Rock particle preparation, use and process for the production thereof

Abstract

The present invention describes a preparation of rock particles, use thereof, and a process for obtaining it by comminution, that is to say, a top-down process. The rock particle preparation of the invention addresses these and other issues and exhibits a particular composition, purity, particle size distribution, and specific surface area, making it useful in a range of applications. The invention also discloses a method for obtaining particles of mineral species comprising rock, for example basaltic rock, by controlled comminution without chemical reactions or contamination with reagents typically used in nanoparticle synthesis. The present invention, in clear contrast to the prior art, enables large-scale production of rock particles with high purity, a defined particle size distribution, and a very high specific surface area, thereby making the use thereof in various industrial applications feasible.

Description

Rock particle preparation, use and process for obtaining it. Field of Invention

[0001] The present invention is situated in the field of materials engineering and nanotechnology. More specifically, the invention describes a preparation of rock particles, its use, and a process for obtaining it by comminution, i.e., a top-down process. The particle preparation of the invention solves these and other problems and has a peculiar composition, purity, particle size distribution, and specific surface area, being useful in a variety of applications. The invention also discloses a process for obtaining particles of rock-containing mineral species, for example basaltic rock, by controlled comminution and without chemical reactions or contamination with reagents typical of nanoparticle synthesis.The present invention, in stark contrast to the prior art, provides for the large-scale production of rock particles with high purity, a defined particle size distribution, and a very high specific surface area, making their use in various industrial applications practically feasible. Background of the Invention

[0002] Volcanic rocks containing plagioclase and pyroxene (components of basalt fiber) are found, for example, throughout the Central-South region of Brazil in the geological formation known as the Serra Geral Formation (FSG).

[0003] Adding value to materials extracted from nature is a constant challenge in the technical field of materials engineering. The current high demand for materials for a wide variety of applications makes the development of alternatives to the most commonly used materials fundamental. Furthermore, adding value relates to the more rational use of materials extracted from nature. For example, it is more common to use... Basaltic rocks from the Serra Geral Formation (FSG) are used to produce paving stones and building materials, for example in the construction of basements, sinks and sidewalks.

[0004] Thus, the development of new materials based on available resources to obtain alternative materials for high-tech applications is a constant demand in the field of materials engineering, and technologies in this technical area can have a significant impact on the economic development of a region, as well as a significant environmental impact by promoting the more rational use of materials extracted from nature.

[0005] Therefore, its incorporation into high value-added products is a constant need in the technical field.

[0006] Of particular relevance in the context of the present invention is the difference between: (i) preparations containing a fraction of nanoparticles among the other particles; (ii) preparations containing particles predominantly or entirely in the nanometer particle size range; and (iii) preparations of nanoparticles predominantly or entirely in the nanometer particle size range with a defined particle size distribution profile. The present invention provides these last two.

[0007] Rock particle preparations may eventually contain small fractions of nanoparticles, but the predominance of much larger particles, in the micrometer / micron range, prevents the characterization of such preparations as true nanoparticle preparations. Furthermore, it is known that the behavior of materials at the nanoscale changes substantially and, therefore, the availability on a large scale and with high purity of a preparation containing rock particles predominantly or entirely in the nanometer range and with high purity, without contaminations typical of synthesis processes, is highly desirable. The present invention solves these and other technical problems.

[0008] Grinding / comminution / pulverization methods usually aim to To increase the specific surface area and enable varied industrial uses. In the case of rocks or materials containing rocks, known methods are limited to obtaining particles with a granulometry in the micrometer range. As of the date of filing this patent application, the present inventors are unaware of any rock grinding methods that would yield preparations entirely containing nanoparticles.

[0009] Based on the literature reviewed, no documents were found that anticipated or suggested the teachings of the present invention. Summary of the Invention

[0010] The present invention solves several problems of the prior art related to rock preparations with predominantly or entirely nanometric particle size distribution.

[0011] One of the aims of the invention is to provide a preparation of rock nanoparticles with high purity.

[0012] One of the objects of the invention is to provide a preparation of rock particles of chemically defined composition.

[0013] One of the objects of the invention is to provide a preparation of rock particles with d50 to d99 in the nanometer granulometric range.

