CALCINED KAOLIN
Calcined kaolin is an anhydrous aluminum silicate produced by heating natural kaolin to high temperatures, which increases hardness and alters particle shape.
Calcined kaolin, also known as metakaolin, is highly valued in construction and ceramics for its improved strength, whiteness, and thermal stability.
The calcination process of kaolin at temperatures above 980°C forms fully calcined products with an amorphous spinel structure, enhancing their suitability as fillers in various industrial applications.
CAS Number: 1332-58-7
EC Number: 215-286-9
Molecular Formula: Al2Si2O7
Molecular Weight: 258.16 g/mol
Synonyms: Cal Kaolin, Meta Kaolin, Kaoline, Polestar 200R, Calcined kaolin, Calcination kaolin, Calcined kaolin, Kaolin,calcined, Satintone 1, M 100 (clay), Tuboryl N, PoleStar 200R, Nuopaque, Ansilex 90, Alphatex, Satintone Special, M 100, Satintone Whitetex, Satintone 5, Ansilex 93, Deltatex, Kaocal, Satintone SP 33, SP 33, Satintone, Ansilex, Satintone W/W, Satintone W, Glomax LL, Molochite, Altowhite TE, SP33 (clay), Whitetex, PoleStar 200P, Hycal, Satintone 5HB, PoleStar 400, Satintone 100, PD 30, PD 30 (clay), Metasial C, Hubertex, M 02-023, MXK 101, MXK 201, MXK 301, MXK 402, AT 01, MXK 401, AT 01 (clay), Polyfil WC, Huber 2000C, 2000C, 2000C (clay), G 1002, Kaocal 50, Metabrite CM 70, MXK 201A, Britex 98, Huber 80C, BM-V 60, HS 801A, Baixue 90, AGX 19, AGX 19BM, MKo (clay), MKo, HY-T 80, DB 80, HA 90, MXK 101A, K 88, K 88 (clay), CK 400, Liteball 14/40, Omyacarb 10LU, BR 95, BR 95 (clay), HPF 400, DG 80, TZJ 1, Kaopolite 1168, JYB 60, YD-A 2, Burgess CB, GY 915, KO 0298, Satintone Clay 5A, KaMinTex, JYQK 95, MIKAO 98-02, Jingyang BR 80, BR 80, Huber 100C, NCCP 1000, Britex 95, Britex 96, KaMin 100C, P 200R, C 98, JYA 15, SX 80A, MKX 201, DG 95, G 311, KB 250, 39388-40-4, 1505447-37-9, 1505447-47-1, 1505447-71-1
Calcined kaolin is produced when raw kaolin or more popularly known as Clay or China Clay is fired enough to reduce its crystalline water content via a process known as Calcination.
Calcined kaolin is an anhydrous aluminium silicate produced by heating natural china clay to high temperatures in a kiln.
This calcination process gives an increase in hardness and alters the particle shape of the kaolin.
When calcination occurs at around 700°C, the dehydroxylation of the kaolin is complete, forming a partially crystalline metakaolin.
Fully calcined products with an amorphous defect spinel structure are formed above 980°C.
Fully Calcined kaolin can be treated with silane to give a particle surface capable of chemically coupling with the polymer.
Kaolin is one of the most indispensable fillers in the paint industry; a natural clay raw material, containing Ca and Na.
Calcined kaolin is a raw material characterized by kaolinite mineral.
In industrial use, Calcined kaolin is included as calcined in the production part under kaolin.
The raw materials in which kaolinite is enriched and used in kaolinitic and others are included in clay raw materials.
The brightness, corrosivity, viscosity and grain size distribution- max grain size-shape and the rheology (water + clay behavior) of these kaolins are very important.
All these properties are determined by the conditions of formation of kaolin and improved by post-production processes.
Calcined kaolin or Calcined Clay is also called as Metakaolin or Chamotte.
Calcined kaolin is an anhydrous aluminium silicate, a white powdered non-plastic material.
Calcined kaolin which is a hydrous, thermally structured aluminum silicate, produced by heating ultra-fine natural kaolin at a very high temperature.
The calcination process changes the shape of kaolin particle and increases its hardness.
During the calcination process of kaolin, dehydroxylation takes place and leads to the formation of METAKAOLIN, which is a highly reactive substance.
When kaolin is completely calcined, Calcined kaolin leads to the formation of an amorphous defect spinal structure, which helps to contribute opacity to end product application.
Calcined kaolin can also be used to replace and substitute TiO2 from 15 to 25%, in a number of applications.
Calcined kaolin has a low surface hydroxyl content which leads to low moisture pick up.
Therefore, Calcined kaolin performs excellently in moisture sensitive applications.
Calcined kaolin is refractory and softens at about cone 35.
Calcined kaolin is thus useful in refractory castables and furniture, thermal insulation bodies, low expansion bodies, permeable ceramic compositions, and investment casting.
If you are a potter you can make your own Calcined kaolin by simply bisque firing any raw powdered kaolin (in a small enough bisque vessel and slow enough ramp that the heat penetrates well).
Actually, roasting the powder at red heat is sufficient to destroy the plasticity.
The material is a good example of how we can alter the mineralogy of a material to affect Calcined kaolin's working properties while maintaining the chemistry to retain fired properties.
Calcined kaolin is produced by calcining (firing, sintering) kaolin clay or kaolinite rock (flint clay).
Calcination is mainly carried out in rotary kilns, but also in shaft kilns, ring kilns and tunnel kilns.
There are chamottes with different alumina contents and correspondingly different refractoriness.
Depending on the chemical composition, different levels of corrosion and acid resistance are achieved.
Fireclay can be supplied as a raw material in a fineness of 0 to 25 mm or 0 to 50 mm, but also in finished refractory grain sizes and finenesses.
Calcined kaolin is often under-utilized in traditional ceramics.
Kaolin is pure clay mineral, having a fired chemistry of 1 part Al2O3 and 2 parts SiO2.
But the raw Kaolin clay crystals are hydrated, with 12% crystal-bound water.
This is the secret to their plasticity.
Calcined kaolin is essential to the chemistry of the vast majority of glazes and kaolin is ideal source material (because all glazes also need the SiO2 that Calcined kaolin supplies and it readily decomposes in the melt).
The other principle affordable and readily meltable supplier of Al2O3 are feldspars, however they also supply lots of KNaO (and in many cases oversupply Calcined kaolin to get the needed Al2O3).
Raw Kaolin also supplies suspension to the glaze slurry and it hardens the dry glaze layer.
However once raw kaolin percentages pass 20% in a recipe shrinkages can be to high (causing crawling).
