Download or read book Photocatalytic Destruction of Halogenated Organic Compounds in Water with a New Photocatalyst written by Mabruka Hadidan and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Photocatalytic Destruction of Volatile Organic Compounds in Water written by Steven Oluić and published by . This book was released on 1991 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Photocatalysts in Advanced Oxidation Processes for Wastewater Treatment written by Elvis Fosso-Kankeu and published by John Wiley & Sons. This book was released on 2020-05-19 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photocatalysts in Advanced Oxidation Processes for Wastewater Treatment comprehensively covers a range of topics aiming to promote the implementation of photocatalysis at large scale through provision of facile and green methods for catalysts synthesis and elucidation of pollutants degradation mechanisms. This book is divided into two main parts namely “Synthesis of effective photocatalysts” (Part I) and “Mechanisms of the photocatalytic degradation of various pollutants” (Part II). The first part focuses on the exploration of various strategies to synthesize sustainable and effective photocatalysts. The second part of the book provides an insights into the photocatalytic degradation mechanisms and pathways under ultraviolet and visible light irradiation, as well as the challenges faced by this technology and its future prospects.
Download or read book The Photocatalytic Destruction of Volatile Organic Compounds in Water written by Steven Oluić and published by . This book was released on 1991 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Photodegradation of Water Pollutants written by Martin M. Halmann and published by CRC Press. This book was released on 1995-12-05 with total page 322 pages. Available in PDF, EPUB and Kindle. Book excerpt: Photodegradation of Water Pollutants, the only complete survey available of current photocatalytic methods for treating water pollutants, covers all aspects of light-stimulated detoxification. Ideal for researchers and students, this new book explains methods for pollution treatment that have proven more effective than conventional biodegradation. Photodegradation of Water Pollutants examines advanced oxidation processes that have been successful in treating the chemical substances produced by industrial effluents and intensive agriculture. These oxidation processes include irradiation with ultraviolet or visible light, the use of homogenous sensitizers, such as dyes, and the use of heterogeneous photocatalysts, such as dispersed semiconductors. In addition, Photodegradation of Water Pollutants addresses the naturally occurring self-cleaning of some pollutants in sunlit surface waters, as well as several alternative non-photochemical approaches to water treatment. Available treatment options are discussed for the main groups of water pollutants, including toxic inorganic ions (cyanides, heavy metals), hydrocarbon derivatives (oil spills, surfactants, pulp and paper wastes), halocarbons, organo-N, organo-P, and organo-S compounds. The text also contains a unique section on the economics of advanced oxidation pollution treatments.
Download or read book Photocatalysts for Organics Degradation written by Barbara Bonelli and published by MDPI. This book was released on 2020-06-23 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt: The quality of water is not only a technological and scientific issue, but a social and economic problem, in both developed and developing countries. Besides local regulations, which differ between regions and need constant upgrades, significant scientific developments are required in both the detection and removal of water contaminants. This Issue focuses on some recent advancements in the photocatalytic removal of organic pollutants, which is one of the aspects of the problem that involves the need of advanced catalysts and implies significant advancements in the field of materials science and chemical engineering.
Download or read book Photocatalysis and Water Purification written by Pierre Pichat and published by John Wiley & Sons. This book was released on 2013-03-26 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water is one of the essential resources on our planet. Therefore, fresh water and the recycling of waste-water are very important topics in various areas. Energy-saving green technologies are a demand in this area of research. Photocatalysis comprises a class of reactions which use a catalyst activated by light. These reactions include the decomposition of organic compounds into environmental friendly water and carbon dioxide, leading to interesting properties of surfaces covered with a photocatalyst: they protect e.g. against incrustation of fouling matter, they are self-cleaning, antibacterial and viricidal. Therefore, they are attractive candidates for environmental applications such as water purification and waste-water treatment. This book introduces scientists and engineers to the fundamentals of photocatalysis and enlightens the potentials of photocatalysis to increase water quality. Also, strategies to improve the photocatalytic efficacy are pointed out: synthesis of better photocatalysts, combination of photocatalysis with other technologies, and the proper design of photocatalytic reactors. Implementation of applications and a chapter on design approaches for photocatalytic reactors round off the book. 'Photocatalysis and Water Purification' is part of the series on Materials for Sustainable Energy and Development edited by Prof. G.Q. Max Lu. The series covers advances in materials science and innovation for renewable energy, clean use of fossil energy, and greenhouse gas mitigation and associated environmental technologies.