[0014] One of the objects of the invention is to provide a preparation of rock particles with d90 to d99 in the nanometer granulometric range.

[0015] In some embodiments, the rock particle preparation has an average particle size (d50) between 403 and 516 nm.

[0016] One of the objects of the invention is to provide a preparation of rock particles in the granulometric range predominantly below 1000 nanometers.

[0017] In some embodiments, the prepared rock particles have the following particle size distribution: d10: between 132 and 153 nm; d50: between 403 and 516 nm; and d90: between 5573 and 7986 nm.

[0018] The particle preparation of the invention is useful in various applications. including: modulating or improving the mechanical properties of steels, metallic and non-metallic alloys, ceramics and / or polymers; composite materials; doping materials to modulate electromagnetic properties for use in electronic components, battery cells, energy storage systems, solar panels, sensors and piezoelectric actuators; modulating the optical properties of glasses or other transparent or translucent materials; use as a component of catalysts; in the preparation of stable liquid / colloidal compositions.

[0019] Another object of the invention is to provide a process for preparing a rock particle preparation by a top-down approach, i.e., by comminution without chemical or mechanochemical synthesis. This process is scalable and suitable for the economic viability and effective availability of preparations.

[0020] The invention process comprises the following steps: - feeding rock particles to a comminuting machine selected from: high-energy mill and steammill, - Adjust the selected comminution conditions from among: - in a high-energy mill: - Suspend particles to be comminuted in a liquid, at a concentration between 1 and 90% w / w, and stabilize the suspension until a stable colloidal suspension is obtained; and - Place the aforementioned suspension and grinding balls with a selected diameter between 5 µm and 1.3 mm in the grinding chamber; adjust the mill rotation speed between 500 and 4500 rpm; and grind the particles at a temperature below 60 °C; or - In a jet mill with superheated fluid or a Steammill, feed particles smaller than 40 micrometers; adjust the air classifier rotation between 1,000 and 25,000 rpm; adjust the compressed steam pressure between 10 and 100 bar and the temperature between 230 and 360 °C. - comminute the particles until the desired particle size distribution is obtained.

[0021] In one embodiment, the stabilization of the colloidal suspension to be placed in the grinding chamber of the aforementioned high-energy mill is selected from among: adjusting the pH of the polar liquid medium to the range between 2 and 13, and optionally adding surfactants; or adding surfactants to the supporting liquid medium.

[0022] In one embodiment, the process of obtaining the rock particles involves grinding in a high-energy mill operating with spheres of special materials, such as Zirconia, Yttria-stabilized Zirconia, Rock-stabilized Zirconia, or combinations thereof, by adjusting specific parameters.

[0023] In another embodiment, the process of obtaining rock particles includes grinding in a jet mill with superheated steam, or steammill, by adjusting specific parameters.

[0024] These and other objects of the invention will be immediately appreciated by those skilled in the art and will be described in detail below. Brief Description of the Figures

[0025] The following figures are presented:

[0026] Figure 1 shows the particle size distribution curves of the triplicates from the first rock sample analysis (SN 20 002).

[0027] Figure 2 shows the cumulative volume curves of the triplicates from the first rock sample analysis (SN 20 002).

[0028] Figure 3 shows the particle size distribution curves of the triplicates from the second rock sample analysis (SN 20 002).

[0029] Figure 4 shows the cumulative volume curves of the triplicates from the second rock sample analysis (SN 20 002).

[0030] Figure 5 shows the particle size distribution curves of the triplicates from the third rock sample analysis (SN 20 002).

[0031] Figure 6 shows the cumulative volume curves of the triplicates from the third rock sample analysis (SN 20 002).

[0032] Figure 7 shows the compiled particle size distribution curves from all rock samples and triplicates (SN 20 002).

[0033] Figure 8 shows the compiled cumulative volume curves from all rock samples and triplicates (SN 20 002).

[0034] Figure 9 shows the zeta potential graph of the analyses of all rock samples (SN 20 002). The x-axis shows time in seconds, the left y-axis shows the zeta potential in mV, and the right y-axis shows the pH.

