Adsorption of phosphate on calcite

Arsenate uptake by calcite: Macroscopic and spectroscopic characterization of adsorption and incorporation mechanisms

“…Dual uptake kinetics have been documented in studies of arsenate sorption onto other mineral substrates (e.g., Fuller et al, 1993;McGeehan and Naylor, 1994;O'Reilly et al, 2001;Simeoni et al, 2003;Arai et al, 2004;Genç-Fuhrman et al, 2004), as well as for phosphate and metal uptake by calcite (e.g., House, 1990;House and Donaldson, 1986;Suzuki et al, 1986;van der Weijden et al, 1997). In studies dealing with calcite, the fast initial uptake step has commonly been interpreted as chemisorption to readily available surface sites, whereas the following slow removal is sometimes assumed to represent surface precipitation or coprecipitation (e.g., Kitano et al, 1976;McBride, 1979McBride, , 1980Franklin and Morse, 1983).…”

“…The partitioning of As(V) between the solid and liquid phase can be quantified by defining a distribution coefficient, K d , as used in past studies addressing phosphate adsorption to calcite (Reddy, 1977;House and Donaldson, 1986;Suzuki et al, 1986). Distribution coefficients are dependent on experimental parameters such as pH, ionic strength, reaction time, and solution composition, as well as on the species defined to be the adsorbing species, e.g., AsO 4 3À or HAsO 4 2À , the latter being the dominant aqueous As(V) species under the reaction conditions used in our experiments (Table 2).…”

Kinetic study on phosphate removal from aqueous solution by biochar derived from peanut shell as renewable adsorptive media

“…3b. It is well known that calcite (CaCO 3 ) can act as phosphate adsorbent, thereby influencing the phosphate sorption or desorption fluxes (Sø et al 2011;Suzuki et al 1986). With respect to pH condition, the phosphate adsorption efficiency could be increased with increasing pH condition due to inverse correlation between Ca 2?…”

A 31P and 1H MAS NMR study of phosphate sorption onto calcium carbonate

“…Other studies, also based on solubility measurements, found that the phosphate in solution is in equilibrium with a surface complex, Ca3(HCO3)3PO4 (22,23). Suzuki et al (24), using labeled 32p as the tracer, found that unprotonated PO~-was preferentially sorbed onto the calcite surface even at a solution pH where protonated phosphate species predominated in solution. House and Donaldson (8), studying the adsorption and coprecipitation of P on calcite, found no evidence of a distinct calcium-phosphate solid phase that controls the P solution composition.…”