Structural control of the non-ionic surfactant alcohol ethoxylates (AEOs) on transport in natural soils

Autor: L. Candela, Pablo A. Lara-Martín, Carmen Corada-Fernández, M. García-Delgado, M. Botella Espeso, Eduardo González-Mazo, Joaquin Jimenez-Martinez
Přispěvatelé: Química Física
Jazyk: angličtina
Rok vydání: 2021
Předmět:
Zdroj: Environmental Pollution 269 (2021) 116021
RODIN. Repositorio de Objetos de Docencia e Investigación de la Universidad de Cádiz
instname
Repositorio Institucional del Instituto IMDEA Agua
Instituto IMDEA Agua (IMDEA AGUA)
Universidad de Cantabria (UC)
Environmental Pollution, 269
RODIN: Repositorio de Objetos de Docencia e Investigación de la Universidad de Cádiz
Universidad de Cádiz
ISSN: 0269-7491
1878-2450
1873-6424
DOI: 10.1016/j.envpol.2020.116021
Popis: Surfactants, after use, enter the environment through diffuse and point sources such as irrigation with treated and non-treated waste water and urban and industrial wastewater discharges. For the group of non-ionic synthetic surfactant alcohol ethoxylates (AEOs), most of the available information is restricted to the levels and fate in aquatic systems, whereas current knowledge of their behavior in soils is very limited. Here we characterize the behavior of different homologs (C12–C18) and ethoxymers (EO3, EO6, and EO8) of the AEOs through batch experiments and under unsaturated flow conditions during infiltration experiments. Experiments used two different agricultural soils from a region irrigated with reclaimed water (Guadalete River basin, SW Spain). In parallel, water flow and chemical transport were modelled using the HYDRUS-1D software package, calibrated using the infiltration experimental data. Estimates of water flow and reactive transport of all surfactants were in good agreement between infiltration experiments and simulations. The sorption process followed a Freundlich isotherm for most of the target compounds. A systematic comparison between sorption data obtained from batch and infiltration experiments revealed that the sorption coefficient (Kd) was generally lower in infiltration experiments, performed under environmental flow conditions, than in batch experiments in the absence of flow, whereas the exponent (β) did not show significant differences. For the low clay and organic carbon content of the soils used, no clear dependence of Kd on them was observed. Our work thus highlights the need to use reactive transport parameterization inferred under realistic conditions to assess the risk associated with alcohol ethoxylates in subsurface environments.
Environmental Pollution, 269
ISSN:0269-7491
ISSN:1878-2450
ISSN:1873-6424
Databáze: OpenAIRE
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