 mg / g, more preferably at least 300 mg / g, preferably 300-1000 mg / g, in accordance with ASTM D1510; (ii) Nitrogen surface area (N2SA) of at least 250 m2 / g, more preferably at least 300 m2 / g, preferably 300-1000 m2 / g, in accordance with ASTM D6556; (iii) Statistical Thickness Surface Area (STSA) of at least 120 m2 / g, more preferably at least 150 m2 / g, preferably 150-1000 m2 / g, in accordance with ASTM D6556; (iv) Oil absorption number (OAN) of at least 150 cc / 100 g, preferably 150-500 cc / 100 g in accordance with ASTM D2414, wherein: IAN = Iodine Adsorption Number: the number of grams of iodine adsorbed per kilogram of carbon black under specified conditions as defined in ASTM D1510; N2S A = nitrogen surface area: the total surface area of ​​carbon black calculated from nitrogen adsorption data using BET theory, according to ASTM D6556; / «frQLn / zznz / e / YiAi STSA = statistical thickness surface area: the external surface area of ​​carbon black calculated from nitrogen adsorption data using Boer theory and a carbon black model, in accordance with ASTM D6556; and OAN = Oil Absorption Number: The number of cubic centimeters of dibutyl phthalate (DBP) or paraffin oil absorbed by 100 g of carbon black under specified conditions. The OAN value is proportional to the degree of aggregation of the carbon black structure level, determined in accordance with ASTM D2414. For each of IAN, N2SA (or NSA), STSA, and OAN—all typical parameters for characterizing carbon black materials—the networks exhibit superior properties compared to traditional carbon black. The networks of the invention are preferably characterized by at least one, preferably at least two, and more preferably all of (i), (ii), and (iii), as these are typical ways of characterizing the surface area properties of materials. In one embodiment, the networks exhibit at least one of (i), (ii), and (iii), and furthermore comply with (iv). These network-forming structures can be described as nanofibers, which are solid (i.e., not hollow), preferably having an average diameter or thickness of 1–400 nm, more preferably between 5 and 350 nm, more preferably up to 100 nm, and in one embodiment 50–100 nm, compared to the average particle size of 8–500 nm for spherical carbon black particles. In one embodiment, the average fiber length (i.e., the average distance between two junctions) is preferably in the range of 100–10,000 nm, more preferably 200–5,000 nm, and more preferably 500–5,000 nm, as can be determined, for example, using SEM.Alternatively, the nanofibers or structures can preferably be described in terms of an average fiber length-to-thickness aspect ratio of at least 2, preferably at least 3, more preferably at least 4, and most preferably at least 5; in sharp contrast to the amorphous (physically associated) aggregates formed from spherical particles obtained through conventional carbon black fabrication. The aggregates of the carbon structure networks according to the invention are typically on the order of 0.1–100 microns, preferably 1–50 microns, as observed by Laser Diffraction and Dynamic Light Scattering analysis. The invention also relates to a composite material comprising carbon-structure networks according to the invention, further comprising one or more polymers, for example, to add mechanical strength, electrical conductivity, or thermal conductivity to said polymer-based composite material. The networks can be added in any amount tailored to the desired performance, for example, 1–70% by weight, more preferably 10–50% by weight, and even more preferably 20–40% by weight, based on the total weight of polymer in the composite material. In one aspect, the composite material exhibits a modulus of elasticity dependent on the network concentration (modulus E, i.e., an increase with increasing network concentration), for example, as measured according to ISO 527. EXAMPLES Example 1A. Preparation of the carbon crystal structure network. 