DOCSLIB.ORG

Ethylbenzene Dehydrogenation Into Styrene: Kinetic Modeling and Reactor Simulation

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Ethylbenzene Dehydrogenation Into Styrene: Kinetic Modeling and Reactor Simulation ETHYLBENZENE DEHYDROGENATION INTO STYRENE: KINETIC MODELING AND REACTOR SIMULATION A Dissertation by WON JAE LEE Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY December 2005 Major Subject: Chemical Engineering ETHYLBENZENE DEHYDROGENATION INTO STYRENE: KINETIC MODELING AND REACTOR SIMULATION A Dissertation by WON JAE LEE Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Approved by: Co-Chairs of Committee, Rayford G. Anthony Gilbert F. Froment Committee Members, Daniel F. Shantz Michael P. Rosynek Head of Department, Kenneth R. Hall December 2005 Major Subject: Chemical Engineering iii ABSTRACT Ethylbenzene Dehydrogenation into Styrene: Kinetic Modeling and Reactor Simulation. (December 2005) Won Jae Lee, B.S., SungKyunKwan University; M.S., Pohang University of Science and Technology Co-Chairs of Advisory Committee: Dr. Rayford G. Anthony Dr. Gilbert F. Froment A fundamental kinetic model based upon the Hougen-Watson formalism was derived as a basis not only for a better understanding of the reaction behavior but also for the design and simulation of industrial reactors. Kinetic experiments were carried out using a commercial potassium-promoted iron catalyst in a tubular reactor under atmospheric pressure. Typical reaction conditions were temperature = 620oC, steam to ethylbenzene mole ratio = 11, and partial pressure of N2 diluent = 0.432 bar. Experimental data were obtained for different operating conditions, i.e., temperature, feed molar ratio of steam to ethylbenzene, styrene to ethylbenzene, and hydrogen to ethylbenzene and space time. The effluent of the reactor was analyzed on-line using two GCs. Kinetic experiments for the formation of minor by-products, i.e. phenylacetylene, α-methylstyrene, β-methylstyrene, etc, were conducted as well. The reaction conditions were: temperature = 600oC ~ 640oC, a molar ratio of steam to ethylbenzene = 6.5, and iv partial pressure of N2 diluent = 0.43 bar and 0.64 bar. The products were analyzed by off-line GC. The mathematical model developed for the ethylbenzene dehydrogenation consists of nonlinear simultaneous differential equations in multiple dependent variables. The parameters were estimated from the minimization of the multiresponse objective function which was performed by means of the Marquardt algorithm. All the estimated parameters satisfied the statistical tests and physicochemical criteria. The kinetic model yielded an excellent fit of the experimental data. The intrinsic kinetic parameters were used with the heterogeneous fixed bed reactor model which is explicitly accounting for the diffusional limitations inside the porous catalyst. Multi-bed industrial adiabatic reactors with axial flow and radial flow were simulated and the effect of the operating conditions on the reactor performance was investigated. The dynamic equilibrium coke content was calculated using detailed kinetic model for coke formation and gasification, which was coupled to the kinetic model for the main reactions. The calculation of the dynamic equilibrium coke content provided a crucial guideline for the selection of the steam to ethylbenzene ratio leading to optimum operating conditions. v To my late grandfather To my parents To my wife vi ACKNOWLEDGEMENTS I would never have made it without the help of a lot of people around me. I gratefully acknowledge Dr. Rayford G. Anthony and Dr. Gilbert F. Froment, co-chairs of committee, for their guidance, patience, and encouragement during my research. I wish to thank Dr. Daniel F. Shantz and Dr. Michael P. Rosynek for serving as the advisory committee members. I would like to thank my friends in the Kinetics, Catalysis, and Reaction Engineering Laboratory for the friendship, help and discussions: Dr. Xianchun Wu, Dr. Sunghyun Kim, Rogelio Sotelo, Bradley Atkinson, Hans Kumar, Luis Castaneda, Celia Marin, and Nicolas Rouckout. I am grateful for sharing the priceless friendship with my fellow Korean students in the Department of Chemical Engineering. I also thank all the members in Vision Mission Church for their countless prayers in my Lord Jesus Christ. I thank my parents and parents-in-law for their prayers and support throughout the years. Most importantly, I would like to thank my wife, Sohyun Park, for the encouragement and love she has given me ever since I pursued the degree. vii TABLE OF CONTENTS Page ABSTRACT................................................................................................................. iii DEDICATION ............................................................................................................. v ACKNOWLEDGEMENTS ......................................................................................... vi TABLE OF CONTENTS............................................................................................. vii LIST OF FIGURES...................................................................................................... xii LIST OF TABLES ....................................................................................................... xix CHAPTER I INTRODUCTION....................................................................................... 