EA040455B1 - COMPOSITE MATERIALS AND BINDING ELEMENTS PRODUCED BY CALCIUM SILICATE CARBONIZATION AND METHODS OF THEIR PRODUCTION AND APPLICATION - Google Patents

Description

Priority claims and related patent applications

This application claims the priority of U.S. Provisional Applications Nos. 62/136201 and 62/136208, both of which were filed on March 20, 2015, the contents of each of which are hereby incorporated by reference.

The field of technology to which the invention belongs

In general, the invention relates to calcium silicate compositions. More specifically, the invention relates to composite materials incorporating novel binders characterized by unique microstructures and chemical compositions, and methods for their preparation and use, for example, as components of various concretes in infrastructure, structures, pavements and landscape architecture.

State of the art

Concrete is the world's most consumed man-made material. Conventional concrete is made by mixing Portland cement, water, and aggregates such as sand and gravel. Portland cement is a synthetic material obtained by firing a mixture of crushed limestone and clay or materials of similar composition in a rotary kiln at a sintering temperature of 1450°C. The production of Portland cement is not only an energy-intensive process, but also a process that releases a significant amount of gas (CO ₂ ) into the atmosphere, causing a greenhouse effect. The cement industry accounts for about 5% of global anthropogenic CO2 emissions. More than 60% of this CO ₂ comes from the chemical decomposition or calcination of limestone.

Increasing efforts are being made to reduce the overall CO2 emissions of the cement industry. According to the proposal of the International Energy Agency in the cement industry, it is necessary to reduce CO2 emissions to the atmosphere from 2.0 Gt (gigatonnes) in 2007 to 1.55 Gt by 2050. This is challenging as cement production is projected to rise from 2.6 to 4.4 Gt over the same period.

To meet this challenge, a revolutionary cement production method has recently been developed that can significantly reduce the energy consumption and CO ₂ emissions of a cement plant. The unique cement is composed of carbonizable calcium silicate compositions and is made from widely available low cost raw materials, and it allows continuous and safe CO ₂ capture while being adaptable and easily adaptable to existing equipment and process requirements, enabling conventional cement producers to easily switch to a new way of production.

In order to improve bond strength and production efficiency, as well as reduce operating costs and carbon dioxide emissions to the atmosphere, it is necessary to develop new binder microstructures and composite materials that match or exceed the physical and performance characteristics of existing concrete mix components.

The essence of the invention

The invention proposes new composite materials and binders, characterized by unique microstructures and chemical compositions, and methods for their production and use, for example, as various components of concrete in infrastructure, structures, road surfaces and landscape architecture. Composite materials and binders disclosed in the invention are obtained by carbonizing suitable calcium silicate materials (eg clinker and cement) which can be obtained from widely available inexpensive raw materials using processes suitable for use in large scale industrial production. The process of the invention is highly adaptable to existing equipment and process conditions and can be readily applied to industrial plants producing conventional Portland cement. The new composite materials disclosed in the invention and the binders present therein can be used in various concretes used in structures, road surfaces and landscape architecture, as well as in infrastructure facilities, with a reduction in the need for equipment, a decrease in energy consumption and a more acceptable carbon dioxide emission into the atmosphere. gas.

In one aspect, the invention relates generally to a composite material obtained by carbonizing calcium silicate with CO2. The composite material includes a plurality of connecting elements of one or more types (microstructures). These types of binders include a binder comprising a core of unreacted carbonizable calcium silicate phase wholly or partially surrounded by a silica-rich crust layer of varying thickness, which is wholly or partially enclosed in a shell of CaCO ₃ particles; a binder comprising a silica core formed by carbonization of a carbonizable calcium silicate phase, wholly or partially surrounded by a silica-rich crust layer of varying thickness, which is wholly or partially enclosed in a shell of CaCO ₃ particles; bonding element comprising a core of silicon dioxide formed as a result of carbonization of a phase having the ability to carbonize

- 1 040455 calcium silicate, fully or partially enclosed in a shell of CaCO ₃ particles; a binder comprising a core of a non-carbonizable phase, completely or partially enclosed in a shell of CaCO ₃ particles; a binding element comprising a multi-phase core consisting of silicon dioxide formed as a result of carbonization of a calcium silicate phase with the ability to carbonize, and partially reacted calcium silicate, where the multi-phase core is completely or partially surrounded by a silica-enriched crust layer of various thicknesses, which is completely or partially enclosed in a shell of CaCO ₃ particles; a binder comprising a multi-phase core consisting of a non-carbonizable phase and partially reacted calcium silicate, where the multi-phase core is completely or partially surrounded by a silica-enriched crust layer of various thicknesses, which is completely or partially enclosed in a shell of CaCO3 particles; a binding element comprising particles of partially reacted calcium silicate without a clearly defined core and a crust layer of silicon dioxide enclosed in a shell of CaCO3 particles; and a bonding element comprising porous particles without a well-defined crust layer of silicon dioxide, enclosed in a shell of particles of CaCO ₃ . Collectively, the plurality of bonding elements form a conjugated bonding matrix that provides bonding strength and fixation of the composite material.

In another aspect, the invention relates generally to a bonding matrix comprising a plurality of bonding elements. The binders are selected from a binder comprising a core of unreacted carbonizable calcium silicate phase, wholly or partially surrounded by a silica-enriched crust layer of varying thickness, wholly or partially enclosed in a shell of CaCO3 particles; a binder comprising a silica core resulting from the carbonization of a carbonizable calcium silicate phase, completely or partially surrounded by a silica-rich crust layer of varying thickness, which is completely or partially enclosed in a shell of CaCO3 particles; a binder comprising a silica core resulting from carbonization of a carbonizable calcium silicate phase, completely or partially enclosed in a shell of CaCO ₃ particles; a binder comprising a core of a non-carbonizable phase completely or partially enclosed in a shell of CaCO ₃ particles; a binding element comprising a multiphase core consisting of silicon dioxide formed as a result of carbonization of a calcium silicate phase with the ability to carbonize, and partially reacted calcium silicate, where the multiphase core is completely or partially surrounded by a silica-enriched crust layer of various thicknesses, which is completely or partially enclosed into a shell of CaCO ₃ particles; a binder comprising a multi-phase core consisting of a non-carbonizable phase and partially reacted calcium silicate, where the multi-phase core is completely or partially surrounded by a silica-enriched crust layer of various thicknesses, which is completely or partially enclosed in a shell of CaCO3 particles; a binding element comprising particles of partially reacted calcium silicate without a distinct core, and a crust layer of silicon dioxide enclosed in a shell of particles of CaCO ₃ ; and a binding element comprising porous particles without a clearly defined crust layer of silicon dioxide, enclosed in a shell of particles of CaCO ₃ .

In yet another aspect, the invention relates generally to a method for producing a composite material comprising the disclosed tie elements.

Brief description of the drawings

The objects and features of the invention may be better understood with reference to the drawings and claims described below. The drawings are not necessarily drawn to scale, in which case it is generally intended to illustrate the principles of the invention. The same numbers in the drawings are used to designate the same parts in all, without exception, different projections.

In FIG. 1(a)-1(f) are schematic representations of examples of connecting members according to exemplary embodiments of the present invention.

In FIG. 2(a)-2(f) are schematic side and sectional views of composite materials according to exemplary embodiments of the present invention, wherein FIG. 2(a) shows 1D oriented fiber-shaped binders in a dilute binder matrix (the binders are not in contact), FIG. 2(b) shows 2D oriented bonding elements in plate form in a diluted bonding matrix (the bonding elements are not in contact), FIG. 2(c) shows 3D oriented bonding elements in plate form in a diluted bonding matrix (the bonding elements are not in contact), FIG. 2(d) depicts randomly oriented bonding elements in plate form in a dilute bonding matrix (bonding elements not in contact), where composite materials include a bonding matrix and filler components such as polymers, metals, inorganic particles, aggregates, and so on, in fig. 2(e) shows a concentrated binder matrix (with a volume content sufficient to

- 2 040455 formation of a percolation network structure) from connecting elements, where the matrix is 3D oriented, in FIG. 2(f) shows a concentrated binder matrix (of sufficient volume to form a percolation network) of randomly oriented binders into which filler components such as polymers, metals, inorganic particles, fillers, and so on can be incorporated.

In FIG. 3 is a diagram of a CO ₂ composite curing chamber in which humidification is provided in accordance with the principles of the invention.

In FIG. 4 is a diagram of a curing chamber using a variety of humidity control methods, and with the ability to control and replenish CO2 using constant flow control or pressure control, in which temperature can be controlled in accordance with the principles of the invention.

