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Application of Rotating Coiled Columns to the Fractionation of Soil Particles and to the Sequential Extraction of Heavy-Metal Species from Silty, Dusty, and Sandy Fractions

“…As was mentioned above, a number of regularities in the behavior of solid particles in RCCs was studied previously using latex and silica-gel particles of nonspherical shape as an example [7,12]. It was shown that the fractionation of a solid sample depends on the design and working parameters of the centrifuge: the type of the kinematic scheme of the planetary gear, the inner diameter of the capillary, the speed of rotation of the centrifuge, the directions of rotation and pumping of the mobile phase, and the inner surface of the column capillary.…”

“…The regularities of the behavior of particles in a column were studied using the separation of model spherical particles (latexes and silica gels) and natural nonspherical particles of quartz sand as an example [10,11]. The advantage of using RCCs for the determination of the speciation of metals as compared to the conventional sequential extraction procedure was also demonstrated [7,12]. The extraction of various metal species was performed by the Kerstner-Forstner procedure (a version of the Tessier procedure), according to which the following microelement species were extracted: the exchange form, the "carbonate" form, elements bound with manganese oxides, elements bound with iron and aluminum oxides, and the sulfideorganic form [8].…”

ICP-MS for the analysis at the nanoscale – a tutorial review

“…131 In FFF sample fractionation is performed inside a trapezoidal channel without a stationary phase and is the only technique that offers a continuous, high size-resolution fractionation from about 1 nm up to several µm. 39 Briefly, most of the FFF subtechniques comprise channel dimensions of 20-50 cm length, 2-3 cm width and 0.01-0.05 cm in thickness; 132 (alternatively, and mentioned for the sake of completeness, FFF in rotating coiled columns has also been described in few studies 133,134,135,136 ). A pumped carrier liquid is moving the analytes/particles from the "inlet side" to the "outlet/detector side" generating a parabolic flow profile.…”

Fractionation and Determination of Different Lead Species in Contaminated Soils

“…A basically new approach to fractionating element species differing in their mobility and biological availability in soils, silts, and bottom elements based on the use of rotating coiled columns (conventionally used in countercurrent liquid chromatography) was proposed [12,13]. The analysis of the McLaren-Crawford and Kersten-Forstner procedures has shown that, in spite of the slow kinetics of element extraction from solid samples, the use of multistep extraction in a rotating coiled column (RCC) reduces the contact time between the liquid and solid phases necessary for separating each species to 30-50 min.…”