[0035] Figure 10 shows a generic diagram of the process for the “micronization” of rocks. Detailed Description of the Invention

[0036] The present invention solves several problems of the prior art and provides a rock particle preparation that simultaneously meets the following technical characteristics: particles predominantly or entirely in the nanometer granulometric range; high purity; an industrial-scale process that enables supply and use on an economical scale. The preparation comprises basaltic rock particles, plutonic rock, or combinations thereof.

[0037] In the context of the present invention, the expression "basaltic rock particle" encompasses various chemical entities comprising basaltic rock composition as defined by the TAS diagram (Total Alkali vs. Silica diagram, which is known to one skilled in the art - % by mass of Na2U + K2O by % by mass of Si2O). Including but not limited to Basalt, Basaltic Andesite, Andesite and Dacite as defined in the TAS diagram. Comprising micro, sub-micro and nanoparticles, according to particle size distribution.

[0038] In the context of the present invention, the expression "plutonic rock particle" encompasses particles of various chemical entities formed by the cooling of magma at depth, that is, within the lithosphere, in such a way that the material does not erupt to the surface. Terrestrial rocks. They are also known as intrusive rocks. Including but not limited to granite, diorite, tourmaline, syenite, and gabbro. Comprising micro, sub-micro, and nanoparticles, according to their grain size distribution.

[0039] The invention is also defined by the following clauses.

[0040] A preparation of rock particles comprising a content equal to or greater than 95% by weight of rock particles, wherein 10% to 50% of the particles (d10 to d50) are in the granulometric range of 10 to 1000 nanometers (nm).

[0041] Particle preparation as defined above comprising a content of 99% or more by weight of rock particles.

[0042] A preparation of particles as defined above, wherein the rock said is basaltic rock, plutonic rock, or combinations thereof. In one embodiment, the rock said is basaltic rock. In another embodiment, the rock said is plutonic rock.

[0043] Particle preparation as defined above wherein 50% to 99% of the particles (d50 to d99) are in the particle size range of 403 to 19426 nanometers (nm).

[0044] Particle preparation as defined above wherein 90% to 99% of the particles (d90 to d99) are in the particle size range of 5573 to 19426 nanometers (nm).

[0045] Prepared particles as defined above having a particle size distribution of d10: between 132 and 153 nm; d50: between 403 and 516 nm; and d90: between 5572 and 7986 nm.

[0046] Particle preparation as defined above wherein the specific surface area is from 0.5 to 150 m² 2 / g.

[0047] Particle preparation as defined above wherein the average specific surface area is 40 to 70 m². 2 / g.

[0048] The particle preparation described above can be used to adjust the rheological properties of other particle or nanoparticle preparations, adjusting packing levels, flowability, void fractions, or other properties of the final preparation.

[0049] The particle preparation described above is used for the preparation of: stable colloidal compositions; steels, metallic and non-metallic alloys, ceramics and / or polymers; composite materials, electronic components, battery cells, energy storage systems, piezoelectric sensors and actuators, solar panels; glasses, glass-ceramics or other transparent and translucent materials; catalysts.

[0050] Process for obtaining rock particles comprising the following steps: - feeding rock particles to a comminuting machine selected from: high-energy mill and steammill, - Adjust the selected comminution conditions from among: - In a high-energy mill: suspend particles to be comminuted in a liquid, at a concentration between 1 and 90% w / w, and stabilize the suspension until a stable colloidal suspension is obtained; place the suspension and grinding spheres with a diameter selected between 5 µm and 1.3 mm in the grinding chamber; adjust the mill's rotation speed between 500 and 4500 rpm; and grind the particles at a temperature below 60 °C; or - In a jet mill with superheated fluid or a Steammill, feed particles smaller than 40 micrometers; adjust the air classifier rotation between 1,000 and 25,000 rpm; adjust the compressed steam pressure between 10 and 100 bar and the temperature between 230 and 360 °C; - comminute the particles until the desired particle size distribution is obtained.

[0051] The process, as described above, involves selecting the stabilization of the colloidal suspension to be placed in the grinding chamber of the high-energy mill from either: adjusting the pH of the polar liquid medium to the range between 2 and 13, and optionally adding surfactants; or adding surfactants to the supporting liquid medium.

[0052] The process, as described above, further comprises a pre-comminution step of the rock particles before feeding them to the comminution equipment, said pre-comminution being conducted until it reaches... particles with a maximum size less than or equal to 40 micrometers. In one embodiment, said pre-comminution is conducted until an average particle size between 1 and 40 micrometers is achieved.