In FIG. 5 is a back-scattered electron (BSE) image of reacted cement particles. The image shows with increased brightness the reactive core of the phase of particles with a crust layer of silicon dioxide of various thicknesses and enclosed in a shell of CaCO ₃ (1). The image also shows the phase of inert particles, completely enclosed in a shell of CaCO ₃ (2). The image also shows with increased brightness a multiphase core consisting of reactive phases, and with an average degree of brightness an amorphous phase with a crust layer of silicon dioxide and CaCO ₃ particles (3).

In FIG. Figure 6 shows a microphotograph of the composite in conditional colors, on which various particles of experimental cement 1 are found. One-phase and multi-phase particles with various compositions are visible.

In FIG. Figure 7 shows a microphotograph of the composite in conditional colors, on which various particles of experimental cement 1 are found. One-phase and multi-phase particles with various compositions are visible.

In FIG. Figure 8 shows a microphotograph of the composite in conditional colors, on which various particles of experimental cement 1 are found. One-phase and multi-phase particles with various compositions are visible.

In FIG. 9 is a back-scattered electron (BSE) image of reacted cement particles. The image shows at low brightness the SiO ₂ enriched particle core enclosed in a CaCO ₃ shell (1). The other particle, displayed at high brightness, is the core of the reactive phase, surrounded by a low contrast SiO ₂ crust and completely enclosed by a CaCO 3 shell (2). Another displayed particle is a multi-phase core consisting of a mixed high-contrast reactive phase and an amorphous phase displayed with medium contrast. The core of the particle is surrounded on some surfaces by a low-contrast SiO ₂ crust and partially encased in a CaCO ₃ shell (3).

In FIG. 10 is a back-scattered electron (BSE) image of reacted cement particles. The image shows at high brightness a reactive particle surrounded by a crust layer of various thicknesses of silicon dioxide (1). The particle is enclosed in a shell of CaCO ₃ , on which a crust layer of silicon dioxide is visible. Some particles with high contrast in the image are characterized by a thick silica crust, which is evidence of the intensive reaction (2). If the reaction proceeds to the end, then the particles appear as inert nuclei enclosed in a shell of CaCO ₃ (3). A multiphase particle is shown, consisting of a high contrast reactive phase and a low contrast SiO2 phase (4). The reactive part of the particle has a silica crust, and the core of the particle is partially enclosed in a shell of CaCO3.

In FIG. 11 is a back-scattered electron (BSE) image of a dense reacted cement paste. The image shows several examples of core-shell structures resulting from the reaction of multi-phase cement particles.

In FIG. 12 is a back-scattered electron (BSE) image of a dense reacted cement paste. The image shows a large multiphase particle with areas enriched in silicon dioxide, which indicates the existence of a reactive particle structure - a particle with voids.

Detailed description of the invention

The invention proposes new composite materials and binders characterized by unique microstructures, chemical compositions and adhesive strength, as well as methods for their preparation and use, for example, as various components of concrete in infrastructure, structures, road surfaces and landscape architecture. Composite materials and binders disclosed in the invention are prepared by carbonizing suitable calcium silicate materials (e.g., clinker and calcium silicate cement), which can be obtained from widely available inexpensive raw materials using processes suitable for use in large-scale industrial production. The process of the invention is highly adaptable to existing equipment and process conditions and can be

- 3 040455 is easy to use in industrial plants producing traditional Portland cement.

Composite materials can be produced with significantly lower energy consumption and CO2 emissions and can be used in a variety of concrete applications. The feedstock includes precursor materials such as calcium silicate particles (eg ground wollastonite) which form the binders. A liquid component is also used as the reaction medium, including liquid water and/or steam. Carbon dioxide (CO2) is consumed as a reactive compound in the carbonization process, resulting in the actual _CO2 sequestration. Various additives can be used to adjust the appearance and mechanical properties of the resulting composite material.

Binders and Composite Materials

In one aspect, the invention relates generally to a composite material obtained by carbonizing calcium silicate with CO2. The composite material includes a plurality of binder elements with one or more types of microstructures selected from: a binder element comprising a core of an unreacted carbonizable phase of calcium silicate, wholly or partially surrounded by a silica-enriched crust layer of varying thickness, which is wholly or partially enclosed in a shell of CaCO ₃ particles; a binder comprising a silica core resulting from the carbonization of a carbonizable calcium silicate phase, completely or partially surrounded by a silica-rich crust layer of varying thickness, which is completely or partially enclosed in a shell of CaCO ₃ particles; a binder comprising a silica core resulting from carbonization of a carbonizable calcium silicate phase, completely or partially enclosed in a shell of CaCO ₃ particles; a binder comprising a core of a non-carbonizable phase, fully or partially enclosed in a shell of CaCO3; a binding element comprising a multiphase core consisting of silicon dioxide formed as a result of carbonization of a calcium silicate phase with the ability to carbonize, and partially reacted calcium silicate, where the multiphase core is completely or partially surrounded by a silica-enriched crust layer of various thicknesses, which is completely or partially enclosed into a shell of CaCO ₃ particles; a binder comprising a multi-phase core consisting of a non-carbonizable phase and partially reacted calcium silicate, where the multi-phase core is completely or partially surrounded by a silica-enriched crust layer of various thicknesses, which is completely or partially enclosed in a shell of CaCO3 particles; a binding element comprising particles of partially reacted calcium silicate without a clearly defined core and a crust layer of silicon dioxide enclosed in a shell of CaCO3 particles; and a binding element, including porous particles without a clearly defined crust layer of silicon dioxide, enclosed in a shell of CaCO3 particles. Collectively, the plurality of bonding elements form a conjugated bonding matrix that provides bonding strength and fixation of the composite material.

In another aspect, the invention relates generally to a bonding matrix comprising a plurality of bonding elements. The binders are selected from a binder comprising a core of unreacted carbonizable calcium silicate phase, wholly or partially surrounded by a silica-enriched crust layer of varying thickness, wholly or partially enclosed in a shell of CaCO ₃ particles; a binder comprising a silica core resulting from the carbonization of a carbonizable calcium silicate phase, completely or partially surrounded by a silica-rich crust layer of varying thickness, which is completely or partially enclosed in a shell of CaCO3 particles; a binder comprising a silica core formed by carbonization of a carbonizable calcium silicate phase and wholly or partially enclosed in a shell of CaCO3 particles; a binder comprising a core of non-carbonizable phase, fully or partially enclosed in a shell of particles of CaCO ₃ ; a binding element comprising a multi-phase core consisting of silicon dioxide formed as a result of carbonization of a calcium silicate phase with the ability to carbonize, and partially reacted calcium silicate, where the multi-phase core is completely or partially surrounded by a silica-enriched crust layer of various thicknesses, which is completely or partially enclosed into a shell of CaCO ₃ particles; a binder comprising a multi-phase core consisting of a non-carbonizable phase and partially reacted calcium silicate, where the multi-phase core is completely or partially surrounded by a silica-enriched crust layer of various thicknesses, which is completely or partially enclosed in a shell of CaCO3 particles; a binding element comprising particles of partially reacted calcium silicate without a clearly defined core and a crust layer of silicon dioxide enclosed in a shell of CaCO3 particles; and a binding element comprising porous particles without a clearly defined crust layer of silicon dioxide, enclosed in a shell of particles of CaCO ₃ .

The silica-enriched cortical layer usually has varying thickness within the junction.

- 4 040455 biting element and from one connecting element to another connecting element, usually varying in the range from about 0.01 microns to about 50 microns. In particular preferred embodiments, the silica-rich crust layer has a thickness in the range of from about 1 µm to about 25 µm. As used herein, the term enriched in silica generally refers to a silica content that is significant relative to other material components, such as silica content greater than about 50% by volume. The remainder of the silica-enriched crust consists primarily of CaCO ₃ , eg 10% to about 50% CaCO ₃ by volume. The silica-rich crust layer may also include inert or unreacted particles, for example, from 10% to about 50% by volume of melilite. The silica-rich crust layer is typically characterized by a transition from being primarily silica to being primarily CaCO ₃ . Silica and CaCO ₃ may be present in the form of mixed or discrete regions.

As used herein, the term "carbonizable" refers to a material that can react with CO ₂ by undergoing a carbonization reaction under the conditions disclosed in the invention. A material is non-carbonizable if it does not react with CO ₂ as a result of the carbonization reaction occurring under the conditions disclosed in the invention. The terms reactive phase and carbonizable phase are used interchangeably to refer to a material phase that is carbonizable as defined in the invention. The terms inert phase and non-carbonizable phase are used interchangeably to refer to a material phase that is not carbonizable as defined in the invention. Examples of carbonizable phases or reactive phases include CS (wollastonite or pseudowollastonite, sometimes represented as CaSiO ₃ or CaO-SiO ₂ ), C ₃ S ₂ (rankinite, sometimes represented as Ca ₃ Si ₂ O7 or 3CaO-2SiO2), C ₂ S (belite, e-Ca ₂ SiO ₄ or larnite, Ca7Mg (SiO ₄ ) ₄ or bredigite, a-Ca ₂ SiO ₄ or y-Ca ₂ SiO ₄ , which are sometimes depicted as formulas Ca ₂ SiO ₄ or 2CaO-SiO ₂ ). Amorphous phases may also be carbonizable depending on their composition. Examples of non-carbonizable phases or inert phases include melilite ((Ca, Na, K) ₂ [(Mg, Fe ²⁺ , Fe ³⁺ , Al, Si) ₃ O7]) and crystalline silica (SiO ₂ ).

The silica-rich crust layer also has different silica contents from one binder to another binder, typically ranging from about 50% to about 90% by volume (eg, from about 60% to about 80%). In particular embodiments, the silica-enriched crust typically has a silica content ranging from 50% to about 90% by volume and a CaCO ₃ content ranging from about 10% to about 50% by volume. In particular embodiments, the silica-enriched crust has a silica content ranging from about 70% to about 90% by volume and a CaCO ₃ content ranging from about 10% to about 30% by volume. In specific embodiments, the silica-enriched crust has a silica content ranging from about 50% to about 70% by volume and a CaCO ₃ content ranging from about 30% to about 50% by volume.

The silica-enriched cortex may surround the nucleus with varying degrees of coverage anywhere from about 1% to about 99% (eg, from about 10% to about 90%). In particular embodiments, a silica-enriched cortex surrounds the core with a coverage rate of less than about 10%. In specific embodiments, a silica-enriched crust layer of various thicknesses surrounds the core with a coverage rate of greater than about 90%.

The plurality of binders may have any suitable average particle size and any suitable particle size distribution, depending on the desired properties and performance of the composite product. In specific embodiments, for example, the plurality of binders have an average particle size ranging from about 1 µm to about 100 µm (e.g., from about 1 µm to about 80 µm, from about 1 µm to about 60 µm, from about 1 µm to about 50 µm, from about 1 µm to about 40 µm, from about 1 µm to about 30 µm, from about 1 µm to about 20 µm, from about 1 µm to about 10 µm, from about 5 µm to about 90 µm, from about 5 µm to about 80 µm, about 5 µm to about 70 µm, about 5 µm to about 60 µm, about 5 µm to about 50 µm, about 5 µm to about 40 µm, about 10 µm to about 80 µm, approx. 10 µm to approx.

- 5 040455 positively 70 µm, from about 10 µm to about 60 µm, from about 10 µm to about 50 µm, from about 10 µm to about 40 µm, from about 10 µm to about 30 µm, from about 10 µm to about 20 µm).

Cement particles with specific microstructures may be more suitable for the formation of the bonding matrix disclosed in the invention. Generally, cement particles can be classified into two groups: single-phase particles and multi-phase particles.

Single-phase particles can exist in various forms, including: (i) reactive (having the ability to carbonize) wollastonite (CaSiO ₃ ), rankinite (Ca ₃ Si ₂ O ₇ ) and C ₂ S (Ca ₂ SiO ₄ ); (ii) partially reactive phases of various compositions; and (iii) inert (not carbonizable) phases such as melilite ((Ca, Na, K) ₂ [(Mg, Fe ²⁺ , Fe ³⁺ , Al, Si) ₃ O ₇ ]) and crystalline dioxide silicon (SiO2).

Multiphase particles can exist in various forms, including:

(i) a reactive reactive form, ie a combination of two or more reactive phases (eg CaSiO ₃ , Ca ₃ Si ₂ O ₇ , Ca ₂ SiO ₃ );

(ii) reactive - inert form, i.e. a combination of at least one reactive phase (eg CaSiO ₃ , Ca ₃ Si ₂ O ₇ , Ca ₂ SiO ₃ ) and at least one inert phase (eg (Ca, Na, K) ₂ [(Mg, Fe ²⁺ , Fe ³⁺ , Al, Si) ₃ O ₇ ], SiO ₂ );

(iii) inert - inert form, ie a combination of two or more inert phases (eg, (Ca, Na, K)2[(Mg, Fe ²⁺ , Fe ³⁺ , Al, SihOd, SiO2);

(iv) reactive - partially reactive form, ie a combination of at least one reactive phase (eg CaSiO3, Ca3Si2O7, Ca2SiO3) with a partially reactive amorphous phase;

(v) an inert - partially reactive form, i.e. a combination of at least one inert phase (eg (Ca, Na, K) ₂ [(Mg, Fe ²⁺ , Fe ³⁺ , Al, Si) ₃ O ₇ ], SiO ₂ ) with a partially reactive amorphous phase;

(vi) a reactive - slightly reactive - inert form, i.e. a combination of at least one reactive phase (eg CaSiO ₃ , Ca ₃ Si ₂ O ₇ , Ca ₂ SiO ₃ ) with at least one inert phase (eg (Ca , Na, K) ₂ [(Mg, Fe ²⁺ , Fe ³⁺ , Al, Si) ₃ O ₇ ], SiO ₂ ) and a partially reactive amorphous phase; and (vii) the shape of the void-containing particles, where a particle from one of the above categories does not have a maximum density and has internal or surface interconnected voids.

In FIG. 1(a)-1(f) are schematic representations of examples of connecting members according to exemplary embodiments of the present invention. In FIG. 1(a) shows a single-phase reactive particle (1) and various examples of binders that can be obtained from it. Image (5), for example, shows a microstructure in which the formation of a CaCO3 shell occurs only next to the silica crust formed as a result of the reaction of calcium silicate). In FIG. 1(b) shows a single-phase inert particle (1) and various examples of binders that can be obtained from it. In FIG. 1(c) shows a two-phase reactive particle (1) and various examples of binders that can be obtained from it. In FIG. 1(d) shows a two-phase inert particle (1) and various examples of binders that can be obtained from it. In FIG. 1(e) shows multi-phase reactive particles (1) (a), (1) (b), (1) (c) and so on, and various examples of binders that can be obtained from multi-phase reactive particles (2). In FIG. 1(f) shows a single-phase reactive particle with voids and examples of binders that can be obtained. It should be noted that these connecting elements are given as examples and are shown for the purpose of illustration and these images do not reflect the actual or relative shapes of the particles or their sizes.

The bonding element can be of any size and any regular or irregular, solid or hollow structure, which can be achieved, in any case, by the choice of raw materials and the technological process, taking into account the intended application. Examples of structures include cubes, cuboids, prisms, disks, pyramids, polyhedra or polyhedral particles, cylinders, balls, cones, rings, tubes, sickle particles, needles, fibers, filaments, flakes, spheres, almost spheroidal particles, granules, clusters, grains. , oblong-shaped particles, rods, flakes and so on.

In particular embodiments, the bonding element or bonding matrix may have one or more voids. Voids may be present in single-phase or multi-phase cores, or in bonding elements without well-defined cores. Voids may be present in reactive phases or in inert phases. Voids may be present in the resulting CaCO ₃ shell. Thus, voids may be present within the bonding element or located in the space between the bonding elements. Voids may be internal or surface, isolated or communicating voids.

Within the bonding matrix, the bonding elements can be positioned relative to each other.

- 6 040455 friend in any one of a variety of orientations. In FIG. 2(a)-2(f) is a schematic representation of an example of a bonding matrix that includes bonding elements in the form of fibers or plates in various orientations, diluted as much as possible by introducing the filler material shown in the space between the bonding elements. In FIG. 2(a), for example, shows a bonding matrix that includes bonding elements in the form of fibers arranged in a unidirectional (1-D) orientation (eg, located in the x-direction). In FIG. 2(b) shows a bonding matrix that includes flake-shaped bonding elements arranged in a bi-directional (2-D) orientation (eg, located in the x-axis and y-axis direction). In FIG. 2(c) depicts a bonding matrix that includes flake-shaped bonding elements arranged in a tri-directional (3-D) orientation (eg, located in the x, y, and z direction). In FIG. 2(d) shows a bonding matrix that includes platelet-shaped bonding elements arranged in a random orientation in which the bonding elements are not arranged in any particular direction. In FIG. 2(e) depicts a bonding matrix that includes a relatively high concentration of platelet-shaped binders that are arranged in a 3-D orientation. In FIG. 2(f) shows a binder matrix that includes a relatively low concentration of platelet-shaped binders that have a disordered orientation (percolation network structure). The composite material shown in Fig. 2(f) reaches the percolation threshold due to the fact that most of the connecting elements are in contact with each other, resulting in a continuous network of contacts from one end of the material to the other end of the material. The percolation threshold is the critical concentration above which the binder elements begin to exhibit the ability to form bonds over long distances or in an ordered orientation, such as in FIG. 2(e), or in disordered orientation, such as in FIG. 2(f), connecting elements. Examples of bonding types can be found, for example, in Newnham, et al., Connectivity and piezoelectric-pyroelectric composites, Mat. Res. Bull. Vol. 13, pp. 525-536, 1978.

