Methods and systems for nanomaterial production

Abstract

The present invention relates to a method for the combined production of nanomaterials and heat, comprising providing at least one precursor material and a fuel to a combustion device 11 for the production of heat and nanoparticles, thereby combusting the precursor material at a sufficient temperature to decompose and oxidize it. The heat produced in the combustion of the fuel and precursor material is recovered by using at least one heat exchanger 12. The burned fuel is cooled and the nanoparticles produced in the combustion in the form of oxides are collected. The system of the present invention for the combined production of nanomaterials and heat comprises a combustion device 11, means for providing at least one precursor material, a fuel and an oxidizer to the combustion device for combustion, a heat exchanger 12 for recovering heat from the combustion device 11 and cooling the burned fuel, and means 13 for collecting nanomaterials in the form of oxides from the combustion of the precursor material.

Description

[Technical Field]

[0001] The present invention relates to a method and system for nanoparticle production. [Background technology]

[0002] Nanomaterials and / or nanoparticles are sized between 1 and 100 nanometers and are used in a wide range of applications, such as materials manufacturing, energy, and electronics. Most applications require a precisely defined, narrow range of particle sizes (monodisperse).

[0003] Specific synthetic processes are used to produce various nanoparticles in the form of powders, coatings, dispersions, or composites, and well-defined production and reaction conditions are crucial in obtaining such size-dependent particle characteristics.

[0004] Two basic approaches are used to produce nanoparticles, often referred to as "top-down" and "bottom-up" processes. Here, the term "top-down" refers to the mechanical pulverization of raw materials using a milling process. In the "bottom-up" approach, the structure is assembled by chemical processes. The choice of each process depends on the chemical composition and desired characteristics specified for the nanoparticles.

[0005] Bottom-up methods are based on the physicochemical principles of molecular or atomic self-assembly to generate more complex structures from atoms or molecules and provide better control over size, shape, and size range. They include aerosol processes, precipitation reactions, and gas-phase processes also known as sol-gel processes.

[0006] Gas-phase, or aerosol, processes are one of the most common industrial-scale technologies for producing nanomaterials in powder or film form. Such aerosol technologies involve methods in which small particles are produced in the gas phase. In this technology, nanoparticles are tailored in both size and composition by forming the particles in a gas-phase environment.

[0007] Nanoparticles are produced from the gas phase by generating vapors of the product material using chemical or physical means. The production of the initial nanoparticles, which can be in a liquid or solid state, occurs by homogeneous nucleation.

[0008] Depending on the process, further particle growth may involve condensation (transition from a gaseous to a liquid aggregate state), chemical reactions at the particle surface and / or coagulation processes (adhesion of two or more particles), and coalescence processes (particle fusion). Examples of further particle growth processes include processes in flame, plasma, laser, and hot-wall reactors that produce products such as fullerenes and carbon nanotubes.

[0009] In a flame reactor, nanoparticles are formed by decomposition of the parent molecules in a relatively hot flame, for example of ethanol or hydrogen. Flame reactors are currently used, for example, for the industrial-scale production of soot, pigments such as titanium dioxide and silicon dioxide particles.

[0010] Metal oxide nanoparticles have many applications, including advanced anodes and cathodes in lithium-ion batteries.

[0011] Prior art presenting methods for their production is disclosed, for example, in US Patent Application No. 2013 / 0045158A1, US Patent No. 6,902,745, US Patent Application No. 20130273430, and US Patent No. 6,475,673B1.

[0012] The paper by Ting-Feng Yi, Shuang-Yuan Yang and Ying Xie is entitled "Recent advances of Li4Ti5O 12The paper, "Effect of Fuel Rate and Annealing Process of LiFePO4Cathode Material for Li-ion Batteries Synthetized by Flame Spray Pyrolysis Method," was published by Abdul Halim, W. Widiyastuti, Heru Setyawan, Siti Machmudah, Tantular Nurtono, and Sugeng Winardi. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] U.S. Patent Application No. 2013 / 0045158A1 [Patent Document 2] U.S. Patent No. 6,902,745 [Patent Document 3] U.S. Patent Application No. 20130273430 [Patent Document 4] U.S. Patent No. 6,475,673B1 [Non-patent literature]

