Material for producing basic refractory products

Abstract

Presented and described is a material for producing basic refractory products, comprising, each based on the total weight of the material, 40 to 99 wt.% of a CaO-containing refractory component selected from the group consisting of sintered doloma, fused doloma, fused magdol, sintered magnesia, fused magnesia and a mixture thereof, 1 to 30 wt.% synthetic γ-dicalcium silicate (γ-C2S) and / or synthetic β-dicalcium silicate (β-C2S), wherein the synthetic γ-dicalcium silicate (γ-C2S) and / or β-dicalcium silicate (β-C2S) is produced from a mixture comprising CaO and SiO2 in a molar ratio of 2:1 to 2.5:1. Furthermore, the use of the material for producing shaped bodies or compositions as well as a method for producing a fired basic refractory shaped body are described.

Description

[0001] February 19, 2026

[0002] Material for the production of basic refractory products

[0003] The present invention relates to a material for the production of basic refractory products, the use of a material for the production of basic refractory products for the production of shaped bodies or masses, a method for the production of basic refractory shaped bodies and the use of a shaped body produced according to the method.

[0004] Refractory products typically comprise metallic, inorganic non-metallic, and / or carbon-containing compounds. They are highly relevant for lining industrial furnaces, particularly in high-temperature applications. Modern manufacturing processes and the long operating times required for production units in the steel and cement industries place high demands on the refractory products used. Consequently, the production of refractory products increasingly requires high-purity or synthetically produced raw materials, such as molten magnesia, molten magdol, sintered spinel, and molten spinel.

[0005] The production of fired bricks from the aforementioned raw materials requires a high proportion of direct bonding between the individual grains of the raw material mixture to ensure good high-temperature properties in the resulting products. For example, in fired magnesia bricks, the proportion of silicate bonding must be minimized, as the silicate bonding phase typically has a melting point below 1700 °C and would therefore negatively affect the bricks' high-temperature properties. Furthermore, fired bricks with a higher proportion of silicate bonds are often brittle and exhibit poor thermal shock resistance. Bricks such as fired doloma or magnesia-containing bricks are largely fired in tunnel kilns. Consequently, there are limited options for influencing the proportion of direct bonding. Besides adjusting the fineness of the powder used in the brickwork, the firing temperature can be increased, for example.However, with a fixed tunnel kiln length, this results in an increased exit temperature of the fired bricks. If the fired bricks have an excessively high temperature at the kiln exit, a thermal shock can occur, causing damage in the form of microcracks in the fired brick. Consequently, the physical properties, such as the stability of the fired brick, can be negatively affected. The fineness of the Doloma or Magnesia powder used in the brickwork is also limited due to the risk of hydration. In principle, the rate of hydration increases with increasing fineness of the powder.

[0006] Furthermore, the proportion of direct bonding in fired doloma- or magnesia-containing bricks can be increased by extending the residence time in the tunnel kiln. However, this reduces the kiln's production capacity and can simultaneously decrease the dimensional stability of the fired bricks. Due to sintered dolomite's tendency to react with atmospheric moisture (hydration), rapid firing of the bricks after pressing is essential. Conversely, extended residence times in the tunnel kiln can lead to longer intervals between pressing and firing, during which the pressed, unfired bricks are exposed to environmental influences. The risk, or even the degree, of hydration in the sintered dolomite increases with increasing time, depending on temperature and humidity.

[0007] In the production of fired bricks containing doloma or magnesia, silicon dioxide (SiCh)-rich clay or fine SiCh (silica fume) is usually added to the doloma-containing flour before pressing and firing. However, the proportion of silica-rich clay is limited, as higher quantities of alumina are too low.

[0008] 231094WO RT / ts February 19, 2026 Melting compounds can form within the stone. Furthermore, the addition of SiO2 carries the risk of incomplete conversion to tricalcium silicate (C3S) during the firing process. Some of the silicon dioxide can react to form dicalcium silicate (C2S), which can damage the stone through a volume change during the β-γ decomposition of C2S. Additionally, SiO2 can react with MgO to form magnesium metasilicate (MgSiOs). At temperatures above 1550 °C, the magnesium metasilicate is liquid within the stone and can undergo further unwanted chemical reactions. Upon cooling, it eventually remains as a glassy phase within the stone, making it brittle. Therefore, the SiO2 content should not typically exceed 2% by weight.

