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Spinning up the polymorphs of calcium carbonate.

ABSTRACT: Controlling the growth of the polymorphs of calcium carbonate is important in understanding the changing environmental conditions in the oceans. Aragonite is the main polymorph in the inner shells of marine organisms, and can be readily converted to calcite, which is the most stable polymorph of calcium carbonate. Both of these polymorphs are significantly more stable than vaterite, which is the other naturally occurring polymorph of calcium carbonate, and this is reflected in its limited distribution in nature. We have investigated the effect of high shear forces on the phase behaviour of calcium carbonate using a vortex fluidic device (VFD), with experimental parameters varied to explore calcium carbonate mineralisation. Variation of tilt angle, rotation speed and temperature allow for control over the size, shape and phase of the resulting calcium carbonate.

SUBMITTER: Boulos RA

PROVIDER: S-EPMC3898216 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature

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Spinning up the polymorphs of calcium carbonate.

Boulos Ramiz A RA Zhang Fei F Tjandra Edwin S ES Martin Adam D AD Spagnoli Dino D Raston Colin L CL

Scientific reports 20140122

Controlling the growth of the polymorphs of calcium carbonate is important in understanding the changing environmental conditions in the oceans. Aragonite is the main polymorph in the inner shells of marine organisms, and can be readily converted to calcite, which is the most stable polymorph of calcium carbonate. Both of these polymorphs are significantly more stable than vaterite, which is the other naturally occurring polymorph of calcium carbonate, and this is reflected in its limited distri ...[more]

PMID: 24448077

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