Abstract
This work addresses the rehabilitation of water contaminated with atrazine, entrapping it in a permeable and sustainable barrier designed with waste materials (sepiolite) and with biomaterials (cork and pine bark). Atrazine adsorption was assessed by kinetics and equilibrium assays and desorption was tested with different extraction solvents. Adsorbed atrazine was 100% recovered from sepiolite using 20% acetonitrile solution, while 40% acetonitrile was needed to leach it from cork (98%) and pine bark (94%). Continuous fixed-bed experiments using those sorbents as PRB were performed to evaluate atrazine removal for up-scale applications. The modified dose-response model properly described the breakthrough data. The highest adsorption capacity was achieved by sepiolite (23.3 (±0.8) mg/g), followed by pine bark (14.8 (±0.6) mg/g) and cork (13.0 (±0.9) mg/g). Recyclability of sorbents was evaluated by adsorption-desorption cycles. After two regenerations, sepiolite achieved 81% of atrazine removal, followed by pine with 78% and cork with 54%. Sepiolite had the best performance in terms of adsorption capacity/stability. SEM and FTIR analyses confirmed no significant differences in material morphology and structure. This study demonstrates that recycling waste/biowaste is a sustainable option for wastewater treatment, with waste valorization and environmental protection.
Highlights
Herbicides are a type of pesticides used to target weeds and other unwanted plants
The pH of zero point of charge (pHzpc) is of fundamental importance in surface science applied to environmental rehabilitation, since it allows to determine the ability of a substrate to retain the molecules of interest
Process kinetics were satisfactorily described by the pseudo-second order (PSO) model for sepiolite, cork and pine bark
Summary
Herbicides are a type of pesticides used to target weeds and other unwanted plants They are considered emerging contaminants that have become a threat to water supply network. Atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) is a recalcitrant compound and an organonitrogen herbicide extensively used to control broadleaf and grass weeds [3] This herbicide does not tend to bioaccumulate, but its permanence in the environment and mobility in some soils can lead to surface and groundwater contamination [4]. Atrazine is commonly found in drinking water at levels exceeding 0.1 μg/L [3,4,5,6] as a result of its massive use in agriculture It is registered in more than 70 countries, making it the most commonly detected pesticide in surface water in the United States and frequently detected in groundwater as well [7]. Its use has been banned among the European countries since 2003, due its potential threat to human health, its endocrine-disrupting nature and embryotoxic and embryolethal functions [3,4]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