100 gallons of raw material were prepared, comprising: a) Carbon black paste oil (CBO or CBFS oil) b) Aqueous phase containing 3500 mM of metal precursor salt (FeCl3) c) Aqueous phase containing a reducing agent (3650 mM citric acid) d) Surfactant (TritonX; HLB 13.4). The exact composition of the microemulsions (a + b + d) and (a + c + d) is detailed below: yofrQLn / zznz / e / YiAi CBO Emulsion Water / FeCh Water / CA TritonX a+b+d 70% 10% 0% 20% a+c+d 70% 0% 10% 20% Both microemulsions (a + b + d) and (a + c + d) were added together and a single-phase microemulsion was obtained by stirring, and this microemulsion was stable for more than one hour, which was longer than the entire duration of the experiment. / «frQLn / zznz / e / YiAi The networks thus obtained had the following characteristics: IAN = 382.5 mg / g, according to ASTM D1510 N2SA = 350 m2 / g (ASTM D6556) STSA = 160.6 m2 / g (ASTM D6556) OAN = 170 cc / 100 g (ASTM D2414). Example 2. Carbon black vs red The carbon networks according to example 1 were compared with conventional carbon black produced using (a). Standard grade carbon black typically has a nitrogen surface area (NSA or N2SA) that ranges up to 150 m2 / g (N100 grade rubber carbon black). The morphology of the carbon networks was evaluated using Scanning Electron Microscopy (SEM). The carbon network building blocks were found to be covalently bonded solid (nano) carbon fibers with average fiber diameters less than 100 nm. In contrast, the carbon black building blocks were nodules in which the graphitic layers were arranged in a spherical shape (8–300 nm diameter). SEM images of the carbon black and carbon network building blocks are shown in Figures 2A and 2B, respectively. The carbon networks were found to be organized into aggregate sizes ranging from 1 to 100 pm, while the carbon black aggregates typically ranged from 85–500 nm. Example 3: Effect of metallic nanoparticles. The concentration of the metal catalyst affected the final reaction yields. Three 20 g bicontinuous microemulsions were prepared from isopropyl palmitate (35 wt%), butanol (11.25 wt%), Tween 80 (33.75 wt%), and water (20 wt%). While the first batch was prepared without metal nanoparticles, two batches incorporated 50 and 200 mM FeCl3 metal nanoparticles (based on citric acid and FeCl3 in a 10:1 ratio). Each emulsion remained stable throughout the experiments. The experiment without metal nanoparticles was performed at least 10 times. / «frQLn / zznz / e / YiAi In each case, the emulsions were introduced into the middle of a quartz tube in a horizontal tube thermal reactor. The reactor was heated to 750°C (3 K / min) under a nitrogen flow of 130 sccm and maintained at this temperature for 90 min. During the first 60 min, the nitrogen gas flow was reduced to 100 sccm, and ethylene gas was added at a flow rate of 100 sccm. During the final 30 min at 750°C, the ethylene was purged from the nitrogen at 130 sccm, and the reactor was cooled. Carbon network structures were only obtained with metallic nanoparticles. No networks were found in any of the ten experiments without metallic nanoparticles. The test performed in the presence of 200 mM FeCl3 showed an increased yield of carbon network structures compared to the results reported with 50 mM FeCl3. An SEM image of the networks obtained with a bicontinuous microemulsion based on isopropylpalmitate (35% wt%), butanol (11.25% wt%), Tween 80 (33.75% wt) and water (20% wt), with 100 mM Fe nanoparticles is shown in Figure 3. Example 4: Graph of modulus E in PA6 The carbon mesh