Abstract:

In order to provide reference for the controllable preparation and application of calcium carbonate,calcium car-bonate was prepared with CaCl₂ and Na₂CO₃ as raw materials and different types of lignin based surfactant as control agents,and the crystal form and morphology of calcium carbonate were studied.The results showed that the crystal type of calcium carbonates prepared with different type of control agents were same as that prepared in pure water system.All of them were calcite type,but their microscopic morphology and properties were different.The calcium carbonate prepared in pure water system had smooth surface and uniform size.While for the calcium carbonates prepared with control agents,the surface had pinhole,the edges and corners were no longer distinct,and the dispersibility increased,especially that prepared with lignin-based quaternary ammonium salt.The more control agent was used,the smaller and more the pores was on the surface of calci-um carbonate,and the thickness of sheet became thinner.The addition of control agents led to porous surface,weakened edges and corners,increase of porosity and dispersion and easier thermal decomposition of calcium carbonate.They had potential application in fillers,drug carriers,templates for material preparation,adsorbents,etc.

Key words: lignin, surfactant, calcium carbonate