[0014] [Non-Patent Document 1] Paper by Ting-Feng Yi, Shuang-Yuan Yang and Ying Xie, “Recent advances of Li4Ti5O12 as a promising next generation anode material for high power lithium-ion batteries” [Non-patent document 2] Paper “Effect of Fuel Rate and Annealing Process of LiFePO4 Cathode Material for Li-ion Batteries synthesized by Flame Spray Pyrolysis Method” presented by Abdul Halim, W.Widiyastuti, Heru Setyawan, Siti Machmudah, Tantular Nurtono, and Sugeng Winardi Summary of the Invention

[0015] The method of the present invention for the combined production of nanomaterials and heat includes the steps of supplying at least one precursor material and a fuel to a combustion device for the production of heat and nanoparticles, thereby combusting the precursor material at a sufficient temperature to decompose and oxidize it, recovering the heat produced by the combustion of the fuel and precursor material using at least one heat exchanger, cooling the combusted fuel, and collecting the nanoparticles produced in the form of oxides produced by the combustion.

[0016] The system of the present invention for the combined production of nanomaterials and heat includes a combustion device, means for supplying at least one precursor material, a fuel, and an oxidant to the combustion device for combustion, a heat exchanger for recovering heat from the combustion device and cooling the combusted fuel, and means for collecting nanomaterials in the form of oxides from the combustion of the precursor material.

[0017] Preferred embodiments of the invention have the features of the dependent claims.

[0018] Combustion Process Thus, the production of nanomaterials of the present invention occurs by combustion of gaseous or liquid fuels in a power plant to produce power and heat or heat only. Heat and power are generated in the process of the present invention in a conventional manner in a combustion device, preferably a power plant or heat plant, by means of a heat exchanger.

[0019] Combustion, the scientific term for burning, is a chemical process in which a substance called a fuel reacts rapidly with oxygen, releasing heat through the transfer of energy. The products of the combustion reaction are oxides, and the source of oxygen is called the oxidant.

[0020] During combustion, new chemical substances are generally created from fuel and oxidizer. These substances are called exhaust gases. Most exhaust gases in conventional power plant combustion devices come from the chemical combination of fuel and oxygen. The temperature of the exhaust gases is high due to the heat transferred to the exhaust gases during combustion. Thus, heat is generated during the combustion process as the fuel and oxidizer are converted into exhaust products.

[0021] The key condition is that the precursor solution must break down into small droplets, after which evaporation / precursor decomposition, combustion, nucleation / condensation, aggregation, agglomeration, and powder collection occur.

[0022] Carbon can be used in the process to achieve advantageous properties in the final product prepared, for example, LTO material. As a result of incomplete combustion, a carbon layer is obtained on the nanoparticles, which improves the functionality of Li-ion batteries.

[0023] In summary, three things must be present for combustion to occur: a fuel to be burned, a source of oxygen, and a heat source. A sufficient ignition temperature of the heat source is required to initiate and sustain the combustion process. As a result of combustion, exhaust gases are produced and heat is released. The combustion process can be controlled by the amount of available fuel, the amount of available oxygen, or the heat source.

[0024] Combustion equipment Combustion devices are commonly used to generate and transfer heat. The heat output of combustion devices can vary widely.

[0025] As used herein, combustion devices are meant to include all types of devices for the generation and transfer of heat only as well as all types of devices for the generation of both heat and electricity.

[0026] The combustion plants used in the invention are in particular industrial power plants, also called power plants, for the generation of heat and power (or electricity) or industrial heat plants for the generation of heat only.

[0027] For example, a steam turbine can be used to convert heat directly into electrical energy.

[0028] One useful power plant for use in this invention is a combined heat and power (CHP) plant that generates electricity and captures otherwise wasted heat to provide useful thermal energy such as steam or hot water that can be used for space heating, cooling, domestic hot water, and various industrial processes. Combined heat and power (CHP) production is the most efficient form of fuel-based energy production.

[0029] Most traditional power plants burn fuel to release energy as heat. In cogeneration production, the energy content of the fuel is recovered, and the portion of the fuel's energy that cannot be converted into electricity is recovered as heat.

[0030] Most power plants around the world burn fossil fuels such as coal, oil, and natural gas to generate electricity and heat. Clean energy sources include nuclear power and increasingly renewable energy sources such as solar, wind, wave, geothermal, and hydroelectric power. Biomass-fired cogeneration plants offer an alternative to environmentally harmful fossil fuels or temporary renewable energy sources.