[0009] Carbon-bonded refractory products, such as molded parts or masses made from high-purity doloma- or magnesia-containing raw materials, can also exhibit increased wear. This is because decarburization often occurs at elevated temperatures, and the grains of the doloma- or magnesia-containing main component are sometimes unable to form a stable bond before steel or slag penetrates the resulting pore structure. Consequently, entire grains of the doloma- or magnesia-containing main component are absorbed by the steel and slag, or the pore space fills with steel or slag. The infiltrated slag leads to chemical corrosion in the infiltrated zone, which often spalls off during temperature changes. This results in increased wear and thus a reduction in the service life of the lining.

[0010] The object of the invention was therefore to provide a material for the production of basic refractory products that at least partially overcomes one or more disadvantages of the prior art. The material should be easy to process and shape. Basic refractory products manufactured from the material should exhibit good high-temperature properties. Essentially, basic refractory products made from the material should have increased durability, particularly compared to conventional carbon-bonded and / or silicon dioxide-containing metal oxide refractories.

[0011] 231094WO RT / ts February 19, 2026. The material should be suitable for the production of basic refractory products with a high degree of direct bonding. In particular, the material should be suitable for the production of products in the form of molded parts or masses. Such molded parts or masses should be suitable for use in equipment of the iron and steel industry where liquid iron or steel is produced and processed, and / or for lining rotary kilns and shaft kilns in the lime and cement industry. The molded parts and masses should contribute to reduced wear of the aforementioned equipment. Furthermore, the material should be easy to transport. In particular, it should be easy to process further into the desired products at the end customer's site.

[0012] A further object of the present invention is to provide a method for producing a refractory basic molded body with the described properties. In particular, the method should be efficient and applicable to mass production.

[0013] All or some of these problems are solved according to the invention by a material for the production of basic refractory products according to claim 1, by a use according to one of claims 9, 10 and 13-16 and by a method according to claim 12.

[0014] Advantageous embodiments of the invention are specified in the dependent claims and are explained in detail below.

[0015] The invention provides a material for the production of basic refractory products, comprising

[0016] 40 to 99 wt.% of a resistor containing CaO, selected from the group consisting of sintered doloma, melting doloma, melting magdol, sintered magnesia and a mixture thereof, in particular sintered doloma, melting doloma or a mixture thereof,

[0017] 231094WO RT / ts 19 February 20261 to 30 wt.% synthetic γ-dicalcium silicate (Y-C2S) and / or synthetic β-dicalcium silicate (β-C2S),

[0018] wherein the synthetic y-dicalcium silicate (Y-C2S) and / or β-dicalcium silicate (β-C2S) is prepared from a mixture comprising CaO and SiO2 in a molar ratio of 2:1 to 2.5:1.

[0019] When sintered dolomite or melted dolomite is mentioned here or elsewhere, unless otherwise stated, this refers to dolomite (CaOMgO) obtained by sintering or melting dolomite (CaMg[CO3]2).

[0020] When sintered magnesia or fused magnesia is mentioned here or elsewhere, unless otherwise stated, this refers to magnesia (MgO) obtained by sintering or melting magnesite (MgCOs) and containing at least 0.5 wt.% CaO.

[0021] When Schmelzmagdol is mentioned here or elsewhere, unless otherwise stated, it refers to a mixture of Doloma (CaOMgO) and Magnesia (MgO) in which the MgO content is at least 50 wt.%.

[0022] When a high-temperature range, high temperatures, or high-temperature properties are mentioned here or elsewhere, the application temperature refers to a temperature greater than 1300 °C, unless otherwise specified.

[0023] In principle, the term refractory should not be limited within the scope of the invention to the definition according to DIN 51060 or ISO 836, according to which materials that have a Seger cone falling temperature of >1500 °C are considered refractory.

[0024] Rather, the term "refractory" refers to products used to protect aggregate structures in aggregates where temperatures are between 1000 °C and 2000 °C, in particular between 1200 °C and 1800 °C.

