Thermodynamic model for sorption of bivalent heavy metals on calcite in natural-technogenic environments

Abstract

Approaches to the construction of thermodynamic models for sorption of trace-element cations on carbonates are considered. To calculate thermodynamic equilibria by the method of Gibbs free-energy minimization, the existing database of reaction constants and thermodynamic potentials was extended. Different types of models are illustrated by the example of precipitation of Cd, Cu, Pb, and Zn from the water of a drainage stream flowing out of the impoundment of barite-polymetallic ore-dressing wastes. It is shown that the mobility of metals in such cases can be controlled by their sorption by calcite present in bottom sediments and suspension. Any approach can be successfully applied to both the modeling of experimental data on cation sorption and the prediction of the ecologo-geochemical situation in the districts of dressing works.

Electrochemical method for isolation of chitinous 3D scaffolds from cultivated Aplysina aerophoba marine demosponge and its biomimetic application

“…Indeed, natural calcite as limestone [109] or in the form of waste chicken eggshells [110] has been used for heavy metal removal. In comparison with other calcium carbonate polymorphs, calcite represents the highest affinity to lead (Pb 2+ ) [111] and cadmium (Cd 2+ ) [112] ions. Also, a high ability of calcite for the remediation of arsenic (As) contamination from water solutions was reported [105,106,113].…”

The HydroGeo Software Package and Its Usage

“…Key problems related to formation of highly mineralized underground brines, sodium-, iron-, arsenic-bearing water and other types of water have been solved. New methods of mobilization and concentrating of Au, U, As, F, Fe, Al, P, Sr have been revealed and some aspects of the theory concerning formation of stratified, ferromanganese, percolated uranium and placer gold deposits have been updated [7][8][9][10][11][12][13][14][15].…”

Modelling of the dissolution and reprecipitation of uranium under oxidising conditions in the zone of shallow groundwater circulation

“…The HydroGeo model has been extensively tested against comparable international models, including the HMV model (Harvie et al 1984, Bukaty 2005b. The use of the software HydroGeo for solving various problems has demonstrated earlier by Shvartzev & Dutova (2001), Dutova et al (2006), Gaskova et al (2009), Dutova & Nikitenkov (2010), and Balobanenko et al (2016).…”