[0031] Power plants that produce both heat and power are usually based on steam superheating, where a heat recovery steam generator in the form of a boiler operates as an energy recovery heat exchanger to recover heat from a hot gas stream, such as a combustion or other exhaust gas stream, which produces steam that can be used for a process or to drive a steam turbine.

[0032] If the process is to produce power only with a condensing steam turbine, a heat exchanger from the steam turbine uses cooling water to condense the steam into water. If steam is needed for an industrial process, an extraction turbine is used. In a cogeneration plant, the waste heat produced by the plant is used in industrial processes to supplement the heat needs of individual buildings or is exported to a district heating system.

[0033] A combustion system includes a burner within a boiler. The boiler burner burns gas or liquid fuel in a controlled manner within the boiler. The burner is therefore part of the combustion system, usually in the form of a fuel-burning or heat-producing device such as a boiler furnace or stove, where a flame or heat is produced.

[0034] The combustion temperature used must be sufficient to cause decomposition of the precursor material and can vary depending on the precursor material, fuel, their amounts and other reaction conditions, such as flow rate.

[0035] precursor material In some embodiments of the present invention, the at least one precursor material is mixed and dissolved in fuel in one or more separate containers before being fed into a combustion device, where the metal precursor material is dissolved in a liquid fuel, such as ethanol or methanol, and directly combusted in the combustion device to produce heat and power and nanomaterials.

[0036] In another embodiment, the at least one precursor material and fuel are fed separately to a combustion device, and the at least one precursor material is fed by spraying in the form of droplets of an aqueous solution of the precursor material, in which case the precursor materials can be injected separately as solid particles or liquid droplets into a gas burner flame, such as a hydrogen or methane flame, where they decompose at high temperature and form nanoparticles as the flame cools.

[0037] Examples of suitable metal precursors are sulfates, chlorides, nitrates, carbonates, and hydroxides of lithium (Li), titanium (Ti), nickel (Ni), manganese (Mn), cobalt (Co), aluminum (Al), iron (Fe), phosphorus (P), silver (Ag), silicon (Si), carbon (C), niobium (Nb), zinc (Zn), and sulfur (S). Additionally, titanium tetraisopropoxide (TTIP) is a useful organometallic precursor for titanium metal oxide nanoparticles. TiCl4 is an example of a gaseous precursor with a low vaporization temperature.

[0038] Typical Li-ion battery cathode (in LTO-, NMC-, LMO-, or LFP-based batteries) and anode (in LTO-based batteries) precursors contain Li and other elements in inorganic forms, which are much cheaper than organometallic precursors. Lithium and other metals are typically in the form of nitrates, hydroxides, carbonates, sulfates, chlorides, etc. However, chlorides are undesirable due to their corrosive effect in boilers.

[0039] The precursors and fuels used in the method for nanoparticle production are selected to be suitable for both nanoparticle and energy production, particularly with regard to reactivity and solubility, while also taking into account safety and cost.

[0040] Nanoparticle Products The primary goal of the present invention is to produce nanoparticles of metal oxides, such as various lithium oxides, for use in battery electrodes. Examples of metal oxide nanoparticles to be produced include: Li4Ti5O is an anode material for lithium-ion batteries. 12 Lithium-titanium oxide (Li2TiO3 or Li4Ti5O) for production from lithium ion batteries and for production of cathode material Li2TiO3 for lithium ion batteries 12Lithium-titanate-oxide (LTO) can be used with an aqueous binder and a conducting agent in the cathode of some lithium-ion batteries. Lithium-titanate-oxide (LTO) batteries are a type of rechargeable battery. Li4Ti5O 12 The formation of is sensitive to the molar ratio of lithium to titanium in the precursor. Preferably, a stoichiometric ratio of Li / Ti (4:5) should be used. Excess lithium or titanium results in the appearance of a second phase of rutile (TiO2) or ordered Li2TiO3, respectively. The reaction is complete in a short time at high temperatures, i.e., >800°C. - Lithium nickel manganese cobalt oxides. These have the general formula LiNi x Mn y Co z O2 (e.g., LiNiMnCoO2, abbreviated as Li-NMC, LNMC, NMC, or NCM), which are mixed metal oxides for producing cathode materials for lithium-ion batteries. - Lithium iron phosphate (lithium ferrophosphate, LiFePO4, LFP) for producing cathode material for lithium iron phosphate batteries - Lithium Manganese Oxide (LMO, chemical formulas e.g. LiMn2O4, Li2MnO3, LiMnO2, and Li2MnO2 and various composites) for producing cathode materials for lithium-ion manganese oxide batteries (LMO) Normally, one should use the stoichiometric metal ratio for all these other oxides, such as NMC622, which has a Ni / Mn / Co ratio of 6 / 2 / 2. Several different levels of nickel in NMC are of commercial interest. The ratio between the three metals is indicated by three numbers: LiNi 0.6 Mn 0.2 Co 0.2 O2 is abbreviated as NMC622.

