Study of Structural and Thermal Properties of SiO2 and MgO in the Diatomite

Year 2016, Volume: 2 Issue: 2, 20 - 23, 30.12.2016

Khaled Boubendıra Kotbia Labıod Et Al.

Abstract

The
diatomite still called kieselguhr is a rock formed by accumulation in old
lakes, carapaces of diatoms which are fossil algae with siliceous skeleton
amorphous and slightly hydrated. The diatoms are very abundant and there are
several species corresponding to species different of diatomite.     In this work we determine the structural
and thermal properties of SiO₂ and MgO in the diatomite using the
plane wave method and linearized augmented (LAPW) in the functional theory of
density (DFT). The potential for exchange and correlation is calculated by the
generalized gradient approximation (GGA). For the thermal properties, we calculated the free enthalpy G, S
entropy, specific heat C, thermal conductivity λ ..... etc of SiO₂
and MgO component. The temperatures used in this work are 1400, 1450 and 1500
respectively;The results are in good agreement with some experimental data.

Keywords

DFT, Diatomite, Thermal

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