The binder matrix may also include a plurality of coarse or fine aggregate particles, which may be any suitable material having any suitable particle size and any suitable particle size distribution. In particular preferred embodiments, for example, the aggregate particles are made from a material with a high content of calcium carbonate, such as limestone (eg, lime powder). In some materials, the aggregate particles are made from one or more SiO ₂ or silicate based materials such as quartz, mica, granite, and feldspar (eg, ground quartz, ground mica, ground granite, ground feldspar).

In specific embodiments, the aggregate particles may include natural, synthetic, and reclaimed materials such as glass, recycled glass, coal slag, fly ash, high calcium carbonate material, and high magnesium carbonate material.

In particular embodiments, the plurality of aggregate particles have an average particle size in the range of about 5 µm to about 7 mm (e.g., about 5 µm to about 5 mm, about 5 µm to about 4 mm, about 5 µm to about 3 mm , from about 5 µm to about 2 mm, from about 5 µm to about 1 mm, from about 5 µm to about 500 µm, from about 5 µm to about 300 µm, from about 20 µm to about 5 mm, from about 20 µm up to about 4 mm, from about 20 µm to about 3 mm, from about 20 µm to about 2 mm, from about 20 µm to about 1 mm, from about 20 µm to about 500 µm, from about 20 µm to about 300 µm, about 100 µm to about 5 mm, about 100 µm to about 4 mm, about 100 µm to about 3 mm, from about 100 µm to about 2 mm, from about 100 µm to about 1 mm).

The weight ratio of binders to aggregate particles can be any ratio depending on the intended use of the composite material product. For example, the weight ratio of binders to aggregate particles may be in the range of about (50-99): about (1-50), for example, about (60-99): about (1-40), about (80-99): approximately (1-20), approximately (90-99): approximately (1-10), approximately (50-90): approximately (10-50), approximately (50-70): approximately (30-50). In specific embodiments, depending on the application, the weight ratio of binders to aggregate particles may be in the range of about (10-50): about (50-90), for example, about (30-50): about (50-70 ), approximately (40-50): approximately (50-60).

Depending on the materials and conditions used to form the composite, one or more types of binders may be preferred over other types of binders in the binder matrix of the composite. For example, techno

- 7 040455 The logical process for the production of clinker or cement and the raw materials used in it make it possible to obtain clinker or cement microstructures that affect carbonization and the resulting composite material. In addition, the grinding of clinker can also affect the particle size and particle size distribution and the overall microscopic morphology of the cement, which can in turn affect the microstructures of the binders within the composite material after carbonization.

An additional factor that influences the formation of a binder matrix is the characteristic of the reactivity of the cement subjected to carbonization. For example, a cement may have a total particle surface area of at least 10% covered by a carbonizable phase. In specific embodiments, the implementation of the cement may be characterized by a total surface area of the particles, at least 20% of which is covered with the ability to carbonize the phase. In specific embodiments, the implementation of the cement may be characterized by a total surface area of the particles, at least 30% of which is covered with the ability to carbonize the phase. In specific embodiments, the implementation of the cement may be characterized by a total surface area of the particles, at least 40% of which is covered with the ability to carbonize the phase. In specific embodiments, the implementation of the cement may be characterized by a total surface area of the particles, at least 50% of which is covered with the ability to carbonize the phase. In specific embodiments, the implementation of the cement may be characterized by a total surface area of the particles, at least 60% of which is covered with the ability to carbonize the phase. In specific embodiments, the implementation of the cement may be characterized by a total surface area of the particles, at least 70% of which is covered with the ability to carbonize the phase. In particular embodiments, for example, the cement may have a total particle surface area of at least 80% covered by the carbonizable phase. In specific embodiments, the implementation of the cement may be characterized by a total surface area of the particles, at least 90% of which is covered with the ability to carbonize the phase. In specific embodiments, the implementation of the cement may be characterized by a total surface area of the particles, at least 95% of which is covered with the ability to carbonize the phase. In specific embodiments, the implementation of the powder material is characterized by a total surface area of the particles, which is almost completely covered with the ability to carbonize the phase.

As used herein, the term calcium silicate or calcium silicate composition generally refers to natural minerals or synthetic materials that are composed of one or more calcium silicate phase groups comprising CS (wollastonite or pseudowollastonite, which is sometimes represented by the formulas CaSiO ₃ or CaO-SiO ₂ ), C ₃ S ₂ (rankinite, which is sometimes represented by the formulas Ca ₃ Si ₂ O ₇ or 3CaO-2SiO2), C ₂ S (belite, e-Ca ₂ SiO ₄ or larnite, Ca ₇ Mg (SiO ₄ ) ₄ or bredigite, a -Ca ₂ SiO ₄ or y-Ca ₂ SiO ₄ , which is sometimes represented by the formulas Ca ₂ SiO ₄ or 2CaO-SiO 2 ), an amorphous phase based on calcium silicate, each of these materials may include one or more other metal ions and oxides (eg oxides of aluminum, magnesium, iron or manganese) or mixtures thereof, or may include an amount of magnesium silicate in natural or synthetic form(s) ranging from trace amounts (1%) to about 50% or more by weight.

Regulation of the carbonization process and the curing process

This invention further provides methods for making novel composite materials that cure predominantly by reaction with CO2. In addition to CO2, another reagent used in the process is water. In preferred embodiments of the invention, CO ₂ is used as a reacting compound, which results in CO ₂ sequestration and the formation of binders in the resulting composite materials. Carbonization, for example, can be carried out using CO ₂ and water in controlled hydrothermal liquid phase sintering (HLPS) to achieve an adhesive strength that allows the various components of the composite material to be held together. A discussion of the various parameters for implementing the HLPS method can be found in US Patent No. 8114367, US Pub. No. US 2009/0143211 (Appl. Serial No. 12/271566), US Pub. No. US 2011/0104469 (Appl. Serial No. 12/984299), US Pub. No. 2009/0142578 (Appl. Serial No. 12/271513), US Pub. No. 2013/0122267 (Appl. Serial No. 13/411218), US Pub. No. 2012/0312194 (Appl. Serial No. 13/491098), WO 2009/102360 (PCT/US2008/083606), WO 2011/053598 (PCT/US2010/054146), WO 2011/090967 (PCT/US2011/021623), US Provisional Patent Application No. 61/708423 filed October 1, 2012 and US Patent Application Nos. 14/045,758, 14/045519, 14/045766, 14045540, all filed October 3, 2013, US Patent Application Nos. 14/207413, 14/207421, filed March 12, 2014, US Patent Application Nos. 14/207920, 14/209238, filed March 13, 2014, US Patent Application No. 14/295601, 14/295402, filed June 4, 2014, the contents of each of these documents are hereby incorporated by reference in all respects.

It is assumed that the following reactions occur during the carbonization of calcium silicate.

- 8 040455

CaSiO ₃ (t) + CO ₂ (g) CaCO ₃ (t) + S1O ₂ (t) (1)

Ca ₃ Si ₂ O ₇ (t) + 3CO ₂ (g) 3CaCO ₃ (t) + 2S1O ₂ (t) (2)

Ca ₂ SiO ₄ (t) + 2CO ₂ (g) 2CaCO ₃ (t) + S1O ₂ (t) (3)

Typically, CO2 is introduced in the form of a gas that is dissolved in the infiltration fluid such as water. The dissolution of CO2 leads to the formation of acidic carbon compounds (such as carbonic acid, H2CO3), which lowers the pH of the solution. The slightly acidic solution incongruently dissolves the calcium compounds in the calcium silicate phases. Calcium can be leached from calcium-containing amorphous phases by a similar mechanism. The released calcium cations and dissociated carbonate compounds cause precipitation of insoluble carbonates. It is assumed that the silica-rich layers remain on the mineral particles in the form of calcium-depleted layers.

The CaCO3 produced by these or any other carbonization reactions involving CO ₂ described herein may exist in the form of one or more of the various CaCO ₃ polymorphs (eg, calcite, aragonite, and vaterite). The CaCO ₃ particles are primarily in the form of calcite, but they may also be present in the form of aragonite or vaterite or as a combination of two or three polymorphs (e.g. calcite/aragonite, calcite/vaterite, aragonite/vaterite or calcite/aragonite/vaterite ).