[0053] A process in which the aforementioned pre-comminution is carried out in a ball mill, disc mill, or high-energy mill.

[0054] A process in which the aforementioned pre-comminution is carried out by tumbling in a ball mill, or pellet mill.

[0055] In one embodiment, the pre-comminution particles have a maximum moisture content of 2% by weight.

[0056] In one embodiment, the pre-comminution stage comprises feeding the initial rock into the mill and selecting the resulting powder in the classifier. The fraction of powder that does not meet the production specification is reintroduced into the mill in a closed-loop operation, while the fraction specified for the product is collected in the air filter. Under the working conditions used in this test, the airflow is kept constant, as is the mill rotation speed. The process parameters used to obtain the desired micronization for the starting rock were the rock feed rate and the classifier rotation speed.

[0057] In a pre-comminution implementation, the airflow in the system is 1,200 m³ / h and the rotation speed of the ball mill is maintained at 32 rpm. The rotation speeds of the rock feed screw in the mill and the air classifier were 2-14 rpm and 800-2800 rpm, respectively, so that the circulation flow in the mill used stabilized between 300 and 350 kg / h.

[0058] The process, as described above, comprises the following steps: - feeding a high-energy mill with rock particles, wherein said particles are micrometric; - feed the mill with a liquid and adjust the pH to the range between 5 and 10; - feed the aforementioned mill with spheres with a diameter selected between 50 µm and 400 µm; - Adjust the mill's rotation speed between 2000 and 4000 rpm; and - Grind the particles at a temperature below 60 °C until the desired particle size distribution is obtained.

[0059] The process, as described above, involves a high-energy mill of the agitated type, and the spheres are selected from: zirconia, silicon carbide, alumina, optionally stabilized with yttria or rock, or combinations thereof.

[0060] The process, as described above, involves a superheated jet mill or Steammill adjusted with the following parameters: air classifier rotation at 20,000 rpm; compressed steam pressure at 50 bar; and superheated fluid temperature at 280 °C.

[0061] The process is as described above, where the operating pH in the mill is between 6 and 10.

[0062] The process is as described above, where the operating temperature in the mill is 30 to 40 °C.

[0063] In some embodiments, the particle preparation of the invention comprises particles with defined particle size fractions, such as, for example, a preparation with particles entirely between 100 and 1000 nm, a preparation with particles entirely between 1 and 100 nanometers, and preparations with particles of intermediate values ​​and with particle size fractions of defined value.

[0064] In some embodiments of the present invention, as is already common practice in the industry, the distribution of particle size fractions is defined by d10, d50, d90 and occasionally d99, notations which reflect the cumulative % volume of particles corresponding to each notation, d10 referring to 10% of the particle volume, d50 to 50% of the volume and so on.

[0065] Product comprising the particle preparation as described above and a material selected from metal, non-metal, ceramic, polymer, glass, glass-ceramics or combinations thereof.

[0066] Product as described above being a colloidal composition. stable; steels, metallic and non-metallic alloys, composite materials, electronic components, battery cells, energy storage systems, piezoelectric sensors and actuators, solar panels; transparent and translucent materials; catalysts.

[0067] The particle preparation of the invention is useful in various applications, including: the preparation of stable colloidal suspensions; the modulation or improvement of the mechanical properties of steels, metallic and non-metallic alloys, ceramics and / or polymers; composite materials; the doping of materials to modulate electromagnetic properties for use in electronic components, battery cells, energy storage systems, solar panels, piezoelectric sensors and actuators; the modulation of optical properties of glasses or other transparent materials; and use as a component of catalysts.

[0068] In one embodiment, the use of the particle preparation of the invention provided stable liquid compositions or colloidal suspensions, in which the particles remain in suspension for an extended period, thus providing a long shelf life.

[0069] The process for obtaining rock particles differs from similar processes because it is a top-down process, without chemical reactions or mechanochemistry. The fact that pure or highly pure rock particles are used for comminution allows for the production of highly pure particle preparations, since the process does not add impurities or lead to the formation of reaction products, as is the case with state-of-the-art bottom-up, synthetic, or mechanochemical processes.