In these cases substituting part of the raw kaolin for calcined material solves the problem, maintaining the chemistry of the glaze but reducing the shrinkage and cracking.
In other words, by substituting some of the raw kaolin for calcined the physical properties of the glaze slurry can be controlled without impacting the chemistry of the fired melt.
Of course, mixing the raw and calcined materials must take into account the LOI of the raw material (12% less calcined is needed).
Calcined kaolin is a powdered white non-plastic material.
Calcined kaolin is raw kaolin which has been fired (in a rotary calcining kiln) high enough to remove the 12% (approx) crystal water.
Calcined kaolin is a good example of how we can alter the mineralogy of a material to affect its working properties while maintaining the chemistry to maintain fired properties.
The process by which Kaolin clay material is processed (approximately 1400 degrees C) creates what is known as Calcined kaolin (chamotte).
Have you ever thought about the white, powdery substance that’s used in everything from ceramics and paper to paint and coatings?
You may be surprised to learn that it’s actually known as Calcined kaolin powder, a versatile material with a wide range of unique properties.
From Calcined kaolin's thermal stability to its particle size distribution, this substance is a game-changer in multiple industries.
So, buckle up and get ready to dive into the world of Calcined kaolin powder and discover its significance in various applications that may surprise you!
Calcined kaolin is a white clay-like mineral widely used for paper and ceramics.
Despite its similarities, Calcined kaolin undergoes a unique process to achieve its unique properties.
The process involves heating the kaolin to a high temperature, which alters its chemistry, making Calcined kaolin more suitable for various applications.
Calcined kaolin is a powdered white non-plastic material.
Calcined kaolin is raw kaolin that has been fired (in a rotary calcining kiln) high enough to remove the crystal water.
Calcined kaolin is useful in tuning the shrinkage and plasticity of slips (engobes) which are applied to wet, leather hard or dry ware.
Calcined kaolin is an anhydrous aluminium silicate produced by heating ultrafine natural kaolin to high temperatures in a kiln.
The calcination process increases whiteness and hardness, improves electrical properties, and alters the size and shape of the kaolin particles.
Calcined kaolin are produced from highly refined kaolin through grind, calcination and Classification.
Calcined kaolin has high purity and the quality is stabled.
Calcined kaolin offers superfine particle and with excellent anti-settling property.
Calcined kaolin can easily disperse in water based systems.
Calcined kaolin is inert to most acids and alkaline at Ambient temperature and offers good anticorrosive capabilities.
Calcined kaolins are fired to a temperature high enough to effect loss of crystal water (and accompanying mineral change).
Calcined kaolin normally converts to mullite during this process.
Calcined kaolin is valuable in glaze formulations that contain high amounts of kaolin to source alumina, and which are thus subject to shrinkage and cracking-during-drying problems.
By substituting some of the raw kaolin for calcined (such as Glomax), the physical properties of the glaze slurry can be controlled without impacting the chemistry of the fired melt.
Mixing the two materials must of course take into account that raw kaolin has a 14-15% loss on ignition (or LOI) that the calcined material does not.
Calcined kaolin, also known as Metakaolin, is a processed form of kaolin clay that has been heated at high temperatures (typically between 600 and 800 degrees Celsius) to remove water and other volatile compounds.
This calcination process alters the physical and chemical properties of kaolin, making Calcined kaolin suitable for various applications in the construction industry.
Calcined kaolin is also useful in tuning the shrinkage and plasticity of slips which are applied to wet, leather hard or dry ware.
Because their shrinkage is very low, they can be substituted for part of the regular kaolin and there will likewise be minimal impact on the fired properties.
Calcined kaolin has a variety of other uses in products including paint, rubber, cable insulation, specialty films and fertilizers.
Calcined kaolin is made from kaolin material.
Kaolin divided into from industry: Hard kaolin, Soft kaolin, Sandy clay.
Calcined kaolin is calcined to a certain temperature deep-processing products in the calciner.
Calcined kaolin is calcined during dehydration and the volatiles were removed.
Fired at different temperatures with different physical properties.
Calcined kaolin is mainly used for manufacturing high-quality refractory products, refractory castable, sagger, firebrick, kiln furniture, crucibles, ceramic fiber, precision casting sand, ceramics products, etc.
Calcined kaolin can easily disperse in water based systems.
Calcined kaolin is produced by calcining (firing, sintering) kaolin clay or kaolinite rock (flint clay).
Calcination is mainly carried out in rotary kilns, but also in shaft kilns, ring kilns and tunnel kilns.
There are chamottes with different alumina contents and correspondingly different refractoriness.
Depending on the chemical composition, different levels of corrosion and acid resistance are achieved.
Fireclay can be supplied as a raw material in a fineness of 0 to 25 mm or 0 to 50 mm, but also in finished refractory grain sizes and finenesses.
Calcined kaolins are fired to a temperature high enough to effect loss of crystal water (and accompanying mineral change).
Calcined kaolin normally converts to mullite during this process.
Calcined kaolin is valuable in glaze formulations that contain high amounts of kaolin to source alumina, and which are thus subject to shrinkage and cracking-during-drying problems.
By substituting some of the raw kaolin for calcined (such as Glomax), the physical properties of the glaze slurry can be controlled without impacting the chemistry of the fired melt.
Mixing the two materials must of course take into account that raw kaolin has a 14-15% loss on ignition (or LOI) that the calcined material does not.
Calcined kaolins are also useful in tuning the shrinkage and plasticity of slips which are applied to wet, leather hard or dry ware.
Because their shrinkage is very low, they can be substituted for part of the regular kaolin and there will likewise be minimal impact on the fired properties.
Kaolin Powder is a white clay-like mineral widely used for paper and ceramics.
Despite its similarities, Calcined kaolin Powder undergoes a unique process to achieve its unique properties.
The process involves heating the kaolin to a high temperature, which alters its chemistry, making Calcined kaolin more suitable for various applications.
Calcined kaolin Powder has some amazing properties that make it highly sought after in many industries.
Calcined kaolin's high brightness and whiteness make it an excellent substitute for titanium dioxide in paint and coatings.
Calcined kaolin also has excellent thermal and electrical insulation properties, which make it ideal for use in ceramics and refractories.
Calcined kaolin Powder is a complex product that involves many steps throughout the production process.
However, the end result is a unique substance that has a wide range of applications and benefits.
Calcined kaolin Powder, also known as Metakaolin, is a processed form of kaolin clay that has been heated at high temperatures (typically between 600 and 800 degrees Celsius) to remove water and other volatile compounds.
This calcination process alters the physical and chemical properties of kaolin, making it suitable for various applications in the construction industry.
Calcined kaolin can be used as a supplementary cementitious material (SCM) in the production of cement and concrete.