CO2 can be used in any suitable purity, depending on the desired carbonization result. For example, technical grade CO2 with a purity of about 99%, which is produced by many industrial gas companies such as Praxair, Inc., Linde AG, Air Liquide and others, can be used. The CO2 production can be stored in large pressurized storage tanks in the form of liquid carbon dioxide, temperature controlled to maintain the desired vapor pressure of CO ₂ , for example, at about 2.07 MPa. This gas is then fed through a gas pipeline into a closed space or curing chamber with CO ₂ (for carbonization). In the simplest system, CO ₂ is passed through the enclosed space at a controlled rate sufficient to displace the air in the enclosed space. Typically, the purge time may depend on the size of the enclosed space and the rate at which CO ₂ is supplied. In many systems, this process of purging an enclosed space to expel air can be carried out for a time measured in minutes, bringing the CO ₂ concentration to an acceptable level, after which curing can be carried out. In simple systems, gaseous CO ₂ is then introduced into the system at a predetermined rate that maintains the CO 2 concentration at a level sufficient to carry out the curing reaction.

Carbon dioxide concentrations can be continuously monitored and systematically maintained. The CO ₂ concentration may be measured or continuously monitored directly in the system, for example by non-dispersive infrared spectroscopy (NDIR), and a controller such as a programmable logic controller (PLC) may be used to control the CO ₂ concentration to a set point, for example by means of an electronic /automatic control valve. In NDIR measurements, a sample of the gas stream is taken from the system using a low flow pump. Prior to sampling for NDIR analysis, a condenser is used to remove moisture from the gas stream. Measurement of the moisture content of the gas flow in the system can be carried out by dry-bulb-wet-bulb psychrometric analysis, using a device with dry and wet bulbs, or using another type of humidity sensor. The true CO ₂ concentration can be calculated using a computer control system or PLC. Once the true CO ₂ concentration is determined, in the event that carbon dioxide has been consumed and its concentration at that point in time has fallen below the set value, an actuated dosing control valve can add a certain amount of dried CO ₂ to the system. In various embodiments, if necessary, the set point can be changed depending on the point in time, based on the experience of curing specific compositions, the shape and size of samples of composite materials.

In FIG. 3 is an example of a schematic diagram of a curing chamber in which humidification is provided. As shown in FIG. 3, water is supplied and water vapor is added to the gaseous medium that circulates inside the curing chamber. The water may be any suitable source of drinking water. In some embodiments, ordinary tap water is used. In some embodiments, water may be converted to steam by passing it through an aerosol or mist spray nozzle, an electric steam generator, a gas-fired steam generator, or by heating the water to a temperature above the temperature of the gas in the chamber to cause the liquid water supply to evaporate, for example which is a drum reactor with a submersible type heater. In yet another embodiment, CO ₂ may be introduced into the system after it has been bubbled through the heated water feed to increase the relative humidity of the feed gas stream, an example of which is a drum reactor configured for flow through or open loop operation.

- 9 040455

Relative humidity is another important parameter for both conventional concrete curing and composite curing with CO2. In a traditional curing chamber, there is a humid air environment that is mainly composed of nitrogen, oxygen, and water vapor. In these systems, relative humidity is most often measured using a standard capacitive sensor. However, CO ₂ curing chambers have an atmosphere composed primarily of carbon dioxide, which is not compatible with some types of these sensors. The CO2 composite curing systems described herein may employ sensory methods such as dry and wet bulb methods that use psychrometric ratios for carbon dioxide and water vapor, or instruments for measuring the dipole polarization of water vapor, or hygrometers with refrigerated mirror, or capacitive humidity sensors.

Depending on the type and geometry of the product to be cured, the design of the chamber, and the effectiveness of the packaging of the product in the chamber, it may be necessary to either reduce or increase the humidity and adjust it to the specified set point. The setpoints can be any value between 1 and 99% RH. Three different methods of moisture control can be used in the CO2 curing process of the composite material, which can be combined into one single system. One method of wetting, in one embodiment of a CO2 curing system, is shown in FIG. 3. Another method is to remove moisture from the composite curing system with CO2. A simple method for reducing relative humidity is to displace the wet gas in the system with a dry gas such as carbon dioxide. In yet another embodiment, it is possible to reduce the relative humidity and thus remove water vapor from the gas in a no-purge method, which in one preferred embodiment is a cooled heat exchanger in which water is extracted.

In FIG. 4 is an example of a block diagram of a curing chamber that uses a variety of humidity control methods as well as the ability to both control and replenish CO2 using constant flow mode or pressure control, and that has the ability to control temperature in accordance with the principles of the invention. . This system is an example of a system that can provide closed-loop or closed-loop control that provides setpoints for operating parameters such as CO ₂ concentration, humidity, and temperature that are desired at specified times in the process cycle, and in which measurements are made to provide information on whether the actual value of the controlled parameter matches the required value. If a deviation from the required value is detected, a corrective action is taken to bring the parameter value in line with the required value. Such control systems can be expensive and complex, and they can be applied to high value products or products that require very precise process control.

Another control parameter is the gas velocity and the supply control of the material that is cured with CO2 in the system. The gas velocity may depend on process equipment variables including, but not limited to, chamber design, baffle design, fan size, fan speed/power, number of fans, temperature gradient within the system, shelf design within the system, and sample dimensions within the system. The simplest method of adjusting the speed of the gas inside the chamber is to adjust the rotation speed of the blower (RPM), usually by using a variable frequency drive to control the speed of the blower motor. A blower can be used to circulate the gas at the required rate in the curing chamber. The velocity of the gas in the system is measured by a variety of methods including, but not limited to, measurements with Pitot tubes and laser Doppler systems. The gas velocity measurement signal can be sent back to the computer system or PLC and used as a curing process control parameter.

Temperature control is another important parameter of the calcium silicate carbonization process, which results in the formation of the desired binders and composite material according to the invention. The temperature can be measured by a sensor such as a thermocouple or resistance temperature detector (RTD). The measurement signal can be sent back to the controller or computer, which can regulate the energy in the heat exchanger and thereby correct the temperature of the whole system over time. The blower is an important component of the heating system, as it facilitates the transfer of thermal energy to the gas, which transfers this thermal energy to the products in the chamber itself, which plays an important role in controlling the moisture content of the samples. Heating can be carried out electrically or by burning gas. Jacketed heaters may be used to control the temperature of the CO ₂ that is passed through the chamber in contact with the jacketed heater, in which case any suitable

- 10 040455 general heat source. Outdoor heating methods may include, but are not limited to, electrical heating, water heating, or hot oil heating. At present, systems with indirect gas heating are used for CO2 curing chambers, and direct heating with gas burners is not used, as this leads to air and combustion products entering the system, which dilutes the CO2 and makes it difficult to control the CO2 concentration. Some lower capacity systems, such as drum reactors, use electrically heated jacketed heaters to heat the entire surface of the chamber rather than a heating element inside the chamber.

The method of obtaining a composite material and binders according to the invention can be configured so that it allows you to achieve specific performance characteristics of carbonized products. Typically, such a method includes: mixing a powdered composition (cement) and a liquid composition to form a slurry mixture; molding the slurry mixture into the desired shape, either by pouring the slurry into a mould, pressing the slurry into a mold, pressing the slurry into a vibroform, extruding the slurry, molding the slurry in a slipform, or by using any other molding method commonly used in the manufacture of concrete products, and curing shaped slurry mixture at a temperature in the range from about 20°C to about 150°C for from about 1 hour to about 80 hours in a steam atmosphere comprising water and CO ₂ and having a pressure in the range from about ambient atmospheric pressure to about pressure 0.34 MPa above ambient atmospheric pressure and having a CO2 concentration of from about 10% to about 90% to form a composite material. Thus, the curing of the shaped slurry mixture can be successfully carried out at a temperature in the range from about 20°C to about 150°C. Curing can be carried out for from about 1 hour to about 80 hours. The pressure at which curing occurs can be from about ambient atmospheric pressure to about 0.34 MPa ambient atmospheric pressure. The CO2 concentration may range from about 10% to about 90%.

The time required to cure a composite material is determined by the ability of water vapor and CO2 gas to diffuse through the object. Generally, thicker objects take longer to cure than thinner objects. Likewise, high density objects (and smaller open pore spaces) take longer to cure than low density objects (and large open pore spaces). The following table provides examples of how cure times may vary depending on the thinnest thickness (or wall thickness or section thickness) in three dimensions and the bulk density of the resulting object.