[0041] In particular, the nanomaterials produced by the present invention are intended for use in lithium ion batteries, especially lithium titanate oxide (LTO) batteries.

[0042] fuel Fuels can be solid, liquid, or gaseous, but the fuels of this invention are typically liquid or gaseous. Examples of suitable liquid fuels are ethanol, methanol, propanol, or any alcohol in which the precursor materials can be dissolved that does not contain impurities that will affect the quality of the final product. Examples of suitable gaseous fuels are hydrogen or methane or other gaseous fuels such as natural gas, liquefied natural gas (LNG), acetylene, and propane.

[0043] When using a liquid fuel, the metal oxide precursor can be one that dissolves in the fuel. In the case of a gaseous fuel, the precursor can consist of solid particles or liquid droplets that decompose and react in the high-temperature flame to form metal oxide nanoparticles. The combustion temperature depends on various factors, such as the reaction time and rate, the material's in-system delay, and the material itself, but the required temperature is usually within the range of 1000°C to 2500°C.

[0044] oxidizing agent Similarly, the oxidant can be a solid, liquid, or gas, and is preferably air in this invention, or an oxygen-enriched gas or air, or pure oxygen gas O2.

[0045] Nanomaterials Collection The nanoparticles produced are in the form of agglomerates, i.e. nanomaterials in the form of small primary particles of 1-50 nm in size that have stuck together to form agglomerates (preferably not sintered, in which case they are called aggregates).

[0046] The produced nanoparticles are collected as a powder by conventional power plant flue gas cleaning systems such as electrostatic precipitators (ESPs) or bag filters after a heat exchanger where heat is recovered and the flue gas is cooled to a temperature suitable for the flue gas cleaning system (preferably below 200°C). Alternatively, other filtering devices or cyclones or scrubbers can be used for collection.

[0047] advantage The innovation is a technology for complex large-scale nanomaterial production and energy production. In the method, nanoparticles are produced in a combustion process where fuel impregnated with precursor materials is burned in a primarily continuous process. In the process, heat exchangers are used as heat sinks for energy production, similar to existing heat and power plants.

[0048] Traditionally, when liquid fuels are used to produce energy, i.e., heat and electricity, in power plants, the liquid fossil fuels typically used are heavy fuel oil and light fuel oil. These fuels are based on fossil fuels, have a high carbon footprint, and contain impurities such as sulfur and metals. Therefore, these fuels are not suitable for producing very high-purity materials. In contrast, bioethanol and methanol have a low carbon footprint and do not contain harmful impurities, making them suitable for producing high-purity nanomaterials.

[0049] In the present invention, the fuels contemplated are preferably renewable, low carbon footprint sources such as ethanol or methanol produced from biomass feedstocks and green hydrogen produced, for example, by wind energy. In general, green hydrogen is hydrogen fuel produced using renewable energy instead of fossil fuels. It has the potential to provide clean power for manufacturing, transportation, etc., and its only by-product or waste gas is water.

[0050] Conventional production of LTO particles involves synthesis methods that focus on the quality, utility and properties of the end product for their application as anode or cathode materials in Li-ion batteries.

[0051] The method of the present invention is innovative and has the advantage of achieving significant heat recovery. The method of the present invention simultaneously produces nanoparticles and energy that is part of conventional power and heat plants on an industrial scale. In this way, large amounts of nanoparticles can be produced.

[0052] A further aspect and advantage of the present invention is that the heat exchange used simultaneously provides heat and cools the exhaust gas, allowing the nanoparticles to be collected by conventional filter bags and electrostatic filters typically used in power plants. In practice, the exhaust gas is already cooled before conventional filter bags and electrostatic filters, as they cannot withstand very high temperatures. In typical nanoparticle production, the exhaust gas is cooled by air.

