Synergistic Effect of Additives in CaCO3 Precipitation System at Different Initial pH

Vojtkuf, Iva; Andrašić, Marko; Kralj, Damir; Kontrec, Jasminka; Njegić Džakula, Branka (2024) Synergistic Effect of Additives in CaCO3 Precipitation System at Different Initial pH. Croatica Chemica Acta, 97 (4). pp. 175-187. ISSN 0011-1643

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Official URL: http://doi.org/10.5562/cca4098

Abstract

In this study, the synergistic effect of magnesium ions (Mg2+) and poly-L-aspartic acid (pAsp), at different initial pH (pHi), on the spontaneous precipitation of calcium carbonate (CaCO3), as a model precipitation system for investigating biomineralization in marine organisms, was investigated. The research was conducted in systems with pHi from 8.3 to 10.5, molar ratio n(Mg2+) : n(Ca2+) = 1 : 5 and pAsp concentration from 1–5 ppm. By comparing synergistic systems with the model system as well as with systems where Mg2+ or pAsp were individually added, it was observed that as a consequence of the synergistic effect of Mg2+ and pAsp in the entire investigated pHi range enhanced inhibition of CaCO3 precipitation process occured as well as the change in: polymorphic composition of precipitated CaCO3 and morphology of individual polymorphs. Inhibition of precipitation was intensified with the increase in pHi, and regarding the polymorphic composition of the precipitate pAsp played a crucial role at lower pHi while Mg2+ was decisive at higher pHi. These results clearly indicate the significance of pHi in the synergistic effect of Mg2+ and pAsp.

Item Type:

Article

Uncontrolled Keywords:

calcium carbonate; poly-L-aspartic acid; magnesium; synergy; pH; calcite; vaterite; aragonite; climate change

Subjects:

NATURAL SCIENCES > Chemistry

Divisions:

Division of Materials Chemistry

Projects: