ESCA-studies on activated silicagel surfaces preconcentrating heavy metal ions

Summary The theoretical ion-exchange capacity of an aminosilylated silicagel surface loaded with dithiocarbamate (DTC) groups was calculated by correlation of the results of a BET measurement, a quantitative determination of the concentration of reactive single hydroxyl groups on the surface, and ESCA intensities. ESCA spectra suggest many functional groups to be thiuram disulfide ones and not DTC ones as believed before. Quantitative ESCA measurements show that aminosilylated silicagel surfaces are only partially transformed to the DTC form. In spite of their chemical instability, the concentration of heavy metal ions (Pb²⁺) in aqueous solution and their ESCA intensities after immobilization on the activated silicagel surface are linearily correlated with each other in the ppm region.Professor Dr. Carl Mahr zum 80. Geburtstag in Dankbarkeit gewidmet.