Download or read book Kinetic Modeling of Mercury Desorption and Adsorption on Fixed bed Sorbents written by Youngkil Lee and published by . This book was released on 1999 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling of Adsorption and Desorption of Mercury on Sorbents in a Fixed Bed Absorber written by Feng Guo and published by . This book was released on 1997 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling and Experimental Studies of Mercury Oxidation and Adsorption in a Fixed Bed and Entrained Flow Reactor written by and published by . This book was released on 2009 with total page 51 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents experimental and modeling mercury oxidation and adsorption data. Fixed-bed and single-particle models of mercury adsorption were developed. The experimental data were obtained with two reactors: a 300-W, methane-fired, tubular, quartz-lined reactor for studying homogeneous oxidation reactions and a fixed-bed reactor, also of quartz, for studying heterogeneous reactions. The latter was attached to the exit of the former to provide realistic combustion gases. The fixed-bed reactor contained one gram of coconut-shell carbon and remained at a temperature of 150°C. All methane, air, SO2, and halogen species were introduced through the burner to produce a radical pool representative of real combustion systems. A Tekran 2537A Analyzer coupled with a wet conditioning system provided speciated mercury concentrations. At 150°C and in the absence of HCl or HBr, the mercury uptake was about 20%. The addition of 50 ppm HCl caused complete capture of all elemental and oxidized mercury species. In the absence of halogens, SO2 increased the mercury adsorption efficiency to up to 30 percent. The extent of adsorption decreased with increasing SO2 concentration when halogens were present. Increasing the HCl concentration to 100 ppm lessened the effect of SO2. The fixed-bed model incorporates Langmuir adsorption kinetics and was developed to predict adsorption of elemental mercury and the effect of multiple flue gas components. This model neglects intraparticle diffusional resistances and is only applicable to pulverized carbon sorbents. It roughly describes experimental data from the literature. The current version includes the ability to account for competitive adsorption between mercury, SO2, and NO2. The single particle model simulates in-flight sorbent capture of elemental mercury. This model was developed to include Langmuir and Freundlich isotherms, rate equations, sorbent feed rate, and intraparticle diffusion. The Freundlich isotherm more accurately described in-flight mercury capture. Using these parameters, very little intraparticle diffusion was evident. Consistent with other data, smaller particles resulted in higher mercury uptake due to available surface area. Therefore, it is important to capture the particle size distribution in the model. At typical full-scale sorbent feed rates, the calculations underpredicted adsorption, suggesting that wall effects can account for as much as 50 percent of the removal, making it an important factor in entrained-mercury adsorption models.

Download or read book Modeling and Experimental Studies of Mercury Oxidation and Adsorption in a Fixed Bed Reactor written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents experimental and modeling mercury oxidation and adsorption data. Fixed-bed and single-particle models of mercury adsorption were developed. The experimental data were obtained with two reactors: a 300- W, methane-fired, tubular, quartz-lined reactor for studying homogeneous oxidation reactions and a fixed-bed reactor, also of quartz, for studying heterogeneous reactions. The latter was attached to the exit of the former to provide realistic combustion gases. The fixed-bed reactor contained one gram of coconut-shell carbon and remained at a temperature of 150oC. All methane, air, SO2, and halogen species were introduced through the burner to produce a radical pool representative of real combustion systems. A Tekran 2537A Analyzer coupled with a wet conditioning system provided speciated mercury concentrations. At 150°C and in the absence of HCl or HBr, the mercury uptake was about 20%. The addition of 50 ppm HCl caused complete capture of all elemental and oxidized mercury species. In the absence of halogens, SO2 increased the mercury adsorption efficiency to up to 30 percent. The extent of adsorption decreased with increasing SO2 concentration when halogens were present. Increasing the HCl concentration to 100 ppm lessened the effect of SO2. The fixed-bed model incorporates Langmuir adsorption kinetics and was developed to predict adsorption of elemental mercury and the effect of multiple flue gas components. This model neglects intraparticle diffusional resistances and is only applicable to pulverized carbon sorbents. It roughly describes experimental data from the literature. The current version includes the ability to account for competitive adsorption between mercury, SO2, and NO2. The single particle model simulates in-flight sorbent capture of elemental mercury. This model was developed to include Langmuir and Freundlich isotherms, rate equations, sorbent feed rate, and intraparticle diffusion. The Freundlich isotherm more accurately described in-flight mercury capture. Using these parameters, very little intraparticle diffusion was evident. Consistent with other data, smaller particles resulted in higher mercury uptake due to available surface area. Therefore, it is important to capture the particle size distribution in the model. At typical full-scale sorbent feed rates, the calculations underpredicted adsorption, suggesting that wall effects can account for as much as 50 percent of the removal, making it an important factor in entrained-mercury adsorption models.

