Resumen de Sustituciones SeO42--SO42- en el yeso: un estudio experimental
Ángeles Fernández González, A. Andara, Manuel Prieto Rubio
Selenate (SeO2-4) and sulfate (S02-4) have similar structural and chemical properties, and they can play a similar geochemical role. The competition between both anions has been considered in different fields. We present experimental work on crystallisation of Ca (SeO4 ,S04) 2H2 0 solid solutions from aqueous solutions. A complete structural characterization of salid solutions by X-ray powder diffraction and thermocalorimetic analysis were carried out. The differences in structural parameters for the different salid compositions have allowed us to quantify the non-ideality of the salid solution and the calculation of a thermodynamic model of this salid solution-aqueous solution system. In addition, the work includes some observations on dehydration behaviour of CaSeO4.2H2 0-CaSO4.2H2 0 endmembers and salid solutions.
