Sorption and catalytic oxidation of Fe(II) at the surface of calcite

Removal of Fe(II) from groundwater via aqueous portlandite carbonation and calcite-solution interactions

“…This also indicates that the presence of Fe +2 in contact with calcite surfaces promotes calcite dissolution sites during its oxidation and co-precipitation onto calcite surfaces. In other words, calcite particles catalyze the iron oxidation at the calcite-solution interfaces via calcite dissolution, as already described in Mettler et al [17]. Finally, the removal kinetics is directly dependent on the initial iron concentration, as displayed in Figure 2a.…”

“…Mettler et al [17] have demonstrated that calcite dissolution catalyzes the oxidation of ferrous iron and its co-precipitation as ferric oxyhydroxide at the calcite-solution interfaces. They …”

“…However, the carbonation method may be triply-efficient because (1) other toxic ions (Se, As, Cd, Cu, Cr, etc.) can be removed during portlandite carbonation by incorporation and/or co-precipitation [25,42] (2) powdered portlandite or calcium hydroxide in water prior to a carbonation process increases the pH to 12.4, which can acts as a softening agent in the water being treated Application of calcareous materials (natural or synthetic) to treat ferrous contaminated groundwater has been pointed out by various researchers [15,[17][18][19][20]. All studies argue that the limestone provides high potential and effectiveness, low cost and ease of use.…”

“…Moreover, this method is relatively inexpensive compared to other treatment techniques [16][17][18][19][20]. To our knowledge, no attempt has been made to remove Fe (II) from simulated groundwater via mineral aqueous carbonation of portlandite.…”

Origin of high Zn contents in Jurassic limestone of the Jura mountain range and the Burgundy: evidence from Zn speciation and distribution

“…In that case, due to the high degree of water mixing in oolitic shoal environments, a homogeneous Zn distribution or at least the presence of Zn in all limestone components would be expected, with adsorption and incorporation of Zn into oolites. In sorption-dissolution experiments at room temperature, solid-state diffusion of adsorbed Zn and Fe into calcite particles have been reported to occur at rates of tens of angstroms to tens of nanometers per week (Mettler et al 2009;Stipp et al 1998). Assuming an average oolite radius of 0.8 mm for the investigated limestone, diffusion of Zn and Fe to the nucleus of pre-existing oolites may be expected within 1,500-15,000 years.…”