Browsing by Author "Escudey, Mauricio"
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- ItemAdvancements in the Synthesis of Building Block Materials: Experimental Evidence and Modeled Interpretations of the Effect of Na and K on Imogolite Synthesis(2017) Arancibia Miranda, Nicolás; Escudey, Mauricio; Ramírez Leiva, Ricardo; González, Rafel I.; Van Duin, Adri C. T.; Kiwi Tichauer, Miguel Germán
- ItemApplication of Polypyrrole/Humic Acid Composite Electrode for Copper Ion Extraction from Drinking Water(2012) Antilén Lizana, Mónica; Guzmán de la Cerda, Diego José Edgardo; Valle de la Cortina, María Angélica del; Río Quero, Rodrigo del; Letelier Solar, María Victoria; Lagos, Gustavo; Escudey, Mauricio; Pizarro, Carmen
- ItemChanges on chemical fractions of heavy metals in Chilean soils amended with sewage sludge affected by a thermal impact(2006) Antilén Lizana, Mónica; Araya, Nadia; Briceno, Margarita; Escudey, Mauricio
- ItemDistribution of contaminant trace metals inadvertently provided by phosphorus fertilisers: movement, chemical fractions and mass balances in contrasting acidic soils(2018) Molina Roco, Mauricio; Escudey, Mauricio; Antilén Lizana, Mónica; Arancibia Miranda, Nicolás; Manquian Cerda, Karen
- ItemEffect of ash from forest fires on leaching in volcanic soils(2015) Escudey, Mauricio; Arancibia Miranda, Nicolás; Pizarro, Carmen; Antilen, Mónica
- ItemEffect of ash from forest fires on phosphorus availability, transport, chemical forms, and content in volcanic soils(2010) Escudey, Mauricio; De la Fuente, Pamela; Antilén Lizana, Mónica; Molina Roco, Mauricio
- ItemEffect of biosolids on the organic matter content and phosphorus chemical fractionation of heated volcanic Chilean soils(2008) Antilén Lizana, Mónica; Briceno, Margarita; Galindo Griffith, Gerardo; Escudey, Mauricio
- ItemImpact of forest fire ash on surface charge characteristics of andisols(LIPPINCOTT WILLIAMS & WILKINS, 2007) Molina, Mauricio; Fuentes, Roxana; Calderon, Raul; Escudey, Mauricio; Avendano, Katherine; Gutierrez, Marlen; Chang, Andrew C.Forest fires are a common occurrence in central southern Chile where soils are mostly Andisols. The ash deposits may alter the chemical properties of the soils in the burned areas and nearby agricultural lands. In a column experiment, three Andisols found in this region were treated with 2-cm-thick ash deposit on the surface and leached with 12 pore volumes of water for 3 months. At the end of the leaching, the ashtreated and their respective control soils were sectioned, and the surface charge characteristics of each soil section were determined by electrophoretic mobility test and potentiometric titration. Chemical constituents released from the ash affected mainly the surface 0- to 5-cm section of the soils. The ash treatment and leaching caused the soil pH of the 0-to 5-cm section to increase from 2 to 3 pH units. Consequently, the negative surface charge and cation exchange capacity of affected soils both increased. The ash treatment changed the isoelectric point when the isoelectric point of respective control soil section was > 3. The point of zero salt effect and the point of zero net proton charge of the ashtreated soils were increased in the 0- to 5-cm section and the influences of the ash leachates gradually diminished with soil depths. The alkaline leachates dissolved and mobilized the soil organic carbon and associated soil constituents. The effects observed on the surface charge and dissociation constants are consistent with anion and/or dissolved organic carbon adsorption. The surface dissociation constants, estimated by the constant capacitance model, showed that the ash treatment caused modifications of the active sites on the soil particles. Although ash leachates increase the cation retention capacity, the adsorption of other cations may be adversely affected by the ash deposit that is rich in Ca2+ and K+.
