Haloacetaldehydes (HAs) are the third prevalent group of disinfection by-products of great health concern. A bench-scale study was performed to investigate the formation and speciation of HAs in raw and treated waters after chlorination and ozonation-chlorination. Pre-ozonation resulted in enhanced HA formation during subsequent chlorination, and the HA yields from ozonation-chlorination were 1.66 and 1.63 times higher than that from chlorination of raw and treated waters. The mechanism about the increase of HA formation during ozonation-chlorination was systematically investigated in this study. The results showed that acetaldehyde formed after ozonation was the dominant precursor for the enhanced HA formation during subsequent chlorination. Increase in pH and chlorine dose increased HA formation during acetaldehyde chlorination. Based on the kinetic studies on the HA formation during acetaldehyde chlorination and the HA stabilities with and without free chlorine, it was found that chlorine was incorporated into the α-hydrogen in acetaldehyde to form a sequence of mono-, di- and tri-chloroacetaldehyde. During this process, these three chlorinated acetaldehydes would also undergo base-catalyzed hydrolysis through decarburization and dehalogenation pathways. This study elucidated that acetaldehyde formed after ozonation resulted in the increase of HA formation during subsequent chlorination. This study also revealed the formation pathway of HA during chlorination of acetaldehyde, which would help to minimize HA formation at drinking water plants.
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http://dx.doi.org/10.1016/j.chemosphere.2019.124361 | DOI Listing |
ACS Nano
January 2025
Department of Paediatrics & Adolescent Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China.
Melanoma is the most aggressive type of skin cancers. Traditional chemotherapy and radiotherapy have limited effectiveness and can lead to systemic side effects. Photodynamic therapy (PDT) is a photoresponsive cancer therapy based on photosensitizers to generate reactive oxygen species (ROS) to eradicate tumor cells.
View Article and Find Full Text PDFChemSusChem
January 2025
Spanish Scientific Research Council: Consejo Superior de Investigaciones Cientificas, Metalurgia Primaria y Reciclado de Materiales, SPAIN.
This work aims to recover rare earths from wind turbines NdFeB magnets through pyrometallurgical and hydrometallurgical techniques. First, a NdFeB hydride powder is obtained by decrepitation with hydrogen. Subsequently, this powder was subjected to a chlorination roasting process and successive leaching with water to bring the metals into solution.
View Article and Find Full Text PDFMembranes (Basel)
December 2024
Group of Analysis & Processes, Faculty of Sciences, University of Angers, 2 Bd. A. de Lavoisier, 49045 Angers, Cedex 01, France.
The objective of this study is to evaluate the degradation of end-of-life BWRO membranes sourced from a factory in France by analyzing their water permeability, roughness, and chemical composition in order to diagnose the level of degradation incurred during their first life cycle in water softening. Following this, two new applications for the end-of-life BWRO membranes were investigated: (i) as ultrafiltration membranes (UF) for domestic effluent treatment and (ii) as cation exchange membranes (CEM) for use in fungal microbial fuel cells (FMFC). The UF membrane was renovated with an acetic acid treatment and, subsequently, used for domestic effluent filtration.
View Article and Find Full Text PDFJ Environ Manage
January 2025
College of Animal Science and Technology, Jilin Agricultural University, Changchun, 130118, China. Electronic address:
Humans can be exposed to LCCPs through air and diet, leading to their accumulation in the body. Given the significance of understanding potential health risks, a thorough investigation into the detrimental health impacts of LCCPs is paramount. In this study, we conducted a series of experiments to investigate the effects of LCCPs on cardiomyocytes, employing techniques such as flow cytometry, western-blot, indirect immunofluorescence, and confocal microscopy.
View Article and Find Full Text PDFCarbohydr Polym
March 2025
Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China; Institute of Chemical Industry of Forest Products, Chinese Academy of Forestry (CAF), No 16, Suojin Wucun, Nanjing, China. Electronic address:
Achieving effective interfacial compatibility between hydrophilic cellulose nanofibrils (CNFs) and hydrophobic vegetable oil polymers (VOPs) remained a significant challenge. To address this issue, we developed a one-component nanocomposite (OCN) based on hyperbranched CNF-grafted VOPs. Rigid precursor initiator poly (vinylbenzyl chloride) (PVBC) was first grafted onto the CNF surface via phase-transfer catalysis, forming a branched macroinitiator (CNF-g-PVBC) with chlorine contents ranging from 4.
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