[0070] The invention process comprises the following steps: - feeding rock particles to a comminuting machine selected from: high-energy mill; and steammill, - Adjust the selected comminution conditions from among: - in a high-energy mill: - to suspend particles to be comminuted in a liquid, at a concentration between 1 and 90% w / w, and stabilize the suspension until a stable colloidal suspension is obtained; and - Place the aforementioned suspension and grinding balls with a selected diameter between 5 µm and 1.3 mm in the grinding chamber; adjust the mill rotation speed between 500 and 4500 rpm; and grind the particles at a temperature below 60 °C; - In a superheated jet mill or Steammill, feed particles smaller than 40 micrometers; adjust the air classifier rotation between 1,000 and 25,000 rpm; adjust the compressed steam pressure between 10 and 100 bar and the temperature between 230 and 360 °C; and - comminute the particles until the desired particle size distribution is obtained.

[0071] Reducing the average particle size before the process, as demonstrated above, is particularly useful for improving the performance of the subsequent comminution process in a high-energy mill, as demonstrated in Examples 1-4, or in a steam mill comminution process, described in Example 3 below.

[0072] In one embodiment, the process involves wet milling in a high-energy mill and enables, on an industrial scale, for the first time, the production of rock particles predominantly or entirely in the nanometer granulometric range. In embodiments where comminution is performed in high-energy wet mills, the stabilization of the colloidal suspension to be placed in the milling chamber of the high-energy mill is a very important step, and is selected from among: adjusting the pH of the polar liquid medium to the range between 2 and 13, and optionally adding surfactants; or adding surfactants to the supporting liquid medium.

[0073] In one embodiment, a known prior art mill is used, such as a high-energy mill with yttria-stabilized zirconia (ZrÜ2 + Y2O3) beads, by adjusting specific parameters, including rotation time, pH, and temperature. In one embodiment, the grinding medium includes zirconia beads, ZTA (Zirconia (Reinforced with alumina or yttrium) and alumina. Preferably, zirconia spheres stabilized with 5% w / w yttria are used.

[0074] In another embodiment, the process involves comminution by jet mill with superheated steam (steammill), to which particles smaller than 40 microns are fed, with the rotation of the air classifier adjusted between 1,000 and 25,000 rpm, the pressure of the compressed steam between 10 and 100 bar, and the temperature between 230 and 360 °C.

[0075] Examples

[0076] The examples shown here are intended only to illustrate some of the various ways of carrying out the invention, without, however, limiting its scope.

[0077] Example 1 - Wet grinding process of basaltic rock in a high-energy mill

[0078] A Labstar LS01 ball mill (Netzsch) was fed with micrometric basaltic rock particles. The process involved high-energy wet milling. The particle suspension was 17.7 wt%, consisting of approximately 3500 g of milli-Q water + 10 M NaOH and 750 g of the solid sample, which was prepared and stabilized in the mill's mixing tank at pH 9 and titrated with 10 M NaOH. The milling spheres used were yttria-stabilized zirconia, 400 µm in diameter. The milling chamber was filled to 80% vol and the suspension temperature was below 40 °C. The mill rotation speed was set to 3000 rpm and milling was conducted for 8 hours. To stabilize the suspension at pH 9, 10 M NaOH was added during milling, and samples were taken periodically to measure particle sizes.

[0079] Particle size measurements were performed using a Fritsch Analysette 22 instrument, with an accessory unit for wet particle size measurement. Particle size distribution measurements were performed using static light scattering. The analytical medium was distilled water. An aliquot of the suspension with 17.7% w / w, during the process of The grinding process was analyzed in ten repetitions using the equipment. The results in Table 2 present the measurements (average of 10 measurements) and the PDT (particle size distribution) obtained at each grinding time under the conditions indicated above.

[0080] Example 2 - Comminution of basaltic rock by Steammill

[0081] In this embodiment, basaltic rock particles with the distribution profile dD90=22.3 pm; D50=8.88 pm; d10=2.77 pm were fed into a steammill.

[0082] Next, the air classifier rotation speed was adjusted to 20,000 rpm and the compressed steam pressure to 50 bar. The temperature of the superheated fluid was 280 °C.

