Download or read book Reactivity and Lifetime of Nano scale Zero valent Iron for Groundwater Dense Non aqueous Phase Liquid Remediation written by Yueqiang Liu and published by . This book was released on 2006 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nanoscale Zerovalent Iron Particles for Environmental Restoration written by Tanapon Phenrat and published by Springer. This book was released on 2019-01-31 with total page 611 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first complete edited volume devoted to providing comprehensive and state-of-the art descriptions of science principles and pilot- and field-scaled engineering applications of nanoscale zerovalent iron particles (NZVI) for soil and groundwater remediation. Although several books on environmental nanotechnology contain chapters of NZVI for environmental remediation (Wiesner and Bottero (2007); Geiger and Carvalho-Knighton (2009); Diallo et al. (2009); Ram et al. (2011)), none of them include a comprehensive treatment of the fundamental and applied aspects of NZVI applications. Most devote a chapter or two discussing a contemporary aspect of NZVI. In addition, environmental nanotechnology has a broad audience including environmental engineers and scientists, geochemists, material scientists, physicists, chemists, biologists, ecologists and toxicologists. None of the current books contain enough background material for such multidisciplinary readers, making it difficult for a graduate student or even an experienced researcher or environmental remediation practitioner new to nanotechnology to catch up with the massive, undigested literature. This prohibits the reader from gaining a complete understanding of NZVI science and technology. In this volume, the sixteen chapters are based on more than two decades of laboratory research and development and field-scaled demonstrations of NZVI implementation. The authors of each chapter are leading researchers and/or practitioners in NZVI technology. This book aims to be an important resource for all levels of audiences, i.e. graduate students, experienced environmental and nanotechnology researchers, and practitioners evaluating environmental remediation, as it is designed to involve everything from basic to advanced concepts.
Download or read book Cost and Performance Report Nanoscale Zero valent Iron Technologies for Source Remediation written by Arun R. Gavaskar and published by . This book was released on 2005 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Iron Nanomaterials for Water and Soil Treatment written by Marta I. Litter and published by CRC Press. This book was released on 2018-09-03 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nanotechnology has a great potential for providing efficient, cost-effective, and environmentally acceptable solutions to face the increasing requirements on quality and quantity of fresh water for industrial, agricultural, or human use. Iron nanomaterials, either zerovalent iron (nZVI) or iron oxides (nFeOx), present key physicochemical properties that make them particularly attractive as contaminant removal agents for water and soil cleaning. The large surface area of these nanoparticles imparts high sorption capacity to them, along with the ability to be functionalized for the enhancement of their affinity and selectivity. However, one of the most important properties is the outstanding capacity to act as redox-active materials, transforming the pollutants to less noxious chemical species by either oxidation or reduction, such as reduction of Cr(VI) to Cr(III) and dehalogenation of hydrocarbons. This book focuses on the methods of preparation of iron nanomaterials that can carry out contaminant removal processes and the use of these nanoparticles for cleaning waters and soils. It carefully explains the different aspects of the synthesis and characterization of iron nanoparticles and methods to evaluate their ability to remove contaminants, along with practical deployment. It overviews the advantages and disadvantages of using iron-based nanomaterials and presents a vision for the future of this nanotechnology. While this is an easy-to-understand book for beginners, it provides the latest updates to experts of this field. It also opens a multidisciplinary scope for engineers, scientists, and undergraduate and postgraduate students. Although there are a number of books published on the subject of nanomaterials, not too many of them are especially devoted to iron materials, which are rather of low cost, are nontoxic, and can be prepared easily and envisaged to be used in a large variety of applications. The literature has scarce reviews on preparation of iron nanoparticles from natural sources and lacks emphasis on the different processes, such as adsorption, redox pathways, and ionic exchange, taking place in the removal of different pollutants. Reports and mechanisms on soil treatment are not commonly found in the literature. This book opens a multidisciplinary scope for engineers and scientists and also for undergraduate or postgraduate students.
