Classifications

• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B7/00—Hydraulic cements
  • C04B7/345—Hydraulic cements not provided for in one of the groups C04B7/02 - C04B7/34
  • C04B7/3453—Belite cements, e.g. self-disintegrating cements based on dicalciumsilicate
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B7/00—Hydraulic cements
  • C04B7/345—Hydraulic cements not provided for in one of the groups C04B7/02 - C04B7/34
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
  • C04B2111/00034—Physico-chemical characteristics of the mixtures
  • C04B2111/00181—Mixtures specially adapted for three-dimensional printing (3DP), stereo-lithography or prototyping
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
  • C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
  • C04B2111/00836—Uses not provided for elsewhere in C04B2111/00 for medical or dental applications
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
  • Y02P40/00—Technologies relating to the processing of minerals
  • Y02P40/10—Production of cement, e.g. improving or optimising the production methods; Cement grinding

Definitions

• the present invention relates to a nanoclinker powder having a belite crystalline phase and optionally an alite crystalline phase, a method for its preparation, its use in a cement material and its application in, e.g., construction and building, 3D printing and orthodontics.
• nanomaterials or nano-engineered materials are included in conventional cementitious materials, cement and concrete.
• US 2007/0228612 A1 discloses preparing blast-resistant concrete by incorporating, e.g., micro and nano fibers into conventional concrete.
• US 201 1/05641 1 A1 discloses additives to produce cement for oil-well applications including a hydrolysable organosilane and nanoscale particles (preferably Si0 2 nanoparticles).
• Dicalcium silicate (2Ca0 Si0 2 also referred to as belite or as C 2 S) and tricalcium silicate (3Ca0 Si0 2 also referred to as alite or as C 3 S) are the key components of clinker, which is the main constituent of cement and concrete.
• Belite (C 2 S) and alite (C 3 S) phases are also referred to as hydraulically active phases, as they contribute to the hydraulic properties of cementitious materials and are among the major components of conventional cement used for construction and building, including Ordinary Portland Cement, Rapid Hardening Cement, Low Heat Cement, Sulfate Resisting Cement, White Cement, Portland Pozzolana Cement, Hydrophobic Cement, Colored Cement, Waterproof Portland Cement and other.
• nanoclinker as a nanosized additive.
• engineering nanoclinker components having belite (C 2 S) and optionally alite (C 3 S) phases, with controlled characteristics, e.g. controlled size and crystallinity, which may positively influence the properties of the products to which they are added.
• US 8,409,344 describes methods to produce clinker phases, with at least one oxide exhibiting particle size of less than about 600nm.
• the methods presented are mostly based on liquid chemistry approaches; they involve using nitric acid, urea and other chemicals in addition to clay, limestone and other minerals.
• SEM Scanning Electron Microscopy
• the produced cementitious particles are primarily micron-sized and exhibit irregular shape.
• the final material is reported to contain 58.3% belite and up to 100% of other phases including Ca(OH) 2 , CaO, Si0 2 , and CaO-Si0 2 . Overall, the reported methodology does not result in controlled manufacture of nanosized cementitious phases.
• Yun-Peng Gao et al. (Y.-P. Gao, W.-Q. Dong, G. Li and R.-P. Liu, "Influence of Pressure on the Annealing Process of /?-Ca 2 Si0 4 (C 2 S) in Portland Cement," Chinese Physics Letters, vol. 35, no. 3, p. 036103, 2018) studied claims on the influence of pressure on the annealing process of b-belite in the formation of nano-sized belite particles after annealing Portland cement at high pressure.
• the methodology described aims to identify the effect of pressure on belite, without presenting a manner in which belite nanoparticles of controlled size, shape and crystal structure can be manufactured.
• X-Ray Diffraction results disclosed therein show the presence of significant amounts of silicon dioxide and calcium oxide in the final product.
• a nanoclinker powder comprising a belite (C 2 S) crystalline phase, and optionally comprising an alite (C 3 S) crystalline phase, can be obtained having a particle size range of 2-500 nm as determined by Transmission Electron Microcopy (TEM), comprising nanobelite (C 2 S) particles and, if present, nanoalite (C 3 S) particles, and comprising 0-1 wt.% of CaO and 0-25 wt.% of CaC0 3 based on the total weight of crystalline phases in the nanoclinker powder as determined by powder X-ray diffraction.
• TEM Transmission Electron Microcopy
• such nanoclinker powders can be obtained by a flame spray pyrolysis (FSP) method and, more in particular, in a single step.
• FSP flame spray pyrolysis
• FSP technology has been used extensively for the production of metal oxide nanoparticles in a scalable manner for several applications, including ceramics, construction materials and calcium phosphate cements for dental applications.
• Halim et al. (S. Halim, T. Brunner, R. Grass, M. Bohner and S. W.J., "Preparation of an ultra-fast binding cement from calcium silicate-based mixed oxide nanoparticles," Nanotechnology, vol. 18, 2007) describe the preparation of a nanoparticulate powder using FSP technology, wherein the reported composition of the Portland cement used for the preparation of the precursor contained elements typically found in clinker (68% CaO, 22% Si0 2 , 5.8% Al 2 0 3 , 2.6% Fe 2 0 3 and 1 .5% MgO).
• the dispersion and combustion of the metal containing precursor yielded slightly sintered nanoparticles of 20-50 nm primary particle size, the nanoparticles appear to exhibit significantly low crystallinity. Furthermore, no presence of C 2 S nor C 3 S was observed through X-Ray Diffraction (XRD) analysis and a separate calcination procedure up to 1000 °C was required to obtain the crystalline phases associated with clinker (i.e. C 3 S or C 2 S). The produced material, when mixed with water, was also found to be mechanically weaker than Portland cement. Overall, the reported methodology does not result in the manufacture of nanoclinker comprising belite or alite crystalline phases with FSP technology in a single step procedure.
• Betancur-Granados et al. N. Betancur-Granados, J. C. Restrepo, J. I. Tobon and O. J. Restrepo-Baena, "Dicalcium silicate (2Ca0 Si0 2 ) synthesized through Flame Spray Pyrolysis and Solution Combustion Synthesis methods (CB-6:IL10)," Ceramics International, 2018) describe the use of FSP technology to synthesize directly dicalcium silicate (C 2 S, belite), using silica and calcium precursors in a flame spray system to synthesize allotropic forms of C 2 S.
