Effects of sodium laurylsulfate on crystal structure of calcite formed from mixed solutions

Sodium laurylsulfate (SLS), an anionic surfactant, was used for tailoring calcite via a solution route. SLS was dissolved in calcium and carbonate source solutions at various concentrations and critical micelle concentrations (CMCs). The crystallized particles were characterized using X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), laser-scattering particle size measurements, and thermogravimetric analysis (TGA). Energy dispersive spectroscopy (EDS) analysis was carried out to measure sulfur profiles on the surface of the particles. SLS tended to produce small calcite particles in the carbonate source solution, whereas this effect was not obvious in the calcium source solution. It is believed that the electrostatic repulsion force in the carbonate source solution contributes to the different particle refining effects of SLS seen in the two solutions.

SEM-EDS images of sulfur distribution on crystallized calcite surfaces. The abnormally large particles were precipitated by macroreactors, a flocked form of microreactors consisting of micelles..Figure optionsDownload high-quality image (50 K)Download as PowerPoint slideResearch highlights
► Carbonate source solutions containing sodium laurylsulfate (SLS) crystallize calcite.
► CMCs are suitably adjusted to 0.5 M calcium and carbonate source solutions.
► Formation of macroreactors induced by interaction of microreactors with micelles is suggested.