powder, as prepared according to the recipe in Example 1, was compounded in different loadings (10, 20, 30, 40 wt%) in Polyamide 6 (Akulon F223D) using a twin-screw extruder (L / D = 38, D = 25 mm) and compared to glass fiber (Chopvantage 3540) compounded at 10, 20, and 30 wt% loadings under the same conditions. The E-modulus was measured according to ISO 527, and the mixture was dried as molded tension rods. The results are shown in Figure 4 and indicate that the carbon mesh performance is comparable to that of the glass fibers. Carbon black was found not to provide significant reinforcement in the thermoplastic at any concentration. yofrQLn / zznz / e / YiAi Example 5: Electrical conductivity graph PA6 and PET. Volume resistivity was measured in different compounds prepared with a carbon network using the recipe from Example 1, at different fillers in Polyamide 6 (Akulon F223D) and PET (Ramapet N1), using a twin-screw extruder (L / D = 38, D = 25 mm). The results are shown graphically in Figure 5. The percolation curves show good dosage control in the static dissipation range and high conductive yields at high fillers. In contrast, the percolation threshold for carbon black in conductive applications was found at lower fillers, i.e., <20 wt%, and dosage control in the static dissipation range was unsatisfactory. Furthermore, the carbon network compounds did not detach up to 30 wt%, whereas carbon black compounds are known to detach even at low fillers. Example 6: Mechanical resistance It was found that carbon nanofiber networks (low IAN, high crystallinity) obtained by the modified carbon black manufacturing process according to the invention can improve the mechanical properties of thermoplastic (and thermoset) polymer resins. The addition of 10 wt% carbon nanofiber networks to a polypropylene copolymer resulted in a 15% increase in tensile strength (at break) and a 16% increase in modulus of elasticity compared to the pure polymer reference. A Brabender® Plasticorder® blender was used to mix a sufficient quantity of carbon nanofiber networks and polypropylene at 210 °C and 80 rpm. The samples were compression molded and tested with an Instron 3366 10 kN tensile tester at 23 °C and 50% RH. jofrQLn / zznz / e / YiAi 10% CarbonOX / PP Modulus (Young's tensile strength 0.05% 0.25%) Tensile strength at yield (zero slope) Tensile strength at yield (zero slope) Tensile strength at break (automatic load drop) Tensile strength at break (automatic load drop) (MPa) (MPa) (%) (MPa) (%) Average 1459.99 20.05 7.68 19.76 9.80 Standard deviation 149.72 1.13 0.20 1.14 0.91 10.3% 5.6% 2.6% 5.8% 9.3% PP Reference Modulus (Young's Tensile Strength 0.05% 0.25%) Tensile Strength at Yield (Zero Slope) Tensile Strength at Yield (Zero Slope) Tensile Strength at Break (Automatic Load Drop) Tensile Strength at Break (Automatic Load Drop) (MPa) (MPa) (%) (MPa) (%) Average 1258.35 18.95 8.76 17.14 13.54 Standard Deviation 141.14 1.17 0.89 1.37 4.30 11.2% 6.2% 10.2% 8.0% 31.7% Example 7: Production using a plasma reactor. Carbon nanofiber networks were produced using plasma instead of carbon gas combustion. The plasma gas used was nitrogen (N2) at 60 kW with an initial plasma flow rate of 12 Nm3 / h. The argon flow rate was set at 0.6 Nm3 / h. The feedstock (emulsion) flow rate was set at 2.5 kg / h. GC measurements were performed to monitor H2 and the progress of carbon conversion. The injection temperature was set at 1400 °C, and the approximate residence time was 4 seconds. The collected material had a density of 0.13 g / cc and showed the presence of carbon nanofiber networks observed by SEM and TEM (see figures). The average fiber diameter was determined to be 70 nm, while the intermediate length was 5 to 10 times the fiber diameter.