• the presented methodology leads to partial formation of belite phases, no evidence of control over specific allotropes is provided; instead potentially undesirable phases (such as calcite and calcium oxide) appear in the final product in significant amounts along with belite.
• nanoclinker product and a method to produce a nanoclinker comprising belite, and optionally alite, crystalline phases in a controlled and scalable manner.
• the instant invention provides a nanoclinker powder having a belite (C 2 S), and optionally alite (C 3 S), crystalline phase as determined by powder X-ray diffraction, said nanoclinker powder
• TEM Transmission Electron Microcopy
• Such nanoclinker powder has been found to be obtainable by a flame spray pyrolysis (FSP) method.
• FSP flame spray pyrolysis
• it may be obtained in a single step, whereby the particle size and composition of the powder is obtained in a controlled, scalable and reproducible manner.
• the instant invention further provides a method for making such a nanoclinker powder by flame spray pyrolysis (FSP) comprising:
• step b) spraying and dispersing the flammable solution provided in step a) by oxygen to provide an aerosol of the calcium and silicon precursors onto a pyrolysis flame;
• step d) combusting the aerosol provided in step b) by the pyrolysis flame surrounded by the additional oxygen, thereby pyrolyzing the calcium and silicon precursors to form a nanoclinker powder comprising a belite crystalline phase and, optionally, an alite crystalline phase;
• step d) collecting the nanoclinker powder formed in step d) on a filter.
• Figure 1 Characterization of Material of Example #1 : (A) X-ray diffractogram; (B) and
• Figure 2 Characterization of Material #2: (A) X-ray diffractogram; (B), (C) and (D) Bright-field TEM images; (E) SAED of area of image (D).
• Figure 3 Characterization of Material of Example #3: (A) X-ray diffractogram; (B) Bright-field TEM image; (C) Ca Electron Energy Loss Spectroscopy (EELS) mapping for TEM image (B); (D) Si EELS mapping for TEM image (B); (E) Bright-field TEM image; (F) High resolution TEM image showing crystal lattice; (G) SAED of area of image (E).
• Figure 4 Characterization of Material of Example #4: (A) X-ray diffractogram; (B) and (C) Bright-field TEM images.
• Figure 5 Characterization of Material of Example #5: (A) X-ray diffractogram; (B) and (C) Bright-field TEM images.
• Figure 6 Characterization of Material of Example #6: (A) X-ray diffractogram; (B) and (C) Bright-field TEM images; (D) Ca EELS mapping for TEM image (C); (E) Si EELS mapping for TEM image (C); (F) and (G) High resolution TEM images showing crystal lattices.
• Figure 7 Characterization of Material of Example #7: (A) X-ray diffractogram; (B) and (C) Bright-field TEM images.
• Figure 8 Characterization of Material of Example #8: (A) X-ray diffractogram; (B) and (C) Bright-field TEM images.
• Figure 9 Characterization of Material of Example #10: (A) and (B) Bright-field TEM images; (C) Energy-Dispersive X-Ray Spectroscopy (EDS) spectrum showing elemental analysis - copper and carbon peaks originate from the sample support (copper grid with carbon continuous thin film).
• EDS Energy-Dispersive X-Ray Spectroscopy
• Figure 10 Characterization of Material of Example #11 : A) X-ray diffractogram; (B) Bright-field TEM image; (C) High resolution TEM image showing crystal lattices; (D) SAED of area of image (B); (E) Scanning TEM image; (F) Ca Energy-Dispersive X-Ray Spectroscopy (EDS) mapping for Scanning TEM image (E); (G) Si EDS mapping for Scanning TEM image
• E Al EDS mapping for Scanning TEM image
• E Mg EDS mapping for Scanning TEM image
• E K
• Figure 1 1 design of an FSP reactor suitable for a process as described herein.
• a nanoclinker powder as described herein comprises a belite (C 2 S) crystalline phase and may optionally comprise an alite (C 3 S) crystalline phase.
• Nanoclinker crystalline phases are determined by powder X-ray diffraction (XRD). Methods of determining crystalline phases by powder X-ray diffraction are known in the art. Reference is made to, e.g.,“X-ray powder diffraction applied to cement” by Ruben Snellings, Chapter 4 in “A Practical Guide to Microstructural Analysis of Cementitious Materials” (ed. Karen Scrivener, Ruben Snellings, and Barbara Lothenbach, CRC Press 2016).
• measurements may be performed on powders immediately upon preparation with an X-Ray diffractometer (such as a Bruker D8 Advance) at, e.g., a 2-theta range of 10 to 75 degrees, at 40kV and 40mA, using a Cu-Ka source (with wavelength of emission, l equal to 1.54056 A).
• Quantification of crystalline and other phases in the powder may be performed with, e.g., TOPAS 5 software, based on Rietveld method; all XRD Rietveld quantification results may be presented as weight percentage with respect to the total weight of crystalline phases.
• the belite crystalline phase (C 2 S) may represent 1-100 wt. % of the total weight of crystalline phases in the nanoclinker powder as determined by powder X-ray diffraction, in particular may represent 25-100 wt.%, more in particular 35-99 wt.% and more in particular 50-95 wt.%. In several embodiments, the belite crystalline phase (C 2 S) may represent 75-100 wt.%, in particular 90-100 wt.% and yet more in particular 100 wt.% of the total weight of crystalline phases in the nanoclinker powder as determined by powder X-ray diffraction.
• the alite crystalline phase (C 3 S) may represent 1-55 wt. % of the total weight of crystalline phases in the nanoclinker powder as determined by powder X-ray diffraction, in particular 5-52 wt.%, and more in particular 8-47 wt.%. In several embodiments, the alite crystalline phase (C 3 S) may represent 25-55 wt.%, in particular 40-55 wt.% and more in particular 45-55 wt.% of the total weight of crystalline phases in the nanoclinker powder as determined by powder X-ray diffraction.
• belite and alite crystalline phases may include calcium oxide, or calcite (calcium carbonate), or a combination of the afore mentioned crystalline phases.
• the crystalline phases of the nanoclinker powder may only include belite crystalline phases or belite and alite crystalline phases.
