Atmospherically stable NZVI (nanoscale zero-valent iron) particles were produced by modifying shell layers of Fe(H2) NZVI particles (RNIP-10DS) by using a controlled air contact method. Shell-modified NZVI particles were resistant to rapid aerial oxidation and were shown to have TCE degradation rate constants that were equivalent to 78% of those of pristine NZVI particles. Fe(H2) NZVI particles that were vigorously contacted with air (rapidly oxidized) showed a substantially compromised reactivity. Aging of shell-modified particles in water for one day resulted in a rate increase of 54%, implying that depassivation of the shell would play an important role in enhancing reactivity. Aging of shell-modified particles in air led to rate decreases by 14% and 46% in cases of one week and two months of aging, respectively. A series of instrumental analyses using transmission electron microscopy, X-ray diffractography, X-ray photoelectron spectroscopy, and X-ray absorption near-edge structure showed that the shells of modified NZVI particles primarily consisted of magnetite (Fe(3)O(4)). Analyses also implied that the new magnetite layer produced during shell modification was protective against shell passivation. Aging of shell-modified particles in water yielded another major mineral phase, goethite (alpha-FeOOH), whereas aging in air produced additional shell phases such as wustite (FeO), hematite (alpha-Fe(2)O(3)), and maghemite (gamma-Fe(2)O(3)).
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http://dx.doi.org/10.1021/es902772r | DOI Listing |
J Hazard Mater
January 2025
Department of Civil and Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea; Department of Environmental Engineering, Graduate School, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea. Electronic address:
The synthesis of coal bottom ash-induced zeolite (Si-Al material) has been widely reported; however, the selective recovery of the three main elements, viz., Si, Al, and Fe, from coal bottom ash for the synthesis of reactive adsorbents has not yet been reported. In this study, we separated the magnetic and non-magnetic fractions of coal bottom ash to selectively recover Fe and Si-Al for synthesizing nanoscale zero-valent iron@zeolite (NZVI@ZBA) composites with uniform formation of Fe(0) nanoparticles on the ZBA surface.
View Article and Find Full Text PDFEnviron Res
January 2025
School of Environment and Energy, Peking University Shenzhen Graduate School, University Town, Xili, Nanshan District, 518055, Shenzhen, China.
This work evaluated the effect of zero-valent iron (ZVI) particle size (150 μm-100 nm) on the performance of food waste anaerobic digestion (AD) under various acid stress conditions. The results indicated that ZVI significantly improved the AD performance, ensuring successful CH production even under high acid stress. However, the extent of this promoting effect was highly dependent on the particle size.
View Article and Find Full Text PDFiScience
December 2024
Enviromicrobiology, Ecotoxicology and Ecotechnology Research Laboratory (3E-MicroToxTech Lab), Department of Ecological Studies, University of Kalyani, Kalyani, Nadia 741235 West Bengal, India.
This study develops a graphene oxide-nano zerovalent iron (GO-nZVI) composite for the efficient removal of tetracycline and ciprofloxacin from water. The composite was synthesized using sugarcane bagasse as the matrix for graphene oxide (GO) and Sal leaf extract to reduce iron into nano zerovalent iron (nZVI). Microscopic analysis confirmed multiple GO layers with nZVI particles on their surface, while XRD and Raman spectroscopy verified the crystalline nature of the composite.
View Article and Find Full Text PDFJ Environ Manage
January 2025
Division of Environmental Science and Engineering (DESE), Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea; Division of Advanced Nuclear Engineering (DANE), Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea. Electronic address:
A geopolymer waste form has become a suitable approach for the immobilization of the volatile technetium (Tc) due to the low curing temperature (<60 °C). However, the low retention and the high mobility of the anionic technetium (TcO) remain challenging due to the charge repulsion stemming from the negative charges of the geopolymer surface and the anionic TcO. Herein, a geopolymer composite containing sulfidized nanoscale zerovalent iron (S-nZVI) was developed to reductively immobilize ReO (used as a non-radioactive surrogate for TcO).
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
Centre for Applied Research, Saveetha School of Engineering, Saveetha institute of Medical and Technical Sciences (SIMATS), Chennai, Tamil Nadu 602105, India.
Recent advances in nanotechnology, particularly those utilizing polymeric nanocomposites, have garnered significant attention for their effectiveness and biocompatibility in cancer diagnosis and treatment. In this study, a chitosan-okra mucilage polymeric nanocomposite doped with nano zero-valent iron (CS-OM-nZVI), synthesized using green chemistry principles, was evaluated for its anti-cancer activity against drug-resistant oral carcinoma cells (KBChR). The nanocomposite was created from chitosan, mucilage derived from okra biomass, and nano zerovalent iron particles synthesized through chemical reduction.
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