Pressure on groundwater resources has increased during the last decades due to the growing demand, especially in arid and semiarid regions, such as the Mediterranean basin, with frequent drought periods. In order to partially remediate this environmental problem of world concern, irrigation of agricultural lands with adequately treated wastewaters (TWW) is becoming a common management practice. The complex composition of these low-quality waters may influence the behavior of organic contaminants in soils. A calcareous soil with low organic carbon content was selected for the assessment of the adsorption and leaching of the neonicotinoid insecticide thiacloprid (THC). Different solutions were evaluated: TWW after a secondary treatment, a saline solution and solutions with a range of dissolved organic carbon concentration (DOC, 3-300mgL). The addition of an organic fertilizer (fertiormont) to the soil was also assessed, in an attempt to reduce THC mobility. Sorption of thiacloprid, a relatively polar pesticide, was similar under all the conditions considered, though an adsorption decrease was observed when DOC concentration increased. The transport of THC through soil columns was retarded with all the treatments, with the lower effects corresponding to TWW and the saline solution. Addition of fertiormont and irrigation with DOC at 3mgL resulted in a reduction of pesticide leached (34% and 38%, respectively) in comparison with the control (66%), but surprisingly not for DOC at high concentration (55%), possibly due to co-elution of the pesticide with DOC. Therefore the transport of polar compounds, like THC, could be affected by the composition of the irrigation solutions, altering their impact to environmental water resources.
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http://dx.doi.org/10.1016/j.scitotenv.2017.08.028 | DOI Listing |
Environ Geochem Health
January 2025
School of Chemical & Environmental Engineering, China University of Mining and Technology-Beijing, Beijing, 100083, China.
As a typical ecologically fragile area, the Wudong Coal Mine region in Xinjiang generates large accumulations of coal gangue each year, which, in the alkaline soil environment, can easily lead to significant leaching and accumulation of As. This study developed a stabilizer (CFD) using cement, fly ash, and desulfurized gypsum to modify in-situ soil in the Xinjiang mining area, resulting in a modified solidified soil with excellent geotechnical performance and As stabilization capability. The study results showed that when CFD content exceeded 14.
View Article and Find Full Text PDFSci Total Environ
January 2025
Korea Mine Rehabilitation and Mineral Resources Corporation, Wonju, Gangwon-do 26464, Republic of Korea.
Tracing the sources of each contaminant and its geochemical reactions requires a variety of geochemical tools. In this study, chemical compositions and isotopic ratios of O-H, Mo, and Zn were utilized to identify the sources and geochemical reactions of water, As, Mo, and Zn in the seepage from a mine tailings dump. The distinct chemical compositions observed between the seepage and monitoring well, along with the O-H isotopic ratios, suggested that the seepage originated from creek water rather than nearby groundwater, which was supported by a large seasonal variation of δMo in both the seepage and creek.
View Article and Find Full Text PDFPhys Chem Chem Phys
January 2025
School of Chemistry & Chemical Engineering, South China University of Technology, Guangzhou 510640, P. R. China.
The hydrogenation of bicarbonate, a byproduct of CO captured in alkaline solutions, into formic acid (FA) using glycerol (GLY) as a hydrogen source offers a promising carbon-negative strategy for reducing CO emissions. While Pd-based catalysts are effective in this reaction, they often require high temperatures, leading to low FA yield due to strong hydrogen adsorption on Pd surfaces. In this work, metal-organic framework derived N-doped carbon encapsulated CoNi alloy nanoparticles (CoNi@NC) were prepared, acid-leached, and employed as a support to modulate the electronic structure of Pd-based catalysts.
View Article and Find Full Text PDFJ Colloid Interface Sci
January 2025
Key Laboratory of Fine Chemicals of College of Heilongjiang Province, Qiqihar University, Qiqihar 161006, China; School of Materials Science and Engineering, Jiamusi University, Jiamusi 154007, China. Electronic address:
Most transition metal-based electrocatalysts, when used for the oxygen evolution reaction (OER), undergo significant restructuring under alkaline conditions, forming localized oxides/hydroxides (MOOH), which act as the real active centers, activating adjacent metal sites and creating new active sites that enhance electrocatalytic behavior. Nevertheless, inducing rapid and in-depth self-reconstruction of catalyst surfaces remains a huge challenge. Herein, this work achieves rapid and in-depth self-reconstruction by doping fluorine into the lattice of transition metal oxides (MO).
View Article and Find Full Text PDFSci Total Environ
January 2025
School of the Environment, University of Queensland, QLD, Australia.
The transition to net zero emissions requires the capture of carbon dioxide from industrial point sources, and direct air capture (DAC) from the atmosphere for geological storage. Dissolved CO has reactivity to rock core, and while the majority of previous studies have concentrated on reservoir rock or cap-rock reactivity, the underlying seal formation may also react with CO. Drill core from the underlying seal of a target CO storage site was reacted at in situ conditions with pure CO, and compared with an impure CO stream with SO, NO and O that could be expected from hard to abate industries.
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