[0083] Example 3 - Characterization of the particles obtained

[0084] Results of particle size analyses

[0085] Table 1 shows the particle size distribution (PSD) of basaltic rock.

[0086] Table 1: DTP of basalt rock.

[0087] Figures 1-6 show the curves corresponding to the particle size distribution profile of three samples of the present invention. The x-axis shows the equivalent particle diameter in micrometers, the left y-axis the cumulative volume %, and the right y-axis the volume %.

[0088] Results of zeta potential analyses

[0089] Table 2 shows the results of the mean zeta potential analyses of each of the basaltic rock nanoparticle samples analyzed.

[0090] Table 2: Results of zeta potential analyses of rock samples.

[0091] Figure 9 shows the result of the zeta potential analysis of each of the basalt rock nanoparticle samples. The x-axis shows the time in seconds, the left y-axis shows the zeta potential in mV, and the right y-axis shows the pH.

[0092] Summary of results

[0093] The summary compiling the average values ​​obtained for the rock sample (SN 20 002) from all the characterization analyses performed is presented in Table 3.

[0094] Table 3: Summary of the results of the rock sample analyses (SN 20 002). * average values

[0095] The results for zeta potential, pH, and electrical conductivity obtained for the rock suspension sample (SN 20 002) are presented in Table 4.

[0096] Table 4: Results for zeta potential, pH, and electrical conductivity of rock samples (SN 20 002).

[0097] The particle size results d10, d50 and d90 obtained for the rock sample (SN 20 002) are presented in Table 5. The compilation of the particle size distribution curves and accumulated volume obtained for the rock sample (SN 20 002) are presented in Figure 7 and Figure 8, respectively.

[0098] Table 5: Particle size results of the rock sample (SN 20 002)

[0099] Example 4 - Pre-comminution

[0100] The grinding process was carried out by tumbling in a ball mill, or pellet mill, consisting of feeding the initial rock into the mill (1) and then Selection of the powder obtained in the classifier (2). The fraction of powder that does not meet the production specification is reintroduced into the mill, in a closed operating circuit, while the fraction specified for the product is collected in the air filter (3). Under the working conditions used in this test, the airflow is kept constant, as is the mill rotation speed. The process parameters used to obtain the desired micronization for the starting rock were the rock feed rate (5) and the classifier rotation speed (6).

[0101] Figure 10 shows a generic diagram of the process for performing the “micronization” of rocks.

[0102] The airflow in the system was 1,200 m³ / h and the ball mill rotation speed was maintained at 32 rpm for all tests performed. In turn, the process variables dimensioned in this study were the rotation speeds of the rock feed screw in the mill and that of the air classifier, in such a way that the circulation flow in the mill used stabilized at a value between 300 and 350 kg / h.

[0103] The three processing conditions indicated in Table 6 below were evaluated. Each one aimed to produce rock powder according to the defined grinding criterion, resulting in the respective productivities indicated in the "product flow rate" column.

[0104] Table 6: Process and productivity parameters for each test condition.

[0105] Throughout each test, samples were taken of the powder produced. with the objective of evaluating the stabilization of the process and the respective grinding requirement. As a reference, Table 7 below shows the particle size distribution results of the final product (“Filter”), collected and analyzed during each test and which meet the defined criteria. The same table also shows the moisture content of each sample and the total production for the day.

[0106] Table 7: Particle size distribution, moisture content, and total production for each day (batch) of testing.

[0107] These results indicate that the material from Lot #3 (d99 ≤ 45 pm) satisfactorily reproduces the particle size distribution results of the reference lot used in premix production. Furthermore, the results obtained in Lot #1 (d99 ≤ 20 pm) and Lot #2 (d99 ≤ 10 pm) significantly reduced the particle size distribution profile of the reference lot.

[0108] After the tests were carried out, the set of results showed that the comminution obtained in Batch #2 was consistent with the grinding conditions of system, still within feasible processing parameters.

[0109] Those skilled in the art will appreciate the knowledge presented here and will be able to reproduce the invention in the forms presented and in other variants and alternatives, covered by the scope of the following claims.

Claims

Claims 1. A preparation of rock particles characterized by comprising a content equal to or greater than 95% by weight of rock particles, wherein 10% to 50% of the particles (d10 to d50) are in the granulometric range of 10 to 1000 nanometers (nm), wherein said rock is basaltic rock, plutonic rock or combinations thereof.