When added to cement or concrete mixtures, Calcined kaolin enhances the strength, durability, and workability of the material.
Calcined kaolin acts as a pozzolan, reacting with calcium hydroxide produced during the hydration process of cement to form additional cementitious compounds, resulting in improved performance and reduced environmental impact.
Calcined kaolin is often used in the formulation of mortars and grouts to improve their workability, reduce shrinkage, and enhance adhesion.
Calcined kaolin acts as a filler, providing a smoother consistency to the mixture and reducing the amount of water required for proper hydration.
Geopolymer concrete is an alternative to traditional cement-based concrete that uses a binder composed of aluminosilicate materials.
Calcined kaolin, with its high aluminum content, can serve as a valuable precursor for geopolymer binders, helping to create strong and environmentally friendly construction materials.
Calcined kaolin powder is widely used in the production of paint, coatings, and sealants for construction applications.
Calcined kaolin acts as an extender pigment, enhancing the opacity, brightness, and durability of the coatings.
Calcined kaolin also contributes to improved rheology and reduced cracking.
Fiber cement boards, tiles, and panels are widely used in the construction industry due to their durability and fire resistance.
Calcined kaolin is added to the formulation of fiber cement products as a filler, providing improved strength, dimensional stability, and resistance to weathering.
Calcined kaolin is utilized in the manufacturing of ceramic and porcelain tiles to enhance their strength, whiteness, and firing characteristics.
Calcined kaolin improves the workability of the clay mixture, reduces shrinkage during firing, and helps achieve a smooth and glossy finish.
Calcined kaolin can be incorporated into insulating materials, such as thermal insulation boards, refractories, and firebricks, due to Calcined kaolin's high melting point, low thermal conductivity, and good resistance to high temperatures.
Calcined kaolin powder can be used in road construction as an additive to bituminous materials, such as asphalt, to enhance their stability, durability, and resistance to rutting and cracking.
Calcined kaolin is extensively used in the ceramics industry as a component in the production of ceramic bodies and glazes.
Calcined kaolin improves the strength, whiteness, and thermal stability of ceramic materials.
Additionally, Calcined kaolin is employed in the manufacturing of refractory bricks and castables due to its high melting point and resistance to heat.
Calcined kaolin is utilized as a filler and coating pigment in the paper and packaging industry.
Calcined kaolin enhances the smoothness, brightness, opacity, and printability of paper products.
Calcined kaolin also improves the ink absorption properties and reduces ink bleed, resulting in sharper printed images.
Calcined kaolin acts as an extender pigment in the formulation of paints and coatings.
Calcined kaolin enhances opacity, provides excellent hiding power, and contributes to improved durability and weather resistance.
Calcined kaolin is widely used in architectural coatings, industrial paints, and automotive coatings.
Calcined kaolin is used as a reinforcing filler in plastic and rubber applications.
Calcined kaolin improves mechanical properties, such as tensile strength, modulus, and impact resistance.
Calcined kaolin also enhances dimensional stability, reduces shrinkage, and improves the surface finish of plastic and rubber products.
Calcined kaolin is employed in various personal care products, including cosmetics, skincare formulations, and hair care products.
Calcined kaolin serves as an absorbent, bulking agent, and opacifying agent.
Calcined kaolin helps control oiliness, provides a silky texture, and imparts a matte finish in cosmetic products.
Calcined kaolin is used in pharmaceutical formulations as an excipient and filler.
Calcined kaolin aids in tablet formation by improving flow properties and compressibility.
Calcined kaolin can also be used in topical ointments and creams for its absorption properties and rheological benefits.
Calcined kaolin is utilized in the production of polishes and polishing compounds.
Calcined kaolin provides a fine abrasive action, which helps in achieving a smooth and glossy finish on various surfaces, including metals, plastics, and glass.
Calcined kaolin can be used as a support material for catalysts in chemical processes.
Calcined kaolin offers a high surface area, pore volume, and thermal stability, making it suitable for catalytic applications.
Calcined kaolin is an anhydrous aluminium silicate produced by heating natural china clay to high temperatures in a kiln.
This calcination process gives an increase in hardness and alters the particle shape of the kaolin.
When calcination occurs at around 700°C, the dehydroxylation of the kaolin is complete, forming a partially crystalline metakaolin.
Fully calcined products with an amorphous defect spinel structure are formed above 980°C.
Fully Calcined kaolin can be treated with silane to give a particle surface capable of chemically coupling with the polymer.
Calcined kaolin is derived from the mineral Kaolinite which comes from the Earth’s crust.
Calcined kaolin is an aluminum silicate represented as Al2O3•2SiO2•2H2O.
Calcined kaolins can be used in a wide variety of applications like architectural and industrial coatings, construction, rubbers, plastics, packaging and papers.
Calcined kaolin is employed as a reinforcing agent in rubber compounds.
Calcined kaolin enhances tensile strength, tear resistance, and abrasion resistance in rubber products.
Calcined kaolin can be used as a carrier or diluent in the production of fertilizers.
Calcined kaolin is inert nature and particle size make it suitable for blending with other fertilizer components.
In water treatment applications, Calcined kaolin is used to remove impurities and contaminants.
Calcined kaolin is adsorption properties help in the clarification and purification of water.
Calcined kaolin is sometimes incorporated into cement and concrete formulations to improve workability and reduce water demand.
Calcined kaolin can also contribute to the overall durability and performance of concrete.
The high surface area and porous structure of Calcined kaolin make it suitable as a catalyst support in various chemical processes.
In animal nutrition, Calcined kaolin may be used as an additive to improve digestibility and provide essential minerals.
Calcined kaolin can find applications in the oil and gas industry, such as in drilling fluids and cementing operations, where Calcined kaolin's properties contribute to fluid control and wellbore stability.
Due to its light-scattering properties, Calcined kaolin is used in the production of photocopier and printer toners.
Calcined kaolin is employed in the production of glass fiber reinforcements, where its addition enhances the strength and performance of glass fiber composites.
Calcined kaolin serves as a raw material or processing aid in various chemical manufacturing processes.
Calcined kaolin is a non-metallic mineral, a clay and clay rock dominated by kaolinite clay minerals.
Because Calcined kaolin is white and delicate, it is also called dolomite.
Calcined kaolin is pure kaolin is white, fine and soft, with good physical and chemical properties such as plasticity and fire resistance.
Calcined kaolin is mineral composition is mainly composed of kaolinite, halloysite, hydromica, illite, montmorillonite and quartz, feldspar and other minerals.
Calcined kaolin for Ultramarine is a dehydroxylated aluminum silicate produced at a controlled temperature heating of a water-fractionated kaolin.
