Abstract:

The influence of sodium dodecyl sulphate, SDS, dodecyl ammonium chloride, DDACl and octaethylene glycol mono-n-hexadecyl ether, C(16)EO(8), On the crystallization of calcium oxalate from 0.3 molar sodium chloride solutions is discussed. Under the given experimental conditions the thermodynamically stable monohydrate, COM was the predominant crystal form. Both ionic surfactants inhibited growth and aggregation of COM and, by preferential adsorption at different crystal faces, induced different habit modifications. In addition, micellar solutions of SDS promoted crystallization of the metastable calcium oxalate dihydrate, GOD. The nonionic surfactant, C(16)EO(8), Stimulated nucleation and/or initial crystal growth of COM, most probably by providing active centers for heterogeneous nucleation.