[0025] 231094WO RT / ts February 19, 2026 This document uses standard cement notation unless otherwise stated. C stands for CaO. S stands for SiO2. Consequently, dicalcium silicate is represented as C2S, since it has a molar calcium-to-silicon ratio of 2:1. This corresponds to the conventional notation Ca2SiO4, which is also represented as 2CaO-SiO2. Similarly, tricalcium silicate (C3S) has a molar calcium-to-silicon ratio of 3:1. This corresponds to the conventional notation CasSiOs, which is also represented as 3CaO-SiO2.

[0026] Surprisingly, it has been found that basic refractory products with excellent high-temperature properties can be manufactured in a particularly simple manner using the material according to the invention. In particular, basic refractory products can be manufactured from the material according to the invention that exhibit reduced wear due to heat exposure compared to conventional carbon-bonded and / or silicon dioxide-containing metal oxide refractory products. The material according to the invention is easy to process and can be easily shaped, for example, by compression. Furthermore, the material can be easily filled. Thus, it can be easily transported to the end customer for further processing.

[0027] Surprisingly, it has been found that by using a CaO-containing resistor selected from the group consisting of sintered doloma, melted doloma, melted magdol, sintered magnesia, melted magnesia, and a mixture thereof, in combination with 1 to 30 wt.% synthetic y-C₂S and / or synthetic β-C₂S, a material can be obtained that is suitable for the production of basic refractory products exhibiting particularly high heat resistance and robustness. In particular, a basic refractory product with a particularly high degree of direct bonding can be produced from the material according to the invention. Furthermore, refractory products can be produced from the material according to the invention that can be used in aggregates of the iron, steel, cement, or lime industries for lining high-temperature zones. Such use of the material according to the invention can reduce wear.

[0028] 231094WO RT / ts February 19, 2026 The refractory linings are reduced, thus extending the service life of the units. The high robustness of the material allows for longer maintenance intervals and cost savings.

[0029] Without wishing to be bound to a specific scientific theory, the surprising effect seems to be explained by the fact that the use of Y-C₂S and / or β-C₂S introduces a second high-temperature bonding phase into the products consisting of the material according to the invention. In this process, Y-C₂S and / or β-C₂S react with the CaO contained in the resistor to form C₃S.

[0030] (Tm = 2150 °C) and forms a bond that remains stable even at application temperatures above 1400 °C. The second high-temperature bonding phase can form either during the manufacture of a product from the material according to the invention or during the use of a product manufactured from the material. This second bonding phase improves the physical properties, including the high-temperature properties, of a product made from the material, thus increasing its durability.

[0031] Surprisingly, it has been found that synthetic Y-C₂S and / or β-C₂S, produced from a mixture comprising CaO and SiO₂ in a molar ratio of 2:1 to 2.5:1, is particularly well suited for the incorporation of a second high-temperature binder phase. Besides Y-C₂S and β-C₂S, other polymorphs of C₂S exist, such as C₇C₂S, H-C₂S, and L-C₂S. Non-synthetically produced Y-C₂S and / or β-C₂S, which occurs, for example, in Portland cement or slag, often contains impurities, particularly in the form of other C₂S polymorphs. Furthermore, Y-C₂S and / or β-C₂S cannot be readily extracted from Portland cement or slag. Therefore, non-synthetically produced Y-C₂S and / or β-C₂S is not suitable for the material according to the invention, which requires a higher degree of purity.It has also been shown that a molar ratio of CaO to SiO2 of 2:1 to 2.5:1 is particularly suitable for obtaining synthetic Y-C2S and / or β-C2S with high purity. A lower molar ratio, on the other hand, can predominantly lead to the formation of calcium silicate (CS).

[0032] 231094WO RT / ts February 19, 2026. A higher molecular ratio can predominantly lead to the formation of C3S.

[0033] Resistor

[0034] The material according to the invention for the production of basic refractory products contains a resistor.

[0035] When a resistor is mentioned here or elsewhere, unless otherwise stated, it refers to the mineral, metal oxide-containing main component of the material used to manufacture basic refractory products.

