Industrial & Engineering Chemistry Research, Vol.40, No.11, 2445-2451, 2001
Surface analysis of ground calcium carbonate filler treated with dissolution inhibitor
This work demonstrates that the solubility of ground calcium carbonate (GCC) decreased when GCC was treated with phosphate-containing chemical inhibitors. The extent of inhibition of the dissolution process was found to increase With inhibitor dosage until a saturation point was reached, beyond which further addition of inhibitor did not have any further effect. The mechanism of the inhibition was investigated by conducting surface analysis of the treated G;CC. X-ray photoelectron spectroscopy, X-ray diffraction, transmission electron microscopy, and energy-dispersive X-ray analysis were employed to confirm the presence of phosphate on the surface of the treated GCC. Scanning electron microscopic pictures revealed that the treated GCC particles had a different surface morphological pattern than the untreated GCC particles. It is proposed that the inhibition was brought about by the precipitation of calcium phosphate phases such as hydroxyapatite on the GCC surface.