Describing Phosphorus Sorption Processes on Volcanic Soil in the Presence of Copper or Silver Engineered Nanoparticles

• Main Authors: Jonathan Suazo-Hernández, Erwin Klumpp, Nicolás Arancibia-Miranda, Patricia Poblete-Grant, Alejandra Jara, Roland Bol, María de La Luz Mora
• Format: Article
• Language: English
• Published: MDPI AG 2021-04-01
• Series: Minerals
• Subjects: adsorption; engineered nanoparticles; organic matter; phosphorus; nutrients; pollution
• Online Access: https://www.mdpi.com/2075-163X/11/4/373

Engineered nanoparticles (ENPs) present in consumer products are being released into the agricultural systems. There is little information about the direct effect of ENPs on phosphorus (P) availability, which is an essential nutrient for crop growthnaturally occurring in agricultural soils. The present study examined the effect of 1, 3, and 5% doses of Cu⁰ or Ag⁰ ENPs stabilized with L-ascorbic acid (suspension pH 2–3) on P ad- and desorption in an agricultural Andisol with total organic matter (T-OM) and with partial removal of organic matter (R-OM) by performing batch experiments. Our results showed that the adsorption kinetics data of H₂PO₄⁻ on T-OM and R-OM soil samples with and without ENPs were adequately described by the pseudo-second-order (PSO) and Elovich models. The adsorption isotherm data of H₂PO₄⁻ from T-OM and R-OM soil samples following ENPs addition were better fitted by the Langmuir model than the Freundlich model. When the Cu⁰ or Ag⁰ ENPs doses were increased, the pH value decreased and H₂PO₄⁻ adsorption increased on T-OM and R-OM. The H₂PO₄⁻ desorption (%) was lower with Cu⁰ ENPs than Ag⁰ ENPs. Overall, the incorporation of ENPs into Andisols generated an increase in P retention, which may affect agricultural crop production.