• the remaining crystalline phases up to 100wt.% include alite crystalline phases and may further include calcium oxide, calcite, or a combination of the aforementioned, but may preferably only include alite crystalline phases.
• alite crystalline phases are present in a percentage weight amount as described herein, the remaining crystalline phases up to 100 wt.% include belite crystalline phases and may further include calcium oxide, calcite, or a combination of the aforementioned, but may preferably only include belite crystalline phases.
• the belite crystalline phase (C 2 S) may represent 45-99 wt.% and the alite crystalline phase (C 3 S) may represent 1 -55 wt.% of the total weight of crystalline phases in the nanoclinker powder as determined by powder X-ray diffraction.
• the belite crystalline phase (C 2 S) may represent 75-100 wt.% and the alite crystalline phase (C 3 S) may represent 0-25 wt.% of the total weight of crystalline phases in the nanoclinker powder as determined by powder X-ray diffraction.
• the belite crystalline phase (C 2 S) may comprise crystal phases selected from a-C 2 S, a’-C 2 S, -C 2 S and y-C 2 S, in particular may comprise crystal phases selected from a’-C 2 S and -C 2 S.
• a nanoclinker as described herein may comprise a belite crystalline phase a’-C 2 S and a belite crystalline phase selected from a-C 2 S and/or -C 2 S, wherein the weight ratio of the crystalline phase a’-C 2 S to the crystalline phase selected from a-C 2 S and/or -C 2 S is in the range of 99:1 to 1 :99.
• the alite crystalline phase (C 3 S) may comprise crystal phases selected from, e.g., M1 -C 3 S and M3-C 3 S.
• a nanoclinker as described herein may comprise an alite crystalline phase M3-C 3 S and an alite crystalline phase M1 -C 3 S, wherein the weight ratio of the crystalline phase M3-C 3 S to the crystalline phase M1 -C 3 S is in the range of 56:1 to 1 :1.
• the nature and weight ratios of the different belite and alite crystal phases can be determined by powder XRD as described above.
• the experimental XRD spectra for each material can be analyzed, based on Rietveld method using TOPAS 5 software allowing quantitative identification of the crystal phases and their weight ratios in each material.
• a nanoclinker powder as described herein generally has a particle size range of 2- 500 nm, as determined by Transmission Electron Microcopy (TEM) by methods known in the art. For instance, reference is made to“Electron Microscopy” by Karen Scrivener, Amelie Bazzoni, Berta Mota and John E. Rossen, Chapter 8 in“A Practical Guide to Microstructural Analysis of Cementitious Materials” (ed. Karen Scrivener, Ruben Snellings, and Barbara Lothenbach, CRC Press 2016).
• TEM Transmission Electron Microcopy
• the TEM analysis may be performed with a microscope (such as a FEI CM20 microscope, or a Thermo Fischer Scientific Talos F200i S/TEM); which may be equipped with an energy filter (such as a Gatan GIF200 energy filter), to allow for Electron Energy Loss Spectroscopy (EELS) studies and qualitative elemental mapping, and may be equipped with a suitable detector to perform Energy-Dispersive X-Ray Spectroscopy (EDS) studies and qualitative elemental mapping (such as a Bruker X-flash 6/100 windowless EDS detector).
• a microscope such as a FEI CM20 microscope, or a Thermo Fischer Scientific Talos F200i S/TEM
• an energy filter such as a Gatan GIF200 energy filter
• EDS Energy-Dispersive X-Ray Spectroscopy
• qualitative elemental mapping such as a Bruker X-flash 6/100 windowless EDS detector.
• a particle size range of 2-500 nm means that particles of the nanoclinker powder may have a size from 2 nm to 500 nm, independently of what the particle size distribution or the average particle size of the nanoclinker powder may be.
• the particle size range may be of 5-250 nm, in particular of 10-200 nm, and more in particular of 15-100 nm as determined by TEM.
• the particle size distribution of nanoclinker powders as described herein with the same or similar particle size ranges may vary. For instance, it may be a Gaussian particle size distribution or a different type of distribution. Accordingly, the average particle size of nanoclinker powders as described herein with the same or similar particle size ranges may also vary significantly.
• a nanoclinker powder as described herein generally comprises nanobelite (C 2 S) particles and may optionally comprise nanoalite (C 3 S) particles and/or nanobelite and nanoalite (C 2 S-C 3 S) particles.
• C 2 S-C 3 S particles may comprise neck-sintered C 2 S and C 3 S particles as determined by TEM. The presence of such particles can be simply visualized in the TEM images, e.g., obtained in the same way as for the determination of the particle size range as described above.
• Nanobelite particles may comprise belite crystallites and, if present, nanoalite particles may comprise alite crystallites. Nanobelite or nanoalite particles may also comprise a combination of belite and alite crystallites. Nanobelite or nanoalite particles may also respectively consist of belite or alite crystallites, or may even consist of a single belite or alite crystallite. Nanobelite or nanoalite particles may also respectively comprise belite or alite crystallites combined with other silicon or calcium oxides.
• Said crystallites may generally have an average crystallite size of 5-50 nm as determined by powder X-ray diffraction, in particular of 10-35 nm, more in particular 12-33 nm, yet more in particular 15-30 nm.
• the average crystallite size may be determined by powder X-ray diffraction by methods known in the art. For instance, the Scherrer equation may be used as described in“Elements of X-Ray Diffraction (3 Edition)” by B.D. Cullity and S.R. Stock (Pearson Education Limited, 2014). Powder X-ray diffraction measurements may be collected using the apparatus and software indicated above for the determination of the crystalline phase.
• nanoclinker powders with a particle size range and, optionally, an average crystallite size as indicated above, and comprising belite and optionally alite crystalline phases as also indicated above, can have a positive impact on cement hydration rate and mechanical performance when used as additives in conventional cement.
• such nanoclinker powder may be regarded to combine the advantages of nanoparticle additives with those of belite and alite additives.
• a nanoclinker powder as described herein comprises 0-1 wt.% of CaO and 0-25 wt.% of CaC0 3 based on the total weight of crystalline phases in the nanoclinker powder as determined by powder X-ray diffraction.
• the amount of CaO and CaC0 3 may be determined by powder X-ray diffraction as described above for the determination of the belite and alite crystalline phases.
