A Multi-Pumping Flow System with Pulsed Fluidization to Evaluate Soil Capacity for Phosphate Adsorption

Abstract

Soils with high levels of iron and aluminum, thus negatively the phosphorous availability, affecting crop yields. A prior determination of the soil capacity to adsorb phosphate is relevant to attaining good agricultural performance. To this end, a multi-pumping flow system with pulsed fluidization is proposed. The procedure takes into account the amount of remaining phosphorus (P-rem) in the solution after the adsorption step to indirectly estimate the soil retention capacity. A 1.0 mg L -1 P solution is passed through a fluidized bed column with 50 mg of soil (particles < 0.15 mm), where the analyte is adsorbed. P-rem was spectrophotometrically quantified by the molybdenum blue method.

Solid-phase extractions in flow analysis

“…Additionally to analyte separation and concentration, monitoring of desorbed chemical species has been proposed for e.g. bio-accessibility assays (Vida et al 2016), estimative of nutrient release from soils (Machado et al 2017), and speciation analysis (Pons et al 2005).…”