Quantitative Analysis of The Inorganic Content in Aqueous Solutions Based on Selective Membrane Dialysis and Electric Current Measurement

Abstract

Quantitative chemical analysis of ion species in aqueous solutions is performed. It is
based on dialysis in an aqueous solution with ion exchange membranes and indication of the
dialysis process by galvanic current created in a dialysis cell having one or two membranes. An
analyte solution is set on one side of the membrane(s) and water on the other side of the
membrane(s). A standard solution of the species under investigation is added to a measured
volume of the water in a stepwise manner. Thus a solution with known concentration is created
after every single addition of the standard solution. Different concentration gradients of analyte
species form across the membrane(s) in this way. The analyte concentration is determined by
finding graphically the standard solution volume corresponding to the zero concentration
gradient. Five different modifications of the method are developed allowing analysis of
concentrated solutions, fast or more accurate and precise determination, as well as pH
determination. The method can be applied to the analysis of mineral content in sea water,
mineral water and sylvenite.