Download or read book Mercury Adsorption and Desorption Kinetics written by Mark A. Bentley and published by . This book was released on 2012 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mercury emissions in the United States are regulated under the Clean Air Mercury Rule. Multiple mercury removal technologies have been investigated and at this time, activated carbon injection into flue gas has been considered to be an efficient and economically feasible method for the removal of elemental mercury. Also, chemical modifications to activated carbon have shown to increase its mercury sorption capacity and removal efficiency. In this study, adsorption of elemental mercury onto ferric chloride impregnated activated carbon was investigated. The results show that ferric chloride impregnated activated carbon has a higher mercury sorption capacity than raw activated carbon does. A chemisorption mechanism was proposed and confirmed based on the characterization tests of fresh and spent sorbents. A kinetic study for the regeneration of spent sorbents was also conducted. The activation energies of mercury desorption from various substrates were calculated and the corresponding mercury desorption profiles were mathematically modeled.

Download or read book COMBINED THEORETICAL AND EXPERIMENTAL INVESTIGATION OF MECHANISMS AND KINETICS OF VAPOR PHASE MERCURY UPTAKE BY CARBONACEOUS SURFACES written by and published by . This book was released on 2000 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The overall goal of this research program is to gain fundamental understanding of the important chemistry and physics involved in mercury adsorption on carbonaceous surfaces. This knowledge will then be used to optimize adsorption processes and operating conditions to maximize the uptake of mercury within the required contact time. An additional long-term benefit of this research is the basic understanding of the Hg adsorption process, which may facilitate the design of new adsorbents for more efficient and cost-effective removal of Hg from a variety of effluent streams. Molecular modeling of the adsorption of Hg on carbonaceous surfaces will greatly increase the insight into the physics of the adsorption process and combined with in situ rate measurements of mercury adsorption and desorption (conventional and pulsed laser) on graphite using linear and nonlinear optical probes with real time optical resolution have the potential to provide fundamental insight into the process of mercury uptake by carbonaceous surfaces. Besides accurate assessment of key parameters influencing adsorption equilibrium, fundamental understanding of the kinetics of mercury adsorption, desorption, and diffusion will be developed in this study. These key physical and chemical processes postulated through molecular modeling efforts and verified by in situ measurements will be utilized to select (or develop) promising sorbents for mercury control, which will be tested under dynamic conditions using simulated flue gas.

Download or read book Experimental and Kinetic Study of Mercury Adsorption on Various Activated Carbons in a Fixed Bed Adsorber written by Youngkil Lee and published by . This book was released on 2003 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Kinetic Study of Mercury Sorption Desorption Process on Sorbents written by T. C. Ho and published by . This book was released on 1999 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling of Mercury Desorption from Activated Carbon at Elevated Temperatures Under Fluidized fixed Bed Operations written by T. C. Ho and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Adsorption Calculations and Modelling written by Howard Brenner and published by Elsevier. This book was released on 2013-10-22 with total page 257 pages. Available in PDF, EPUB and Kindle. Book excerpt: 'Adsorption Calculations and Modelling' provides readers with practical, useful information about how to make adsorption calculations and formulate models describing adsorption processes. Unlike most books on this subject, this book treats both gas phase adsorption and liquid phase adsorption with equal emphasis, and supplies a rigorous treatment of multi-component adsorption. It also covers adsorption applications in environmental applications including the use of impregnated adsorbents for protection against toxic gases and carbon adsorption in water and wastewater treatment.Explores the most up-to-date information on multicomponent adsorption Details adsorption applications in environmental application Explains the fundamentals of adsorption calculation in a simple, straightforward manner.

