Author: Patrick Kyle Jones
Publisher:
ISBN:
Category : Carbon, Activated
Languages : en
Pages : 124

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Book Description

Author: William Michael Kolling
Publisher:
ISBN:
Category :
Languages : en
Pages : 864

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Book Description

Author: Carla De Las Casas
Publisher:
ISBN:
Category :
Languages : en
Pages : 430

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Book Description
Fenton-dependent recovery of carbon initially saturated with one of several chlorinated aliphatic contaminants was studied in batch and continuous-flow reactors. A specialty carbon, URV-MOD 1 (Calgon) was employed to minimize non-productive H2O2 demand - that which does not yield hydroxyl or superoxide radicals. Enhancement of PCE degradation kinetics by ferric iron addition is limited by iron solubility, even at relatively low pH. Quinone addition increased the pseudo-first-order rate constant for PCE loss temporarily. Only copper addition sustainably enhanced the specific rate of PCE loss. For copper-to-iron molar ratios of 0.25 to 5, the pseudo-first-order rate constant for PCE transformation was increased by a factor of 3.5. It is apparent that the effect of copper addition on Fenton-dependent reaction rates is complex, and involves a shift in chemical mechanism, as indicated by the differing slopes in the Arrhenius plot (with and without copper).A mathematical model was developed to evaluate the effect of operational parameters ([Fe(III)]T:[H2O2]o ratio and pH) on degradation kinetics and optimize the PCE degradation process in homogeneous reaction mixtures. The model simulated experimental degradation of the organic target in a homogeneous Fenton-reaction system. The model requires further refinement to simulate Fenton's systems in which ions in solution (such as sulfate and chloride) play significant roles. In continuous-flow reactors, Fenton's reagents were cycled through spent GAC in columns to degrade one of seven chlorinated compounds tested. The contaminant with the weakest adsorption characteristics, methylene chloride, was 99% lost from the carbon surface during a 14-hour regeneration period. At the field site, the GAC was saturated with gases containing TCE and PCE from a soil vapor extraction (SVE) system. In the field, up to 95% of the sorbed TCE was removed from GAC during regeneration periods of 50-60 hours. Recovery of PCE-loaded GAC was significantly slower. Column experiments show that there is minimal loss of carbon adsorption capacity during Fenton treatment and that the rate of GAC regeneration is compound specific. Scoping-level cost estimates indicated that field use of Fenton regeneration is not cost effective without optimization and/or iron surface amendments, except in the case of the most soluble VOCs.

Author: Francois Beguin
Publisher: CRC Press
ISBN: 1420055402
Category : Science
Languages : en
Pages : 532

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Book Description
As carbons are widely used in energy storage and conversion systems, there is a rapidly growing need for an updated book that describes their physical, chemical, and electrochemical properties. Edited by those responsible for initiating the most progressive conference on Carbon for Energy Storage and Environment Protection (CESEP), this book undoub

Author: Robert G. Arnold
Publisher:
ISBN:
Category : Carbon
Languages : en
Pages : 143

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Book Description
Fenton-dependent recovery o fcarbon initially saturated with one of several chlorinated aliphatic contaminants was studied in batch and continuous-flow reactors. A specialty carbon, URV-MOD 1 (Calgon) was employed to minimize non-productive H2O2 demand - that which does not yield hydroxyl or superoxide radicals. Because the reductive reaction of Fe(III) to Fe(II) limits the overall rate of radical generation via Fenton's mechanism, it was hypothesized that steps designed to increase the rate of ferrous iron generation would accelerate Fenton-dependent contaminant destruction, enhancing carbon recovery kinetics. Homogeneous-phase experiments were designed to establish the effects on PCE destruction kinetics of total iron concentration and additions of NH2OH, various quinones or copper to the Fenton mixtures.

Author: Louis Hemphill
Publisher:
ISBN:
Category : Carbon, Activated
Languages : en
Pages : 120

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Book Description

Author: J. Haberman
Publisher:
ISBN:
Category :
Languages : en
Pages : 65

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Book Description
The TNT adsorption/solvent desorption cycling of activated carbon (FS300) has been studied as a function of various pretreatments. The preferential plugging of pores by the pretreatments did not enhance the regenerative property of the FS300. In conjunction with water adsorption/ desorption isotherms, the characteristics of a carbon with an improved cycling property has been elucidated. The improved property is due to a shift to larger pore volume and a larger ratio of pore opening to pore body diameters. Chemical regeneration of an activated carbon containing irreversible adsorbed TNT has been shown to be unfeasible.

Author:
Publisher:
ISBN:
Category : Dissertations, Academic
Languages : en
Pages : 312

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Book Description
"Education, arts and social sciences, natural and technical sciences in the United States and Canada".

Author: Teresa J. Bandosz
Publisher: Academic Press
ISBN: 0123705363
Category : Science
Languages : en
Pages : 571

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Book Description
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

Author: Saad Khalil
Publisher:
ISBN: 9783668795488
Category :
Languages : en
Pages : 32

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Book Description
Document from the year 2018 in the subject Engineering - Chemical Engineering, The University of Malaya, language: English, abstract: Granular palm shell activated carbon (AC) was impregnated separately with monoethanolamine (MEA) and 2-amino-2-methyl-1-propanol (AMP) to improve its natural capacity and selectivity for carbon dioxide (CO2) adsorption. The total surface area, micropore volume, as well as the heterogeneity of the impregnated AC particles was considerably reduced due to impregnation. CO2 intake of impregnated 500 μm AC particles improved significantly and adsorptive capacity of 500 μm MEA-impregnated AC particles improved by 172 % and 44 % comparing to non-impregnated and AMP-impregnated AC particles respectively. Solid state amine stoichiometric results indicated that adsorption capacity of unhindered amine (MEA) is higher than that of hindered amine (AMP) by 50 % contrary to liquid amines standard stoichiometry. Exhausted AMPimpregnated beds were regenerated by sweeping at room temperature with stream of pure nitrogen (N2) flowing at 60 ml/min for 4 hours. Heating up to 75 °C was required to regenerate exhausted MEA-impregnated beds. Increasing feed gas flow rate has adverse effect on breakthrough time more than increasing bed operating temperature. Breakthrough time was utilized to evaluate the performance of the different adsorption beds.