Dissolution kinetic of Algerian dolomite in sulfuric acid


Bouckherit C., Kolli M., Altıner M.

1st MatScience 2022, Khenchela, Algeria, 13 - 15 December 2022, pp.1

  • Publication Type: Conference Paper / Summary Text
  • City: Khenchela
  • Country: Algeria
  • Page Numbers: pp.1
  • Çukurova University Affiliated: Yes

Abstract

In this work, the dissolution kinetic of an Algerian dolomite in aqueous sulfuric acid solution was investigated. Before leached, the used dolomite was firstly characterized (XRF, XRD, and particle size distribution). The study of the reaction kinetic was carried out by following the released CO2 volume until complete reaction was achieved, for three different leaching temperatures: T=35, 50 and 65 °C.

The obtained results showed that used dolomite exhibit a CaO/MgO ratio equal to 1.54 which is quite acceptable compared with other dolomites. The most significant impurities are SiO2 (0.4 %), Al2O3 (0.23 %), and Fe2O3 (0.11 %). XRD result showed that used raw material is mainly composed of dolomite mineral CaMg(CO3)2 associated with a minor quantity of calcite CaCO3. The particle size distribution is in the form of a more or less symmetrical inverted bell. The maximum particle size is dmax = 1160 µm and the mean particle size is d50 = 190 µm.

From dissolution kinetic tests, it was noted that dolomite dissolution increased over time with increasing temperature. A kinetic model was proposed to describe the dissolution of used dolomite ore, by analysis of the experimental data. It was shown that the leaching process was controlled by the diffusion-reaction. The activation energy of the leaching process was found approximately Ea=31.98 kJ mol–1.