Studies on the membrane potentials of some imperfect clay and shale membranes

[摘要] The membrane potentials of three imperfect shale membranes were measured for a number of electrolytes. The transference numbers of ions within the membranes were determined in an apparatus which is described. Membrane potentials were calculated from the equation. General agreement between measured and calculated values was obtained, although the former were consistently lower than the latter, due to the mosaic character of the membranes. The order of calculated relative mobilities of adsorbed cations within the membranes studied. The membrane potentials of natural bentonite and hydrogen-bentonite membranes were measured as a function of the water content of the membranes. As the water content was decreased, the membrane potential was observed to increase, reflecting a closer packing of the clay particles. The data for hydrogen-bentonite support the conclusion that free (non-adsorbed) hydrogen ions lose their abnormal mobility within a membrane in which water is oriented.

[发布机构] Rice University