• the amount of CaO may be 0-0.5 wt.%, in particular 0-0.1 wt.%.
• the amount of CaC0 3 may be 0-15 wt.%, in particular 0-1 1 wt.%.
• a nanoclinker powder particularly has an alite (C 3 S) crystalline phase and comprises 0-0.1 wt.% of CaO and 0-1 1 wt.% of CaC0 3 , based on the total weight of crystalline phases in the nanoclinker powder.
• Nanoclinkers as described herein are generally well formed, highly crystalline, as are rich in belite and, if present, alite crystalline phases as indicated above, and generally have low amounts of impurities generally present in clinker compositions, such as CaO and CaC0 3 as also described above. Such nanoclinkers may advantageously provide cement products with superior hydrating and mechanical properties, in particular superior compressive strength after hardening.
• Nanoclinker powders as described herein may be further enriched with one or more heteroatoms.
• the heteroatoms may be metal or non-metal atoms, other than calcium and silicon, which may be incorporated in the nanoclinker to provide specific properties to the nanoclinker, e.g. on clinker hydration reactivity.
• heteroatoms such as aluminum, magnesium, iron, sulphur, phosphorus, sodium, potassium, chlorine, fluorine, chromium, zinc and boron, may be preferred.
• Aluminum and/or magnesium may be particularly preferred heteroatoms.
• heteroatom- based crystal phases may be present.
• the heteroatom is aluminum heteroatom-based crystal phases may be present in the form of, e.g., tricalcium aluminate (C 3 A), having the chemical formula Ca 3 AI 2 0 6 .
• a nanoclinker powder as described herein may further have a tricalcium aluminate (C 3 A) crystalline phase, which may be found in, e.g., the cubic, orthorhombic or monoclinic allotrope.
• a nanoclinker powder as described herein may comprise 0.1 to 5 wt.% of the total weight of crystalline phases in the nanoclinker powder as determined by powder X-ray diffraction, in particular from 0.25 to 2.5 wt.% more in particular from 0.5 to 1.5 wt.%.
• the remaining crystalline phases up to 100 wt.% include alite crystalline phases and further include heteroatom-based crystal phases and may optionally include calcium oxide and/or, calcite crystalline phases.
• the remaining crystalline phases up to 100 wt.% include belite crystalline phases and further include heteroatom-based crystal phases and may optionally include calcium oxide and/or calcite crystalline phases.
• a nanoclinker powder as described herein may comprise nano tricalcium aluminate (C 3 A) particles, nanoalite and tricalcium aluminate (C 3 S- C 3 A) particles, nanobelite and tricalcium aluminate (C 2 S-C 3 A) particles, and/or nanobelite nanoalite and tricalcium aluminate (C 2 S-C 3 S-C 3 A) particles.
• Heteroatom structures including, e.g., aluminum or magnesium heteroatoms, may additionally or alternatively be present in a nanocliker powder as described herein with the heteroatoms in the form of embedded atoms within the structure of crystalline phases, such as belite or alite.
• a nanoclinker powder as described herein may comprise 0.1 to 2.0 wt.% of embeded aluminum with respect to the total atomic mass of the particles in the nanoclinker powder as determined by Scanning-TEM EDS analysis, in particular from 0.15 to 1.0 wt.% more in particular from 0.25 to 0.65 wt.%.
• a nanoclinker powder as described herein may comprise 0.1 to 1.0 wt.% of embedded magnesium with respect to the total atomic mass of the particles in the nanoclinker powder as determined by Scanning-TEM EDS analysis, in particular from 0.10 to 0.95 wt.% more in particular from 0.25 to 0.55 wt.%.
• the present invention further relates to a method for making a nanoclinker powder as described herein by flame spray pyrolysis (FSP).
• FSP flame spray pyrolysis
• step b) spraying and dispersing the flammable solution provided in step a) by oxygen onto a pyrolysis flame, to provide an aerosol of the calcium and silicon precursors onto the pyrolysis flame;
• step d) combusting the aerosol provided in step b) by the pyrolysis flame surrounded by the additional oxygen, thereby pyrolyzing the calcium and silicon precursors to form a nanoclinker powder comprising a belite crystalline phase and, optionally, an alite crystalline phase;
• step e) collecting the nanoclinker powder formed in step d) on a filter.
• Calcium and silicon precursors suitable for a method described herein may typically be soluble in a flammable solvent to form a flammable solution and, optionally, themselves may also be combustible.
• a calcium precursor suitable for a method as described herein may be selected from, e.g., calcium 2-ethylhexanoate, calcium nitrate, calcium acetylacetonate, calcium acetate and calcium carbonate.
• the use of calcium 2- ethylhexanoate may be preferred since it provides high combustion enthalpy.
• a silicon precursor suitable for a method as described herein may be selected from, e.g., hexamethyldisiloxane, octedecyltrimethoxysilane and triethoxymethylsilane.
• the use of hexamethyldisiloxane may be preferred since it provides high combustion enthalpy.
• a flammable solvent is a solvent which will combust in a pyrolysis flame under FSP conditions.
• a flammable solvent suitable for a method as described herein may be selected from, e.g., tetrahydrofuran, 2-methyltetrahydrofuran, xylene, methanol, ethanol, dichloromethane, cyclopentyl methyl ether, and acetonitrile.
• tetrahydrofuran may be preferred since may contribute to the solubility of the calcium and silicon precursors.
• Dissolving a calcium precursor and a silicon precursor in a flammable solvent to provide a flammable solution of the calcium and silicon precursors may be done by any methods known in the art. For instance, addition of calcium precursor and silicon precursor at the desired concentrations in the flammable solvent, may be performed under mild heating, e.g., at 60°C and stirring with a magnetic stirrer for, e.g., 60 minutes.
• the atomic ratio of calcium to silicon in the flammable solution of the calcium and silicon precursors of step a) may be in the range of 2.0:1 .0 to 3.2: 1.0, or of 2.9:1 to 3.1 :1. Such ratios may advantageously contribute to controlling of the C 2 S/C 3 S phase-weight ratios in the final powder material.
• the flammable solution may have a total precursor concentration of 0.01-2 M, in particular 0.1-1 M, and more in particular, 0.25-0.75 M, e.g. about 0.45 M or about 0.5 M, based on the total mols of calcium precursor and silicon precursor per liter of flammable solution. Precursor concentrations in these ranges may contribute to the crystallinity and purity of belite and, optionally, alite phases.