Calcined kaolin was specifically designed for Ultramarine products.
Calcined kaolin can greatly improve the acid resistance of Ultramarine products due to its high purity, and Calcined kaolin can also help improve the coloring power due to better metakaolin activity.
Calcined kaolin has better sintering properties, because its raw material is raw ore of coal kaolin blending with natural kaolin ore.
Calcined kaolin is produced by calcining (firing, sintering) kaolin clay or kaolinite rock (flint clay).
Calcination is mainly carried out in rotary kilns, but also in shaft kilns, ring kilns and tunnel kilns.
There are chamottes with different alumina contents and correspondingly different refractoriness.
Depending on the chemical composition, different levels of corrosion and acid resistance are achieved.
Fireclay can be supplied as a raw material in a fineness of 0 to 25 mm or 0 to 50 mm, but also in finished refractory grain sizes and finenesses.
Calcined kaolin is chemically knowns as hydrated Aluminum silicate used any many industries such as Ceramic (Glaze, Engobe, Body grade), Paper, Plastic, Rubber, Pharmaceuticals, Porcelain, Cosmetic, Ink, Dyes, Fiberglass, and Paint Industry.
Calcined kaolin is derived from clay mineral mainly from China clay however Sandy clay and potash clay is also used for kaolin manufacturing.
Calcined kaolin is a layered silicate mineral and is found in many parts of the world, especially in India.
Calcined kaolin is widely used in the ceramics industry as a raw material in the production of porcelain and fine china.
Calcined kaolin is high firing temperature and improved properties make it a valuable component in ceramic formulations.
The enhanced whiteness and opacity of Calcined kaolin make it a popular extender in paint and coating formulations.
Calcined kaolin contributes to the reduction of titanium dioxide (TiO2) content while maintaining or improving performance characteristics.
In the paper industry, Calcined kaolin is used as a coating material to improve printability, opacity, and ink receptivity.
Calcined kaolin helps control ink holdout and enhances the paper's surface properties.
Calcined kaolin is utilized as a functional filler in the production of plastics and rubber goods.
Calcined kaolin improves mechanical properties, reduces shrinkage, and enhances dimensional stability in molded products.
Calcined kaolin finds application in refractory materials where its high temperature stability and low impurity content are advantageous.
Due to its fine particle size and rheological properties, Calcined kaolin is used in adhesives and sealants to control viscosity, reinforce formulations, and improve adhesion.
Calcined kaolin is used in fiberglass production to improve the strength and resistance of glass-reinforced plastic composites.
Additionally, Calcined kaolin can be used as a filler in thermal insulation materials.
In the cosmetic and personal care industry, Calcined kaolin may be used in formulations such as face masks, powders, and creams for its absorbent and texturizing properties.
Calcined kaolin is used in the formulation of adhesives and sealants to improve rheological properties, stability, and performance.
In the cosmetics industry, Calcined kaolin is used in the formulation of various skincare and cosmetic products, including foundations, powders, and masks, due to its absorbent and texturizing properties.
Calcined kaolin may find applications in the pharmaceutical industry for its use as an excipient, contributing to the flow properties and compressibility of pharmaceutical powders.
Calcined kaolin is utilized in plastics and polymers to improve properties such as impact resistance, tensile strength, and dimensional stability.
In the ceramics industry, Calcined kaolin is a crucial component in the production of porcelain and other ceramics.
Calcined kaolin contributes to the fired color, strength, and other properties.
Calcined kaolin is used as a filler in the paper and pulp industry to improve paper properties like opacity, brightness, and printability.
Calcined kaolin is a common extender pigment in paints and coatings, contributing to improved hiding power, rheology, and durability.
In the textile industry, Calcined kaolin is used as a processing aid to improve the smoothness and texture of fabrics during manufacturing.
Calcined kaolin can be used in electronic components and materials due to its insulating properties and compatibility with various manufacturing processes.
In the production of abrasive materials, Calcined kaolin can be added to enhance the abrasion resistance and hardness of the final product.
Calcined kaolin is used in the manufacturing of rubber belts and hoses to improve strength, flexibility, and resistance to wear and aging.
Calcined kaolin is utilized in anti-corrosion coatings to enhance barrier properties and improve the coating's resistance to chemicals.
Markets For Calcined Kaolin:
When formulated into film compounds Calcined kaolin improves the thermal properties of agricultural films, giving the potential to reduce heating costs, reduce the planting to cropping time and increase the length of the growing season.
In film that requires antiblock additive, Calcined kaolin offers an ideal and cost effective balance of antiblock, haze and clarity performance.
In plastics the use of Calcined kaolin is in PVC cable to improve electrical performance and in it’s coated as a functional filler in engineering thermoplastics.
Uses of Calcined Kaolin:
Calcined kaolin-based pigments for paper coatings,extenders and fillers, are ideally suited for replacing Titanium Dioxide or other less cost-effective extender pigments while maintaining brightness,opacity and print-through resistance.
Calcined kaolin is useful in tuning the shrinkage and plasticity of slips applied to wet, leather hard or dry ware.
Because of its low shrinkage from firing out the water crystal, Calcined kaolin is used in castable refractories/molds, and low expansion clay bodies.
Calcined kaolin is one of the oldest and most widely used refractory products.
Calcined kaolin is used as moulding sand in foundries and for acid-resistant bricks.
Calcined kaolin can also be used in the manufacture of paints or paper.
Calcined kaolin is used as a functional extender in paint.
Calcined kaolin has proven to be an excellent extender for titanium dioxide (white) pigment in paint.
Because Kaolin is chemically inert, has high covering power, gives desirable flow properties and reduces the amount of expensive pigments required.
Calcined kaolins are also useful in tuning the shrinkage and plasticity of slips (engobes) which are applied to wet or leather-hard ware.
Engobes contain higher clay percentages than glazes and Calcined kaolin is more important to control their drying shrinkage.
Thus, like for glazes, they can be substituted for part of the raw kaolin to tune drying while maintaining fired properties.
Calcined kaolin can be used in ceramics.
Calcined kaolin’s major property is that it is refractory.
Calcined kaolin softens at about cone 35 and it thus useful in refractory castables and furniture, thermal insulation bodies, low expansion bodies, permeable ceramic compositions, and investment casting.
Calcined kaolin is also very useful in tuning the shrinkage and plasticity of slips (engobes) which are applied to wet, leather hard or dry ware.
Engobes contain higher clay percentages than glazes and Calcined kaolin is more important to control their drying shrinkage.
As with glazes, they can be substituted for part of the regular kaolin to tune drying while maintaining fired properties.
Calcined kaolin is essentially a white mineral used quite often in the creation of porcelain and certain types of ceramics.
