engleski

Mechanochemical synthesis of calcium carbonate polymorphs

Calcium carbonate is a common mineral that appears in a form of several hydrated phases and three polymorphs: calcite, vaterite and aragonite. Because of its stability, availability and biocompatibility, it is one of the most important filler used for paper, plastics, rubber or paints production. CaCO3 can be readily prepared via the solution (liquid + liquid ® solid) or the carbonation (gas + liquid ® solid) route. However, mechanochemical processing has been recently proposed as an alternative method of CaCO3 preparation, which contributes to homogeneous distribution of phases, control of particle size distribution and prevention of agglomeration. The aim of this study is to identify the factors that favor the formation of calcium carbonate polymorphs by mechanochemical treatment of different reactants in ball mill. The obtained samples of calcium carbonate were characterized by FTIR–ATR spectroscopy, PXRD and SEM microscopy and it was found that vaterite, calcite or aragonite could be prepared by selecting the appropriate source of calcium ions. The properties of thus obtained samples were compared with CaCO3, which has been prepared by conventional, solution mediated, synthetic routes.

Calcium carbonate ; mechanochemistry ; polymorphism

nije evidentirano