Excellent product properties and performance for special applications can be obtained. In particular embodiments, the composite material has a compressive strength of from about 20 MPa to about 175 MPa (e.g., from about 20 MPa to about 150 MPa, from about 20 MPa to about 120 MPa, from about 20 MPa to about 100 MPa, from about 20 MPa to approximately 80 MPa, approximately 20 MPa to approximately 65 MPa, approximately 30 MPa to approximately 120 MPa, approximately 30 MPa to approximately 100 MPa, approximately 30 MPa to approximately 65 MPa, approximately 60 MPa to approximately 120 MPa, from about 90 MPa to about 130 MPa, from about 100 MPa to about 175 MPa, from about 120 MPa to about 175 MPa, from about 140 MPa to about 175 MPa, from about 150 MPa to about 175 MPa).

In particular embodiments, the composite material has a flexural strength of from about 3 MPa to about 30 MPa (e.g., from about 3 MPa to about 25 MPa, from about 3 MPa to about 20 MPa, from about 3 MPa to about 15 MPa, from about 3 MPa to about 10 MPa, from about 10 MPa to about 30 MPa, from about 20 MPa to about 30 MPa, from about 5 MPa to about 20 MPa).

In particular embodiments, the composite material has a water uptake of less than about 10%. In still other embodiment materials, the composite material has a water uptake of less than about 8%. In still other embodiment materials, the composite material has a water absorption of less than about 5%. In still other embodiment materials, the composite material has a water uptake of less than about 4%. In still other embodiment materials, the composite material has a water uptake of less than about 3%. In still other embodiment materials, the composite material has a water uptake of less than about 2%. In still other embodiment materials, the composite material has a water uptake of less than about 1%.

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The composite material may have one or more of the desired textures, patterns, and physical properties, in particular those found in natural stone. In specific preferred embodiments, the implementation of the composite material has a visual structure similar to natural stone. Other characteristics include colors (for example, black, white, cyan, pink, gray (pale gray to dark grey), green, red, yellow, brown, teal (bluish green), or magenta) and textures.

Composite Material Products and Applications

The composite material and binders described in the invention, due to their excellent properties, which can be adjusted if necessary, as described in the invention, can have a variety of applications, for example, in infrastructure facilities, structures, road surfaces, landscape architecture, energy accumulation and storage systems , in power generation, in agriculture, in the automotive industry, in the production of abrasives and cutting tools, and so on.

The composite material and binders described in the invention can be used in many applications where Portland cement, lime cement or related mineral binders are used. The composite material of the invention can be used in any application that uses traditional structural or quality concrete, such as dams, bridges, swimming pools, houses, streets, terraces, foundations, balustrades, pure clinker cement tiles, mosaic tiles, paving stones streets, lampposts, manholes, or combinations thereof.

Various additives can be used to modify and adjust the appearance and/or mechanical properties of the resulting composite material, such as additives selected from one or more of pigments, colored glass and/or colored quartz. Additives can also be used to reduce water consumption and change rheology.

In specific embodiments, the implementation of the composite further includes a pigment. The pigment may be uniformly dispersed or substantially non-uniformly dispersed in the bonding matrices, depending on the desired composite material. The pigment may be any suitable pigment including, for example, oxides of various metals (eg, iron oxide, cobalt oxide, chromium oxide). The pigment may be any color or any colors, for example, selected from black, white, blue, grey, pink, green, red, yellow or brown. The pigment may be present in any suitable amount depending on the desired composite material, for example, in an amount in the range from about 0.0% to about 10% by weight (for example, from about 0.0% to about 8%, about 0.0% to about 6%, about 0.0% to about 5%, about 0.0% to about 4%, about 0.0% to about 3%, about 0.0% to about 2%, from about 0.0% to about 1%, from about 0.0% to about 0.5%, from about 0.0% to about 0.3%, from about 0.0% to about 0.2%, from about 0.0% to about 0.1%).

In specific embodiments, the binder/matrix is mixed with fibres, sand, aggregates and/or other additives such as defoamers and/or ultrafine particles such as fumed silica and CaCO ₃ to form glass fiber reinforced concrete (FRC), which has performance characteristics similar to fiber reinforced composites and/or ultra high strength fiber concrete (UHPC). These solids can be used in the same applications that they are used in conventional glass fiber reinforced concrete (FRC) and/or ultra high strength fiber reinforced concrete (UHPC). In an alternative embodiment, by controlling fluidity (eg, by optimizing the water content of the manufacturing process), other types of concrete products can be obtained. Products include shotcrete, self-compacting concrete, roller compacted concrete, or combinations thereof.

In another embodiment, the binder/matrix is mixed with a metal such as aluminum and Ca(OH) ₂ and autoclaved, or by controlling the porosity using various assistive technologies such as vacuum or air entrainment, a material is obtained that mimics / resembles autoclaved aerated concrete (AAC). This material can be used for the same purposes as traditional AAC autoclaved aerated concrete.

In specific embodiments, the binder/matrix is mixed with sand and/or low density aggregates (e.g. <2.0 g/cm ³ density, e.g., expanded vermiculite or perlite, pumice, expanded slag, expanded shale, or their combinations), and when controlling porosity, these composites can be used as lightweight concrete or cellular concrete, aerated lightweight concrete, variable density concrete, foamed concrete or ultralight concrete, or any other material related to these types of concrete. In another embodiment, the binder/matrix is mixed with high density aggregates.

- 12 040455 density (for example, with a density of >3.2 g/cm ³ ), and the resulting product may be a heavy concrete.

The tie/matrix described herein can be used in combination with (and thus reinforced with) steel or other metallic reinforcing materials to produce reinforced concrete products that can be used for the same purposes as traditional concrete structures. The material may be prestressed to produce a material that mimics/resembles prestressed concrete. In particular embodiments, the binder/matrix can be cast into huge molds to produce a material that mimics/resembles cast-in-situ concrete. These types of in-situ concrete can be used in the construction of a gravity dam, large containment structures, or both. The concrete obtained from the bonding element and bonding matrix described in the invention can also be made with different textures for decorative or functional purposes.

In some embodiments, the composite material of the invention can be made to have excellent corrosion resistance to protect steel reinforcement in high chloride environments and to provide long service life in harsh sulfate environments. The composite material can be used in highly specialized applications such as sound shielding and/or radiation shielding. In one embodiment, the material may have the required fire resistance and may be used to make refractory products. The material may also withstand extreme weather conditions such as, for example, freezing conditions, high temperatures in deserts, or extreme weather fluctuations, and/or be resistant to sudden changes in temperature. The material may also be suitable for special use in sea water, low temperature environments and/or blast resistant structures. In some embodiments, the implementation of the material can be used in earthquake-resistant structures and/or geosynthetic type structures.

The binders of the invention can be mixed with additives including CaCO ₃ or gypsum and sand to form monolithic solids. The binders of the invention may also be mixed with sand or other minerals to form mortar or cement paste, and the resulting material may be used for the same purposes as traditional mortar and cement paste. The binders of the invention may be mixed with metallic or organic or ceramic fibers to form a fiber-reinforced cement. The resulting material can be used for the same purposes as conventional fibre-reinforced cements.

Any suitable aggregates may be used to form composite materials from the carbonizable composition of the invention, for example materials containing calcium oxide or silica. Examples of aggregates include inert materials such as dark diabase, building sand, fine gravel. In particular preferred embodiments, lightweight aggregates such as perlite or vermiculite can also be used as aggregates. Materials such as industrial solid waste (eg fly ash, slag, fine silica dust) can also be used as fine aggregates.

The plurality of aggregates may have any suitable average particle size and any suitable particle size distribution. In particular embodiments, the plurality of aggregates have an average particle size in the range of from about 0.25 mm to about 25 mm (e.g., from about 5 mm to about 20 mm, from about 5 mm to about 18 mm, from about 5 mm to about 15 mm). mm, approximately 5 mm to approximately 12 mm, approximately 7 mm to approximately 20 mm, approximately 10 mm to approximately 20 mm, approximately 3.18 mm, approximately 6.35 mm, approximately 9.52 mm, approximately 12, 70 mm, approximately 19.05 mm).

Chemical additives, such as plasticizers, superplasticizers, set retarders, set accelerators, dispersants, and other rheology modifying agents, may also be incorporated into the composite material. Some commercial chemical additives may also be included, such as Glenium™ 7500 from BASF Chemicals and Acumer™ from Dow Chemical Company. In specific embodiments, one or more pigments may be uniformly dispersed or substantially non-uniformly dispersed in the binder matrices, depending on which composite material is desired. The pigment may be any suitable pigment including, for example, oxides of various metals (eg black iron oxide, cobalt oxide and chromium oxide). The pigment may be any color or any colors, for example, selected from black, white, blue, grey, pink, green, red, yellow and brown. The pigment may be present in any suitable amount, depending on which composite material is desired, for example, in an amount in the dia.

- 13 040455 range from about 0.0% to about 10% by weight.

