Ethylene Glycol-Water Binary System Control Synthesis of Convex Lens-Like Calcium Carbonate

Without adding macromolecular organic matter as control agent,convex lens-like calcium carbonate particles with uniform size,regular morphology were synthesized via the low-temperature solvothermal method using anhydrous calcium chloride and urea as raw materials and ethylene glycol-water as the solvent. The effects of Ca2+ concentration and aging time on calcium carbonate′s images were studied. In order to research the influence of alcohols solvent system on calcium carbonate′s image,calcium carbonates were also produced by water,alcohol-water solution and glycerol-water solution with same process. At last,the formation mechanism of convex lens-like calcium carbonate was discussed. The results show that the convex lens-like calcium carbonate mainly consisted of vaterite mixed with part of calcite. The molecular structure of the alcohols plays a key role in controlling of the phase structure and image of calcium carbonate. Increasing Ca2+ concentration make the surface of convex lens-like calcium carbonate rough. With the elongation of aging time,the convex lens-like calcium carbonate gradually develop into a hollow structure and finally dissolution-recrystallization.