Preparation of Hollow Calcium Silicate Microparticles by Simple Emulsion

Eiichi Toorisaka^1*, Syotaro Nagamatsu², Yasunobu Saruwatari², Makoto Hirata², Tadashi Hano²

¹Department of Environmental Science and Engineering, Yamaguchi University, Yamaguchi, Japan.
²Department of Applied Chemistry, Oita University, Oita, Japan.

DOI: 10.4236/jeas.2014.44012                

Abstract

Hollow calcium silicate microparticles were prepared by mixing a water-in-oil (W/O) emulsion containing silicate ions in aqueous phase with an oil phase containing a calcium/di-2-ethylhexyl phosphoric acid (D2EHPA) complex. The inorganic precipitation reaction at the oil-water interface was accelerated by using a simple W/O emulsion. Hollow microparticles were obtained when the mole ratio of D2EHPA and calcium in the oil phase was nearly 2:1. The shell formation of the par-ticles depended on the acceleration of the precipitation reaction, which could be accomplished by controlling the concentrations of the calcium and silicate ions.

Keywords

Hollow Inorganic Microparticle, Water-in-Oil Emulsion, Solvent Extraction, Interfacial Reaction

Conflicts of Interest

The authors declare no conflicts of interest.

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