Upgraded grade silicon or Chemical grade silicon (CGS) is 99%-99.99% pure silicon with aluminium and iron being the major source of impurities. The main application of CGS is in chemical industry to produce silicon polymers which are a vast group of polymers with about 9000 different products including silicon rubber, silicon based oils and grease, resins, pastes, cosmetics materials, silanes,..CGS is used extensively in the chemical industry.Chemical Grade Silicon Metal is the basic raw material in the production of special silicones also called light oils.

Impurity Concentrations in MG-Si (ppm) Element Concentration Fe 160-650 Al 100-500 Ca 50-200 Ti 15-30

The production of CGS is mainly through hydro-metallurgical purification on metallurgic Silicon. Roughly half of silicon production is used in production of chemicals in the world.

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