The use of vaterite as a trap for metallie ions in water. Study of copper/vaterite and manganese/vaterite system

Abstract

The crystalline transformation of vaterite into cubic calcite can be carried out under the influence of various aqueous solutions present in nature (tap water, various mineral water). It can also be performed due to heating under air or inert atmosphere. During its transformation, the vaterite can trap ions present in the aqueous medium. UVVis/NIR and EPR analyses carried out on samples recovered after reaction with different solutions of Cu2+ and Mn2+ show the presence of these ions in the structure of calcite after transformation. That demonstrates the capacity of vaterite to imprison metal ions during its transformation into cubic calcite. Mn2+ EPR signals detected after reaction of vaterite with demineralized water confirms trapping efficiency of vaterite in the presence of low ions contents.