• step a) may further comprise dissolving a heteroatom precursor, alongside the calcium precursor and the silicon precursor in the flammable solvent to provide the flammable solution of the calcium and silicon precursors further comprising the heteroatom precursor.
• a heteroatom is a metal or non-metal atom, other than calcium and silicon, which may be incorporated in the manufacture of the nanoclinker to provide specific properties to the nanoclinker, e.g. on clinker hydration reactivity.
• the heteroatom may be selected from aluminum, magnesium, iron, sulphur, phosphorus, sodium, potassium, chlorine, fluorine, chromium, zinc and boron, and aluminum and/or magnesium may be preferred.
• a heteroatom such as aluminum and/or magnesium may be introduced in a method as described herein for the preparation of nanoclinker powders which can be doped by simply adding a precursor of the heteroatom precursor in step a) of the method to provide the precursor solution.
• the heteroatom precursor may be an aluminum precursor (such as aluminum fr/ ' -sec-butoxide) and/or a magnesium precursor (such as b/ ' s-cyclopentadienyl magnesium and/or magnesium acetylacetonate).
• the presence of the heteroatom does not detrimentally affect the execution of the method and in particular allows obtaining nanoclinker powders with belite and optionally alite crystalline phases, without detrimentally affecting the amount of the crystalline phases or crystal structure thereof, maintaining controllability of a method as described herein and even increasing its versatility.
• the amount of heteroatom precursor may be from 0.1% to 5 % based on the total weight of precursor compounds.
• the flammable solution provided in step a) is sprayed and dispersed by oxygen onto a pyrolysis flame, to provide an aerosol of the calcium and silicon precursors onto the pyrolysis flame (step b).
• the flow rate of the flammable solution i.e. the precursor in liquid form, also referred to herein as liquid precursor, precursor solution or flammable precursor solution
• the oxygen (0 2 ) flow rate may be in the range of 3-12 L/min, in particular 5-10 L/min, e.g. of about 5, about 7 or about 10 L/min.
• Such flow rates may advantageously contribute to the purity of the nanoclinker powder.
• the pyrolysis flame may be generally ignited by a pilot flame.
• the pilot flame may be fueled by gases selected from, e.g., methane (CH 4 ), oxygen (0 2 ) and mixtures thereof.
• This fuel is also referred to as supporting fuel, which may preferably comprise a mixture of supporting CH 4 and supporting 0 2 .
• the flow rate of said supporting oxygen and/or supporting methane may be in the range of 2-10 L/min, e.g. about 5 or about 6 L/min for supporting oxygen and about 2.5, about 4, about 6 or about 7 L/min for supporting methane.
• the flammable precursor solution constitutes the fuel which is premixed with dispersion 0 2 and ignited by the pilot flame.
• step c additional oxygen is supplied as a sheath surrounding the pyrolysis flame (step c). It has been found that supplying a sheath of oxygen surrounding the pyrolysis flame contributes to the crystallinity and purity of the nanoclinker powder obtained. In particular, it has been found that the amount of belite, and if present alite, crystalline phases is higher when using an oxygen sheath than in absence of such a sheath. Furthermore, the presence of such a 0 2 sheath has been found to contribute to the purity of nanoclinker powders as described herein and to the control of the formation of belite and alite crystalline phases.
• the flow rate of oxygen supplied as a sheath may be in the range of 1-20 L/min, in particular 2-10 L/min, more in particular 2.5-7.5 L/min, e.g. about 5 L/min.
• Other gases may be supplied together with oxygen to form the sheath.
• a mixture of nitrogen and oxygen may be supplied as a sheath, whereby the nitrogen may be supplied at a flow rate of 5-20 L/min, in particular 7-15 L/min, e.g. about 10 L/min.
• the flow rate of additional oxygen provided in step c) as a sheath surrounding the pyrolysis flame is such that the normalized fuel to oxidant ratio“phi” (F) is in the range of 0.45 to 0.65, in particular of about 0.5.
• the normalized fuel to oxidant ratio“phi” (F) may be determined according to the book“An Introduction to Combustion: Concepts and Applications S.R. Turns in” (3 rd ed.; McGraw-Hill: New York, 2012), as follows:
• the fuel components are the premixed precursor solution and the fuel gas (e.g. CH 4 ), and the oxidant components the dispersion 0 2 gas, the supporting 0 2 gas, and the sheath 0 2 gas.
• the fuel gas e.g. CH 4
• a normalized [fuel to oxidant] ratio“phi” (F) within the ranges described herein may be regarded as fuel-lean or oxygen rich. Such ratios result in an accelerated combustion by the excess 0 2 into the reactor which have been found to contribute to the purity and crystallinity of belite and, if present, alite. In particular may contribute to the formation of nanoalite and to its stabilization through rapid cooling.
• the absence of sheath 0 2 e.g. resulting in increased F values, e.g. above unity (F>1 )
• F fuel-lean or oxygen rich
• the different gases and liquids may be supplied to the burner (FSP-burner) through a nozzle (also referred to as FSP-nozzle).
• the FSP-Nozzle may typically operate under pressure drop in the range of 1-2 bar, preferably of about 1.8 bar.
• an enclosed flame setup comprising a tube surrounding the pyrolysis flame and the oxygen sheath.
• Such set up may favor the formation of the sheath around the pyrolysis flame and allow longer high-temperature residence times of the particles in the flame.
• Such tube may be positioned on top of the FSP-Nozzle, preferably with zero-gap between the tube and the body of the FSP-nozzle.
• such a tube may preferably be a metal or quartz cylinder. If metal is used, a high temperature metal alloy, such as Inconel 601 (INCONEL® nickel-chromium-iron alloy 601 , UNS N06601/W. Nr. 2.4851 ), may be preferred.
• Such a tube may have a length of 30-50 cm, in particular of 35-45 cm, e.g. of about
• step d the combustion of the aerosol provided in step b) by the pyrolysis flame surrounded by additional oxygen, results in the pyrolysis of the calcium and silicon precursors thereby forming a nanoclinker powder comprising a belite crystalline phase and optionally an alite crystalline phase (step d).