2. Rock particle preparation according to claim 1, characterized in that said rock is basaltic rock.

3. Prepared according to claim 1 characterized in that 50% to 99% of the particles (d50 to d99) are in the particle size range of 403 to 19426 nanometers (nm).

4. Prepared according to claim 1, characterized in that 90% to 99% of the particles (d90 to d99) are in the particle size range of 5573 to 19426 nanometers (nm).

5. Prepared according to any one of claims 1 to 4, characterized by the following particle size distribution profile: d10: between 132 and 153 nm; d50: between 403 and 516 nm; and d90: between 5573 and 7986 nm.

6. Prepared according to any one of claims 1 to 5, characterized by a specific surface area of ​​0.5 to 150 m². 2 / g.

7. Use of the preparation as defined in any one of claims 1 to 6, characterized by being for obtaining other preparations of particles or nanoparticles with adjusted rheological properties, adjusted degrees of packing or void fractions, adjusted flowability of the final preparation, or for the preparation of: stable colloidal compositions; doping of steels, metallic and non-metallic alloys, ceramics and / or polymers; composite materials, electronic components, battery cells, energy storage systems, piezoelectric sensors and actuators, solar panels; glasses, glass-ceramics, transparent and translucent materials; catalysts.

8. Process for obtaining rock particles characterized by understand the steps of: - feeding rock particles to a comminuting machine selected from: high-energy mill, ball mill and steam mill', - Adjust the selected comminution conditions from among: - In a high-energy mill: suspend particles to be comminuted in a liquid, at a concentration between 1% and 90% w / w, and stabilize the suspension until a stable colloidal suspension is obtained; place the suspension and grinding spheres with a diameter selected between 5 µm and 1.3 mm in the grinding chamber; adjust the mill rotation speed between 500 and 4500 rpm; and grind the particles at a temperature below 60 °C; or - In a jet mill with superheated fluid or a Steammill, feed particles smaller than 40 micrometers; adjust the air classifier rotation between 1,000 and 25,000 rpm; adjust the compressed steam pressure between 10 and 100 bar and the temperature between 230 and 360 °C; and - comminute the particles until the desired particle size distribution is obtained.

9. Process according to claim 8 characterized in that said stabilization of the colloidal suspension is done by: adjusting the pH of the polar liquid medium to the range between 2 and 13, and optionally adding surfactants; or adding surfactants to the supporting liquid medium.

10. Process according to claim 8 characterized by further comprising a pre-comminution step of the rock particles before the feeding step to the comminution equipment, said pre-comminution being conducted until an average particle size of less than 40 micrometers is reached.

11. Process according to claim 10 characterized in that said pre-comminution is carried out in a ball mill, disc mill or high-energy mill, preferably by hammering in a ball or pellet mill.

12. Process according to any one of claims 8 to 11 characterized by comprising the steps of: - feeding a high-energy mill with rock particles, in which the These particles are micrometric in size; - feed the mill with a liquid and adjust the pH to the range between 5 and 10; - feeding the aforementioned mill with spheres with a diameter selected between 50 µm and 400 µm; - Adjust the mill's rotation speed between 2000 and 4000 rpm; and - Grind the particles at a temperature below 60 °C until the desired particle size distribution is obtained.

13. Process according to claim 12 characterized in that the high-energy mill is of the agitated type and said spheres are selected from: Zirconia, Silicon carbide, alumina, said spheres being optionally stabilized with yttria or Niobium Pentoxide, or combinations thereof.

14. Process according to claim 8 characterized by the superheated temperature jet mill or Steammill being adjusted with the following parameters: air classifier rotation at 20,000 rpm; compressed steam pressure at 50 bar; and superheated fluid temperature at 280 °C.

15. Product characterized by comprising the preparation of particles, as defined in any one of claims 1 to 6, incorporated into a material selected from metal, non-metal, ceramic, polymer, glass, glass-ceramics or combinations thereof, preferably wherein the product is a stable colloidal composition; steels, metallic alloys, non-metallic alloys, composite materials, electronic components, battery cells, energy storage systems, piezoelectric sensors and actuators, solar panels; transparent and translucent materials; catalysts.

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