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

Author(s)

Machado, Jeane M. C. ; Melchert, Wanessa R. ; Zagatto, Elias A. G. ; Kamogawa, Marcos Y.

• Document type: Journal article
• Source: Journal of the Brazilian Chemical Society; v. 28, n. 7, p. 1149-1157, JUL 2017.
• Web of Science Citations: 2

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. The coefficient of variation (n = 20), limits of detection and quantification (99.7% confidence level), and sampling rate were estimated as 1.54%, 17 and 51 µg L-1 P, and 87 h-1, respectively. Only 0.27 mg (NH4)6Mo7O24 and 0.10 mg SnCl2 were consumed per determination, generating 2.4 mL of waste. The results followed a linear relationship [y = 0.9702x + 1.483 (r = 0.9635; n = 20)] with the reference procedure. In comparison to the reference procedure, 100, 40 and 180-fold reductions in the required soil amount, waste generation and analytical time were attained. (AU)

• FAPESP's process: 13/00524-0 - Performance of extraction systems and flow analysis in exploring pulsed flow and fluidized bed
• Grantee: Jeane Maria Cunha Machado
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 11/19944-3 - Use of construction and demolition waste as substrates for plant
• Grantee: Marcos Yassuo Kamogawa
• Support Opportunities: Regular Research Grants
• FAPESP's process: 12/08205-8 - Strategies for in situ sampling of macronutrients and micronutrients of soil
• Grantee: Marcos Yassuo Kamogawa
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/23498-9 - Advanced flow systems for technological, agronomical and environmental analysis
• Grantee: Elias Ayres Guidetti Zagatto
• Support Opportunities: Research Projects - Thematic Grants