Morphological control of calcium carbonate crystallized in reverse micelle system with anionic surfactants SDS and AOT

• Published in: Journal of colloid and interface science Vol. 288; no. 2; pp. 496 - 502
• Main Authors: Kang, Sung Hoon, Hirasawa, Izumi, Kim, Woo-Sik, Choi, Chang Kyun
• Format: Journal Article
• Language: English
• Published: San Diego, CA Elsevier Inc 15.08.2005; Elsevier
• Subjects: Calcite; Calcium carbonate; Chemistry; Colloidal state and disperse state; Emulsions. Microemulsions. Foams; Exact sciences and technology; General and physical chemistry; Micelles. Thin films; Microemulsion; Structural control; Vaterite; Vaterite; Microemulsion; Calcite; Calcium carbonate; Structural control; Anionic surfactant; Reverse micelle; Ionic surfactant; Structural control: Calcite; Lauryl sulfate
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2005.03.015

The influence of a surfactant over water on the polymorphism and crystal size of calcium carbonate produced by reaction crystallization in microemulsion systems was investigated in a mixing tank reactor. The crystallization was induced by the reaction between two aqueous micelle solutions (Na 2CO 3–CaCl 2) stabilized by anionic surfactants, SDS (sodium dodecyl sulfate) or AOT (sodium bis(2-ethylhexyl) sulfosuccinate). With increasing surfactant ratio to water, the water-in-oil microemulsion was stably developed and the morphology of the calcium carbonate crystallized in the micelles sharply transformed from calcite to vaterite. The influence of SDS on the polymorphism and crystal size of calcium carbonate was much clearer than that of AOT. In addition, with AOT, certain step changes in the morphology and crystal size occurred around a surfactant ratio to water ( R = [ H 2 O ] / [ surfactant ] ) of 15 due to a two-phase separation of the microemulsion.