Download or read book Water Pollution and Remediation Photocatalysis written by Inamuddin and published by Springer Nature. This book was released on 2020-10-29 with total page 443 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the context of climate change and fossil fuel pollution, solar energy appears as a cheap and sustainable fuel for many environmental applications, yet the efficiency of techniques has to be improved. This book reviews recent methods and applications of photocatalysis for the treatment of wastewater containing bacteria, heavy metals, organic pollutants, dyes and tannery effluents. Basics of water pollution, polluted river ecosystems and membranes are also detailed.
Download or read book Photocatalytic Reaction Engineering written by Hugo de Lasa and published by Springer Science & Business Media. This book was released on 2005-05-05 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heterogeneous photocatalysis is a novel technique for water purification. Publications on photocatalysis span a relatively recent period of not more than 25 years. This is a technique that, according to our extensive experience on the development of laboratory scale and pilot plant units, has great promise to eliminate water and air pollutants. Photocatalysis offers much more than competitive techniques where pollutants are transferred from phases; photocatalysis can achieve complete mineralization of pollutants leaving non-toxic species such as CO2 and H2O and can be exploited at close to room temperature and ambient pressure.
Download or read book Photocatalytic Destruction of Vapor Phase Volatile Organic Compounds written by Rajiv Srivastava and published by . This book was released on 1996 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Photocatalytic Destruction of Chlorinated Solvents with Solar Energy written by and published by . This book was released on 1990 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sandia National Laboratories and the Solar Energy Research Institute are developing a photocatalytic process to destroy organic contaminants in water. Tests with common water pollutants are being conducted at Sandia's Solar Thermal Test Facility using a near commercial-scale single-axis tracking parabolic trough system with glass pipe mounted at its focus. Experiments at this scale provide verification of laboratory studies and allow examination of design and operation issues at a real-life scale. The catalyst, titanium dioxide (TiO2), is a harmless material found in paint, cosmetics and toothpaste. Experiments were conducted to determine the effect of key process parameters on destruction rates of two chlorinated organic compounds which are common water pollutants: trichloroethylene and trichloroethane. In this paper, we summarize the engineering-scale results of these experiments and analyses. 21 refs., 8 figs.
Download or read book Heterogeneous Photocatalytic Degradation of Organic Pollutants in Water Over Nanoscale Powdered Titanium Dioxide written by Khaled M. Mezughi and published by . This book was released on 2011 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organic contaminants from industrial and/or domestic effluents may be harmful to humans directly or indirectly by degrading the quality of the aquatic environment. Consequently these contaminants must be reduced to levels that are not harmful to humans and the environment before disposal. Chemical, physical and biological methods exist for the removal of these pollutants from effluents. Among the available chemical methods, heterogeneous photocatalytic oxidation has been found particularly effective in removing a large number of persistent organics in water. In this study, photocatalytic degradation was explored for the removal of reactive azo-dye (textile dye), triclocarban (disinfectant), clopyralid (herbicide) and three endocrine disrupting compounds (EDCs) (estrone, 17?-estradiol and 17?-ethinylestradiol) from synthetic effluents. The major factors affecting the photocatalytic processes including the initial concentration of the target compounds, the amount of catalyst, the light intensity, the type of catalyst, the electron acceptor, the irradiation time and the pH were studied. Other oxidation techniques including (O3, H2O2, UV) were also studied. Generally UV light is used in combination with titanium dioxide, as photocatalyst, to generate photoinduced charge separation leading to the creation of electron-hole pairs. The holes act as electron acceptors hence the oxidation of organics occur at these sites. These holes can also lead to the formation of hydroxyl radicals which are also effective