Download or read book Effects of Activated Carbon Characteristics on Organic Contaminant Removal written by Detlef R. U. Knappe and published by IWA Publishing. This book was released on 2004-01-01 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many water treatment plants need to remove objectionable trace organic compounds, and activated carbon adsorption is often the best available technology. Utilities face the challenge of having to choose from a large variety of activated carbons, and iodine number or BET surface area values are often utilized in the selection process. Although neither parameter correlates well with adsorption capacities, alternative activated carbon selection criteria based on fundamental adsorbent and adsorbate properties are lacking to date. The first objective of this research was to systematically evaluate the effects of activated carbon pore structure and surface chemistry on the adsorption of two common drinking water contaminants: the relatively polar fuel oxygenate methyl tertiary-butyl ether (MTBE) and the relatively nonpolar solvent trichloroethene (TCE). The second objective was to develop simple descriptors of activated carbon characteristics that facilitate the selection of suitable adsorbents for the removal of organic contaminants from drinking water.Originally published by AwwaRF for its subscribers in 2003 This publication can also be purchased and downloaded via Pay Per View on Water Intelligence Online - click on the Pay Per View icon below

Download or read book Effects of Activated Carbon Surface Chemistry and Pore Structure on the Adsorption of Trace Organic Contaminants from Aqueous Solution written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The principal objectives of this research were (1) to identify activated pore structure and surface chemistry characteristics that assure the effective removal of trace organic contaminants from aqueous solution, and (2) to develop a procedure to predict the adsorption capacity of activated carbons from fundamental adsorbent and adsorbate properties. To systematically evaluate pore structure and surface chemistry effects on the adsorption of organic micropollutants from aqueous solution, a matrix of activated carbon fibers (ACFs) with three activation levels and four surface chemistry levels was prepared and characterized. In addition, three commercially available granular activated carbons (GACs) were studied to verify whether correlations developed for the ACF matrix are valid for adsorbents that are typically used for water treatment. BET surface area, pore size distribution, elemental composition, point of zero charge and infrared spectroscopy data were obtained to characterize the adsorbents. The results showed that the ACF matrix prepared in this study permits a fairly independent evaluation of surface chemistry and pore structure effects on organic contaminant adsorption from aqueous solution. Methyl tertiary-butyl ether (MTBE), a relatively hydrophilic adsorbate, and trichloroethene (TCE), a relatively hydrophobic adsorbate, served as adsorbate probes. To evaluate the effects of natural organic matter (NOM) on MTBE and TCE adsorption capacities, isotherm experiments were conducted in ultrapure water and Sacramento-San Joaquin Delta water. With respect to surface chemistry, both single-solute isotherms and isotherms in the presence of NOM indicated that hydrophobic adsorbents more effectively removed TCE and MTBE from aqueous solution than hydrophilic adsorbents. Enhanced water adsorption on polar surface sites explained the poorer performance of the hydrophilic adsorbents. Based on the elemental composition of the low-ash carbons evaluated in this study, act.

Download or read book Activated Carbon Surfaces in Environmental Remediation written by Teresa J. Bandosz and published by Elsevier. This book was released on 2006-02-27 with total page 587 pages. Available in PDF, EPUB and Kindle. Book excerpt: Activated Carbon Surfaces in Environmental Remediation provides a comprehensive summary of the environmental applications of activated carbons. In order to understand the removal of contaminants and pollutants on activated carbons, the theoretical bases of adsorption phenomena are discussed. The effects of pore structure and surface chemistry are also addressed from both science and engineering perspectives. Each chapter provides examples of real applications with an emphasis on the role of the carbon surface in adsorption or reactive adsorption. The practical aspects addressed in this book cover the broad spectrum of applications from air and water cleaning and energy storage to warfare gas removal and biomedical applications. This book can serve as a handbook or reference book for graduate students, researchers and practitioners with an interest in filtration, water treatment, adsorbents and air cleaning, in addition to environmental policies and regulations. Addresses fundamental carbon science and how it relates to applications of carbon surfaces Describes the broad spectrum of activated carbon applications in environmental remediation Serves as a handbook or reference book for graduate students, researchers and practitioners in the field