[0036] Preferably, the resistor contains a CaO content of at least 10 wt.%, in particular at least 20 wt.%, more preferably at least 30 wt.%, and further preferably at least 40 wt.%. Such a proportion is particularly well suited to incorporating a second high-temperature binder phase into the refractory material and thus ensuring high heat resistance and robustness. Lower amounts of CaO, on the other hand, could lead to reduced fire resistance.

[0037] According to a preferred embodiment of the invention, the material contains 50 to 98 wt.%, in particular 60 to 98 wt.%, and more preferably 70 to 97 wt.% of the resistor. The resistor plays a crucial role in the refractoriness of the product. Such a high proportion of the resistor allows for the production of a particularly stable refractory product. A higher proportion can lead to a brittle and / or wear-prone material. A lower proportion of the resistor can lead to reduced refractoriness.

[0038] Preferably, the resistor has a maximum grain size of 8 mm, particularly 5 mm, and a grain size distribution corresponding to a typical Fuller curve. The grain size is preferably determined by sieve analysis.

[0039] 231094WO RT / ts February 19, 2026 In a further preferred embodiment of the material according to the invention, the resistor comprises a binder, in particular a binder selected from the group consisting of paraffins and / or waxes, pitch and / or pitch-based binders, resol resins, phenolic resins, and a mixture thereof. Such a binder can contribute to improving the strength of the material and promote a homogeneous structure. A homogeneous structure makes it easier to form the material into the desired shape. A homogeneous structure is particularly advantageous if the product manufactured from the material is a molded body that is initially produced by pressing the material.

[0040] Examples of binders are Carborees® from Rain Carbon Inc. or hard paraffins from H&R Wax & Specialties GmbH.

[0041] Dicalcium silicate

[0042] According to a preferred embodiment of the invention, the material contains, based on the total weight of the material, 1 to 25 wt.%, in particular 1 to 20 wt.%, preferably 1 to 15 wt.%, synthetic Y-C₂S and / or β-C₂S. Such a proportion of Y-C₂S and / or β-C₂S allows for the excellent formation of a second high-temperature bonding phase, which imparts increased wear resistance to a refractory product manufactured from the material. A higher proportion of Y-C₂S and / or β-C₂S could negatively affect the physical properties of the product and / or significantly increase the cost of the material. A lower proportion of Y-C₂S and / or β-C₂S would reduce the proportion of direct bonding by the second high-temperature bonding phase and shorten the durability of the product.

[0043] The synthetic Y-C2S and / or β-C2S is preferably obtained from a mixture of CaO and SiO2 by melting in an electric furnace with a tilting device. This type of furnace allows for very good separation of non-conforming or only partially conforming components.

[0044] 231094WO RT / ts February 19, 2026 molten CaO or S1O2 from the final product. This allows for the achievement of high purity of Y-C2S and / or β-C2S. This is particularly important in the production of Y-C2S, as it decomposes into dust during the cooling process and consequently can no longer be separated from any entrained CaO or SiO2. Furthermore, such a production process enables the production of large quantities of Y-C2S and / or β-C2S, which are necessary to meet the demand as raw materials for the manufacture of basic refractory products.

[0045] Preferably, 0.01 to 5 wt.%, in particular 0.05 to 3 wt.%, and more preferably 0.1 to 1.5 wt.%, of B₂O₃ is added to the mixture of CaO and SiO₂ before melting, based on the total weight of the mixture. The B₂O₃ can contribute to the stabilization of Y-C₂S and / or β-C₂S. In particular, the β-C₂S formed can thus be stabilized to prevent decomposition with dust formation, which can occur when the melt cools.

[0046] The mixture preferably contains CaO and SiO2 with a particle size (Dgo value) of less than 5 mm. The particle size is determined in particular by sieve analysis.

[0047] According to a further preferred embodiment of the invention, the CaO and SiO2 used for the production of synthetic Y-C₂S and / or β-C₂S have a purity of at least 97 wt.% each. Y-C₂S and / or β-C₂S can thus be produced in particularly high purity. This can have a positive effect on the second high-temperature bonding phase and therefore on the refractoriness of a product manufactured from the material.

[0048] use

[0049] The material according to the invention is suitable for various uses.

