Other
Scientific paper
Sep 1996
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1996gecoa..60.3363l&link_type=abstract
Geochimica et Cosmochimica Acta, vol. 60, Issue 18, pp.3363-3373
Other
Scientific paper
Potentiometric titration behavior and the effects of dissolution on the titration experiment of a complex natural clay mineral, glauconite, were investigated and interpreted according to surface complexation theory. Considerable dissolution was detected in the time frame of the titration experiments, with the amount of individual cations released from glauconite a function of solution variables and dissolution kinetics. Dissolution effects can be accounted for in model simulations of titration behavior by considering hydrolysis of these cations. Proton surface charge can be calculated by subtracting supernatant titration curves from those of glauconite suspension. Surface complexation models were used to describe titration data. The nonelectrostatic model (NEM) and constant capacitance model (CCM) were implemented using single-site, single-site with dissolution correction, and multi-site with dissolution correction approaches. CCM typically produced better fits of experimental data than NEM based on a statistical fitting parameter. In general, model descriptions are good for background electrolyte concentration 0.01 M. In most instances, the correction for dissolution effects yielded a modest improvement in model simulation of experimental data over that obtained by a simple single-site model, but complexity of the model calculations increases greatly when the numerous additional chemical reactions are considered. Incorporation of ion exchange interactions produced no substantive improvement over the other approaches. Consistent with these results, speciation calculations indicate that the > X OH group dominates over other surface species in the pH range of interest, and surface protonation-deprotonation are the most influential reactions with respect to the surface chemistry of the mineral.
Lu Weiping
Smith Edward H.
No associations
LandOfFree
Modeling potentiometric titration behavior of glauconite does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Modeling potentiometric titration behavior of glauconite, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Modeling potentiometric titration behavior of glauconite will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1462679