Production of Vaterite Type Calcium Carbonate by using Oyster Shell Waste with Lysine

Abstract

The experiments to produce the vaterite type calcium carbonate were conducted for using the waste oyster shell as the recycling resources. Firstly, the oyster shell were calcinated at 800 degrees C for 24 h. Calcinated oyster shell were reacted with the nitric acid solution, and were diluted to 0.1 M Ca(NO3)(2) solution. This solution was mixed with 0.1 M Na2CO3 contained 0.1 mol lysine/1 mol CaO at 20 degrees C and 600 rpm mixing condition for 1 h. The reaction products were identified to vaterite type calcium carbonate (84.5% vaterite, 15.5% calcite) by XRD and SEM analysis. Mean particle diameter was 6.87 mu m, and the lysine content in calcium carbonate was analyzed to 0.1%.