• the nanoclinker powder formed in step d) is collected on a filter (step e).
• the filter may generally have a high surface area, e.g. of 500-1200 cm 2 , in particular of 750-1000 m 2 , e.g. of about 900m 2 .
• the filter may be assisted by a vacuum pump.
• High surface areas and/or the presence of a vacuum as indicated above may advantageously favor the collection of the particles.
• the filter may be, e.g., a glass-fiber filter or a metallic grid, which may consist of a metal-felt.
• Metallic filters should be able to sustain temperatures in the range 600-1100 ° C.
• the filter may preferably be made of titanium (e.g. a titanium felt) and/or stainless steel (e.g. a stainless steel felt).
• the distance between the FSP-Nozzle and the filter may be of 40-80 cm, in particular of 50-75 cm, more in particular from 60-70 cm e.g. of about 63 cm, of about 65 cm or of about 67 cm.
• FSP reactors suitable for a method for making a nanoclinker powder as described herein are known in the art.
• an FSP reactor suitable for a method as described herein may typically comprise three parts: an FSP-nozzle (A), an enclosing metallic tube (B) and a particle collection metallic-grid filter (C).
• an FSP reactor with a design as illustrated in Figure 11 may be used.
• a liquid precursor e.g. a flammable solution of the calcium and silicon precursors of step a
• a FSP-Nozzle allows introduction of a supporting CH 4 together with supporting 0 2 and a sheath 0 2 .
• a metal tube B may be positioned on top of the FSP-Nozzle, A, with zero-gap between the tube and the nozzle-body.
• a filter a metallic grid filter in particular, e.g. consisting of a metal-felt assisted by a vacuum pump, collects the particles being formed.
• the sprayed calcium and silicon precursors are combusted in the flame forming particles that may change in size and composition during their flight from the flame to the filter.
• the particles that are collected upstream on the filter where may be rapidly cooled forming a stable powder which may be collected by simple scraping from the filter.
• a method as described herein allows the production of nanoclinker powders of controlled particle size, crystallinity and composition as described above in a single step, without requiring separate calcination or particle diminution steps.
• the use of an oxygen sheath may contribute to the size, crystallinity and purity of the nanoclinker powder as described herein.
• the use of an enclosing metal tube may further contribute to the advantageous properties of a nanoclinker powder obtainable by a method as described herein.
• the instant invention further relates to a nanoclinker powder obtainable by a method as described herein.
• the properties of a nanoclinker powder as described herein also apply to a nanoclinker powder obtainable by a method as described herein.
• the instant invention further relates to a cement material comprising a nanoclinker powder as described herein.
• the nanoclinker powder may be mixed with other constituents typically used in cement production, including but not limited to constituents selected from, e.g., limestone, pozzolan (natural or artificial), metakaolin, blast furnace slag, silica fume, burnt shale, fly ash, electric arc furnace slag, quartz, anhydrite and gypsum.
• the instant invention further relates to the use of a nanoclinker powder as described herein or of a cement material comprising the same, as
• cement products selected from Ordinary Portland Cement (OPC), hydraulic cement and blended hydraulic cement products, rapid hardening cement, low heat cement, sulfate resisting cement, white cement, portland pozzolana cement, hydrophobic cement, colored cement, waterproof portland cement, oil-well cement, self-healing cement and mortars, self-cleaning cement and mortars; and concrete products comprising said cement products;
• OPC Ordinary Portland Cement
• hydraulic cement and blended hydraulic cement products rapid hardening cement, low heat cement, sulfate resisting cement
• white cement portland pozzolana cement
• hydrophobic cement colored cement
• waterproof portland cement oil-well cement
• self-healing cement and mortars self-cleaning cement and mortars
• concrete products comprising said cement products
• a nanoclinker powder as described herein generally has an advantageous impact in the mentioned applications.
• it may provide controlled and rapid hydration of the cement which may lead to a hardened material with mechanical performance equivalent or better to conventional cement in terms of resistance to compressive strength, albeit exhibiting reduced porosity, increased resistance to chloride and sulfate ingress and improved resistance to carbonation due to carbon dioxide gas being diffused through its pore network.
• the present invention is further illustrated by the following examples without being limited thereto or thereby.
• Nanoclinker powders comprising belite and optionally alite and optionally tricalcium aluminate crystalline phases, or combination of the aforementioned crystalline phases as described herein were produced by the following preparation protocols.
• Protocol #1 Production of nano-clinker powder with high content of belite
• Nano-clinker powders were prepared in a single step by FSP and were collected on glass- fiber filter.
• Appropriate calcium precursors including calcium 2-ethylhexanoate, calcium nitrate tetrahydrate, calcium neodecanoate and calcium cyclohexanebutyrate were used, in addition to appropriate silicon precursors, including hexamethyldisiloxane, isopropenyloxy- trimethylsilane and trimethylsilyl-isocyanate.
• Precursors were added in suitable solvent, preferably tetrahydrofuran, 2-methyltetrahydrofuran, dichloromethane, methanol or cyclopentyl methyl ether, to form the precursor solution.
• the total precursor concentration in the solvent ranged from 0.1 to 1.0 M; with a calcium to silicon atom ratio in the range between 2.1 : 1.0 to 2.4: 1.0.
• the precursor solution was fed through the FSP capillary nozzle with a flow rate of 5 or 10 mL/min or any other value in between; dispersed to a fine spray by an oxygen flow rate ranging between 4 to 10 L/min; and combusted, under controlled pressure-drop at the nozzle tip (ranging between 1.5 to 2.0 bar).
• a pilot flame was formed using oxygen and methane. Additionally, a supply of nitrogen (5-10 L/min) and oxygen (2-4 L/min) gases was provided as an outer sheath flow.
• An enclosed flame setup was used with a tube of at least 40 cm length with a burner-to-filter distance between 60 and 65cm.
• Protocol #2 Production of nano-clinker powder with high content of alite
• Nano-clinker powders were prepared in a single step by FSP and were collected on glass- fiber filter.
• Appropriate calcium precursors including calcium 2-ethylhexanoate, calcium nitrate tetrahydrate, calcium neodecanoate and calcium cyclohexanebutyrate were used in addition to appropriate silicon precursors, including hexamethyldisiloxane, isopropenyloxy- trimethylsilane and trimethylsilyl-isocyanate.