Download or read book Effect of Groundwater Biogeochemistry on Zero Valent Iron Nanoparticles written by Sai Rajasekar Chandrasekar Rajajayavel and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Accidental spills and past improper disposal practices of chlorinated solvents have led to widespread soil and groundwater contamination. Drinking water standards for trichloroethylene (TCE) and many other chlorinated organic contaminants are in the range of 5 μg/L and these compounds have received extensive regulatory attention because these compounds are often carcinogenic and neurotoxic. Direct injection of reactive nanoscale zerovalent iron particles (NZVI) is considered to be a promising approach for remediation of chlorinated compounds. NZVI is a strong reducing agent that can effectively transform TCE and other chlorinated organic compounds to non-toxic end products. The objective of the research was to assess various biogeochemical conditions on the reactivity of iron nanoparticles in particular sulfidation of NZVI for remediation of TCE. In addition, the feasibility of coupled NZVI-based remediation and bioremediation using polymer-coated bimetallic NZVI and a dechlorinating mixed culture consortia (KB-1) was investigated. We demonstrated that the extent of sulfidation of NZVI enhances the rate of dechlorination of TCE compared to non-sulfidated NZVI, and this enhancement depends on the Fe/S molar ratio of the sulfidated NZVI particles. Batch experiments where TCE was reacted with NZVI sulfidated to different extents (Fe/S molar ratios 0.62 to 66) showed that the surface-area normalized first-order TCE degradation rate constant increased 40 fold compared to non-sulfidated NZVI. FX-ray photoelectron spectroscopy analyses showed formation of a surface layer of FeS and FeS2. This indicates sulfide ions reacted with NZVI iron sulfide on surface of S-NZVI. We propose that more electrons are preferentially conducted from sulfidated NZVI than from unamended NZVI to TCE, likely because of greater binding affinity of TCE on the reactive sites of the iron sulfide outer layer. Aging of sulfidated iron nanoparticles (S-NZVI) and their influence on rate of TCE dechlorination was compared to the aged non-sulfidated NZVI. Long-term experiments indicate that pseudo-first order H2 evolution rate constant for non-sulfidated NZVI was 0.092 ± 0.005 d-1 and was significantly higher than the S-NZVI (Fe/S=25) at 0.051 ± 0.005 h-1. This difference in hydrogen evolved corresponds to the amount of reactive Fe(0) consumed in the absence of TCE. To further support, the efficacy of long-term reactivity S-NZVI batch TCE degradation experiment with anaerobically aged S-NZVI (40 days) degraded significantly more TCE than the non-sulfidated NZVI. Bimetallic, palladium-doped iron nanoparticles (Pd-NZVI) are capable of rapid transformation of higher initial TCE concentration, and the ability to form rapid H2 (electron donor for bacteria) may facilitate TCE biodegradation. Dehalococcoides are the only species of bacteria that are capable of degrading TCE completely to ethene under anaerobic conditions. Therefore, we investigated the interaction of carboxymethyl cellulose (CMC) stabilized palladium (Pd-NZVI) on the dechlorinating mixed culture KB-1 for reductive dechlorination of 1, 2 dichloroethane (DCA). Results suggest that systems with CMC alone as a sole carbon source and electron donor were capable of degrading 1, 2-DCA, and methane formation. The microcosms with KB-1 and polymer coated Pd-NZVI degraded 1, 2-DCA at a significantly higher rate constant compared to KB-1 and CMC systems. In addition, methanogenesis by KB-1 showed no statistically significant difference in the methane formation rate constants between Pd-CMC-NZVI and CMC only systems.Overall, this research demonstrates NZVI reactivity towards TCE and its longevity (efficacy) under anaerobic conditions can be enhanced with sulfidation. In addition, this research also shows that CMC stabilized bimetallic NZVI, is not inhibitory to Dehalococcoides spp. and could promote complete bioremediation." --
Download or read book Nanotechnologies for Environmental Remediation written by Giusy Lofrano and published by Springer. This book was released on 2017-03-02 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book discussing the principles of green chemistry and green engineering an international team of investigators present significant recent developments in applying nanoscience, nanoengineering, and nanotechnology to the area of environmental remediation. The opening chapters introduce candidate nanomaterials, properties, mechanisms that enable the applications, the advantages and limitations compared to existing processes and commercial research requirements. It then explores the detection and application of nanomaterials in photocatalytic processes and as adsorbents, and also covers the effect of nanoparticles in the activated sludge process. Later chapters focus on the effects of nanoparticles on crops, the risks associated with the presence of nanoparticles in the environment, and lastly the environmental effects of nanoscale zero-valent iron (nZVI) on land remediation. This timely, multi-author contributed volume is aimed at students, technicians, and academics interested in the role, risks and benefits of nanotechnology in modern environmental contexts.