oxidants capable of degrading the organics. The results obtained in this study indicated that photolysis (i.e. UV only) was found to have no effect on the degradation of reactive azo-dye (RO16). However, complete photocatalytic degradation of 20 mg/L (3.24?10-2 mM) RO16 was achieved in 20 minutes in the presence of 1g/L TiO2 Degussa P25 at pH 5.5. Comparison between various types of catalysts (i.e. Degussa P25, VP Aeroperl, Hombifine N) gave varied results but Degussa P25 was the most effective photocatalyst hence it was selected for this study. For RO16 the optimum catalyst concentration was 0.5 g/L TiO2 with initial concentration of 20 mg/L RO16. It was found that the disappearance of RO16 satisfactorily followed the pseudo first-order kinetics according to Langmuir-Hinshelwood (L-H) model. The rate constant was k= 0.0928 mol/min. Photodegradation of TCC was studied in 70%v acetonitrile: 30%v water solutions. UV light degraded TCC effectively and the reaction rates increased with decreasing initial concentration of TCC. UV/TiO2 gave unsatisfactory degradation of triclocarban (TCC) since only 36% were removed in 60 minutes with initial concentration of TCC 20 mg/L. The degradation of clopyralid and the EDCs was studied using three oxidation systems UV/TiO2, UV/H2O2 and O3. Complete degradation of clopyralid (3,6-DCP) was achieved with UV/TiO2 in about 90 minutes at an optimum catalyst concentration of 1g/L. Zero-order kinetics was found to describe the first stage of the photocatalytic reaction in the concentration range 0.078-0.521 mM. At pH 5 the rate constant was 2.09?10-6? 4.32?10-7 M.s-1.Complete degradation of all the three EDCs was achieved with UV/H2O2 in 60 minutes at catalyst concentration of (2.94?10-2 M). On the other hand complete degradation of the EDCs was achieved in just 2 minutes with ozonation. For high concentration EDCs, TiO2/UV gave low efficiency of degradation as compared with ozone and H2O2/UV. First-order kinetics was found to describe the photocatalytic reaction of the EDCs.
Download or read book Investigation into High Efficiency Visible Light Photocatalysts for Water Reduction and Oxidation written by David James Martin and published by Springer. This book was released on 2015-05-14 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes novel strategies for the rational design of several cutting-edge high-efficiency photocatalysts, for applications such as water photooxidation, reduction, and overall splitting using a Z-Scheme system. As such, it focuses on efficient strategies for reducing energy loss by controlling charge transfer and separation, including novel faceted forms of silver phosphate for water photooxidation at record high rates, surface-basic highly polymerised graphitic carbon nitride for extremely efficient hydrogen production, and the first example of overall water splitting using a graphitic carbon nitride-based Z-Scheme system. Photocatalytic water splitting using solar irradiation can potentially offer a zero-carbon renewable energy source, yielding hydrogen and oxygen as clean products. These two ‘solar’ products can be used directly in fuel cells or combustion to provide clean electricity or other energy. Alternatively they can be utilised as separate entities for feedstock-based reactions, and are considered to be the two cornerstones of hydrogenation and oxidation reactions, including the production of methanol as a safe/portable fuel, or conventional catalytic reactions such as Fischer-Tropsch synthesis and ethylene oxide production. The main driving force behind the investigation is the fact that no photocatalyst system has yet reported combined high efficiency, high stability, and cost effectiveness; though cheap and stable, most suffer from low efficiency.
Download or read book Nanophotocatalysis and Environmental Applications written by Inamuddin and published by Springer. This book was released on 2020-08-15 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book will be a guiding path to understand the photocatalytic process and mechanism for the deterioration of heavy metals, persistent organic pollutants and pathogens from wastewater. Environmental remediation is of crucial importance in the context of human sustainability in the present and future times. The unplanned anthropogenic activities and revolutionary industrialization end up in environmental contamination with noxious organic-inorganic and biogenic pollutants. The photocatalytic disinfection and detoxification is the only solution to preserve and restore the ecological balance. The main emphasis is to explore and enhance the photocatalytic potentials of solar active-materials.