[0053] In accordance with the present invention, large amounts of nanomaterials are produced (1000-100000 t / y or more depending on the size of the plant) by utilizing conventional power plants and fuels, such as renewable green fuels.

[0054] The invention will now be described in detail by way of two non-limiting examples. [Brief explanation of the drawings]

[0055] [Figure 1] 1 is a schematic diagram of a first embodiment of the present invention for producing heat and metal oxide nanoparticles. FIG. [Figure 2] FIG. 1 is a schematic diagram of a second embodiment of the present invention for producing heat and metal oxide nanoparticles. DETAILED DESCRIPTION OF THE INVENTION

[0056] FIG. 1 is a schematic diagram of a first embodiment of the present invention for producing heat and metal oxide nanoparticles.

[0057] Overall, reference number 1, enclosed in a dotted line, represents the input of precursor materials required for the nanoparticle production portion of the present invention, which may optionally be in a separate space or container, while reference number 2, also enclosed in a dotted line, represents the input required for the heat generation portion of the present invention, which may optionally be in another separate space or container.

[0058] In the embodiment of FIG. 1, fuel consisting of liquid ethanol is supplied from a fuel tank 3 to a buffer tank 4 containing a mixer.

[0059] The precursor material, assumed in this example to be solid lithium nitrate (LiNO3), is fed from the (LiNO3) powder storage location 5 to the buffer tank 4 and dissolved in ethanol to form a stable solution without solid precipitation.

[0060] The liquid titanium tetraisopropoxide (TTIP) precursor is then mixed with the ethanol and lithium nitrate solution just before entering the burner 8. For this reason, it is practical to first feed the ethanol and lithium nitrate solutions into a separate mixer tank 7 and then add the titanium tetraisopropoxide (TTIP) precursor from storage 6 to said mixer tank 7, which can be, for example, a static pipe mixer or a mixer tank. For the operation of the burner, it is important that all precursors are completely dissolved and remain in solution and that no precipitates form.

[0061] In other embodiments of the invention, only one precursor material may be used, so that the tank and mixer 7 are not required, or more than one precursor material may be fed into the same buffer tank 4.

[0062] Additionally, AgNO3 can be dissolved in the precursor solution and fed into the burner along with LiNO3 and TTIP to enhance the performance of LTO nanomaterials in the produced batteries.

[0063] Alternatively, AgNO3 can be added before the TTIP is added, so that it can be mixed into the ethanol in the same buffer tank where the LiNO3 is added to the ethanol.

[0064] The ethanol-LiNO3-TTIP solution is then fed to a combustion device having a burner 8, where the ethanol-LiNO3-TTIP precursor material is combusted.

[0065] The flame temperature produced by the ignition gas in burner 8 is typically around 2000°C, usually 1800-2100°C, which causes decomposition of LiNO3 and TTIP in an oxidizing atmosphere and the formation of metallic Li and Ti. Li, Ti, and oxygen then react to form Li4Ti5O 12 (LTO) to form Li4Ti5O 12 The formation of firmed Li4Ti5O is sensitive to the molar ratio of lithium to titanium in the precursor. For example, a stoichiometric ratio of Li / Ti, i.e., 4:5, could be used. 12 can be directly used as an anode material in Li-ion batteries.

[0066] Another lithium titanium oxide (Li2TiO3LTO) for producing cathode material Li2TiO3 for lithium ion batteries can be formed by varying the Li / Ti ratio of the supplied precursor solution.

[0067] An oxidizing atmosphere is achieved by supplying air, e.g., by a blower 9, which oxidizes the precursor material and ethanol, producing heat. Instead of air, a gas containing more oxygen than air can be used, even pure oxygen gas, O2. The heat is mostly the result of the combustion of the fuel, but also partly due to the chemical reaction and decomposition of the precursor material. In this case, the decomposition / reaction of LiNO3 consumes heat, and the decomposition / reaction of TTIP produces heat.

[0068] Burner 8 uses compressed air 10 to disperse the ethanol fuel-(Li,Ti) precursor mixture into small droplets (mist, preferably droplets less than 100 μm). A portion of the air is typically consumed by the oxidation reaction of the precursor material. The burner is a liquid fuel burner, whereby the mixture of air and fuel / precursor droplets is ignited and combusted at high temperatures, decomposing the precursor to Li / Ti oxides and the ethanol fuel to form CO and HO.