- ItemRole of Organic Matter, Iron Oxides and Aluminosilicate Content on Physicochemical Interactions between Ciprofloxacin and Andisol Soil(HUMANA PRESS INC, 2025) Urdiales, Cristian; Varas Gutiérrez, Mauricio Janssen; Suazo-Hernández, Jonathan; Pizarro, Carmen; Escudey, Mauricio; Caceres-Jensen, Lizethly; Antilen Lizana, Mónica PaulinaPurpose The widespread use of antibiotics to treat infectious diseases in humans and animals has raised signifcant environmental concerns due to their presence in soils. The interaction between natural aluminosilicates such as allophane, both with and without iron oxides (FexOy) and organic matter (OM) coatings, in the adsorption of Ciprofoxacin (CIP) remains still unexplored. The objective of this study is to establish the role of diferent soil components, OM and FexOy, in the adsorption of CIP in soils. Methods Santa Bárbara (SB) series soil and chemically treated substrates without OM (SB1) and without OM and FexOy (SB2) were characterized. All CIP adsorption studies were conducted through batch experiments in an electrochemical cell, by using square wave voltammetry to determine CIP concentration. Results Adsorption isotherms revealed two types of adsorption sites in the SB soil: instantaneous and time dependent. The Langmuir-Freundlich model explained cooperative adsorption, while the Freundlich model aligned with SB1 and SB2 samples. SB1 showed higher adsorption capacity but lower intensity than SB2. The removal of OM and FexOy notably infuences the adsorption behavior, resulting in lower capacities than the original SB soil. Conclusions This study emphasizes the complex interaction between CIP and soil components. The adsorption data highlights the strong binding of CIP to soil particles and substrates, suggesting a low leaching potential. The calculated GUS index of 2.758 further supports this, indicating a moderate leaching potential and reinforcing the importance of understanding the strength of CIP binding in environmental matrices. This knowledge is crucial for assessing its mobility and developing strategies to minimize its environmental impact.
- ItemRole of Organic Matter, Iron Oxides and Aluminosilicate Content on Physicochemical Interactions between Ciprofloxacin and Andisol Soil(Springer International Publishing AG, 2025) Urdiales, Cristian; Varas Gutiérrez, Mauricio Janssen; Suazo-Hernández, Jonathan; Pizarro, Carmen; Escudey, Mauricio; Caceres-Jensen, Lizethly; Antilen Lizana, Mónica PaulinaPurpose The widespread use of antibiotics to treat infectious diseases in humans and animals has raised signifcant environmental concerns due to their presence in soils. The interaction between natural aluminosilicates such as allophane, both with and without iron oxides (FexOy) and organic matter (OM) coatings, in the adsorption of Ciprofoxacin (CIP) remains still unexplored. The objective of this study is to establish the role of diferent soil components, OM and FexOy, in the adsorption of CIP in soils. Methods Santa Bárbara (SB) series soil and chemically treated substrates without OM (SB1) and without OM and FexOy (SB2) were characterized. All CIP adsorption studies were conducted through batch experiments in an electrochemical cell, by using square wave voltammetry to determine CIP concentration. Results Adsorption isotherms revealed two types of adsorption sites in the SB soil: instantaneous and time dependent. The Langmuir-Freundlich model explained cooperative adsorption, while the Freundlich model aligned with SB1 and SB2 samples. SB1 showed higher adsorption capacity but lower intensity than SB2. The removal of OM and FexOy notably infuences the adsorption behavior, resulting in lower capacities than the original SB soil. Conclusions This study emphasizes the complex interaction between CIP and soil components. The adsorption data highlights the strong binding of CIP to soil particles and substrates, suggesting a low leaching potential. The calculated GUS index of 2.758 further supports this, indicating a moderate leaching potential and reinforcing the importance of understanding the strength of CIP binding in environmental matrices. This knowledge is crucial for assessing its mobility and developing strategies to minimize its environmental impact.
- ItemSorption and Selectivity Sequences of Cd, Cu, Ni, Pb, and Zn in Single- and Multi-Component Systems in a Cultivated Chilean Mollisol(TAYLOR & FRANCIS INC, 2010) Molina, Mauricio; Manquian Cerda, Karen; Escudey, MauricioThe heavy-metal sorption ability of soils is one of the most important factors that determine the fate of these contaminants in this medium of the biosphere. When heavy-metal containing soil amendments are land applied, a multi-component soil-solution equilibrium may occur in which various metals compete simultaneously for the sorption sites on the soil particles. In order to determine the effect of competition among Cd, Cu, Ni, Pb, and Zn on sorption characteristics and the selectivity sequence of those heavy metals in a cultivated Mollisol of central Chile, batch sorption experiments were carried out in single- and multi-component systems. Heavy metal sorption isotherms in both types of system were well described by the Langmuir's equation. For all the metals evaluated, competition among them (multi-component system) decreased both the maximum sorption capacity, obtained from the Langmuir's isotherm, and the partition coefficient (Kd) compared to the single-component system. In addition, the simultaneous presence of the five metals promoted the sorption of Cd, and to a lesser extent of Ni, on more specific sorption sites of soil particles. Either in single- or multi-component system, Pb and Cu showed a higher selectivity and retention compared to Cd, Ni and Zn, which indicates that the later heavy metals would present a higher mobility in the soil-plant-water system. Since Langmuir's parameters and Kd were highly affected by competition for all heavy metals evaluated, the use of single-component parameters in modeling assessment might lead to an incorrect description of the transport and fate of these contaminants in receiving Mollisols.
