page0920 |
Previous | 1 of 17 | Next |
|
|
Loading content ...
THE EFFECTS OF CHLORINE ON THE PROPERTIES AND PERFORMANCE OF ACTIVATED CARBON Walter J. Weber, Jr., Professor College of Engineering The University of Michigan Ann Arbor, Michigan 48109 James D. Sherrill, Project Manager Massoud Pirbazari, Engineer Environmental Dynamics, Inc. Ann Arbor, Michigan 48104 INTRODUCTION This chapter details results from an investigation of potential effects of high concentrations of avadable chlorine compounds (HOC1 and OC1") and chlorate (C103") on activated carbon adsorption systems. The study relates to direct treatment of industrial waste streams containing these compounds, as well as to industrial discharges of such materials to municipal facdities which incorporate activated carbon treatment. Activated carbon is frequently used for dechlorination of waters and wastewaters. That contact of HOC1/OC." with carbon wdl result in chemical reduction of these compounds is well known. It is therefore conceivable that sufficiently high concentrations of HOC1/OC1" might ultimately cause oxidative degradation of carbon and/or impair its adsorptive functions. Although the rates and extent of removal of HOCl/OCf by carbon have been elaborated in some detad [ 1 ] there is little quantitative information available with respect to concentrations of these oxidizing agents that can be tolerated without adverse effects on the carbon. The behavior of C103", which has a higher thermodynamic oxidation potential than HOC1/OC1", is even less weU known. The oxidation potential of C103~ is not effectively exercised in ddute aqueous systems because of high associated activation energies, and thus insignificant rates of reaction. However, the possibUity for surface catalysis of the reduction of C103" by activated carbon-a recognized catalyst for many oxidation/ reduction reactions-has not been explored in this context. In view of the increasing significance of activated carbon in industrial and municipal wastewater treatment and the lack of information regarding potential interactions with the aforementioned chlorine compounds, the present study was designed and executed to develop a data base upon which to assess the effects, if any, of selected concentrations of these compounds on the physical and chemical properties of activated carbon, and on its function as an adsorbent. The concentrations selected for study exceed those that might be anticipated for most treatment situations, and therefore represent a conservative boundary condition for evaluating whether adverse effects are manifest by the presence of HOC1/OC1" and/or C103" in activated carbon treatment systems. SCOPE AND EXPERIMENTAL DETAIL It is generally recognized that the adsorptive characteristics and physical properties of an activated carbon wdl change as a function of successive exhaustions and regenerations, the extent of change being determined in large measure by the type of carbon, the waste stream being treated, and the conditions of regeneration. The investigations described in this chapter were designed to evaluate whether HOC1/OC." and/or C103", even in very large concentrations, have statistically significant effects on the rates and extent of such changes. 920
Object Description
Purdue Identification Number | ETRIWC197991 |
Title | Effects of chlorine on the properties and performance of activated carbon |
Author |
Weber, Walter J. Sherrill, James D. Pirbazari, Massoud |
Date of Original | 1979 |
Conference Title | Proceedings of the 34th Industrial Waste Conference |
Conference Front Matter (copy and paste) | http://e-archives.lib.purdue.edu/u?/engext,30453 |
Extent of Original | p. 920-936 |
Collection Title | Engineering Technical Reports Collection, Purdue University |
Repository | Purdue University Libraries |
Rights Statement | Digital object copyright Purdue University. All rights reserved. |
Language | eng |
Type (DCMI) | text |
Format | JP2 |
Date Digitized | 2009-06-24 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Resolution | 300 ppi |
Color Depth | 8 bit |
Description
Title | page0920 |
Collection Title | Engineering Technical Reports Collection, Purdue University |
Repository | Purdue University Libraries |
Rights Statement | Digital copyright Purdue University. All rights reserved. |
Language | eng |
Type (DCMI) | text |
Format | JP2 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Transcript | THE EFFECTS OF CHLORINE ON THE PROPERTIES AND PERFORMANCE OF ACTIVATED CARBON Walter J. Weber, Jr., Professor College of Engineering The University of Michigan Ann Arbor, Michigan 48109 James D. Sherrill, Project Manager Massoud Pirbazari, Engineer Environmental Dynamics, Inc. Ann Arbor, Michigan 48104 INTRODUCTION This chapter details results from an investigation of potential effects of high concentrations of avadable chlorine compounds (HOC1 and OC1") and chlorate (C103") on activated carbon adsorption systems. The study relates to direct treatment of industrial waste streams containing these compounds, as well as to industrial discharges of such materials to municipal facdities which incorporate activated carbon treatment. Activated carbon is frequently used for dechlorination of waters and wastewaters. That contact of HOC1/OC." with carbon wdl result in chemical reduction of these compounds is well known. It is therefore conceivable that sufficiently high concentrations of HOC1/OC1" might ultimately cause oxidative degradation of carbon and/or impair its adsorptive functions. Although the rates and extent of removal of HOCl/OCf by carbon have been elaborated in some detad [ 1 ] there is little quantitative information available with respect to concentrations of these oxidizing agents that can be tolerated without adverse effects on the carbon. The behavior of C103", which has a higher thermodynamic oxidation potential than HOC1/OC1", is even less weU known. The oxidation potential of C103~ is not effectively exercised in ddute aqueous systems because of high associated activation energies, and thus insignificant rates of reaction. However, the possibUity for surface catalysis of the reduction of C103" by activated carbon-a recognized catalyst for many oxidation/ reduction reactions-has not been explored in this context. In view of the increasing significance of activated carbon in industrial and municipal wastewater treatment and the lack of information regarding potential interactions with the aforementioned chlorine compounds, the present study was designed and executed to develop a data base upon which to assess the effects, if any, of selected concentrations of these compounds on the physical and chemical properties of activated carbon, and on its function as an adsorbent. The concentrations selected for study exceed those that might be anticipated for most treatment situations, and therefore represent a conservative boundary condition for evaluating whether adverse effects are manifest by the presence of HOC1/OC1" and/or C103" in activated carbon treatment systems. SCOPE AND EXPERIMENTAL DETAIL It is generally recognized that the adsorptive characteristics and physical properties of an activated carbon wdl change as a function of successive exhaustions and regenerations, the extent of change being determined in large measure by the type of carbon, the waste stream being treated, and the conditions of regeneration. The investigations described in this chapter were designed to evaluate whether HOC1/OC." and/or C103", even in very large concentrations, have statistically significant effects on the rates and extent of such changes. 920 |
Resolution | 300 ppi |
Color Depth | 8 bit |
Tags
Comments
Post a Comment for page0920