[0050] The invention relates to the use of a material according to the invention for the production of shaped bodies or masses, which are used particularly in aggregates of

[0051] 231094WO RT / ts February 19, 2026 The iron and steel industry, in which liquid iron or steel is produced and processed, is used. In particular, the shaped bodies or masses can be used on the refractory side or as an internal lining of the equipment. Such use has the advantage of ensuring high refractoriness. In contrast to conventional carbon-bonded and / or silicon dioxide-containing metal oxide refractory products, the use according to the invention further has the advantage that shaped bodies or masses with lower wear potential are available. Thus, maintenance intervals can be extended and operating costs of the equipment can be reduced.

[0052] The invention further relates to the use of a material according to the invention for the production of molded parts or masses used for lining rotary kilns and shaft kilns in the lime and cement industry. In particular, this can involve an inner or fire-side lining. Such use has the advantage that, in addition to good mechanical and thermal properties, the molded parts or masses offer good flexibility. In contrast, molded parts and masses made of refractory materials such as pure magnesia can exhibit disadvantages due to their high brittleness when used in rotating devices such as rotary kilns. This can manifest itself in increased wear. Conversely, the use according to the invention can contribute to a longer service life of the lining.

[0053] The invention further relates to the use of a material according to the invention in which the material is first filled into suitable packaging and introduced into the appropriate units by tamping, shaking, or vibration. The advantage of such use is that the end customer can independently shape the material as desired and thus has a high degree of flexibility in shaping. Such use is possible because the material according to the invention is easy to transport and shape.

[0054] 231094WO RT / ts February 19, 2026 Procedure

[0055] Another object of the present invention is a method for producing a refractory basic molded body comprising the steps of:

[0056] a] Providing a material according to the invention for the production of basic refractory products;

[0057] b] Compressing the material from a] at a specific pressing pressure greater than 50 MPa, in particular at a specific pressing pressure of 100 to 200 MPa; c] Firing the material compressed in step b] at a temperature greater than 1250 °C, in particular at a temperature of 1450 to 1800 °C.

[0058] The above applies analogously to the refractory basic molded body and the material according to the invention for the production of basic refractory products.

[0059] The process according to the invention enables the particularly efficient production of basic refractory components. Furthermore, such a process enables the production of basic refractory components that exhibit good high-temperature properties. In particular, the process according to the invention can produce a basic refractory component that can exhibit increased durability compared to conventional carbon-bonded and / or silicon dioxide-containing metal oxide refractory products.

[0060] By compressing the material according to the invention at a specific pressing pressure greater than 50 MPa, and in particular at a specific pressing pressure of 100 to 200 MPa, the desired shape of the molded body is obtained. A lower pressing pressure would lead to an unstable molded body, as the individual grains of the material would not be densely packed. Consequently, the molded body may exhibit increased porosity and be more susceptible to infiltration by liquid products, for example, by liquid iron.

[0061] 231094WO RT / ts February 19, 2026 Firing the material pressed in step b] at a temperature above 1250 °C, particularly at a temperature of 1450 to 1800 °C, results in the formation of a second high-temperature binder phase. During firing, calcium oxide contained in the resistor reacts with γ-C₂S and / or β-C₂S to form C₃S. This constitutes the second high-temperature binder phase in the molded part and is stable even at application temperatures above 1400 °C. The firing process thus improves the physical properties, including the high-temperature properties, of the molded part and increases its durability. At a lower firing temperature, however, the formation of the second high-temperature binder phase may not occur or may be incomplete.

[0062] It is advantageous to carry out steps a] to c] one after the other.

[0063] Preferably, the pressed material from step b] is thermally treated before firing in step c] at an annealing temperature below 900 °C, particularly at a temperature of 200 to 750 °C. This thermal treatment is also referred to as annealing. The thermal treatment increases the mobility of the molecules. As a result, stresses in the crystal lattice of the materials used can be eliminated and the structure optimized, ultimately increasing the stability and refractoriness of the basic molded body.

[0064] What has been said in connection with the method for producing a refractory basic molded body also applies to the material according to the invention for producing basic refractory products.

[0065] The refractory basic molded body according to the invention is suitable for various uses.

