M. Kosmulski et al., Specific adsorption of nickel and zeta potential of silica at various solid-to-liquid ratios, J COLL I SC, 220(1), 1999, pp. 128-132
The electrokinetic curves of silica obtained at given total concentrations
of heavy metal cations depend on the solid-to-liquid ratio; namely, at low
solid-to-liquid ratios the sign of the zeta potential of silica is reversed
to positive at relatively low concentrations of heavy metal cations, while
at higher solid-to-liquid ratios the electrokinetic curves are not substan
tially influenced at much higher concentrations. The surface complexation m
odel fails to properly reflect the Ni effect on the course of electrokineti
c curves of silica. The course of electrokinetic curves [positions of the i
soelectric point(s) and of the maxima in mobility] is correlated with a lin
ear combination of the surface charge density in the absence of heavy metal
cations at given ionic strength and the adsorption density of Ni. (C) 1999
Academic Press.