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Updated: Jun 6, 2026
09:31
Calcium Carbonate Formation in the Presence of Biopolymeric Additives
Published on: May 14, 2019
Interaction between biopolyelectrolytes and sparingly soluble mineral particles
Peter Versluis1, Alois K Popp, Krassimir P Velikov
1Unilever R&D Vlaardingen, Olivier van Noortlaan 120, 3133 AT Vlaardingen, The Netherlands.
Langmuir : the ACS Journal of Surfaces and Colloids
|December 3, 2010
Summary
Carrageenans stabilize calcium carbonate (CaCO(3)) particles through surface absorption and weak yield stress, preventing settling. Interactions lead to CaCO(3) dissolution and formation of new particle structures.
Area of Science:
- Colloid and Surface Science
- Materials Science
- Biopolymer Chemistry
Background:
- Calcium carbonate (CaCO(3)) is a sparingly soluble mineral salt widely used in industrial applications.
- Carrageenans are negatively charged biopolyelectrolytes with sulfate groups, often used as stabilizing agents.
- Understanding mineral-polyelectrolyte interactions is crucial for controlling dispersion stability and material properties.
Purpose of the Study:
- To investigate the physicochemical interactions between calcium carbonate particles and carrageenans in aqueous dispersions.
- To elucidate the stabilization mechanisms of CaCO(3) particles by carrageenans.
- To explore the formation of new structures resulting from these interactions.
Main Methods:
- Adsorption measurements to quantify carrageenan uptake onto CaCO(3) particles.
- Confocal laser scanning microscopy to visualize particle interactions and precipitate formation.
- Rheological measurements to assess the apparent yield stress of the dispersions.
Main Results:
- Carrageenans adsorb onto CaCO(3) particle surfaces, providing electrosteric stabilization.
- Dispersions exhibit a weak apparent yield stress, enabling particle suspension for extended periods.
- Adsorption data suggest interactions beyond simple monolayer formation, with evidence of polyelectrolyte-precipitate complex formation.
- Carrageenan induces partial dissolution of CaCO(3), with Ca(2+) ions interacting with sulfate groups to form aggregated structures.
Conclusions:
- Carrageenans effectively stabilize calcium carbonate dispersions through a combination of surface adsorption and induced rheological properties.
- The interaction mechanism involves dissolution of CaCO(3) and subsequent aggregation with carrageenan, forming novel particle-like structures.
- These findings offer fundamental insights into mineral-polyelectrolyte systems with significant implications for industrial applications involving calcium carbonate.
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