[0069] Within the combustion system, associated with the burner 8, is a boiler 11, which comprises a furnace in which the fuel and precursor mixture is burned, and further comprises a hot surface (not shown) for transferring heat from the combustion products, which is recovered by a heat exchanger 12 used to recover heat and cool the flue gases resulting from the combustion.

[0070] Although in this example only heat is produced, the invention may also be used in conjunction with power plants that produce both heat and power, for example by steam superheating, where the heat recovery steam generator operates as a boiler, i.e., an energy recovery heat exchanger, that recovers heat from a hot gas stream resulting from combustion to produce steam that may be used to drive a steam turbine or used as process steam in an industrial process.

[0071] Thus, in this example, a heating plant typically used to generate heat was expanded to produce LTO nanomaterials simply by dissolving its precursor in ethanol. Now, both heat and LTO nanoparticles are produced in this power plant, adding value to the heat production.

[0072] For high electrochemical performance of LTO in Li-ion batteries at high charge / discharge rates, it is important that the LTO primary particles are nanosized, preferably 30-50 nm in size, to achieve short electron and ion conduction paths. Ag nanoparticles with sizes of 1-3 nm on the surface of the LTO particles (30-50 nm) further enhance the electron and ion conductivity of the LTO particles, which improves the performance of LTO nanomaterials in Li-ion batteries.

[0073] The produced LTO nanoparticles are filtered by a filtration device 13, such as a regular baghouse filter commonly used in power plants for fuel gas purification, and collected in an LTO container 14. The purified exhaust gas is released into the air through a stack 15.

[0074] Electrostatic filters could also be used: thanks to a heat exchanger placed before the filter, the exhaust gases are cooled, allowing the collection of nanoparticles.

[0075] This is an original and advantageous part of the present invention compared to the prior art, where the exhaust gases in the power plant are cooled, for example by air, and the filter bags have to be dimensioned for very large amounts of gas, making their cost several times higher.

[0076] Thus, the heat exchanger used in the present invention has two functions: in addition to recovering heat, it also cools the exhaust gas to a temperature suitable for flue gas cleaning systems (preferably below 200°C).

[0077] FIG. 2 is a structural diagram of a second embodiment of the present invention for producing thermal and metal oxide nanoparticles.

[0078] The fuel used in this example is hydrogen (H2) gas, which is channeled from storage 3' and burned, for example, by a ring burner 8' with several individual burner heads forming a ring. However, any gas burner could be used to create a controlled flame by mixing the fuel gas, here hydrogen, with an oxidizer such as ambient air or supplied oxygen and allowing it to ignite and burn.

[0079] Droplets of aqueous solutions of inorganic sulfates of various metals, such as Li2SO4, NiSO4, MnSO4, and CoSO4, are sprayed from a storage location 5' (not distinguished in the diagram) onto the center of the burner ring. Instead of, or in addition to, Li2SO4, a useful Li-precursor is LiNO3. The droplet size can be on the order of 10-100 micrometers.

[0080] The oxidizing atmosphere is achieved by supplying hydrogen gas along with combustion air from storage location 9, thus oxidizing the precursor material and hydrogen to produce heat.

[0081] (a) The inorganic metal precursors completely decompose in the flame of the burner, achieved by the ignition gas, and then react to form the desired Li-Ni-Mn-Co-O final product, which consists of various oxides of the metals Li, Ni, Mn, and Co. They have the general formula LiNi x Mn y Co z O2 (e.g., LiNiMnCoO2, abbreviated as Li-NMC, LNMC, NMC, or NCM). The proportion of metals can be varied by changing the concentration in the aqueous precursor.

[0082] (b) The temperature profile of particle formation can be varied by changing the fuel to precursor feed rate ratio, so that the inorganic metal precursor does not vaporize but reacts in the droplet phase to produce the desired final LiNi x Mn y Co z It is possible to achieve conditions that result in the formation of an O2 product. The proportion of metal can be varied by changing the concentration in the aqueous precursor. In this case, the final product consists of larger particles.

[0083] As in the embodiment of FIG. 1, within the combustion apparatus, associated with the burner 8′, is a boiler 11, which comprises a furnace in which the fuel and precursor mixture is combusted, and which further comprises a hot surface (not shown) for transferring heat from the combustion products, which is recovered by a heat exchanger 12 used to recover heat and cool the flue gases resulting from the combustion.