Download or read book Adsorption of Organic and Emerging Pollutants on Carbon Materials in Aqueous Media Environmental Implications written by Jordi Lladó Valero and published by . This book was released on 2016 with total page 299 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the last two decades an increasing presence of organic substances such drugs, pesticides, etc. has been detected in water which may affect the health of the organisms and the environment. Some of these contaminants remain in the water after the usual treatment in sewage plants. This fact makes evident the need of introduction of the tertiary treatments that allow the complete elimination of these substances. This Doctoral Thesis researches for the elimination of different organic and emerging compounds present in water by means of the adsorption with new activated carbons. In particular, new carbon materials from different wastes, coal, synthetic materials, which have been produced and characterized, allow the adsorption of the organic compounds widely used in society. Different characteristics of the adsorbents (chemical composition, functional groups, texture, etc.) and of adsorbates (dimensions, hydrophobicity, pKa, functional groups, etc.) that influence on the adsorption process have been studied. Moreover, in this work, an analysis and kinetic model have been proposed. The analytic model allow, by chemometrics, enhancing the quantification of two or more organic compounds in solution by spectroscopy UV-vis. The kinetic model proposed provides a better comprehension and interpretation, as a better prediction of the different parameters on the adsorption process. In this sense, the following Thesis presents five works which have allowed a better comprehension of the adsorption process by means carbon materials from different origin. The first work, "highly microporous activated carbons from biocollagenic wastes as adsorbents or aromatic pollutants in water originating from industrial activities", about the texture and chemical composition of activated carbon from biocollagenic wastes which have been studied in order to observe how these parameters affect on the adsorption of aromatic monosubstitued compounds. Moreover, different variables as temperature and activating agent are studied in the process of manufacture activated carbons. The second work, "Removal of pharmaceutical and Iodinated Contrast Media (ICM) compounds on carbon xerogels and activated carbons. NOM and textural properties influences", shows the important role of pore size distribution in activated carbon which plays on the adsorption of different pharmaceuticals (salicylic acid, paracetamol, diclifenac, etc.) and iodinated contrast media (iohexol, iodixanol, iomeprol, etc) of different size. The influence of natural organic matter (NOM) in water is also studied in the adsorption of the all pollutants. The adsorption of paracetamol, phenol and salicylicacid in different coal-based activated carbon is showed in the contain of the work "Removal of pharmaceutical pollutants in water using coal-based activated carbons". In this work, the chemical characteristics on the surface of activated carbons are studied in order to observe the influence in the adsorption of different organic compounds; and also the influence of the pH water. The results showed an increase of adsorption of salicylates due to the presence of sulphur on the surface of the adsorbent. The fourth work; "Multicomponent adsorption on coal-based activated carbons on aqueous media: new cross-correlation analysis method", as a continuation of the previous work, shows a new chemometric technique that allows to analysis the binary and ternary solutions correctly by UV-vis spectroscopy. Moreover, the competitive effect between two or three molecules is studied on the adsorption process. In the last work, "Role of activated carbon properties in atrazine and paracetamol adsorption equilibrium and kinetics", a new kinetic model is proposed for the adsorption of paracetamol and atrazine using activated carbon from sewage sludge and two, commercial, activated carbons.

Download or read book Activated Carbon Adsorption written by Roop Chand Bansal and published by CRC Press. This book was released on 2005-05-24 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt: High surface area, a microporous structure, and a high degree of surface reactivity make activated carbons versatile adsorbents, particularly effective in the adsorption of organic and inorganic pollutants from aqueous solutions. Activated Carbon Adsorption introduces the parameters and mechanisms involved in the activated carbon adsorption

Download or read book Surface Properties Volume 95 written by Ilya Prigogine and published by Wiley-Interscience. This book was released on 1996-08-02 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of surfaces has experienced dramatic growth over the past decade. Now, the editors of the internationally celebrated series Advances in Chemical Physics have brought together in this self-contained, special topic volume contributions from leading researchers in the field treating some of the most crucial aspects of the experimental and theoretical study of surfaces. This work delves into such core issues as: * Kinetics and dynamics of hydrogen adsorption on silicon surfaces. * Potential energy surfaces of transition- metal-catalyzed chemical reactions. * High-resolution helium atom scattering as a proof of surface vibrations. * Ordering and phase transitions in adsorbed monolayers of diatomic molecules. * The influence of dimensionality on static and dynamic properties of a system. * New applications to fields as varied as catalysts and the passage of molecules through membranes. This valuable resource provides important insights into the current state of knowledge about surface properties. Prigogine and Rice's latest work will stimulate the imagination and motivate the exploration of other aspects of this fascinating subject.

Download or read book Activated Carbon for Water and Wastewater Treatment written by Ferhan Cecen and published by John Wiley & Sons. This book was released on 2011-09-19 with total page 409 pages. Available in PDF, EPUB and Kindle. Book excerpt: This monograph provides comprehensive coverage of technologies which integrate adsorption and biological processes in water and wastewater treatment. The authors provide both an introduction to the topic as well as a detailed discussion of theoretical and practical considerations. After a review of the basics involved in the chemistry, biology and technology of integrated adsorption and biological removal, they discuss the setup of pilot- and full-scale treatment facilities, covering powdered as well as granular activated carbon. They elucidate the factors that influence the successful operation of integrated systems. Their discussion on integrated systems expands from the effects of environmental to the removal of various pollutants, to regeneration of activated carbon, and to the analysis of such systems in mathematical terms. The authors conclude with a look at future needs for research and develoment. A truly valuable resource for environmental engineers, environmental and water chemists, as well as professionals working in water and wastewater treatment.

