Mikrosilika

Microsilica is a compacted amorphous powder obtained as a by-product in the metallurgical process of silicon and ferrosilicon alloys in an electric arc furnace. Fumes escaping from the furnace oxidize and condense in the form of very fine particles of amorphous silica SiO2. This form of silica is more active than, for example, the crystalline form. The small grain size of microsilica favors denser packing of concrete components.

The offered Microsilica is produced in Iceland using renewable energy. The production plants use only the geothermal resources of the island, thanks to which the final product is not burdened with a carbon footprint. During the production of Microsilica in ecological plants in Iceland, no greenhouse gases are emitted into the atmosphere.

In concrete mixes Microsilica improves the anti-corrosion protection of reinforcement, increases the resistance of the finished concrete product to water penetration and supports the increase in strength through a secondary pozzolanic reaction. It improves the rheology of the concrete mix, enables the production of concrete with high strength classes.

Properties:

Product name: ................................................ Microsilica
Synonyms: ........................................................ microsilica, silica fume, amorphous silica (SiO2), powdered silicon dioxide
IUPAC name: ............................................................. silicon dioxide
CAS No.: ................................................................. 69012-64-2
EINECS No.: ................................................................. 273-761-1
REACH No.: ............................................................. 01-2119486866-17
Form: .................................................................. Ultrafine amorphous powder (respirable dust). The dust forms agglomerates.
Color: .................................................................. gray, light gray.
Odor: ................................................................ odorless.
Melting point (°C): ............................... 1550-1570
Solubility (water): ......................................... insoluble / slightly soluble.
Solubility (organic solvents): ..... insoluble / slightly soluble.
Loss on ignition (1173 K): ................................ 1.5%
Humidity after packaging (378 K): ......................... 0.2%
pH: ............................................................................. 7.2
BET (m2/g): ................................................................. 20 - 27
Specific gravity (water = 1): ................................... 2.2 - 2.3
Bulk density (kg / m3): .................................. ≈ 550-750
Specific surface area (m2 / g): ............................. 15-30
Particle size: ............................................................. average (μm) 0.15 (less than 0.1% of primary particles > 45 μm)

Nominal composition of dry matter:

SiO2 (diff.) …………………………. 95%

Al2O3 ……………………………….. 0.3%

C* ……………………………………. 1.8%

CaO …………………………………….. 0.7%

Fe2O3 ………………………………. 0.1%

K2O …………………………………….. 0.4%

MgO ……………………………………. 0.2%

Na2O …………………………………… 0.1%

* without C in SiC