Effects of lignin on crystallization of calcium carbonate.

Based on the basic principles of biomineralization,the effects of lignin concentration and system temperature on the growth of CaCO3 crystals were studied.Moreover,the structure,appearance and thermal decomposition properties of CaCO3 were characterized by FT-IR,SEM,XRD and TG.The results demonstrated that CaCO3 formed in lignin solution was calcite,displaying dumbbell-shaped,spherical,oval or football-shaped appearance,which was different from that formed in pure water.Lignin concentration and system temperature had significant impact on the crystal morphology.During the course of crystallization,CaCO3 and lignin had mutual interaction,and the possible mechanism had been discussed.