Download or read book Optimization of Nanoscale Zero valent Iron for the Remediation of Groundwater Contaminants written by Andrew W.E. McPherson and published by . This book was released on 2012 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Groundwater Engineering written by Rajandrea Sethi and published by Springer. This book was released on 2019-07-03 with total page 439 pages. Available in PDF, EPUB and Kindle. Book excerpt: This textbook employs a technical and quantitative approach to explain subsurface hydrology and hydrogeology, and to offer a comprehensive overview of groundwater-related topics such as flow in porous media, aquifer characterization, contaminant description and transport, risk assessment, and groundwater remediation. It describes the characterization of subsurface flow of pristine and polluted water and provides readers with easily applicable tools for the design of water supply systems, drinking-water source protection, and remediation interventions. Specific applications range from groundwater exploitation as a drinking water supply to the remediation of contaminated aquifers, from the definition and safeguarding of drinking-water sources to the assessment of human health risks in connection with groundwater contamination events. The book represents an ideal learning resource for upper-undergraduate and graduate students of civil engineering, environmental engineering, and geology, as well as practitioners in the fields of water resource management and environmental protection who are interested in groundwater engineering and technical hydrogeology.
Download or read book Treatment of Chlorinated Hydrocarbon Contaminated Groundwater with Injectable Nanoscale Bimetallic Particles written by and published by . This book was released on 2009 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: ARCADIS conducted a laboratory research project for the Environmental Security Technology Certification Program (ESTCP) that evaluated the reductive dechlorination of trichloroethene (TCE) by multiple types of nanoscale zero valent iron (nZVI) particles obtained from multiple manufacturers. The manufacturing methods used to produce the nZVI particles utilized during this research result in particles that fall into two structural categories that ARCADIS defined during this research including particles with amorphous atomic structures and those with crystalline atomic structures. ARCADIS has shown that structural differences in iron particles can lead to profoundly different properties during the utilization of the nZVI for reductive dechlorination of TCE. Different phases of the laboratory program focused on the, reactivity, longevity, injectability and potential for treatment of dense, nonaqueous phase liquid (DNAPL) for multiple manufactured types of nZVI with both amorphous and crystalline structures. Over the multiyear laboratory research program, several of the multiple venders of nZVI contributing materials were engaged in product development/improvement efforts leading to nZVI with enhanced performance characteristics. Due to the relatively high cost of nZVI as a consumable remediation reagent, this laboratory program was aimed at investigating the factors that combine to influent return on investment including rate of reactivity, longevity under aquifer conditions, and potential to effectively treat DNAPL.