[0084] The produced Li-NMC particles are collected by a conventional baghouse filter 13 commonly used in power plants for flue gas cleaning and collected in a Li-NMC container 14. The cleaned exhaust gas is discharged into the air through a stack 15.

[0085] As with the embodiment of FIG. 1, here only heat is produced, but electricity could also be produced.

[0086] Thus, in this example, the heating plant was expanded to produce Li-NMC material by simply dissolving its precursor in water and spraying the solution into a flame of gases typically used to generate heat without a metal precursor. Now, both heat and Li-NMC particles are produced in this power plant, adding value to heat production.

[0087] "Example 1" In a process according to FIG. 1, for example, a 10 MW (fuel-powered) plant can be supplied with lithium and titanium precursors in a stoichiometric ratio (a solution of 2 moles / liter or less in a liquid fuel (e.g., ethanol) to produce LTO nanomaterials.

[0088] A solution of 51 kg / h LiNO3, 280 l / h TTIP, and 1400 l / h ethanol was combusted to produce 71 kg / h LTO nanomaterial. Silver doping of the particles was achieved by adding AgNO3 to the precursor.

[0089] LTO material with a primary particle size of 20 nm, as measured by transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET), was produced in a laboratory-scale burner. The specific surface area (SSA) of the produced nanoparticles was 87 m 2 / g, and the silver (Ag) concentration was measured to be 1 wt% by inductively coupled plasma mass spectrometry (ICP-MS).

[0090] "Example 2" In a process according to FIG. 2, for example, aqueous solutions of up to 2 moles / liter of Li, Ni, Mn, and Co precursors can be sprayed as small droplets (droplet size less than 100 um) at 10 MW (fuel-powered) gas-fired power to produce NMC Li-ion battery cathode material plants.

[0091] As a result, aqueous solutions of 59 kg / h LiNO3, 79 kg / h NiSO4, 26 kg / h MnSO4 and 27 kg / h CoSO4 are fed to produce 83 kg / h of NMC622 material.

[0092] "Example 3" The production of lithium titanate (LTO) was tested in a traditional light fuel oil (LFO) burner. A commercially available LFO burner was converted to an ethanol burner according to the manufacturer's recommendations.

[0093] A fuel mixture of 49 g / h Li-nitrate and 260 ml / h Ti-tetraisopropoxide in 1.3 l / h ethanol was burned in a modified LFO burner to produce 83 g / h LTO powder.

[0094] The morphology and chemical composition of the collected powder samples were analyzed using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS), the elemental carbon (soot) and organic carbon contents were determined by organic carbon and elemental carbon (OC / EC) analyzer, and the LTO crystalline phase was analyzed by X-ray powder diffraction (XRD).

[0095] The production rate was calculated to be 0.5 g / h with a collection efficiency of 60%.

[0096] As can be seen, some particles were lost in the heat exchanger and flue gas line. The total carbon content of the product was 1.24%, of which the organic carbon content was 1.07% and the soot content was 0.15%. XRD showed that crystalline lithium titanate particles were produced.

Claims

1. 1. A method for the combined production of nanomaterials and heat, comprising: a) providing at least one precursor material by atomization in the form of droplets of 10-100 μm size or in the form of solid particles suspended in a gas, and burning said precursor material at a sufficient temperature to decompose and oxidize it by feeding fuel to a combustion device (11) for heat and production of nanoparticles; b) recovering the heat generated mostly from the combustion of said fuel and partly from the chemical reaction and decomposition of said precursor material using at least one heat exchanger (12); c) cooling the combusted fuel; d) collecting the nanoparticles produced in the form of oxides produced by the combustion; A method comprising:

2. 2. The method of claim 1, wherein prior to step a), the at least one precursor material is dissolved in the fuel in one or more separate containers (4, 7) or mixers before feeding them into the combustion device (11).

3. A method as described in claim 1 or 2, wherein compressed air is supplied to the combustion device (11) to disperse the mixture of the at least one precursor material and the fuel into small droplets.

4. The solution of the at least one precursor material fed to the combustion device (11) contains silver nitrate (AgNO ３ 4. The method according to claim 1, wherein the hydroxybenzoate is dissolved in the hydroxybenzoate.

5. The method of claim 1, wherein silver nitrate (AgNO3), the at least one precursor, and the fuel are fed separately to a buffer tank before being fed to the combustion device.

6. 2. The method of claim 1, wherein the at least one precursor material and the fuel are fed separately to the combustion device (11).

