Equilibrium behavior of magnesian calcite mineral : a theoretical approach

Abstract EN

A theoretical approach is used to explain the equilibrium behaviour of magnesian calcite in aqueous solutions.

This approach is based on the original work of Wollast and Reinhard-Derie, 1977, which is modified herein to consider the effects of the quantities of solid surface area to aqueous solution volume on the chemical equilibrium of magnesian calcite.

According to this theoretical approach, it is favourable that there will be more than one thermodynamic equilibrium phase for magnesian calcite.

This is addressed by using the phase rule equilibrium, which shows that an additional degree of freedom is created by solid solution.

With regards to differences in the results of magnesian calcite ionic activity products obtained by different workers, they could be real thermodynamic equilibria of different states depending upon solid-to-solution ratios.

One thermodynamic equilibrium may be reached, if high solid-to-solution ratio is used at certain (Mg2+ ) : (Ca2+) in the solution.