Download or read book Investigations on Mobility of Carbon Colloid Supported Nanoscale Zero valent Iron nZVI for Groundwater Remediation written by and published by . This book was released on 2015 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: Injection of nanoscale zero-valent iron (nZVI) is an innovative technology for in situ installation of a permeable reactive barrier in the subsurface. Zerovalent iron (ZVI) is highly reactive with chlorinated hydrocarbons (CHCs) and renders them into less harmful substances. Application of nZVI instead of granular ZVI can increase rates of dechlorination of CHCs by orders of magnitude, due to its higher surface area. This approach is still difficult to apply due to fast agglomeration and sedimentation of colloidal suspensions of nZVI, which leads to very short transport distances. To overcome this issue of limited mobility, polyanionic stabilisers are added to increase surface charge and stability of suspensions. In field experiments maximum transport distances of a few metres were achieved. A new approach, which is investigated in this thesis, is enhanced mobility of nZVI by a more mobile carrier colloid. The investigated composite material consists of activated carbon, which is loaded with nZVI. In this cumulative thesis, transport characteristics of carbon-colloid supported nZVI (c-nZVI) are investigated. Investigations started with column experiments in 40 cm columns filled with various porous media to investigate on physicochemical influences on transport characteristics. The experimental setup was enlarged to a transport experiment in a 1.2-m-sized two-dimensional aquifer tank experiment, which was filled with granular porous media. Further, a field experiment was performed in a natural aquifer system with a targeted transport distance of 5.3 m. Parallel to these investigations, alternative methods for transport observations were investigated by using noninvasive tomographic methods. Experiments using synchrotron radiation and magnetic resonance (MRI) were performed to investigate in situ transport characteristics in a non-destructive way. Results from column experiments show potentially high mobility under environmental relevant conditions. Addition of mono-and bivalent salts, e.g. more than 0.5 mM/L CaCl2, might decrease mobility. Changes in pH to values below 6 can inhibit mobility at all. Measurements of colloid size show changes in the mean particle size by a factor of ten. Measurements of zeta potential revealed an increase of -62 mV to -82 mV. Results from the 2D-aquifer test system suggest strong particle deposition in the first centimetres and only weak straining in the further travel path and no gravitational influence on particle transport. Straining at the beginning of the travel path in the porous medium was observed with tomographic investigations of transport. MRI experiments revealed similar results to the previous experiments, and observations using synchrotron radiation suggest straining of colloids at pore throats. The potential for high transport distances, which was suggested from laboratory experiments, was confirmed in the field experiment, where the transport distance of 5.3 m was reached by at least 10% of injected nZVI. Altogether, transport distances of the investigated carbon-colloid supported nZVI are higher than published results of traditional nZVI
Download or read book Nanofer Zero Valent Iron Nanoparticles written by Mahmoud Eglal and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transport Reactivity and Fate of Polyelectrolyte Modified Zero Valent Iron Nanoparticles Used for Groundwater Remediation in Heterogeneous Porous Media written by Hye-Jin Kim and published by . This book was released on 2009 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Alternatives for Managing the Nation s Complex Contaminated Groundwater Sites written by National Research Council and published by National Academies Press. This book was released on 2013-02-27 with total page 423 pages. Available in PDF, EPUB and Kindle. Book excerpt: Across the United States, thousands of hazardous waste sites are contaminated with chemicals that prevent the underlying groundwater from meeting drinking water standards. These include Superfund sites and other facilities that handle and dispose of hazardous waste, active and inactive dry cleaners, and leaking underground storage tanks; many are at federal facilities such as military installations. While many sites have been closed over the past 30 years through cleanup programs run by the U.S. Department of Defense, the U.S. EPA, and other state and federal agencies, the remaining caseload is much more difficult to address because the nature of the contamination and subsurface conditions make it difficult to achieve drinking water standards in the affected groundwater. Alternatives for Managing the Nation's Complex Contaminated Groundwater Sites estimates that at least 126,000 sites across the U.S. still have contaminated groundwater, and their closure is expected to cost at least $110 billion to $127 billion. About 10 percent of these sites are considered "complex," meaning restoration is unlikely to be achieved in the next 50 to 100 years due to technological limitations. At sites where contaminant concentrations have plateaued at levels above cleanup goals despite active efforts, the report recommends evaluating whether the sites should transition to long-term management, where risks would be monitored and harmful exposures prevented, but at reduced costs.