- ItemStudy of Sorption Kinetics and Sorption-Desorption Models to Assess the Transport Mechanisms of 2,4-Dichlorophenoxyacetic Acid on Volcanic Soils(2021) Caceres-Jensen, Lizethly; Rodriguez-Becerra, Jorge; Garrido, Carlos; Escudey, Mauricio; Barrientos, Lorena; Parra-Rivero, Jocelyn; Dominguez-Vera, Valentina; Loch-Arellano, BrunoThe sorption behavior of 2,4-dichlorophenoxyacetic acid (2,4-D) in the abundant agricultural volcanic ash-derived soils (VADS) is not well understood despite being widely used throughout the world, causing effects to the environment and human health. The environmental behavior and risk assessment of groundwater pollution by pesticides can be evaluated through kinetic models. This study evaluated the sorption kinetics and 2,4-D sorption-desorption in ten VADS through batch sorption experiments. Differences in the sorption extent for the fast and slow phases was observed through the IPD model where 2,4-D sorption kinetics was controlled by external mass transfer and intra organic matter diffusion in Andisols (C1 not equal 0). We confirmed from the spectroscopic analysis that the carboxylate group directly drives the interaction of 2,4-D on Andisol soil. The MLR model showed that IEP, FeDCB, and pHxSilt are important soil descriptors in the 2,4-D sorption in VADS. The Freundlich model accurately represented sorption equilibrium data in all cases (Kf values between 1.1 and 24.1 mu g(1-1/n) mL(1/n)g(-1)) with comparatively higher sorption capacity on Andisols, where the highest hysteresis was observed in soils that presented the highest and lowest OC content (H close to 0).
- ItemSurfactant properties of humic acids extracted from volcanic soils and their applicability in mineral flotation processes(2018) Urdiales Flores, Cristián Gerardo; Sandoval, María P.; Escudey, Mauricio; Pizarro, Carmen; Knicker, Heike; Reyes Bozo, Lorenzo del Carmen; Antilén Lizana, Mónica
- ItemTrace Element Composition of Selected Fertilizers Used in Chile: Phosphorus Fertilizers as a Source of Long-Term Soil Contamination(TAYLOR & FRANCIS INC, 2009) Molina, Mauricio; Aburto, Fabian; Calderon, Raul; Cazanga, Marcia; Escudey, MauricioAnthropogenic activities like agriculture have resulted in increased concentrations of some trace elements of toxicological and environmental concern in soils. Application of fertilizers has been one of the major inputs of these contaminants to agricultural soils in developing countries. Twenty-two fertilizers, including straight nitrogen (N), phosphorus (P), potassium (K), and NK fertilizers and micronutrient sources, were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES)for arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), vanadium (V), and zinc (Zn). As expected, the trace element content of fertilizers was highly variable and related to the origin of the material. Phosphorus fertilizers, especially triple superphosphate, presented the highest As, Cd, Cu, Cr Ni, V and Zn concentrations. In some of these fertilizers, the Cr V and Zn contents reached values greater than 3475 mg kg(-1) of P, and the Cd content (up to 288 mg kg(-1) of P) was several times higher than the regulatory limits of different countries. Some micronutrient sources presented the highest concentrations of Mn and Pb. In the cases of N, K, and NK fertilizers, the trace element concentration was very low, sometimes below the detection limits. In some agricultural systems the input of trace elements such as As and Cd to the soil through P fertilizers application may be higher than the outputs through plant uptake and leaching; therefore the long-term use of these fertilizers may cause the trace element concentration to increase in the plow layer of agricultural soils.