In paper industry: Calcined kaolin are widely used paper coatings and fillers.
In rubber industry: Calcined kaolin is mainly use as a Reinforcing agent and filler used, rubber product can be improved Solvent resistance and abrasion resistance.
Calcined kaolin is used in Paint, Plastic, Rubber, Polymer, Paper, Adhesive, and Ceramic industries.
Calcined kaolin is mainly used in the fields such as paint, paper, rubber, engineering plastic, cable, ink to replace TiO2 and cut cost.
While kaolin clay is widely used in its “raw” form, heat treating kaolin to produce metakaolin and other forms of Calcined kaolin further increases its usability and creates an engineered product.
Calcination can enhance or alter a variety of the mineral’s properties to produce a material with characteristics suited to a given application.
This might include improving the hydrophobicity and abrasiveness of the material, or even enhancing optical or electrical characteristics.
The heat treatment process makes Calcined kaolins X-ray amorphous, but they substantially retain their kaolin shape and are used extensively in the pharmaceutical, power cable insulation, extruded profile and film industries.
Interfacial fusion during calcination decreases the aspect ratio and gives them an inert surface.
They also give excellent electrical insulation performance and low dielectric loss due to the lack of crystallinity .
Calcine Kaolin is used pharmaceutical rubber, profile extrusion, thermoplastic vulcanisates (TPV's), rubber cable, high quality rubber flooring, hose, polyurethane sealants, thermal barrier film, antiblock film, seals & gaskets, plasticised PVC cable.
Calcined kaolin used as a functional extender in paint formulations, for cost performance, improves opacity and find application in partial replacement of titanium dioxide.
Calcined kaolin is a type of clay that is made by heating natural kaolin at high temperatures.
Calcined kaolina versatile mineral that has a wide range of applications in various industries.
One of the main advantages of Calcined kaolin is its unique properties, such as its excellent whiteness, chemical stability, low abrasiveness, which make it suitable for use in a variety of applications.
Some common uses of Calcined kaolin include in the paper industry, where it’s used as a coating material to enhance the quality of paper.
Calcined kaolin is also used in the ceramics industry, where it’s added to clay to improve its strength and shrinkage.
The paint and coating industry also uses Calcined kaolin as a functional filler to improve the properties of paint and coatings.
In the plastics industry, Calcined kaolin is added to plastics to improve their mechanical and thermal properties.
The rubber industry uses Calcined kaolin as a reinforcing filler to improve the strength of rubber products.
Calcined kaolin is also used as an additive to enhance the properties of concrete, mortar, and other construction materials in the construction industry.
Consequently, Calcined kaolin has a wide range of applications in various industries, which make it an extremely versatile and valuable material.
The unique properties of this mineral make Calcined kaolin an ideal filler, coating material, and additive in a diverse range of products.
Calcined kaolin is used or glaze recipes that contain excessive, high-shrinkage ingredients like clay, bentonite, Gerstley borate, or magnesium carbonate, a portion of the recipe's kaolin can be replaced by calcined (pre-fired) kaolin to prevent applied glaze cracking and consequent crawling in the fired glaze.
Calcined kaolin pigment can be applied in latex paint, powder coating and electrophoresis coating, filing, paper making industry, ceramic, rubber, and plastic.
Calcined kaolin is one of the most important functional pigment extender based on natural industrial mineral .
Calcined kaolin is washed and scrubbed form of anhydrous kaolin, which is processed under high temperature and pressurized calcination reactors.
Particle shape and size, whiteness, hardness and electrical properties can be adjusted during calcination process.
Paint,paper,plastics and rubber segments are main industries in which Calcined kaolin is used as a pigment extender to save titanium dioxide.
Very low humidity parameters, ultra fine particle distribution, high volume resistivity functions, easy dispersion properties, flame retardant properties, let polymer processors to save so many cost utensils, like carbon black
Some common uses of Calcined kaolin include in the paper industry, where it’s used as a coating material to enhance the quality of paper.
In plastics and cable industry uses:
Plastics can effectively improve the strength and modulus of resistance.
Without reducing the ductility and impact strength.
Calcined kaolin can also improve the performance of products.
In polyvinyl chloride (PVC) cable insulation outer:
PVC plastic product can exponentially increase the volume resistivityAnd inexpensive,
In the PVC flooring, Calcined kaolin can improve performance and surface gloss
In nylon:
Calcined kaolin is used to improve its deflection and tensile strength,
Calcined kaolin is in film and tape used as an Anti-clogging agent, In plastic sheeting to use as adsorbent, etc.
Synthetic zeolite:
New uses of china clay are in the manufacture of synthetic zeolites.
Calcined clay is used as a source of alumina and silica to produce synthetic zeolites.
Synthetic zeolites are used in the refineries and petrochemical industries as molecular sieves.
This use is becoming widely used.
Paint Extender:
Calcined kaolin is used as a functional extender in paint.
Calcined kaolin has proven to be an excellent extender for titanium dioxide (white) pigment in paint.
This is because Calcined kaolin is chemically inert, has high covering power, gives desirable flow properties and reduces the amount of expensive pigments required.
Calcined kaolin's hardness also improves physical durability of the paint film and its burnish resistance.
Paints production:
Better opacity and whiteness make Calcined kaolin a great extender for titanium dioxide.
The hard Calcined kaolin particles help to improve the structural strength of a coating, and also the scrub-resistance of both water and oil-based paints.
They also add corrosion-resistance and fire-resistant properties to the paint.
The disadvantage is the cost.
Calcination and the subsequent milling of the hard calcined particles both require a lot of energy.
This makes Calcined kaolin around three times more expensive than hydrous kaolin.
However Calcined kaolin is still less than half the price of titanium dioxide.
So Calcined kaolin is still a good option as an extender, particularly in paints above CPVC (critical pigment volume concentration).
Ceramics industry:
Good whiteness of Calcined kaolin is useful in ceramics too.
However the most useful property to the ceramist is the fact that Calcined kaolin is already calcined.
Hence Calcined kaolin will have no plasticity and there will be no expansion or contraction of this material.
Calcined kaolin imparts mechanical strength plus and a fine white surface texture.
Calcined kaolin is easy to tell from hydrous kaolin by looking at their data sheets.
Just look at the LOI (Loss on Ignition) value.
For water-washed kaolin it is around 13%, but for Calcined kaolin it will be zero.
The LOI test basically calcines the kaolin.
Hence the LOI is the percentage mass lost due to the loss of the waters of crystallisation.
Rubber and plastics industry:
Calcined kaolin is widely used as a filler in rubber and plastics.
Calcined kaolin will helps impart tensile strength.