Download or read book Environmental Application and Implication of Nanoscale Zerovalent Iron written by Qiliang 'Luke' Wang and published by LAP Lambert Academic Publishing. This book was released on 2015-01-06 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book, the environmental application and implication of nanoscale zerovlanet iron (NZVI) are studied. Reduction and removal of Bromate and TCE DNAPL using NZVI were evaluated for drinking water treatment and groundwater remediation. A visualization technique for TCE DNAPL removal using reactive NZVI and bimetallic nanoparticles was conducted using a glass micromodel with a view toward improved contaminant displacement. Inert/pseudo-inert gases, including argon, nitrogen, and carbon dioxide, were utilized to stabilize synthesized NZVI after lyophilization to prevent self-ignition. In addition, the aging effect was investigated for these stabilized NZVI both in humid and dry conditions. A new and simple method was proposed for encapsulating NZVI using poly (vinyl pyrrolidone) (PVP) nanofibrous membranes by an electrospinning technology to maintain catalytic activity. At last, mobilization and deposition of NZVI in a porous medium were observed using a water-saturated glass micromodel; a high-resolution microscope was utilized to visualize the transport phenomena of microscopic aggregations of NZVI inside the micromodel.
Download or read book Synthesis of Magnetite derived Zero Valent Nanoiron and Targeting of Zero Valent Iron for Application in Environmental Remediation written by Daniel Edward Fowler and published by . This book was released on 2010 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dense non-aqueous phase liquids (DNAPLs) form underground contamination zones that are vast and heterogeneous in their spatial distribution, making them both difficult and costly to remediate. The use of nanoscale zero valent iron (NZVI) as an in-situ agent is a good method for reducing contaminants to less toxic forms, but it is limited by cost, scalability, and hazardous synthetic routes. A new inexpensive and environmentally benign synthetic technique of making carbon-adsorbed NZVI from the reduction of iron oxide (magnetite) with carbon black was developed. Powder X-ray diffraction and scanning electron microscopy confirmed that charged polyelectrolytes were necessary to promote sufficiently intimate mixing of the reactants for production of NZVI. Transmission electron microscopy revealed iron particles on the order of 50 to 150 nm diameter. Delivery of nanoparticles to subterranean contamination zones was modeled by the transport of carbonyl iron powder suspended in anionic polymer solutions through sand columns. Iron particles modified with different anionic polymers were found to target dichlorobenzene-coated sand grains with different degrees of effectiveness. Trends in targeting correlated well with the surface energies of the polymer-modified iron surfaces, which were measured by the contact angle method. The experimental results indicate that NZVI can be produced in a new inexpensive, green manner and that the contaminant targeting properties of micron-sized iron particles can be effectively tailored using simple polymeric adsorbents.
Download or read book Nanotechnology for Environmental Remediation written by Sung Hee Joo and published by Springer Science & Business Media. This book was released on 2006-06-18 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Examines the suitability of nanoscale zero-valent iron (ZVI) for degradation of agrochemicals. This book identifies by-products produced from the ZVI-mediated degradation process of particular contaminants, and explains the reaction mechanism by which ZVI degrades a chosen contaminant.
Download or read book Transport of Nanoscale Zero Valent Iron in Heterogeneous Soils written by Md. Abdullah Asad and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Subsurface remediation using nanoscale zero valent iron (nZVI) is a promising in-situ technology that can convert groundwater contaminants into non-toxic compounds. Despite its promising characteristics, field scale implementation of nZVI technology has faced major challenges due to poor subsurface mobility and limited longevity, all leading to smaller nZVI travel distance. How far nZVI travels in the subsurface is an important parameter as it influences the amount of contaminants that could be reached and thereby remediated. This thesis examined various factors (viscosity, groundwater velocity, injection flux, soil heterogeneity, lag period) on nZVI travel distance through a numerical model and by performing a statistical analysis which revealed that viscosity has a statistically significant impact on nZVI travel distance while the impact of groundwater velocity and injection flux are statistically insignificant. The model also revealed that soil heterogeneity plays an important factor and that longer nZVI injection periods are better for nZVI deployment in the field.
