Pore characteristics and water absorption in a synthetic smectite clay

Information on size and shape of pores in layered silicates can be obtained via analysis of the relative scattered intensity for different scattering vectors. In this study the small-angle neutron scattering technique was used to investigate the synthetic clay Na-fluorohectorite. The anisotropically shaped pores showed an average correlation length ratio of about 1:2 between the direction of sedimentation and the direction perpendicular to this. The absorption of water, which can be controlled via the temperature and humidity of the surrounding air, consists both in the intercalation of water molecules between the clay platelets and the filling of the mesopores between the platelet stacks.