Surface charge and wetting characteristics of layered silicate minerals.

The surface characteristics, including surface charge and wettability, of layered silicates are reviewed based on experimental results and molecular dynamics simulation (MDS) results. The surface charge features of important layered silicates including mica, talc, and kaolinite are described from atomic force microscopy (AFM) measurements, electrophoresis measurements, and/or results from potentiometric titration. In addition, the wetting characteristics of the silica tetrahedral surface which is common to all layered silicates are examined with different experimental techniques and results are discussed. The wettability of trilayer silicates and bilayer silicates is discussed, particularly the wettability of the silica tetrahedral face and alumina octahedral face of kaolinite based on MDS results as well as recent AFM results.