Therefore, Calcined kaolin is a reinforcing filler instead of being non-reinforcing like hydrous kaolin.
The fire-resistant property of Calcined kaolin plus the fact that it is an electrical insulator is especially useful in the plastic covering of electric cables.
Calcined kaolin also imparts uv-resistance which is why it is often added to greenhouse film and garden furniture.
Pesticides:
Calcined kaolin has an unexpected usage, as a pesticide.
When sprayed onto fruit, the fine sharp Calcined kaolin particles deter pests by getting into their joints and irritating them.
At the same time Calcined kaolin reflects the sun and acts as a sunscreen.
Calcined kaolin has may other important applications like its usage in paper coating and in petrochemical catalysts.
Calcined kaolin is an interesting product.
Calcined kaolin have been universally used in water base paints because of their excellent balance of properties and cost performance.
Calcined kaolin is also finds in various industries like paints, paper, rubber, printing ink, detergent and ceramic industries.
Calcined kaolin is in a high demand in the global market.
Paper Industry uses:
The primary use of Calcined kaolin is in the paper industry.
Calcined kaolin serves as a paper coating which improves appearance by contributing to brightness, smoothness and gloss.
Calcined kaolin also improves printability.
Additionally, Calcined kaolin is used by the paper industry as a filler reducing cost and the use of tree-based resources.
China, Porcelain and Tableware uses:
Many people are under the mistaken impression that the only use for kaolin is in the manufacture of china.
This is not true, and Calcined kaolin's use by the paper industry far exceeds its other uses.
However, Calcined kaolin still serves as a valuable component in china and other tablewares.
Calcined kaolin's color, gloss and hardness are ideal characteristics for such products.
Uses in Construction:
Cement and Concrete:
Calcined kaolin can be used as a supplementary cementitious material (SCM) in the production of cement and concrete.
When added to cement or concrete mixtures, Calcined kaolin enhances the strength, durability, and workability of the material.
Calcined kaolin acts as a pozzolan, reacting with calcium hydroxide produced during the hydration process of cement to form additional cementitious compounds, resulting in improved performance and reduced environmental impact.
Mortars and Grouts:
Calcined kaolin is often used in the formulation of mortars and grouts to improve their workability, reduce shrinkage, and enhance adhesion.
Calcined kaolin acts as a filler, providing a smoother consistency to the mixture and reducing the amount of water required for proper hydration.
Geopolymer Concrete:
Geopolymer concrete is an alternative to traditional cement-based concrete that uses a binder composed of aluminosilicate materials.
Calcined kaolin, with its high aluminum content, can serve as a valuable precursor for geopolymer binders, helping to create strong and environmentally friendly construction materials.
Surface Coatings:
Calcined kaolin is widely used in the production of paint, coatings, and sealants for construction applications.
Calcined kaolin acts as an extender pigment, enhancing the opacity, brightness, and durability of the coatings.
Calcined kaolin also contributes to improved rheology and reduced cracking.
Fiber Cement Products:
Fiber cement boards, tiles, and panels are widely used in the construction industry due to their durability and fire resistance.
Calcined kaolin is added to the formulation of fiber cement products as a filler, providing improved strength, dimensional stability, and resistance to weathering.
Ceramic and Porcelain Tiles:
Calcined kaolin is utilized in the manufacturing of ceramic and porcelain tiles to enhance their strength, whiteness, and firing characteristics.
Calcined kaolin improves the workability of the clay mixture, reduces shrinkage during firing, and helps achieve a smooth and glossy finish.
Insulating Materials:
Calcined kaolin can be incorporated into insulating materials, such as thermal insulation boards, refractories, and firebricks, due to its high melting point, low thermal conductivity, and good resistance to high temperatures.
Road Construction:
Calcined kaolin can be used in road construction as an additive to bituminous materials, such as asphalt, to enhance their stability, durability, and resistance to rutting and cracking.
Features of Calcined Kaolin:
In Coating:
Calcined kaolin improves structural strength in both water- and oil-based paints.
Calcined kaolin offers good dispersion, chemical stability, corrosion resistance, fire resistance, scrubbing resistance, and mechanical characteristics.
Calcined kaolin can further improve the storage stability, brushability, moisture assistance, and impact resistance of paints and coatings.
Calcined kaolin resists floating and blooming in pigments, improves covering power, durability, and heat and weather resistance, and offers good opacity and adsorption.
Calcined kaolin can partially replace titanium white.
The use of Calcined kaolin in inner and outer wall coatings, high-end paints, inks, and marker line paint can directly cut costs.
In rubber products:
Calcined kaolin is used as a filler in the rubber industry, and can improve products' physical and chemical properties.
Calcined kaolin has a significant reinforcing action, is an electrical insulator, and can improve tear resistance, tensile strength, aging resistance, and corrosion resistance.
Calcined kaolin can enhance solubility in latex, increase vulcanization hardness and abrasion resistance, and boost flex life and smoothness.
Calcined kaolin can cut costs when used as a replacement for such costly materials as abrasion-resistant carbon black, ordinary carbon black, white carbon black, aluminum silicate carbon black, and magnesium oxide.
In ceramics:
Use of Calcined kaolin ensures that products will have a white, fine-textured, glossy surface.
Calcined kaolin can boost mechanical strength and reduce defect rate.
Calcined kaolin is suitable for use as a blank material and glaze in everyday ceramics, construction ceramics, corrosion-resistant chemical engineering ceramics, crafts and art ceramics, sanitary ceramics, and high and low piezoelectric ceramics.
In glass products:
Calcined kaolin replace costly alumina.
When used as a filler in white glass products, Calcined kaolin can improve product quality and reduce production costs.
In plastics:
Calcined kaolin can enhance the strength of greenhouse film, ground film, cable insulation, and PVC pipe (sheet).
Apart from whiteness and electrical insulating properties, Calcined kaolin also allows diffuse light transmission and blocks infrared when used in plastic film.
Calcined kaolin can reduce cost when used as a bulk filler.
In papermaking:
The laminar structure of Calcined kaolin makes it a useful coating pigment in papermaking.
Apart from good covering ability and relatively high luster, Calcined kaolin's porous structure can increase the porosity, soft bulk, and smoothness of coating layers.
Calcined kaolin lends opacity and flexibility to paper, improves ink adsorption, enhances luster, and reduces printing spots.
In fire-resistant materials:
Calcined kaolin is used for linings in metallurgy and chemical engineering.
Calcined kaolin is used include kiln linings, high-temperature fusion crucibles, and various types of bricks, tiles, rods, plates, and non-standard-shape fire-resistant and heat-resistant materials.
