Synthesis and characterization of hydrophobic calcium carbonate particles via a dodecanoic acid inducing process

A carbonation route for the synthesis of hydrophobic calcium carbonate was studied. In the process, dodecanoic acid was used as an organic substrate to induce the nucleation and growth of calcium carbonate. The calcium carbonate particles were produced by means of carbonation of the mixture of calcium hydroxide and dodecanoic acid by bubbling CO2/N2 gas mixture. The operating parameters such as temperature and the concentration of the organic substrate were varied to study their influences on the active ratio and contact angle of calcium carbonate particles. The morphology of the calcium carbonate particles was characterized with scanning electron microscopy (SEM). The synthesized calcium carbonate particles in the presence of the organic substrate are rod-like and ellipse-like particles. The polymorphs were characterized with X-ray diffraction (XRD).

This figure shows the sessile drop profiles, on the calcium carbonate pellets produced from powders obtained in the (a) absence and (b) presence of dodecanoic acid during the in situ preparation process. From the contrast of the pictures we know that via the molecular recognition, the hydrophobic tail outward changed the surface property of calcium carbonate particles, from hydrophilic to hydrophobic.Figure optionsDownload as PowerPoint slide