In Situ Observation of the Dissolution of Spherical Alumina Particles in CaO–Al₂O₃–SiO₂ Melts

Abstract

The dissolution of alumina spheres in a synthetic CaO–Al2O3–SiO2 (CAS) slag was investigated in situ with a confocal scanning laser microscope (CSLM) in the temperature range between 1470° and 1630°C. Through image analysis, the evolution of the apparent particle radius is obtained as a function of time, exhibiting a clear temperature dependence. The rate‐limiting step of the dissolution process is first evaluated with respect to the classical shrinking core model. Neither the boundary layer diffusion nor the chemical reaction in this model can fully explain the dissolution phenomena. By comparing the experimental results with numerical simulation, the rate‐limiting step was shown to be diffusion in the majority of the tests. Effective binary diffusion coefficients were calculated.

In situ observation of the dissolution phenomena of SiC particle in CaO–SiO2–MnO slag

“…CSLM work has been carried out on the dissolution phenomena of MgO, Al 2 O 3 and MgAl 2 O 4 microparticles in the CaO-SiO 2 -Al 2 O 3 (-MgO) slags. [12][13][14][15][16] Consequently, in the present study, the dissolution of SiC particle at 1600 • C in the CaO-SiO 2 -MnO slag is observed in situ by means of CSLM and analyzed in order to make the determination of dissolution 0955-2219/$ -see front matter © 2010 Elsevier Ltd. All rights reserved. doi:10.1016/j.jeurceramsoc.2010.07.020 mechanism, which has not been clarified yet, more straightforward.…”

Dissolution Kinetics of SiO2 into CaO-Fe2O3-SiO2 Slag

“…This result was similar to that of previous studies. [5,6,[20][21][22][23][24] Therefore, R d was calculated using Eq. [1]:…”

Dissolution Behavior of Alumina-Based Inclusions in CaF2-Al2O3-CaO-MgO-SiO2 Slag Used for the Electroslag Metallurgy Process

“…In recent years, Monaghan and Chen [16], Fox and Valdez et al [17], Verhaeghe and Liu et al [18], Liu and Verhaeghe et al [19], and Orrling and Sridhar et al [20] employed laser scanning confocal microscopy (CSLM) to investigate the dissolution of inclusions in slag. CSLM enables the in -situ observation of the dissolution of inclusions.…”