[0066] The invention further relates to the use of a method according to the invention for the production of a refractory shaped body, in particular for

[0067] 231094WO RT / ts February 19, 2026 Production of a refractory brick. Such use has the advantage that a refractory body, and in particular a refractory brick, with excellent physical properties can be produced. Through such use, refractory bodies, and in particular refractory bricks, can be produced that exhibit, in particular, higher durability compared to conventional carbon-bonded and / or silicon dioxide-impregnated metal oxide refractory bodies.

[0068] The invention further relates to the use of a shaped body produced according to a method according to the invention in units of the iron and steel industry in which liquid iron or steel is produced and processed, or in rotary kilns and shaft kilns of the lime and cement industry. Such use has the advantage that the wear of the refractory lining can be reduced. Consequently, maintenance intervals can be extended and costs reduced. Furthermore, such use has the advantage that the use of such a shaped body can also take place in rotating devices such as rotary kilns. In particular, the shaped body can be used as an inner or fire-side lining. The shaped body can also be used as a working lining.

[0069] What has been said in connection with the use of the material according to the invention for the production of basic refractory products also applies to the use of a molded body produced according to a method according to the invention and vice versa.

[0070] Example of implementation

[0071] A material for the production of basic refractory products was manufactured according to the composition shown in Table 1. The quantities used refer to the total weight of the composition. Example 1 is a comparison example without the addition of C₂S.

[0072] 231094WO RT / ts February 19, 2026 Table 1: Composition

[0073] Component Grain Size* Example 1 (Comparison) Example 2

[0074] [mm] [percentage by weight] [percentage by weight] Doloma flour 0 – 0.2 18.7 13

[0075] C2S (synthetic) 0 – 0.09 5.6 Doloma 0 – 1 37.3 37.3 Doloma 1 – 3.15 42.2 42.2 Binder 1.8 1.8

[0076]

[0077] *Determined by sieve analysis

[0078] Table 2 shows the physical properties of a molded body with and without the addition of C₂S. Molded bodies (cylinders with a radius of 50 mm and a height of 50 mm) were produced by non-axial compression of the composition shown in Table 1 at a pressure of 175 MPa. Subsequently, the molded bodies were fired at 1550 °C in a laboratory furnace (adhesion time at 1550 °C for 6 h).

[0079] For the investigation of bulk density, open porosity, and cold compressive strength, standard specimens with a radius of 36 mm and a height of 36 mm were produced by drilling and grinding. For the determination of refractoriness under load (RuL test), shaped specimens with a radius of 50 mm and a height of 50 mm were used.

[0080] 231094WO RT / ts February 19, 2026 Table 2: Measured parameters

[0081] Parameters for fired Doloma molded bodies Example 1 (comparison) Example 2 Bulk density (green density) R1 2.70 2.70 [g / cm³] 3 ]

[0082] Bulk density when fired (2.79–2.82 density) R3 [g / cm³] 3 ]

[0083] Open porosity [%] 15.5 14.5 Cold compressive strength [MPa] 87.54 159.2

[0084] RuL T 05 [°C] 1560 1630

[0085]

[0086] The values ​​shown in Table 2 demonstrate that a basic refractory product can be obtained using the composition according to the invention, exhibiting a similar bulk density and open porosity to a product that does not contain C₂S. Surprisingly, it has been found that the material according to the invention can be used to produce a product with increased cold compressive strength. Thus, a product made from the material according to the invention exhibits high stability and durability. The material is therefore also suitable for products that must withstand increased physical forces and can contribute to a reduction in wear. At the same time, the material can be easily shaped.

[0087] Furthermore, the composition according to the invention yields a basic refractory product with pronounced high-temperature properties. A molded body produced from the composition according to the invention exhibits high refractoriness under load.

[0088] 231094WO RT / ts February 19, 2026

Claims

February 19, 2026 patent claims 1. Material for the manufacture of basic refractory products, comprising, in each case based on the total weight of the material, 40 to 99 wt.% of a resistor containing CaO, selected from the group consisting of sinterdoloma, molten doloma, molten magdol, sintered magnesia, molten magnesia and a mixture thereof, 1 to 30 wt.% synthetic γ-dicalcium silicate (γ-C2S) and / or synthetic β-dicalcium silicate (β-C2S), wherein the synthetic γ-dicalcium silicate (γ-C2S) and / or β-dicalcium silicate (β-C2S) is prepared from a mixture comprising CaO and SiO2 in a molar ratio of 2:1 to 2.5:

1.