In pesticides and petrochemicals:
Calcined kaolin particles are covered with tiny pores that give this material tremendous adsorptivity.
Calcined kaolin can be used in pharmaceuticals and pesticides.
Because Calcined kaolin is neutral and has a high silicon content, it can be used in silicon fertilizer, and can also be used as an animal feed additive.
Calcined kaolin is used as a catalyst in petroleum refining.
Calcined kaolin possesses relatively high basal activity, strongly resists contamination by heavy metals, and offers good catalytic activity and selectivity.
In materials and modern technology:
The modern materials industry uses Calcined kaolin in the production of composite materials.
Calcined kaolin is compatible with both metallic and nonmetallic materials, while offering performance superior to that of metallic and nonmetallic materials in some respects.
Calcined kaolin provides good mechanical strength, impact resistance, radiation resistance, heat resistance, and corrosion resistance.
Because of these properties, Calcined kaolin can be used for high-temperature combustion chambers, nozzles, and cylinders in autos, aircraft, and rockets, etc., and is used in other special and high-strength ceramics.
In cosmetics:
Calcined kaolin is used as a white body pigment employed in facial masks, facial powder, toothpaste, and other everyday products.
Calcined kaolin can cut costs when used instead of titanium white.
Benefits of Calcined Kaolin:
Calcined kaolin Powder is a mineral substance that is derived from kaolin, a type of clay that is found in many parts of the world.
This amazing powder has many benefits that make Calcined kaolin a great addition to various industries such as construction, paper, ceramics.
One of the most significant advantages of Calcined kaolin is its ability to improve the physical properties of materials by enhancing their strength, stiffness, and durability.
Calcined kaolin is known for its ability to increase brightness in products.
Calcined kaolin is versatile and can be used in many different applications, and often used as a substitute for other minerals or pigments because of its unique properties.
Calcined kaolin is also easy to mix with other materials, making it a great additive for creating new products.
Calcined kaolin’s eco-friendly, and its production process has a low impact on the environment.
Calcined kaolin is a cost-effective solution for businesses looking to improve the quality of their products while reducing production costs.
Calcined kaolin can be used in a variety of industries such as paint, rubber, plastic, and many others to improve product performance and quality.
With its unique properties and benefits, Calcined kaolin is an excellent choice for businesses that are looking for a reliable, cost-effective additive to enhance their products.
Characteristics of Calcined Kaolin:
Calcined kaolin has high refractoriness, high volume density, fully calcined.
Aluminum content high, the iron content low; dust content low.
Thermal expansion coefficients of small.
Physicochemical stability.
The specification standards.
Experimental Properties of Calcined Kaolin:
Calcined kaolin is an anhydrous aluminium silicate produced by heating ultrafine natural kaolin to high temperatures in a kiln.
The calcined-kaolin calcination process increases whiteness and hardness, improves electrical properties, and alters the size and shape of the kaolin particles.
Calcined kaolin based pigments for paper coatings,extenders and fillers, are ideally suited for replacing Titanium Dioxide or other less cost-effective extender pigments while maintaining brightness,opacity and print-through resistance.
Formation of Calcined Kaolin:
During the removal of kaolin from nature, there are undesirable impurities in it.
These impurities and some of the water contained in the kaolin are removed from the kaolin by Calcination process.
Calcined kaolin is a form in which kaolin is subjected to calcination process at approximately 1100°C to provide superior optical and physical properties.
Calcined kaolin is used in paint, plastic, rubber, polymer, paper, adhesive and ceramic industries.
Manufacturing of Calcined Kaolin:
Calcined kaolin is a type of clay that is heated to high temperatures, causing it to become more concentrated and purer.
The production process involves several steps, from mining the raw material to grinding and packaging the final product.
First, Calcined kaolin is extracted from the earth and transported to a processing plant.
Once there, Calcined kaolin is crushed and ground into a fine powder using specialized equipment.
This powder is then heated in a furnace to temperatures of up to 1000°C, causing Calcined kaolin to transform into Calcined kaolin.
The heat removes any impurities and increases the clay’s whiteness and brightness.
Calcined kaolin Powder has some amazing properties that make it highly sought after in many industries.
Calcined kaolin's high brightness and whiteness make it an excellent substitute for titanium dioxide in paint and coatings.
Calcined kaolin also has excellent thermal and electrical insulation properties, which make it ideal for use in ceramics and refractories.
Calcined kaolin is a complex product that involves many steps throughout the production process.
However, the end result is a unique substance that has a wide range of applications and benefits.
Whether you are in the paint, ceramics, or refractories industry, Calcined kaolin can help you create high-quality products that stand out from the competition.
Reactions and Synthesis of Calcined Kaolin:
Calcined kaolin is a form of kaolin clay that has been heated to high temperatures (typically between 600°C and 900°C) to remove chemically-bound water and alter its structure.
This thermal treatment transforms the kaolinite structure into a more amorphous material, enhancing its physical and chemical properties.
Calcination Process:
Reaction:
The primary reaction during the calcination of kaolin is the dehydroxylation of kaolinite, which can be represented by:
Al2Si2O5(OH)4→Al2Si2O7+2H2O
Here, kaolinite (Al2Si2O5(OH)4 is converted into metakaolin (Al2Si2O7) and water vapor is released.
Use in Geopolymer Synthesis:
Calcined kaolin (metakaolin) is often used in geopolymer synthesis.
In an alkaline medium, the metakaolin reacts with a sodium or potassium hydroxide solution to form a geopolymer.
This involves dissolution, polycondensation, and hardening reactions, leading to the formation of a three-dimensional aluminosilicate network.
Reaction:
Al2Si2O7+2NaOH→Na2SiO3+Al2O3+H2O
Use in Ceramics:
Calcined kaolin can react with other ceramic ingredients during the firing process to form mullite, which is an essential phase in many ceramic products due to its high thermal stability and mechanical strength.
Reaction:
3Al2Si2O7→3Al2O3⋅2SiO2+SiO2
Here, metakaolin transforms into mullite and free silica during further high-temperature processing.
Reactivity with Lime:
Calcined kaolin can react with lime (Ca(OH)2) in the presence of water to form calcium silicate hydrates (C-S-H) and alumina silicate hydrates (A-S-H), which are important binding phases in materials like concrete and mortar.
Reaction:
Al2Si2O7+Ca(OH)2→C-S-H+A-S-H
Handling and Storage of Calcined Kaolin:
Handling:
Avoid Dust Formation:
Calcined kaolin is a fine powder and can generate dust.
Avoid inhaling dust by using appropriate ventilation or extraction systems.
Minimize Contact:
Use personal protective equipment (PPE) such as gloves, goggles, and dust masks to minimize skin and eye contact.