Download or read book Removal of Organic Contaminants from Drinking Water Using Techniques Other Than Granular Activated Carbon Alone written by and published by . This book was released on 1979 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mechanisms of Competitive Adsorption Between Trace Organic Contaminants and Natural Organic Matter on Activated Carbon written by Li Ding and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Activated carbon adsorption is widely used in water treatment for removal of various organic micropollutants; nonetheless, the presence of natural organic matter (NOM) in source water can reduce its efficiency for micropollutant removal. NOM has been shown to compete with target contaminant via different mechanisms: direct competition for available adsorption sites which reduces equilibrium capacity for target compounds, blocking of pore entrance which reduces diffusion rate of the target compounds, and covering of surface sites which may actually enhances diffusion rate of the target compounds. The objective of this dissertation study was to further elucidate the individual competitive effects, to investigate how pore sizes of adsorbents and molecular structure of competing compounds affect competition and to gain a comprehensive understanding of the competitive adsorption. Atrazine, a widely used herbicide in the United States, was used as the trace-level target contaminant and NOM from different source waters as well as NOM surrogates were used as the competing compounds. Powdered activated carbons (PACs) with different pore size distribution (PSD) were used. The PSD was found to have great influence on the pore blockage (PB) effect caused by NOM. The equilibrium capacity of the NOM used in this study was best correlated to the amount of pores of diameter 15-50 ©5, which was also inversely related to the magnitude of the pore blockage effect. Activated carbon that has more surface area in this pore size range had a smaller PB effect on atrazine adsorption kinetics at the same NOM loading. This finding indicated that mesopores are important in realizing adsorption capacity for trace compounds by alleviating the adverse PB effect. The site covering effect was confirmed with additional types of PACs and various competing compounds. More important, the correlation equation that describes the enhanced surface diffusion coefficient for atrazine as a function of the loading of the site-covering compounds was found to be independent of either the PAC type or the competing compound type. The key component was to quantify the competing compound as the equivalent background compound (EBC), which reflected the extent of active sites being covered. iii The site competing effect, the site covering effect and the pore blocking effect were evaluated for five NOM surrogates with different sizes. The smaller molecules were generally more effective in reducing the equilibrium capacity of the target compound. However, for molecules of similar molecular weight, elongated molecules tended to have more equilibrium effect than round molecules. From a kinetic perspective, the enhancement in diffusivity was within one order of magnitude for all five surrogates, while the extent of the PB effect was greatly relying on molecular size that large-sized surrogates caused a much stronger PB effect. Therefore, the overall kinetic effect was dependent on molecular size and the PB effect was usually dominant except for very small molecules. Consistent with the enhanced kinetics associated with pre-adsorbed site-covering competing compounds, atrazine preloading was found to also increase the diffusion coefficient of atrazine, and the extent of enhancement caused by atrazine was greater than that caused by competing compounds. Several explanations were proposed for the difference, which include the micropore filling hypothesis and the artifact associated with the EBC method that was used for site-covering loading quantification.

Download or read book Activated Carbon Surface Chemistry and Adsorption from Solution written by James S. Mattson and published by . This book was released on 1971 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Activated Carbon Surface Chemistry and Pore Structure on the Absorption of Methyl Tertiary Butyl Ether and Trichloroethene from Natural Water written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Activated carbon adsorption is the best available treatment technology for thecontrol of many objectionable trace organic compounds. Activated carbons are frequentlycharacterized by the iodine number and BET surface area, but these parameters do notcorrelate well with trace organic compound removal from natural water. Therefore, theobjective of this research was to develop activated carbon selection criteria that assure theeffective removal of trace organic contaminants from natural water and to base theselection criteria on the adsorbent's pore structure and surface chemistry. Tosystematically evaluate pore structure and surface chemistry effects, a matrix of activatedcarbon fibers (ACFs) with three activation levels and four surface chemistry levels wasstudied. To evaluate whether adsorption trends established for ACFs were also valid forgranular activated carbon (GAC), ACF results were compared with those obtained forthree commercially available GACs. Adsorption capacities were determined for naturalorganic matter (NOM), for relatively hydrophilic methyl tertiary-butyl ether (MTBE) andrelatively hydrophobic trichloroethene (TCE) in organic-free water, and for MTBE andTCE in the presence of NOM. NOM isotherms showed that DOC adsorption occurredprimarily in pores with diameters in the 11 to 500 Å range and that electrostaticinteractions between NOM and the carbon surface played a role in NOM adsorption. According to both single-solute isotherms and micropollutant isotherms in the presence of NOM, hydrophobic adsorbents more effectively removed TCE and MTBE thanhydrophilic adsorbents. Effective adsorbents for drinking water treatment shouldtherefore contain little oxygen and nitrogen whose presence increases the polarity of theadsorbent surface. Based on the elemental composition of the low-ash carbons evaluatedin this study, activated carbons should have oxygen and nitrogen contents that sum to nomore than 2 to 3 mmol/g to assure sufficient hydrophobicity. In a.