It should be appreciated that the calcium silicate compositions, phases and methods disclosed herein can be adapted to use magnesium silicate phases instead of or in addition to calcium silicate phases. As used herein, the term magnesium silicate refers to natural minerals or synthetic materials that are composed of one or more groups of compounds containing magnesium and silicon, including, for example, Mg ₂ SiO ₄ (also known as forsterite) and Mg ₃ Si ₄ O ₁₀ ( OH) ₂ (also known as talc), wherein the material may include one or more other metal ions or oxides (for example, oxides of calcium, aluminium, iron or manganese) or mixtures thereof, or may include an amount of calcium silicate in natural or synthetic form(s). ) ranging from trace amounts (1%) to about 50% or more by weight.

Examples

Samples of carbonizable calcium silicate cements were embedded in epoxy resin, polished and coated with a layer of graphite to obtain information on the distribution of phases within individual particles. The samples were analyzed by scanning electron microscopy (SEM) in the back-scattered electron (BSE) spectrum imaging mode. The contrast of each phase depends on its stoichiometry, with denser phases containing elements with higher mean atomic number appearing more clearly in the image than less dense phases with lower mean atomic number. The contrast of different phases can be correlated by comparing the contrast ratio η of a back-scattered electron (BSE) image calculated using the average atomic number Ζ of each phase.

InZ 1 _ n \u003d -g -\u003e 10) ° (Equation 1)

The average atomic number Z of each phase is the sum of the atomic masses of each atom present in the phase divided by the total number of atoms, where N is the number of each element with atomic number A and atomic mass Z (ZNA is molecular weight).

(Equation 2)

The values of η for the phases present in the cement particles are given in Table. 1. Amorphous phases have a variable chemical composition that cannot be determined by diffraction methods. For most cements, the amorphous phase will have a composition similar to that of the melilite phase. In cements with lower Al ₂ O ₃ and MgO content, the amorphous phase will have a higher mean atomic number and therefore will be more luminous in back-scattered electron (BSE) images. The identity of the phases is confirmed by measuring the individual phases with an X-ray microprobe.

Table 1. Calculated BSE contrast ratio values for phases present in carbonizable calcium silicate cement particles.

Phase η _SiO2 0.127 CaCO ₃ 0.148 A1 - Melilite (Ca ₂ Al ₂ SiO ₇ ) 0.154 Md - Melilite (Ca ₂ MgSi ₂ O ₇ ) 0.154 Wollastonite (CaSiO ₃ ) 0.160 Rankinite (Ca ₃ Si ₂ O ₇ ) 0.166 Belite (Ca ₂ SiO ₄ ) 0.171

^a) The highest value will correspond to the phase with the highest brightness. The calcium silicate phases have the highest contrast in back-scattered electron (BSE) images and will be the phases with the highest brightness in back-scattered electron (BSE) images. The darkest areas in the image correspond to pores or voids filled with carbon-based installation resin.

Experimental cements were prepared by three different methods with different final chemical compositions. Experimental cement 1 was prepared from limestone and sand ground to a fineness of 85%, passing through a 200 mesh sieve. Limestone and sand were mixed to obtain a total atomic ratio of calcium to silicon of approximately 1. The crushed and mixed raw materials were processed in a rotary kiln at max.

- 14 040455 a low temperature of approximately 1200°C and a residence time of 30 to 60 minutes in order to react the powder and obtain grains of cement clinker from sintered carbonizable calcium silicate, mainly consisting of carbonizable calcium silicates, melilites, amorphous phase with a composition similar to melilite and unreacted silica. The content of oxides in this cement, determined by X-ray fluorescence (XRF), is given in table. 2. The phase composition of this cement, determined by X-ray diffraction analysis (XRD), is given in Table. 3. Then, the cement clinker was ground using a double-chamber closed-loop ball mill. To obtain crushed cement with an average particle diameter of 12 μm, the feed rate of the material, the speed of rotation of the ball mill, and the air flow in the pneumatic separator were controlled. In FIG. 5 shows a compacted material of reacted particles obtained using this cement and exposed to an atmosphere containing >95% CO2 at 60°C for 18 hours.

Experimental cement 1 was examined in detail by back-scattered electron (BSE) scanning electron microscopy (SEM) combined with X-ray microprobe analysis. The elemental composition determined using an X-ray microprobe was compared with the phases identified by X-ray diffraction analysis (XRD). The atomic composition of the phases, determined using an X-ray microprobe, is given in Table. 4. This analysis identified an additional phase, brownmillerite or Ca ₂ (Al, Fe) ₂ O ₅ , as well as two distinct partially reactive amorphous phases: a low Al amorphous phase, phase 1, and an amorphous AL high phase, phase 2. FIG. 6, 7, and 8, the compositional analysis data collected in combination with the phase contrast observed in the back-scattered electron (BSE) images was used to create false color maps of unreacted particles. Many examples of multiphase particles of various classifications are found.

Table 2. The content of oxides in the experimental cement 1, determined by X-ray fluorescence (XRF).

_SiO2 CaO A1 ₂ O _{3 Fe2O3 _} MgO so ₃ K ₂ O Ν3-2θ _TiO2 p ₂ o _{5 Mn2O3 _} 44.9% 43.8% 5.3% 18% 1.2% 0.3% 2.0% 0.4% 0.2% 0.1% 0.0%

Table 3. Phase composition of experimental cement 1 determined by X-ray diffraction analysis (XRD).

Wollastonite CasiO ₃ Rankinite Ca3Si ₂ O7 Belite Ca ₂ SiO ₄ Amorphous phase of variable composition Silicon dioxide SiO ₂ Lime CaO Melilites composition variable 15% 19% 14% thirty% 5% 1% 16%

- 15 040455

Table 4. Atomic composition of phases in experimental cement 1, determined using an X-ray microprobe (expressed in atomic %).

Phase ABOUT Na mg Al Si s To Ca Ti Mn Fe wollastonite/pseudowollastonite 59.5 0, 0 0.0 0.6 1θ, 7 0.0 0.3 20, 8 0.1 oh, 0 oh, 1 Rankinitis 58.0 0, 0 0.2 0.4 15, 8 0.0 0.1 25.5 0.0 oh, 0 oh, 0 Belit 56, 8 0, 0 ο,ι 0.6 13, 3 0.0 0.2 28, 8 0.0 0, 0 0, 1 Amorphous (1) 62.2 0.7 0.8 0.7 36, 1 0.0 4.2 4.7 0.1 oh, 0 oh, 4 Amorphous (2) 60.0 0.8 0.4 9.3 18, 8 0.0 6.3 4.1 0.0 oh, 0 oh, 1 brownmillerite 55, 9 0, 0 0.7 7.0 3.3 0.4 0.3 23, 9 0.4 oh, 1 8, 0 melilite 58, 3 0.4 2.1 8.8 12.1 0.0 0.3 17, 2 0.0 oh, 0 oh, 8 Silica 66.6 0, 0 0.0 0.3 33.0 0.0 0.0 0, 0 0.0 oh, 0 oh, 0 Lime 50.0 0, 0 0.0 0, 0 0, 0 0.0 0.0 50.0 0.0 oh, 0 oh, 0

In the case of Experimental Cement 2, high purity limestone and sand were crushed and mixed to give a total calcium to silicon atomic ratio of approximately 1. The crushed and mixed raw materials were granulated by mixing with water and loaded into refractory containers. The containers and granular raw materials were fired at 1500° C. in an electric furnace to produce cement clinker from sintered carbonizable calcium silicate, mainly composed of reactive calcium silicates, an amorphous phase with a composition similar to wollastonite, and unreacted silica. The content of oxides in this cement, determined by X-ray fluorescence (XRF), is given in table. 5. The phase composition of this cement is given in Table. 6. The resulting raw material was crushed using a jet mill. To obtain particles with an average size of 12 μm, the material feed rate, the geometric dimensions of the mill, and the air pressure were controlled. The compacted ground cement material was exposed to an atmosphere containing >95% CO2 at 60° C. for 18 hours. FIG. 9 and FIG. 10 shows reacted single-phase and multi-phase particles.

Table 5. The content of oxides in experimental cement 2, determined by X-ray fluorescence (XRF).

Sio ₂ CaO A1 ₂ O ₃ Fe ₂ o ₃ MgO SO _{3 K2O Na2O TiO2} p ₂ 0 ₅ Mp ₂ 0z 45.8% 51.1% 1.8% 0.4% 0.6% 0.3% 0.3% 0.0% 0.0% 0.0% 0.0%

Table 6. Phase composition of experimental cement 2 determined by X-ray diffraction analysis (XRD).

Wollastonite CaSiO ₃ Rankinite Ca ₃ Si ₂ O ₇ Belite Ca ₂ SiO ₄ Amorphous phase of variable composition Silicon dioxide SiO ₂ Lime CaO Melilites of variable composition 20% 0% eleven% 68% 1% 0% 0%

Received having the ability to carbonize calcium silicate (experimental cement 3). To obtain cement, limestone and sand were ground to a fineness of 85%, passing through a 200 mesh sieve. Limestone and sand were mixed to obtain a total atomic ratio of calcium to silicon of approximately 1. The crushed and mixed raw materials were subjected to processing in a rotary kiln at a maximum temperature of approximately 1260°C and a residence time of 30 to 60 minutes in order to react the powder and obtain grains of cement clinker from sintered carbonizable calcium silicate, essentially consisting of carbonizable calcium silicates, melilite, an amorphous phase with a composition similar to melilite, and unreacted silica. The content of oxides in this cement, determined by X-ray fluorescence (XRF), is given in table. 7. The phase composition of this cement, determined by X-ray diffraction analysis (XRD), is given in table. 8. Then, the cement clinker was ground using a double-chamber closed-loop ball mill. To obtain crushed cement with an average particle diameter of 12 μm, the feed rate of the material, the speed of rotation of the ball mill and the air flow in the pneumatic separator were controlled. In FIG. 11 and FIG. 12 shows compressed materials from reacted particles obtained using this cement and exposed to an atmosphere containing >95% CO ₂ at 60°C for 18 hours.

Table 7. The content of oxides in the experimental cement 3, determined by X-ray fluorescence (XRF).

_SiO2 CaO A1 ₂ 0z _{Fe2O3 _} MDO so ₃ K ₂ O _Na2O Т1О ₂ p ₂ o ₅ MP ₂ O ₃ 43, 8 42.9% 6.0% 2.5% 2.0% 10% 1.1% 0.1% 0.3% 0.2% 0.1%

Table 8. Phase composition of experimental cement 3 determined by X-ray diffraction analysis (XRD).

Wollastonite CasiO ₃ Rankinite Ca ₃ Si ₂ O ₇ Belite Ca ₂ SiO ₄ Amorphous phase of variable composition Silicon dioxide SiO ₂ Lime CaO Melilites variable composition 23% 18% 1% 23% 5% 0% thirty%

In the description of this invention and in the appended claims, the singular forms include reference to the plural forms, unless the context dictates otherwise.

Unless otherwise indicated, all technical and scientific terms used in the invention have the meanings that are generally accepted by one of ordinary skill in the art. The invention describes the preferred methods and materials, but in the implementation or testing of the present invention can also be used in any methods and materials similar or equivalent to the methods and materials described in the invention. The methods specified in the invention can be carried out in any order that is logically possible, in addition to the order specifically specified in the invention.

Incorporation of the contents of a document into the invention by reference to it

In the description of this invention, references have been made and citations have been made to other documents such as patents, patent applications, patent publications, magazines, books, newspapers, Internet site content. The contents of all such documents, in all cases, are incorporated into the invention by reference to them. Any information or part of it, about which it is indicated that it is included in the invention by reference to it, but which contradicts the definitions, statements or other disclosures expressly set forth in the invention, is included in the invention only to the extent that there is no conflict between this included information and the information disclosed in the present invention. In the event of a conflict, the conflict must be resolved in favor of the present invention.

Equivalents

It is intended that the exemplary examples described in the invention are provided for the purpose of illustrating the invention only and should not be construed in any way as limiting the scope of the invention. Moreover, it will become apparent to those skilled in the art upon reading the full scope of the invention, including the examples provided in the invention and references to scientific and patent publications, that modifications of the invention and many additional embodiments beyond those shown and described in the invention. These examples contain important additional information, explanations and guidelines that can be used in the implementation of the present invention in practice in its various embodiments and equivalents.

Claims (14)

CLAIM 1. Composite material obtained by carbonization of calcium silicate with CO ₂ , including a plurality of binders and one or more filler materials, while these binders are elements of one or more types selected from: a binder comprising a silica core resulting from the carbonization of a carbonizable calcium silicate phase, completely or partially surrounded by a silica-rich crust layer of varying thickness, which is completely or partially enclosed in a shell of CaCO ₃ particles; - 17 040455 binder, comprising a core of silicon dioxide, formed as a result of carbonization having the ability to carbonize the phase of calcium silicate, completely or partially enclosed in a shell of particles of CaCO ₃ ; a binder comprising a core of non-carbonizable phase, completely or partially enclosed in a shell of particles of CaCO ₃ ; a binding element comprising a multiphase core consisting of silicon dioxide formed as a result of carbonization of a calcium silicate phase with the ability to carbonize, and partially reacted calcium silicate, where the multiphase core is completely or partially surrounded by a silica-enriched crust layer of various thicknesses, which is completely or partially enclosed into a shell of CaCO3 particles; a binder comprising a multi-phase core consisting of a non-carbonizable phase and partially reacted calcium silicate, where the multi-phase core is completely or partially surrounded by a silica-enriched crust layer of various thicknesses, which is completely or partially enclosed in a shell of CaCO3 particles; a binding element comprising particles of partially reacted calcium silicate without a clearly defined core and a crust layer of silicon dioxide enclosed in a shell of CaCO3 particles; and a binder comprising porous particles without a clearly defined crust layer of silicon dioxide, enclosed in a shell of CaCO ₃ particles, where a plurality of binders form a conjugated bonding matrix that provides adhesive strength and holds the composite material. 2. The composite material of claim 1 wherein the non-carbonizable phase is selected from silica and melilite. 3. A composite material according to claim 1 or 2, wherein the calcium silicate phase is selected from wollastonite, pseudowollastonite, rankinite, belite and carbonizable amorphous calcium silicates, or a combination of two or more of them. 4. Composite material according to any one of claims 1 to 3, further comprising one or more voids located in the space between the connecting elements, while optionally one or more connecting elements include one or more voids. 5. A composite material according to any one of claims 1 to 4, wherein the silica-enriched crust layer has a thickness in the range of from about 0.01 µm to about 50 µm. 6. A composite material according to any one of claims 1 to 5, wherein the silica-enriched crust layer is characterized by a silica content in the range of from about 50% to about 90% by volume and a CaCO ₃ content in the range from about 10% to about 50% by volume. volume. 7. Composite material according to any one of claims 1 to 6, wherein said one or more filler materials are optionally evenly distributed in the bond matrix. 8. A composite material according to any one of claims 1 to 7, further comprising one or more additional materials selected from fly ash, slag and fine silica dust, optionally evenly distributed in the binder matrix. 9. Connecting matrix, including a plurality of connecting elements, where the connecting elements are selected from: a binder comprising a silica core resulting from the carbonization of a carbonizable calcium silicate phase, completely or partially surrounded by a silica-rich crust layer of varying thickness, which is completely or partially enclosed in a shell of CaCO3 particles; a binder comprising a core of silicon dioxide formed as a result of carbonization having the ability to carbonize the phase of calcium silicate, and wholly or partially enclosed in a shell of CaCO ₃ particles; a binder comprising a core of non-carbonizable phase, fully or partially enclosed in a shell of particles of CaCO ₃ ; a binding element comprising a multiphase core consisting of silicon dioxide formed as a result of carbonization of a calcium silicate phase with the ability to carbonize, and partially reacted calcium silicate, where the multiphase core is completely or partially surrounded by a silica-enriched crust layer of various thicknesses, which is completely or partially enclosed into a shell of CaCO3 particles; a binder comprising a multi-phase core consisting of a non-carbonizable phase and partially reacted calcium silicate, where the multi-phase core is completely or partially surrounded by a silica-enriched crust layer of various thicknesses, which is completely or partially enclosed in a shell of CaCO3 particles; binding element, including particles of partially reacted calcium silicate without a clearly defined core and a crust layer of silicon dioxide enclosed in a shell of particles - 18 040455 CaCO3; and a binding element, including porous particles without a clearly defined crust layer of silicon dioxide, enclosed in a shell of particles of CaCO ₃ . 10. The binder matrix of claim 9 wherein the non-carbonizable phase is selected from silica and melilite. 11. The binding matrix according to claim 9 or 10, wherein the calcium silicate phase is selected from wollastonite, pseudowollastonite, rankinite, belite and carbonizable amorphous calcium silicates, or a combination of two or more of them. 12. A bonding matrix according to any one of claims 9 to 11, further comprising one or more voids located in the space between the bonding elements, optionally one or more of the bonding elements comprising one or more voids. 13. A bonding matrix according to any one of claims 9-12, wherein the silica-enriched crust layer has a thickness in the range of from about 0.01 µm to about 50 µm. 14. A bonding matrix according to any one of claims 9-13, further comprising one or more aggregate materials and optionally including one or more additional materials selected from fly ash, slag and fine silica dust.