Download or read book Mercury Oxidation and Adsorption Over Cupric Chloride based Catalysts and Sorbents for Mercury Emissions Control written by Xin Li and published by . This book was released on 2012 with total page 189 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mercury emissions control is of great importance in environment protection as well as public health. Current mercury emissions control technologies are not well designed nor optimized, mainly due to the lack of fundamental understanding of adsorption and/or catalytic mechanisms and necessary kinetic modeling and reliable simulation data. This work aims to advance the fundamental mechanistic understanding of heterogeneous catalytic oxidation reaction and adsorption by using the reaction between Hg(0) vapor and CuCl2 and the subsequent adsorption of resultant oxidized mercury onto sorbents. XANES and EXAFS were used to determine mercury compounds formed on AC sorbents. The XANES study on raw and CuCl2-impregnated AC sorbents suggests that little or no elemental mercury is formed onto any spent sorbents and the chemisorption of Hg(0) vapor is very likely to be the dominant mechanism. HgCl2 is found to be a major oxidation reaction product when CuCl2 and HCl were impregnated onto raw AC regardless of the type of the carrier gas (i.e. N2 or O2). The adsorption isotherms of HgCl2 on DARCO-HG and CuCl2-impregnated AC were found to be of the Langmuir type. The kinetic adsorption constants were estimated by fitting the model simulation with experimental data. The breakthrough data from experiments are in good agreement with the calculation results from the modified kinetic model. The simulation results indicate that pore diffusion resistance significantly increases with an increase in sorbent particle size. HgCl2 adsorption removal performance was also predicted in an entrained flow system using a modified model. The CuCl2/[alpha]-Al2O3 catalyst possesses high activity for the oxidation of Hg(0) to Hg2+, with an excellent stability under the environment similar to the flue gas from coal-fired power plants. The CuCl2 crystallites formed onto [alpha]-Al2O3 were very stable up to 300oC, and undergo the thermal reduction process from Cu(II) to Cu(0) via Cu(I). In the absence of HCl and O2 gases, CuCl2 was found to follow a Mars-Maessen mechanism by consuming lattice chlorine of CuCl2 for Hg(0) oxidation and to be reduced to CuCl. In the presence of 10 ppmv HCl, 2,000 ppmv SO2, and 6% O2 gases, the CuCl2/[alpha]-Al2O3 sample works as an Hg(0) oxidation catalyst exhibiting>90% conversion with good resistance to SO2 at 140oC. The reduced CuCl was able to be re-chlorinated to CuCl2 under HCl and O2 gases by following the Deacon reaction. Multiple copper species were found to be formed when [gamma]-Al2O3 is used as a substrate as opposed to one Cu(II) species on [alpha]-Al2O3. The CuCl2/[gamma]-Al2O3 catalysts with low CuCl2 loading (

Download or read book written by and published by . This book was released on 1969 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Adsorption and Desorption of Mercury from Sorbents in a Hot Air Stream written by Amit Ghai and published by . This book was released on 1996 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book L din Max 1919 written by and published by . This book was released on 1939 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Zeitungsausschnitte.

Download or read book Adsorption Analysis Equilibria And Kinetics With Cd Containing Computer Matlab Programs written by Duong D Do and published by World Scientific. This book was released on 1998-09-22 with total page 915 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers topics of equilibria and kinetics of adsorption in porous media. Fundamental equilibria and kinetics are dealt with for homogeneous as well as heterogeneous particles. Five chapters of the book deal with equilibria and eight chapters deal with kinetics. Single component as well as multicomponent systems are discussed. In kinetics analysis, we deal with the various mass transport processes and their interactions inside a porous particle. Conventional approaches as well as the new approach using Maxwell-Stefan equations are presented. Various methods to measure diffusivity, such as the Differential Adsorption Bed (DAB), the time lag, the diffusion cell, chromatography, and the batch adsorber methods are also covered by the book. It can be used by lecturers and engineers who wish to carry out research in adsorption. A number of programming codes written in MatLab language are included so that readers can use them directly to better understand the behavior of single and multicomponent adsorption systems.

Download or read book Design Simulation and Optimization of Adsorptive and Chromatographic Separations A Hands On Approach written by Kevin R. Wood and published by John Wiley & Sons. This book was released on 2018-07-16 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive resource to the construction, use, and modification of the wide variety of adsorptive and chromatographic separations Design, Simulation and Optimization of Adsorptive and Chromatographic Separations offers the information needed to effectively design, simulate, and optimize adsorptive and chromatographic separations for a wide range of industrial applications. The authors?noted experts in the field?cover the fundamental principles, the applications, and a range of modeling techniques for the processes. The text presents a unified approach that includes the ideal and intermediate equations and offers a wealth of hands-on case studies that employ the rigorous simulation packages Aspen Adsorption and Aspen Chromatography. The text reviews the effective design strategies, details design considerations, and the assumptions which the modelers are allowed to make. The authors also cover shortcut design methods as well as mathematical tools that help to determine optimal operating conditions. This important text: -Covers everything from the underlying pheonmena to model optimization and the customization of model code -Includes practical tutorials that allow for independent review and study -Offers a comprehensive review of the construction, use, and modification of the wide variety of adsorptive and chromatographic separations -Contains contributions from three noted experts in the field Written for chromatographers, process engineers, ehemists, and other professionals, Design, Simulation and Optimization of Adsorptive and Chromatographic Separations offers a comprehensive review of the construction, use, and modification of adsorptive and chromatographic separations.

Download or read book Green Adsorbents written by George Z. Kyzas and published by Bentham Science Publishers. This book was released on 2015-12-01 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: Adsorption technology is a promising avenue for wastewater treatment. Numerous adsorbent materials are presently synthesized. Green or environmental friendly adsorbents are derived from plants and agricultural crop sources, giving them a very low production cost when compared to synthetic polymers. This monograph explains the basic principles of green adsorption technology, their production processes and strategies to remove different categories of environmental pollutants (dyes, heavy metals and phenols/pesticides). The book explains details in terms of features such as adsorption capacity, physico-chemical kinetics and reuse potential. A summary of the economics and future prospect for green adsorption technology is also given. This text is a handy reference for environmental chemistry students, researchers and policy makers.