Download or read book Effect of Surface Groups on Adsorption of Pollutants written by Robert W. Coughlin and published by . This book was released on 1970 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Micropollutants and Challenges written by Afsane Chavoshani and published by Elsevier. This book was released on 2020-06-12 with total page 293 pages. Available in PDF, EPUB and Kindle. Book excerpt: Micropollutants and Challenges: Emerging in the Aquatic Environments and Treatment Processes systematically summarizes the characteristics, micropollutants types, production resources, occurrence in aqueous environments, health effects, methods of detection and treatments. Throughout each chapter, the following topics will be presented: (i) The quality and quantity evaluation of aquatic micro-pollutants, (ii) The need for innovative and affordable wastewater treatment technologies, and (iii) Combinations of different conventional and advanced technologies, including the biological and plant-based strategies that seem most promising. - Presents information on the micropollutants that threaten all living organisms, showing the importance and relevance of this topic - Assesses the effects of micropollutants on surface and groundwater - Provides solutions for the removal of micropollutants in conventional and advanced treatment processes and compares the efficiency of different processes

Download or read book Removal of Polar and Emerging Organic Contaminants by Alternative Adsorbents written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The removal of polar and ionizable organic contaminants from drinking water sources is a challenge for water utilities. Prescription and non-prescription drugs are present at detectable levels in many US surface waters, and conventional water treatment processes do not provide an effective barrier for many emerging contaminants. Therefore, effective treatment technologies are required to successfully remove these contaminants from drinking water. In this study the effectiveness of alternative adsorbents for the removal of MTBE was evaluated. Additionally, adsorbent, adsorbate, and water characteristics that affect ionizable organic contaminant adsorption were identified. In the first phase of this research, the MTBE removal effectiveness of activated carbon, a carbonaceous resin and a silicalite zeolite was compared. Isotherm and short bed adsorber tests were conducted in ultrapure water and river water to obtain parameters describing MTBE adsorption equilibria and kinetics and to quantify the effect of natural organic matter (NOM) on MTBE adsorption. Both the silicalite zeolite and the carbonaceous resin exhibited larger MTBE adsorption uptakes than the tested GAC. Results showed that GAC was the most cost-competitive adsorbent when considering adsorbent usage rate only; however, the useful life of an adsorber containing silicalite zeolite was predicted to be ~5-6 times longer than that of an equally sized adsorber containing GAC. Pilot column results also showed that NOM preloading did not impair the MTBE removal efficiency of the silicalite zeolite. Thus, it may be possible to regenerate spent silicalite with less energy-intensive methods than those required to regenerate GAC. One activated carbon, one carbonaceous resin, and two high-silica zeolites were studied to evaluate their effectiveness for the removal of an emerging pollutant of concern (EPOC) mixture from lake water. Adsorption isotherm experiments were performed with environmentally relevant concentrat.

Download or read book Desorption of Trace Contaminants From Activated Carbon Effect of Strongly Competing and Pore Blocking Background Organic Matter on Desorption Kinetics written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Emerging Carbon Based Nanocomposites for Environmental Applications written by Ajay Kumar Mishra and published by John Wiley & Sons. This book was released on 2020-09-29 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book is a comprehensive deep-dive into the developments and advancements of emerging carbon-based nanocomposites for wastewater applications. Science and technology development are tackling one of the world's most pressing concerns—water contamination and effective treatment. Carbon-based nanocomposites have emerged as one of the leading materials in this treatment push because of their properties and high ability for the catalytic degradation of contaminants from aqueous segments. The 10 chapters in this timely book cover the follows areas: Carbon-based nanocomposites for remediation of heavy metals and organic pollutants from wastewater Functional green carbon nanocomposites for heavy-metal treatment in water Green nanocomposites and applications in environmentally-friendly carbon nanomaterials Carbon-based nanocomposites as heterogeneous catalysts for organic reactions in environment-friendly solvents Carbon-based polymer nanocomposite applications Biochar-based adsorbents for the removal of organic pollutants from aqueous systems Carbon nanomaterial-based green nanocomposites The removal of trihalomethanes from water using nanofiltration membranes Nanocomposite materials as electrode materials in microbial fuel cells for the removal of water pollutants Plasmonic smart nanosensors for the determination of environmental pollutants.

Download or read book Organic Contaminant Removal in Lower Mississippi River Drinking Water by Granular Activated Carbon Adsorption written by Wayne E. Koffskey and published by . This book was released on 1981* with total page 631 pages. Available in PDF, EPUB and Kindle. Book excerpt: