Nanotechnology for Water Remediation
01 Jan 2019-pp 195-211
TL;DR: In this paper, the authors tried to incorporate an overview of recent advances in nanotechnologies for water and wastewater treatment and understand various advantages, limitations, and future direction, and their mode of action towards waste water remediation.
Abstract: Scarcity of fresh drinkable water has escalated to be the one of the major global problem. Traditional wastewater treatment technologies are not adequate enough to produce safe water due to increasing demand of water coupled with stringent health guidelines and emerging contaminants. On that note, the advent of nanotechnology has given immense scope and opportunities for the removal of heavy metals, microorganisms and organic pollutants from wastewater and has emerged to be a very dynamic branch in the utilization of nanotechnology due to their unique physiochemical and biological properties compared to their bulk. Exploiting these properties of high specific surface area and surface reactivity have resulted in the excessive use and study of nanoparticles in wastewater remediation. The use of various nanomaterials, including carbon based nanomaterial, metal and metal oxides nanoparticles as were focused on, and their mode of action towards waste water remediation were discussed. Herein we tried to incorporate an overview of recent advances in nanotechnologies for water and wastewater treatment and understand various advantages, limitations and future direction.
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TL;DR: In this article, the authors discuss some of the most recent and relevant findings related to the release of heavy metals, the possible risks for the environment and human health, the materials and technologies available for their removal.
Abstract: Water pollution is one of the global challenges that society must address in the 21st century aiming to improve water quality and reduce human and ecosystem health impacts. Industrialization, climate change, and expansion of urban areas produce a variety of water pollutants. In this work, we discuss some of the most recent and relevant findings related to the release of heavy metals, the possible risks for the environment and human health, the materials and technologies available for their removal. Anthropogenic activities are identified as the main source of the increasing amounts of heavy metals found in aquatic environments. Some of the health hazards derived from repeated exposure to traces of heavy metals, including lead, cadmium, mercury, and arsenic, are outlined. We also give some perspectives about several techniques used to detect heavy metals, as well as about the factors that could affect the contaminant removal. The advantages and drawbacks of conventional and non-conventional heavy metal removal methods are critically discussed, given particular attention to those related to adsorption, nanostructured materials and plant-mediated remediation. Some of the commercial products currently used to eliminate heavy metals from water are also listed. Finally, we point out some the requirements and opportunities linked to developing efficient methods for heavy metal removal, such as the ones that exploit nanotechnologies.
294 citations
TL;DR: In this paper, the preparation of chitosan-carbon nanotube supported palladium catalyst and the results of characterization studies by FTIR, XRD, TGA and SEM-EDX were reported.
67 citations
TL;DR: In this article, a mycosynthesis of ferromagnetic, monodispersed, spherical, crystalline iron oxide nanoparticles (IO-NPs) of 7305 ± 1547 nm were biofabricated using manglicolous fungi Aspergillus tubingensis (STSP 25) isolated from rhizospheric sediment samples of Avicennia officinalis which was sustainably used for the removal of heavy metals from the aqueous matrix.
Abstract: In our study, novel mycosynthesis of ferromagnetic, monodispersed, spherical, crystalline iron oxide nanoparticles (IO-NPs) of 7305 ± 1547 nm were biofabricated using manglicolous fungi Aspergillus tubingensis (STSP 25) isolated from rhizospheric sediment samples of Avicennia officinalis which was sustainably utilised for the removal of Pb (II), Ni (II), Cu (II), and Zn (II) from wastewater The elemental and XRD characterisation had shown Fe2O3 (hematite) nature of the IO-NPs which were aqua stable due to deposition of extracellular fungal bio molecules onto them Initial batch adsorption studies revealed that at pH 6 in 313 K temp, 1 g/L of IO-NPs could able to remove >90 % of heavy metals from the aqueous matrix This was further confirmed through muti-factor chemometric approach which involved RSM and ANN module RSM and ANN analysis inferred that 980037 % of Pb (II), 964502 % of Ni (II), 921984 % of Cu (II), and 939913 % of Zn (II) ions were adsorbed from 966 mg/L of heavy metals on 1 g/L concentration of IO-NPs in 30825 K temperature at pH 6 Adsorptive dynamics indicated the process of adsorption was kinetically spontaneous and thermodynamically it followed endothermic reaction, where metallic ions got chemisorbed on the monolayer interface of IO-NPs The overall process followed the Langmuir isotherm model and Pseudo-second order kinetics The Adsorbing potentiality of IO-NPs for Pb (II), Ni (II), Cu (II), and Zn (II) was found to be 9206 mg/g, 9666 mg/g, 8335 mg/g and 9106 mg/g respectively Reusability study showed IO-NPs had high regeneration capability till five adsorption/desorption cycle
47 citations
TL;DR: In this paper, green emerging technologies involving lignocellulosic waste to synthesize the NPs from the waste streams and the role of potential microorganisms such as microalgae, fungi, yeast, bacteria for the synthesis of NPs have been discussed.