7. 7. The method of claim 6, wherein the fuel is a liquid fuel and the at least one precursor material is supplied by spraying in the form of droplets of a solution of the precursor material.

8. 8. The method of any one of claims 1 to 7, wherein the at least one precursor material is selected from sulfates, chlorides, nitrates, carbonates, and hydroxides of lithium (Li), titanium (Ti), nickel (Ni), manganese (Mn), cobalt (Co), aluminum (Al), iron (Fe), phosphorus (P), silver (Ag), silicon (Si), carbon (C), niobium (Nb), zinc (Zn), and sulfur (S), and titanium tetraisopropoxide (TTIP).

9. 9. The method of any one of claims 1 to 8, wherein the fuel is ethanol, methanol, propanol, natural gas, liquefied natural gas, LNG, or hydrogen, acetylene, methane, or propane.

10. The oxidation of the precursor material may be performed with air, a gas containing more oxygen than air, or pure oxygen gas (O ２ 10. The method according to any one of claims 1 to 9, wherein the method is carried out by supplying an oxidizer such as argon to the combustion device (11).

11. The nanoparticles produced in the form of oxides from the combustion of the precursor material are lithium titanium oxide (Li ２ TiO ３ or Li ４ Ti ５ O １２ (LTO), lithium nickel manganese cobalt oxide (LiNi ｘ Mn ｙ Co ｚ O ２ , Li-NMC), lithium iron phosphate (LiFePO ４ , LFP), lithium manganese oxide (LMO, LiMn ２ O ４ , Li ２ MnO ３ , LiMnO ２ , and / or Li ２ MnO ２ 11. The method according to claim 1 , wherein the material is a composite material (LMO) and / or a composite material (LMO).

12. Li ４ Ti ５ O １２ 12. The method of claim 11, wherein a 4:5 lithium / titanium stoichiometry is used in the precursor feed to form

13. Li of 30 to 50 nm in size ４ Ti ５ O １２ 14. The method of claim 13, wherein nano-sized LTO particles of 1-3 nm in size are produced with Ag nanoparticles on the surface of the LTO particles.

14. Li of 30 to 50 nm in size ４ Ti ５ O １２ 14. The method of claim 13, wherein nano-sized LTO particles of 1-3 nm in size are produced with Ag nanoparticles on the surface of the LTO particles.

15. 15. A method according to any one of claims 1 to 14, wherein the combustion temperature used is sufficient to cause decomposition and reaction of the precursor material, such as from 1000 to 2500°C.

16. 16. The method according to any one of claims 1 to 15, wherein a layer of carbon is provided on the nanoparticles by incomplete combustion.

17. 17. The method of any one of claims 1 to 16, wherein at least a portion of the recovered heat is utilized for other industrial processes or for heating buildings.

18. 18. The method according to any one of claims 1 to 17, wherein at least a portion of the recovered heat is converted into electricity, preferably by means of a steam generator.

19. a) a combustion device (11); b) means for supplying at least one precursor material, a fuel and an oxidant to said combustion device for combustion and nanomaterial production, said precursor material being supplied by atomization in the form of small droplets of 10-100 μm in size or as solid particles suspended in a gas; c) a heat exchanger (12) for recovering heat from the combustion device (11) and cooling the combusted fuel, the heat being mostly produced by combustion of the fuel and partly from chemical reactions and decomposition of the precursor material; d) means (13) for collecting nanomaterials in the form of oxides from said combustion of said precursor material; A system for the combined production of nanomaterials and heat comprising:

20. 20. The system of claim 19, wherein the combustion device (11) is an industrial heat plant, producing heat that is used for other industrial processes or for heating buildings.

21. 20. The system of claim 19, wherein the combustion device (11) is an industrial power plant, producing heat and electricity.

22. 22. The system of claim 21, wherein the industrial power plant is a cogeneration CHP plant.

23. 23. The system according to any one of claims 19 to 22, wherein the combustion device (11) comprises a burner (8) for liquid fuel.

24. 23. The system according to any one of claims 19 to 22, wherein the combustion device (11) comprises a burner (8) for gaseous fuel, such as a ring burner (8'), several individual burner heads forming a ring.

25. 25. The system according to any one of claims 19 to 24, wherein the means (13) for collecting the nanomaterials is a bag filter (13) or an electrostatic precipitator or other filtering device or a cyclone or a scrubber.

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