Download or read book An Evaluation of the Technical Feasibility of Photocatalytic Oxidation and Phase Transfer Catalysis for Destruction of Contaminants from Water written by and published by . This book was released on 1996 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Present efforts have developed photocatalysts best suited for the destruction of hydrophobic and hydrophilic organic contaminants. Using solar Insolation with Pt-TlO2 supported on silica gel, the best supported photocatalyst identified in a systematic evaluation, can mineralize trichioroethylene (8 mg/l) completely in a short time of 1.3 minutes. The destruction rate using this supported catalyst is four times greater than that using the optimized slurry made with the best photocatalyst Identified, and sixteen times greater than using a slurry made with the best commercially available catalyst. Catalyst supports are successfully surface-modified to increase adsorption capacity and in turn the overall destruction rates. Using solar insolation or artificial light sources for the applications in both water and air phases, the fixed-bed processes utilizing the supported photocatalyst have successfully mineralized other compounds with a wide range of adsorbabilities and photoactivities. Present efforts also have developed an adsorbent regeneration strategy: using saturated steam followed by photocatalysis to regenerate the spent adsorbents, and to destroy the desorbed organic compounds in the steam or steam condensate. Limited efforts have been made to model photocatalysis and steam desorption. The technologies have been tested successfully in the field at Tyndall AFB, FL and K.I. Sawyer AFB, MI and at a water treatment plant in Wausau, WI.
Download or read book Heterogeneous Photocatalysis For The Treatment Of Contaminants Of Emerging Concern In Water written by Jose Ricardo Alvarez Corena and published by . This book was released on 2015 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The simultaneous degradation of five organic contaminants: 1,4 dioxane, n-nitrosodimethylamine, tris-2-chloroethyl phosphate, gemfibrozil, and 17[beta] estradiol, was investigated using a 1 L batch water-jacketed UV photoreactor utilizing titanium dioxide (TiO2) nanoparticles (Degussa P-25) as a photocatalyst. The primary objectives of this research were: (1) to experimentally assess the feasibility of heterogeneous photocatalysis as a promising alternative for the degradation of organic compounds in water; and (2) to model the chemical reactions by the application of two different approaches based on adsorption -- surface reactions (Langmuir-Hinshelwood) and its simplification to a first order rate reaction. These objectives were motivated by the lack of information regarding simultaneous degradation of organic compounds in different categories as found in real aqueous matrices, and generation of specific intermediates that could eventually represent a potential risk to the environment. Contaminants were chosen based on their occurrence in water sources, their representativeness of individual sub-categories, and their importance as part of the CCL3 as potential contaminants to be regulated. Contaminant degradation was evaluated over time, and the TiO2 concentration and solution pH were varied under constant UV irradiation, oxygen delivery rate, mixing gradient, and temperature. Specific accomplishments of this study were: (1) reaction kinetics data were obtained from the UV/TiO2 experiments and showed the potential that this UV/TiO2 process has for effectively removing different types of organic compounds from water; (2) a good fit was obtained between photocatalytic reaction kinetics models and the contaminant data using pseudo first-order and Langmuir-Hinshelwood (L-H) models; (3) results of the analytical methods developed in this study were validated by measurements performed by a certified laboratory; (4) the reaction kinetic parameters obtained in this study were normalized to electrical energy per order, reactor volume and surface area of the photocatalyst in order to provide rate constants with wider applicability for scale-up to more complex systems; and (5) degradation intermediates from the oxidation process and from interaction among compounds were identified and possible pathways for their formation suggested. This research has provided a better understanding of the photocatalytic process for the removal of organic contaminants from complex aqueous matrices.
Download or read book Photocatalytic Destruction of Volatile Organic Compounds from the Oil and Gas Industry written by Oluwatosin Tokode and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
