Metasil

Since the early 1990s, the use of pure metakaolin for construction purposes has been on the rise. Metakaolin is not a novelty in technically advanced industries; it is a material that has been proven over decades, which brings higher parameters to final products and ultimately represents a financial profit. Current metakaolin production is technologically perfect, and the technological process itself is part of the producer’s valuable know-how.

Metasil is a specially prepared metakaolin with defined properties and currently fully replaces the waste product used to date – silica fume (microsilica).

MANUFACTURING TECHNOLOGY

Metasil is ground, calcined, washed kaolinite Al2O3.2SiO2.2H2O. During heat treatment, kaolinite undergoes dehydroxidation, i.e. a loss of up to 14% of hydroxyl water, and depending on the technological process used, a product with varying degrees of activity is produced. Metasil is further technologically modified by grinding, and the resulting product is a tasteless and odorless powder with excellent usable properties.

Al₂O₃ . 2SiO₂ . 2H₂O → Al₂O₃ . 2SiO₂+ 2H₂O

CHEMISM REACTION

The set of reactions between alkalis from cement and Metasil is called the pozzolanic reaction, which produces layered or three-dimensional products of hydration processes. This process modifies the composition and structure of the gel phase, thereby changing the structural and mechanical properties of cement mortars and concretes. Modified versions of Metasil are tailor-made products for price-conscious customers as well as customers requiring a product for highly specialized applications.

METASIL EFFECTS - THE BARE FACTS

INCREASES MECHANICAL PROPERTIES

The addition of Metasil to cement mortars and concretes results in a denser arrangement of hydration products and, compared to the reference sample without Metasil, higher compressive and flexural strengths are achieved. Metasil is now a fully-fledged substitute for silica fume (microsilica) not only in terms of practical use and experimental tests, but also in terms of affordability.

FROST RESISTANCE AND RESISTANCE TO CDA

Simulation tests and long-term observations on completed construction projects have shown that the addition of Metasil significantly increases resistance to cyclic freezing. The higher density of the cement product results in lower water absorption and higher resistance to chemical de-icing agents (CDA) used in road maintenance.

LOWER ABSORPTION

Products containing Metasil exhibit lower water absorption, which is particularly advantageous for end products that come into direct contact with atmospheric influences – plasters, cement mortars, exposed concrete.

TEMPERATURE RESISTANCE AND ACID RESISTANCE

Metasil-modified mixtures are used for their higher temperature resistance in the field of refractory materials. Products with metasil microfillers exhibit higher resistance to acids.

ELIMINATION OF EFFLORESCENCE

The use of Metasil blocks the chemical process that causes calcium efflorescence on finished building products. The resulting product is thus much more aesthetically pleasing.

SUPPRESSES ALKALI-SILICA REACTION

Amorphous silica from sand or aggregate can react with alkalis contained in cement (defined by Na₂O content), causing expansion and total destruction of the cement product. The addition of Metasil to the mixture suppresses this effect. This fact was verified between 1962 and 1979, when 260,000 tons of metakaolin were used in the construction of four dams for Amazonian reservoirs.

DISPERSIBILITY AND CAKING

Compared to microfillers used to date, Metasil exhibits a higher degree of dispersibility. It is more resistant to caking, which results in the absence of inhomogeneities in the dry mixture and reduces the formation of defects in the final product.

METASIL AS A BINDER AND FILLER

Metasil, as a latent hydraulic binder, can be alkali-activated to form geopolymers, materials that exhibit much higher material properties compared to cement products. Metasil can also be used as a filler in the rubber industry, where it successfully replaces precipitated silica. It increases resistance to UV radiation and electrical insulation.

USE OF METASIL

Additive for mortars, plasters, and concrete

Higher compressive and flexural strength, higher frost resistance and weather resistance, lower water absorption.

Total replacement of microsilica and partial replacement of cement

Higher compressive and flexural strength, higher frost resistance and resistance to weathering, higher resistance to CDA, lower water absorption, lower tendency to "bleeding" of the mixture, elimination of calcium efflorescence, suppression of alkali-silica reaction.

Filler in the rubber industry

Substitute for precipitated silica.

Microfiller for refractory materials

Temperature resistance and acid resistance.

Geopolymer binder

Latent hydraulic binder of alkali-activated geopolymers.

TECHNICAL SERVICE FOR CUSTOMERS

Selection of a suitable type of Metasil for testing in your laboratories

Testing your current products

Fine-tuning your recipe using the appropriate amount of Metasil

Material and economic comparison of alternatives

PACKAGING

Standard large-volume bags (500 kg) with PE liner and pallet base; other bag sizes or tank delivery available upon request.

Recommendations for handling and storage

Due to its nature, the material tends to create dust. The packaging must be sealed airtight to prevent water and air humidity from being absorbed into the material. The product must not be contaminated with foreign substances. The product must be stored in covered warehouses where fluctuations in humidity and temperature are limited. The shelf life is 6 months from the date of shipment to the customer, provided that the storage conditions are observed.

Health safety information

Current information and knowledge characterize the dust from the product as dust without hazardous properties within the scope of Act No. 350/2011 Coll. (S sentence: S22 – do not breathe dust). It is not subject to registration and is not a hazardous substance within the meaning of Regulation (EC) No. 1907/2006 (REACH). It does not meet the criteria for classification according to Regulation (EC) No. 1272/2008 (CLP). It is not classified as a hazardous substance or mixture according to Regulation 67/548/EEC.

Additional information

The information provided in the material data sheet is based on the current state of technology and scientific knowledge. For use in products and semi-finished products, the product must be tested by the customer, and the supplier cannot guarantee its suitability for use. The supplier provides technical service for areas of application.

EKONRAD, s.r.o.

Hybešova 724/38
602 00 Brno
ID: 25372220
VAT: CZ25372220

Phone: +420 731 746 060
Phone.: +420 538 707 125
E-mail: info@ekonrad.cz
Official Data Box: sdm3dcf

Bank account details
Account number: 1389342379/0800
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