• Precursors were dissolved in suitable solvent, preferably tetrahydrofuran, 2-methyltetrahydrofuran, dichloromethane, methanol or cyclopentyl methyl ether, to form the precursor solution.
• the total precursor concentration in solvent was from 0.2 to 0.5 M with a calcium:silicon atom ratio of 2.9: 1.0 to 3.1 :1.0.
• the precursor solution was fed through the FSP capillary nozzle with a flow rate of 3-5 mL/min, dispersed to a fine spray by an oxygen flow rate of 5-8 L/min and combusted, under a 1.5-2.0 bar pressure-drop at the nozzle tip.
• a pilot flame was formed using oxygen and methane.
• Aluminum and magnesium enriched nano-clinker powders were prepared in a single step by FSP and were collected on glass-fiber filter.
• Appropriate calcium precursors including but not limited to calcium 2-ethylhexanoate, calcium nitrate tetrahydrate, calcium neodecanoate and calcium cyclohexanebutyrate were used, in addition to appropriate silicon precursors, including but not limited to hexamethyldisiloxane, isopropenyloxy-trimethylsilane and trimethylsilyl-isocyanate.
• silicon precursors including but not limited to hexamethyldisiloxane, isopropenyloxy-trimethylsilane and trimethylsilyl-isocyanate.
• aluminum fr/ ' -sec-butoxide was used as aluminum precursor
• magnesium-acetylacetonate was used as magnesium precursor.
• Precursors were dissolved in suitable solvent, preferably methanol, tetrahydrofuran, 2- methyltetrahydrofuran, dichloromethane or cyclopentyl methyl ether, to form the precursor solution.
• suitable solvent preferably methanol, tetrahydrofuran, 2- methyltetrahydrofuran, dichloromethane or cyclopentyl methyl ether.
• the total precursor concentration in solvent ranged from 0.1 to 1.0 M, preferably in the range of 0.34 to 0.68 M; with a calcium to silicon atom ratio in the range from 2.1 : 1.0 to 2.4 : 1 .0.
• the heteroatom precursor content preferably ranged from 0.5% to 5% of total atoms of heteroatom per total atoms of calcium and silicon.
• the precursor solution was fed through the FSP capillary nozzle with a flow rate of 5- 10 mL/min; dispersed to a fine spray by oxygen flow ranging from 4 to 10 L/min; and combusted, under controlled pressure-drop at the nozzle tip (preferably ranging between 1.5 to 2.0 bar).
• a supply of nitrogen (1 -10 L/min) and oxygen (1 -4 L/min) gases was provided as an outer sheath flow.
• An enclosed flame setup was used with a tube of at least 40 cm length with a burner-to-filter distance between 60 and 65cm.
• Protocol #1 Materials #1 , 2 & 3 were produced using Protocol #1 , which resulted in nanoclinker powders with high percentage of belite crystalline phases and with no alite.
• Materials #4, 5, 6, 7 & 8 were produced using Protocol #2, which resulted in nanoclinker powders with high-percentage of alite crystalline phases (in the range of 10% up to 50%).
• Material #9 was produced using Protocol #2, without the use of the outer sheath, which resulted in a nanoclinker powder with high amounts of calcium oxide and with particles of sizes beyond 500 nm.
• Calcium precursor was Ca-2-ethylhexanoate or Ca-nitrate tetrahydrate (in examples 1 ,2,3) and Ca-2- ethylhexanoate in examples (4, 5, 6, 7, 8, 9).
• Silicon precursor was hexamethyldisiloxane in all examples.
• Precursor solvent was tetrahydrofuran in all examples.
• Calcium precursor was Ca-2-ethylhexanoate (in examples 10 & 11 ).
• Silicon precursor was hexamethyldisiloxane in all examples.
• Precursor solvent was tetrahydrofuran in all examples.
• nanoclinker specimens prepared with FSP were measured immediately upon synthesis. Measurements were performed with a Bruker D8 Advance at the 2-theta range of 10 to 75 degrees, at 40kV and 40mA, using a Cu-Ka source (with typical wavelength of emission, l equal to 1.54056 A). Quantification of crystalline phases was performed with TOPAS 5 software, based on Rietveld method adapted to nanoparticles; all XRD Rietveld quantification results are presented in Table 2 as weight percentage of total weight of crystalline matter.
• the obtained nanoclinker powders were also analyzed in terms of size, shape and crystalline nature with Transmission Electron Microscopy (TEM). Furthermore, the co-existence of calcium and silicon in nanobelite and nanoalite particles was confirmed through Electron Energy Loss Spectroscopy (EELS). In addition, the co-existence of calcium, silicon, aluminum and magnesium in nanobelite and nanoalite particles was confirmed through Energy Dispersive X-Ray Spectroscopy (EDS).
• TEM Transmission Electron Microscopy
• EELS Electron Energy Loss Spectroscopy
• EDS Energy Dispersive X-Ray Spectroscopy
• TEM, EELS and EDS analyses were performed with a FEI CM20 microscope which was equipped with a Gatan GIF200 energy filter to allow for EELS measurements, in addition to a Thermo Fischer Scientific Talos F200i S/TEM which was equipped with a Bruker X-flash 6/100 windowless EDS detector to allow for EDS measurements.
• Example material #1 was produced using Protocol #1 , utilizing process parameters described in Table 1 a.
• XRD data show that material example #1 contains multiple crystal phases (Figure 1 -A) Rietveld analysis of crystal phases in typical specimens produced as Example #1 exhibit the following crystalline phases: a’ belite (C 2 S) 50.5%, b belite (C 2 S) 43.5%, calcium carbonate (CaC0 3 ) 3.5%, and less than 0.5% of calcium oxide (CaO).
• the nanoparticles size was observed through TEM to range between 2 and 450 nm, as presented in Figures 1 -B to 1 -E.
• Example material #2 was produced using Protocol #1 , utilizing process parameters described in Table 1a.
• XRD data show that material example #2 contains multiple crystal phases (Figure 2-A).
• Rietveld analysis of crystal phases in typical specimens produced as Example #1 exhibit the following crystalline phases: a’ belite (C 2 S) 65.0%, b belite (C 2 S) 24.5%, calcium carbonate (CaC0 3 ) 4.5%, and less than 0.5% of calcium oxide (CaO).