Claims

1. A process for producing crystalline carbon structure networks in a furnace carbon black reactor 3 containing a reaction zone 3b and a termination zone 3c, by injecting a water-in-oil or bi-continuous microemulsion c comprising carbon components in an oil phase, metal catalyst nanoparticles, and water into the reaction zone 3b which is at a temperature above 600 °C, preferably above 700 °C, more preferably above 900 °C, even more preferably above 1000 °C, more preferably above 1100 °C, preferably up to 3000 °C, more preferably up to 2500 °C, much more preferably up to 2000 °C, to produce crystalline carbon structure networks e, transferring these networks ea to the termination zone 3c and interrupting or stopping the formation of crystalline carbon structure networks in the termination zone by water spray d.

2. The process according to claim 1, wherein said reactor is a furnace carbon black reactor 3 containing, along the axis of reactor 3, a combustion zone 3a, a reaction zone 3b, and a termination zone 3c, by producing a hot waste gas stream a1 in the combustion zone by burning a fuel a in a gas b containing oxygen and passing the waste gas a1 from the combustion zone 3a to the reaction zone 3b, spraying a water-in-oil or bicontinuous microemulsion c comprising metal catalyst nanoparticles into the reaction zone 3b containing the hot waste gas, carbonizing said emulsion at a temperature above 600 °C, preferably above 700 °C, more preferably above 900 °C, even more preferably above 1000 °C, more preferably above 1100 °C, preferably up to 3000 °C, more preferably up to 2500 °C °C,much more preferably up to 2000 °C, and interrupting or stopping the reaction in the termination zone 3c yofrQLn / zznz / e / YiAi 28 by spraying in water d, to obtain networks of crystalline carbon structure e., 3. The process according to any one of the preceding claims, wherein the carbon components in the oil phase in the emulsion are aromatic and / or aliphatic, comprising at least 50% by weight of C14 or higher, based on the total weight of the oil phase.

4. The process according to any one of the preceding claims, said emulsion comprising metal catalyst nanoparticles of at least 1 mM, preferably having an average particle size of between 1 and 100 nm.

5. The process according to any one of the preceding claims, said emulsion comprising metal catalyst nanoparticles 10 - 250 mM having an average particle size of between 1 and 100 nm.

6. Crystalline carbon structure networks comprising chemically interconnected carbon nanofibers, wherein the carbon nanofibers are chemically interconnected by chemical bonds through a multitude of junctions, including Y and H junctions, comprising at least 500 chemically connected nodes, wherein the carbon nanofibers have an average fiber length to thickness appearance ratio of at least 2, wherein the carbon nanofibers forming the network are not hollow and have an average diameter or thickness of 50-400 nm and / or an average length in the range of 100-10,000 nm, wherein the carbon structure networks are porous and wherein the networks form aggregates with a size of 0.1-100 micrometers.

7. The networks according to claim 6, obtainable by the process according to any one of claims 1-5. yofrQLn / zznz / e / YiAi yofrQLn / zznz / e / YiAi 8. A composite material comprising carbon structure networks according to claim 6 or 7, further comprising one or more polymers, wherein said networks are in any amount from 1-70% by weight, preferably 10-50% by weight, more preferably between 20-40% by weight, based on the total polymer weight in the composite material, suitable for adding mechanical strength, electrical conductivity or thermal conductivity to said polymer-based composite material.

9. The composite material according to claim 8, exhibiting an E modulus that increases with the concentration of the network measured according to ISO 527.

10. A process for the semi-continuous production of crystalline carbon structure networks in a reactor 3 in which a water-in-oil or bi-continuous microemulsion c comprising metal catalyst nanoparticles is injected from the top of the reactor 3, preferably by spraying using an aerosol inlet 4, to obtain an aerosol, and in which said networks e are formed at an elevated temperature of at least 600 °C, preferably 700 - 1200 °C and are deposited at the bottom of the reactor, and in which the temperature increase is obtained using pyrolysis (e.g., heat source outside the reactor, using N2, oxygen-depleted) or by combustion (heat source inside the reactor, using air or oxygen).

11. A process for the continuous production of crystalline carbon structure networks in a reactor 3 in which a water-in-oil or bicontinuous microemulsion c comprising metal catalyst nanoparticles is injected from the top of the reactor 3, said reactor preferably being a thermal black reactor, preferably by spraying using an aerosol inlet 4, to obtain an aerosol, and in which said networks e are formed at an elevated temperature of at least 600 °C, preferably 700-1200 °C and are deposited at the bottom of the reactor, and in which the temperature increase is obtained using combustion (heat source inside the reactor, using air or oxygen), but in which the emulsion is injected only under pyrolysis conditions 5.

12. A crystalline carbon structure network obtainable by the process according to any one of claims 1-5, 10u11, wherein said carbon structures are chemically interconnected through a multitude of bonds, including Y and H bonds.

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