2. Material for the production of basic refractory products according to claim 1, characterized in that the material contains, in each case based on the total weight of the material, 50 to 98 wt.%, in particular 60 to 98 wt.%, more preferably 70 to 97 wt.% of the resistor.

3. Material for the production of basic refractory products according to claim 1 or 2, characterized in that the material contains, in each case based on the total weight of the material, 1 to 25 wt.%, in particular 1 to 20 wt.%, preferably 1 to 15 wt.% synthetic γ-dicalcium silicate (γ-C2S) and / or β-dicalcium silicate (β-C2S).

4. Material for the production of basic refractory products according to one of the preceding claims, characterized in that the resistor has a maximum grain size of 8 mm, in particular 5 mm, and a grain size distribution corresponding to a typical Fuller curve.

5. Material for the production of basic refractory products according to one of the preceding claims, characterized in that the resistor contains a binder, in particular a binder selected from the group consisting of paraffins and / or waxes, pitch and / or pitch-based binders, resol resins, phenolic resins, and a mixture thereof.

6. Material for the production of basic refractory products according to one of the preceding claims, characterized in that the synthetic y-dicalcium silicate (Y-C2S) and / or β-dicalcium silicate (β-C2S) is obtained from a mixture of CaO and SiO2 by melting in an electric furnace with a tilting device.

7. Material for the production of basic refractory products according to claim 6, characterized in that 0.01 to 5 wt.%, in particular 0.05 to 3 wt.%, preferably 0.1 to 1.5 wt.% B2O3, in each case based on the total weight of the mixture of CaO and SiO2, are added to the mixture of CaO and SiO2 before melting.

8. Material for the production of basic refractory products according to one of the preceding claims, characterized in that the material used to produce synthetic γ-dicalcium silicate (γ-C₂S) and / or β-Dicalcium silicate (β-C2S) used CaO and SiO2 has a purity of at least 97 wt.% each.

9. Use of a material according to any one of claims 1 to 8 for the production of shaped bodies or masses, which are used in particular in aggregates of the iron and steel industry in which liquid iron or steel is produced and processed.

10. Use of a material for the production of basic refractory products according to any one of claims 1 to 8 for the production of shaped bodies or 231094WO RT / ts 19 February 2026 Masses used for lining rotary kilns and shaft kilns in the lime and cement industry.

11. Method for producing a fired refractory basic body comprising the steps a] Providing a material for the production of basic refractory products according to any one of claims 1 to 8; b] Compressing the material from a] at a specific pressing pressure greater than 50 MPa, in particular at a specific pressing pressure of 100 to 200 MPa; c] Burning the material compressed in step b] at a temperature greater than 1250 °C, in particular at a temperature of 1450 to 1800 °C.

12. Method for producing a carbon-bonded refractory basic shaped body comprising the steps a] Providing a material for the production of basic refractory products according to any one of claims 1 to 8; b] Compressing the material from a] at a specific pressing pressure greater than 50 MPa, in particular at a specific pressing pressure of 100 to 200 MPa; c] Tempering of the material thermally treated in step b] at a temperature below 900 °C, in particular from 200 to 750 °C.

13. Use of a method according to claim 11 or 12 for the production of a refractory shaped body, in particular for the production of a brick.

14. Use of a molded body produced according to claim 11 or 12 in aggregates of the iron and steel industry in which liquid iron or steel is produced and processed, or in rotary kilns and shaft kilns of the lime and cement industry. 231094WO RT / ts February 19, 2026 15. Use of a material for the production of basic refractory products according to one of claims 1 to 8, wherein the material is first filled into a suitable packaging and introduced into the appropriate units by tamping, shaking or vibrating.

16. Use of a mixture produced according to claim 15 in aggregates of the iron and steel industry in which liquid iron or steel is produced and processed, or in rotary kilns and shaft kilns of the lime and cement industry. 231094WO RT / ts February 19, 2026

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