• the nanoparticles size was observed through TEM to range between 5 and 420 nm, as presented in Figures 2-B to 2-E.
• the crystalline nature of the manufactured nanoparticles is exhibited in Figure 2-E, containing the SAED of particles shown in Figure 2-D.
• Example material #3 was produced using Protocol #1 , utilizing process parameters described in Table 1a.
• XRD data for material example #3 indicate a high crystallinity, high purity material, containing 100.0% a’ belite and no other crystalline phases (Figure 3-A).
• the average nanoparticle size of a’ belite is 19 ⁇ 4 nm.
• the nanoparticles size was observed through TEM to range between 2 and 460 nm, as presented in Figures 3-B & 3-E.
• the homogeneous distribution of calcium and silicon in the nanobelite particles is furthermore exhibited in Figures 3-C & 3-D, containing elemental mapping of said elements obtained with Electron Energy Loss Spectroscopy (EELS).
• EELS Electron Energy Loss Spectroscopy
• the crystalline nature of the manufactured nanoparticles is exhibited in Figures 3-F & 3-G, the former containing HRTEM image of nanobelite crystal lattice and the latter containing the SAED of nanobelite particles shown in Figure 3-
• Example material #4 was produced using Protocol #2, utilizing process parameters described in Table 1a.
• XRD data for material example #4 indicate a high crystallinity, high purity material ( Figure 4-A). The content of crystal phases found in specimens produced as example
• material #4 are: alite 9.6% (total), a’ belite 19.2%, a belite 36.2%, and b belite 12.7%.
• the nanoparticles size was observed through TEM to range between 8 and 490 nm, as exhibited in Figures 4-B & 4-C.
• Example material #5 was produced using Protocol #2, utilizing process parameters described in Table 1a.
• XRD data for material example #5 indicate a high crystallinity, high purity material (Figure 5-A).
• the content of crystal phases found in materials produced as Material #5 are: alite M3 33.9%, a’ belite 42.1 %, b belite 12.7%, and other phases.
• the nanoparticles size was observed through TEM to range between 4 and 390 nm, as exhibited in Figures 5-B & 5-C.
• Example material #6 was produced using Protocol #2, utilizing process parameters described in Table 1 a.
• XRD data for material example #6 indicate a high crystallinity, high purity material (Figure 6-A).
• the content of crystal phases found in specimens produced as example materials #6 are: alite M3 44.3% a’ belite 32.5 %, and other phases.
• the nanoparticles size was observed through TEM to range between 4 and 450 nm, as exhibited in Figures 6-B to 6-E.
• the homogeneous distribution of calcium and silicon in the nanobelite & nanoalite particles is furthermore exhibited in Figures 6-D & 6-E, containing elemental mapping of said elements obtained with EELS.
• Figures 6-F & 6-G containing HRTEM image of nanoalite particles.
• Figure 6-F exhibits crystal lattice oriented to show the d-spacing of 0.277nm, which can be attributed to plane 3-0-0 of alite M1 crystal (which corresponds to two-theta of 32.3° in XRD); similarly, Figure 6-G exhibits crystal lattice oriented to show the d-spacing of 0.305nm, which can be attributed to plane 1-0-4-of alite M1 crystal (which corresponds to two-theta of 29.4° in XRD).
• Example material #7 was produced using Protocol #2, utilizing process parameters described in Table 1 a.
• XRD data for material example #7 indicate a high crystallinity, high purity material (Figure 7-A).
• the content of crystal phases found in specimens produced as example material #7 are: M1 alite 22.9%, M3 alite 23.8%, a’ belite 26.8%, and other phases.
• the nanoparticles size was observed through TEM to range between 8 and 420 nm, as presented in Figures 7-B & 7-C.
• Example material #8 was produced using Protocol #2, utilizing process parameters described in Table 1 a.
• XRD data for material example #8 indicate a high crystallinity, high purity material (Figure 8-A).
• the content of crystal phases found in specimens produced as example material #8 are: M1 alite 15.6%, M3 alite 34.9%, a’ belite 29.0%, and other phases.
• the nanoparticles size was observed through TEM to range between 8 and 340 nm, as presented in Figures 8-B & 8-C.
• Example #9 comparativative
• Example material #9 was produced using Protocol #2, utilizing process parameters described in Table 1a.
• the content of crystal phases found in specimens produced as example material #9 are: M1 alite 6%, a’ belite 59%, CaO 6% and other phases.
• the nanoparticles size was observed through TEM to range between 5 and 550 nm.
• Example material #10 was produced using Protocol #3, utilizing process parameters described in Table 1 b.
• XRD data for material example #10 indicate a high crystallinity, high purity material.
• the content of crystal phases found in specimens produced as example material #10 are: total alite 6%, a’ belite 38%, calcite 10% and other phases, as detailed in Table 2b.
• the nanoparticles size was observed through TEM to range between 2 and 350 nm.
• Figure 9 (A) and (B) shows Bright-field TEM images of this product and
• Figure 9(C) shows the corresponding EDS spectrum and the elemental analysis - copper and carbon peaks originate from the sample support (copper grid with carbon continuous thin film).
• Example material #11 was produced using Protocol #3, utilizing process parameters described in Table 1 b.
• XRD data for material example #11 indicate a high crystallinity, high purity material.
• the content of crystal phases found in specimens produced as example material #11 are: total alite 20%, a’ belite 54%, tricalcium aluminate C 3 A (1.5%) and other phases, as detailed in Table 2b.
• XRD data for material example #11 indicate a high crystallinity, high purity material (Figure 10-A). The nanoparticles size was observed through TEM to range between 2 and 350 nm.
• the elemental distribution of said elements is furthermore supported by the EDS analysis shown in Figure 10-K collected from the particle shown in Figure 10-E, the inset in Figure 10-K contains elemental quantification of said elements in atomic mass percentage; copper and carbon peaks originate from the sample support grid (consisting of copper covered with continuous carbon film) and are not included in the quantification. 24
• aterial#4 additionally contains 36.2% of a belite (a-C 2 S) which is included in the total belite.
• aterial#10 additionally contains 24.1% of a belite (a-C 2 S) which is included in the total belite

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