Thermal Plasma Synthesis of Anorthite.

The paper deals with the thermal plasma synthesis of anorthite (CaO·Al₂O₃·2SiO₂). It is shown that the optimum synthesis parameters include 100 A current, 110 V voltage, 14 nL/min gas rate, and 25–30 s exposure time. According to the X-ray diffraction analysis, the initial mixture melting provides the silicate melt formation followed by its cooling and the anorthite phase formation. For the synthesis of the anorthite phase enriched with the calcium-containing CaO·Al₂O₃·2SiO₂·nCaO compound, it is necessary to increase the calcium oxide content up to 38%. For synthesis of the anorthite phase enriched with silicon-containing CaO·Al₂O₃·2SiO₂·nSiO₂ compound, the silicon oxide content must be increased up to 67%. Idiomorphism of anorthite acicular crystals is observed. The practical implication of synthesized anorthite is the ceramics production. [ABSTRACT FROM AUTHOR]