17 citations
TL;DR: In this paper, a novel method employing atmospheric pressure discharge plasma has been developed to reduce supported Ag nanoparticles (Ag NPs) and deposited on TiO2 powder without the use of any environmentally and biologically hazardous reducing chemicals.
Abstract: A novel method employing atmospheric pressure discharge plasma has been developed to reduce supported Ag nanoparticles (Ag NPs) and deposited on TiO2 powder without the use of any environmentally and biologically hazardous reducing chemicals. Ag/TiO2 nanocomposite was prepared by the atmospheric direct current plasma in water solution. Trisodium citrate and CMC was used as a capping agent for Ag nanoparticles. The nanocomposites were characterized using UV–Vis spectroscopy, X-ray diffraction, scanning electron microscopy. The results showed that Ag NPs with an average diameter of 20–35.5 nm were uniformly distributed on the powders surface. The presence of nanosilver particles in TiO2 matrix is clearly visible. The bandgap of TiO2/Ag was confirmed (2.65–2.85 eV) through UV–vis DRS, which was lower than TiO2 (3.8 eV). The photocatalytic effect was conducted by methylene blue degradation test. The photocatalytic activity of a series of 2 wt. % Ag/TiO2 composites was evaluated in the degradation of MB (used as a model pollutant) in aqueous solution under solar light. The 2.0 mol % of Ag-doped TiO2 shows 96% degradation of methylene blue (MB) within 50 min under visible light irradiation and exhibit highest photocatalytic performance.
12 citations
Cites background from "Nanotechnology for Water Remediatio..."
...The advanced oxidation processes (AOPs) involving heterogeneous semiconductor photocatalysts have attracted enormous attention owing to their compatibility as a pollution mediator (Nahirniak at. al. 2018; Amin et al. 2014; Saikia et al. 2019)....
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References
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TL;DR: Film and powders of TiO2-x Nx have revealed an improvement over titanium dioxide (TiO2) under visible light in optical absorption and photocatalytic activity such as photodegradations of methylene blue and gaseous acetaldehyde and hydrophilicity of the film surface.
Abstract: To use solar irradiation or interior lighting efficiently, we sought a photocatalyst with high reactivity under visible light. Films and powders of TiO 2- x N x have revealed an improvement over titanium dioxide (TiO 2 ) under visible light (wavelength 2 has proven to be indispensable for band-gap narrowing and photocatalytic activity, as assessed by first-principles calculations and x-ray photoemission spectroscopy.
11,402 citations
TL;DR: The field of photocatalysis can be traced back more than 80 years to early observations of the chalking of titania-based paints and to studies of the darkening of metal oxides in contact with organic compounds in sunlight as discussed by the authors.
5,729 citations
TL;DR: The results indicate that the bactericidal properties of the nanoparticles are size dependent, since the only nanoparticles that present a direct interaction with the bacteria preferentially have a diameter of approximately 1-10 nm.
Abstract: Nanotechnology is expected to open new avenues to fight and prevent disease using atomic scale tailoring of materials. Among the most promising nanomaterials with antibacterial properties are metallic nanoparticles, which exhibit increased chemical activity due to their large surface to volume ratios and crystallographic surface structure. The study of bactericidal nanomaterials is particularly timely considering the recent increase of new resistant strains of bacteria to the most potent antibiotics. This has promoted research in the well known activity of silver ions and silver-based compounds, including silver nanoparticles. The present work studies the effect of silver nanoparticles in the range of 1-100 nm on Gram-negative bacteria using high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM). Our results indicate that the bactericidal properties of the nanoparticles are size dependent, since the only nanoparticles that present a direct interaction with the bacteria preferentially have a diameter of approximately 1-10 nm.
5,609 citations
TL;DR: The results suggest that Ag nanoparticles can be used as effective growth inhibitors in various microorganisms, making them applicable to diverse medical devices and antimicrobial control systems.
4,319 citations
TL;DR: For the first time, a multi-variables optimization approach is described to determine the optimum operation parameters so as to enhance process performance and photooxidation efficiency in the photocatalytic water treatment process.
4,293 citations