M. Alkattan et al., EXPERIMENTAL STUDIES OF HALITE DISSOLUTION KINETICS - II - THE EFFECTOF THE PRESENCE OF AQUEOUS TRACE ANIONS AND K3FE(CN)(6), Chemical geology, 143(1-2), 1997, pp. 17-26
The dissolution rates of compressed halite powders were measured using
rotating disk techniques at constant halite saturation states and in
the presence of trace concentrations of aqueous F-, Br-, and I-. All e
xperiments were performed at 25 degrees C. The presence of each trace
anion decreased the overall halite dissolution rate and the degree of
inhibition increases with increasing anion concentration. The order of
constant concentration effectiveness in inhibiting rates is I- > Br-
> F-. Dissolution inhibition by these anions is interpreted to result
from their adsorption on the halite surface. Application of a combined
transition state theory/Langmuir adsorption model to these experiment
al results allows both the description of measured rates and their ext
rapolation to other solution compositions. In contrast, work on aqueou
s K3Fe(CN)(6) indicates that trace quantities of this electrolyte has
little effect on halite dissolution rates, except at relatively high e
lectrolyte concentration or high halite saturation state where Na3Fe(C
N)(6) precipitation occurs on the halite surface. (C) 1997 Elsevier Sc
ience B.V.