Safe Transfer:
Handle with care during transfer to prevent spillage.
Use tools that minimize dust generation.
Cleanliness:
Wash hands and any exposed skin thoroughly after handling.
Storage:
Dry, Cool, and Well-Ventilated Area:
Store Calcined kaolin in a dry, cool, and well-ventilated place to prevent moisture absorption, which can affect its properties.
Sealed Containers:
Keep the material in tightly sealed containers to avoid contamination and moisture ingress.
Labeling:
Ensure that containers are properly labeled with the product name and relevant hazard information.
Stability and Reactivity of Calcined Kaolin:
Stability:
Calcined kaolin is stable under normal conditions of use and storage.
Calcined kaolin does not decompose or degrade easily.
Reactivity:
Incompatible Materials:
Calcined kaolin can react with strong acids, which can lead to the release of silica or other harmful components.
Calcined kaolin is generally inert but can form compounds with alkaline materials under certain conditions.
Thermal Stability:
Calcined kaolin remains stable at high temperatures but should not be exposed to open flames or sources of ignition as Calcined kaolin may decompose under extreme conditions.
Hazardous Decomposition Products:
When exposed to strong acids or alkalis, Calcined kaolin can generate hazardous gases or other by-products.
First Aid Measures of Calcined Kaolin:
Inhalation:
Move to Fresh Air:
If Calcined kaolin dust is inhaled, move the affected person to fresh air immediately.
Seek Medical Attention:
If breathing is difficult, seek medical attention.
Skin Contact:
Wash with Water:
In case of contact with skin, wash the area thoroughly with soap and water.
Remove Contaminated Clothing:
Take off any contaminated clothing and wash Calcined kaolin before reuse.
Eye Contact:
Rinse Eyes:
Flush eyes with water for at least 15 minutes.
Keep eyelids open and move the eyeballs around while rinsing.
Seek Medical Attention:
If irritation persists, seek medical attention.
Ingestion:
Rinse Mouth:
If swallowed, rinse the mouth with water.
Do not induce vomiting.
Seek Medical Attention:
Seek medical advice if symptoms develop.
Firefighting Measures of Calcined Kaolin:
Suitable Extinguishing Media:
Calcined kaolin is non-combustible.
Use appropriate extinguishing media for surrounding fires, such as water spray, foam, dry chemical, or carbon dioxide.
Special Hazards:
No Combustion Risk:
Calcined kaolin does not pose a combustion risk, but the dust can become airborne during a fire, potentially causing respiratory irritation.
Protective Equipment:
Firefighters:
Wear appropriate protective clothing and self-contained breathing apparatus (SCBA) when dealing with fires involving this material.
Accidental Release Measures of Calcined Kaolin:
Personal Precautions:
Avoid Dust Generation:
Avoid creating dust.
Use PPE such as masks, gloves, and goggles to prevent inhalation and contact.
Evacuate Area:
If necessary, evacuate the area and ensure proper ventilation.
Environmental Precautions:
Prevent Dispersion:
Avoid dispersing the material into the environment.
Contain the spill to prevent Calcined kaolin from entering watercourses or drains.
Cleanup Procedures:
Mechanical Cleanup:
Use a vacuum cleaner with a HEPA filter or wet sweeping methods to collect the material.
Avoid dry sweeping to reduce dust.
Waste Disposal:
Dispose of the collected material in accordance with local regulations.
Exposure Controls / Personal Protective Equipment of Calcined Kaolin:
Exposure Limits:
Occupational Exposure Limits:
Follow the relevant exposure limits for respirable dust.
These limits may vary depending on the jurisdiction.
Engineering Controls:
Ventilation:
Use adequate local exhaust ventilation to minimize dust exposure.
Dust Suppression:
Employ dust suppression methods like misting or enclosing processes to reduce airborne particles.
Personal Protective Equipment:
Respiratory Protection:
Use NIOSH-approved dust masks or respirators when dust levels exceed occupational exposure limits.
Eye Protection:
Wear safety goggles or face shields to protect against dust irritation.
Skin Protection:
Wear gloves and protective clothing to prevent skin contact.
Identifiers of Calcined Kaolin:
CAS Number: 1332-58-7
EC Number: 215-286-9
Molecular Formula: Al₂Si₂O₇ (metakaolin)
Molecular Weight: 258.16 g/mol (for metakaolin)
Properties of Calcined Kaolin:
item : Calcined kaolin
whiteness %: ≥95
particle size (-2um%): ≥80
325mesh residue(45um)%: ≤0.003
moisture (%): ≤0.5
oil absorbency (g/100g): 55-65
disperse sediment (um): ≤45
PH: 6.0-8.0
refractive index: 1.62
Density: 2.399g/cm3 at 20℃
form: Powder
EWG's Food Scores: 1
EPA Substance Registry System Kaolin, calcined (92704-41-1)
Appearance: Highly micronized powders
GE Brightness (%): ≥90.0
ISO Brightness (%): ≥88.0
325 Mesh residues (%): ≤0.05
Moisture content (105°C)(%): ≤1.0
pH value (28% suspension): 5.0-7.0
Specify Gravity (g/cm3): 2.5 – 2.7
Medium Particle Size (µm): 0.7
Particle size ≤2 µm (%): 80
Dispersion (Hegman): ≥3.5
Appearance: White to off-white powder
Particle Size: 1-10 µm
Density: Bulk: 0.3-0.5 g/cm³; True: ~2.6 g/cm³
Porosity: High
Brightness: 85-95 (GE scale)
Refractive Index: ~1.62
Composition:
SiO₂: 54-60%
Al₂O₃: 40-45%
Fe₂O₃/TiO₂: Trace (<1%)
LOI: 0-1%
pH: 4.5-6.5
Solubility: Insoluble in water
Thermal Stability: Stable up to 1000°C+
Dehydroxylation: ~600-900°C
Specifications of Calcined Kaolin:
Color: White to off-white
Particle Size: Median 1-10 µm
Bulk Density: 0.3-0.5 g/cm³
Specific Surface Area: 10-20 m²/g (BET method)
Brightness: 85-95 (GE scale)
Moisture Content: ≤ 0.5%
Silica (SiO₂): 54-60%
Alumina (Al₂O₃): 40-45%
Iron Oxide (Fe₂O₃): ≤ 0.8%
Titanium Dioxide (TiO₂): ≤ 1.5%
Loss on Ignition (LOI): 0-1%
pH: 4.5-6.5
Dehydroxylation Temperature: 600-900°C
Thermal Stability: Stable up to 1000°C+
Refractive Index: ~1.62
Oil Absorption: 35-45 g/100g (ASTM D281)