1 II LITERATURE REVIEW............................................................................ 4 2.1 Chemistry of Ethylbenzene Dehydrogenation................................... 4 2.2 Role of Promoter in Ethylbenzene Dehydrogenation ........................ 4 2.3 Role of Steam in Ethylbenzene Dehydrogenation............................. 9 2.4 Kinetics of Ethylbenzene Dehydrogenation ...................................... 10 2.5 Kinetics of Coke Formation............................................................... 14 2.5.1 Introduction............................................................................ 14 2.5.2 Deactivation by Site Coverage............................................... 17 2.5.3 Deactivation by Site Coverage and Pore Blockage ............... 18 2.6 Deactivation Phenomena in Ethylbenzene Dehydrogenation............ 19 2.7 Industrial Processes............................................................................ 20 2.7.1 Adiabatic Reactor................................................................... 20 2.7.2 Isothermal Reactor................................................................. 22 2.8 Alternative Processes......................................................................... 22 2.9 Minor by-products in Ethylbenzene Dehydrogenation...................... 23 2.9.1 Impurities in Styrene Monomer............................................. 23 2.9.2 Specification of Styrene Monomer ........................................ 24 viii CHAPTER Page III EXPERIMENTAL METHODS.................................................................. 27 3.1 Introduction........................................................................................ 27 3.2 Feed and Reactor Section................................................................... 27 3.3 GC Analysis Section.......................................................................... 33 3.3.1 On-line GC Analysis for Major Reactions............................. 33 3.3.2 Off-line GC Analysis for Minor Side Reactions.................... 37 3.4 Catalyst Characterization: Nitrogen Adsorption................................ 42 IV EXPERIMENTAL RESULTS.................................................................... 43 4.1 Experimental Results for the Major Reactions .................................. 43 4.1.1 Experimental Procedure......................................................... 43 4.1.2 Nitrogen Adsorption.............................................................. 45 4.1.3 Long Run Test........................................................................ 47 4.1.4 Effect of Temperature............................................................ 54 4.1.5 Effect of Feed Composition................................................... 59 4.1.5.1 Effect of Steam to Ethylbenzene Feed Ratio........... 59 4.1.5.2 Effect of Styrene to Ethylbenzene Feed Ratio ........ 59 4.1.5.3 Effect of Hydrogen to Ethylbenzene Feed Ratio..... 63 4.2 Experimental Results for the Minor Side Products............................ 68 4.2.1 Experimental Procedure......................................................... 68 4.2.2 Effect of Temperature and Partial Pressure of Ethylbenzene and Steam........................................................ 69 V KINETIC MODELING OF ETHYLBENZENE DEHYDROGENATION............................................................................. 77 5.1 Introduction........................................................................................ 77 5.2 Formulation of Rate Equations .......................................................... 79 5.2.1 Thermal Reactions ................................................................. 79 5.2.2 Catalytic Reactions................................................................ 81 5.3 Formulation of Continuity Equations for the Reacting Species ........ 85 5.4 Parameter Estimation: Theory ........................................................... 90 5.4.1 Minimization Technique: Marquardt Method ....................... 90 5.4.2 Reparameterization ................................................................ 93 5.5 Results and Discussion.....................................................................
Load more

Recommended publications
  • Toxicological Profile for Ethylbenzene
    ETHYLBENZENE 221 9. REFERENCES Abraham MH, Ibrahim A, Acree WE. 2005. Air to blood distribution of volatile organic compounds: A linear free energy analysis. Chem Res Toxicol 18(5):904-911. ACGIH. 1992. 1992-1993 Threshold limit values for chemical substances and physical agents and biological exposure indices. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, 21. ACGIH. 2002. Ethylbenzene. Documentation of the threshold limit values for chemical substances and physical agents and biological exposure indices. 7th ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists. ACGIH. 2006. Ethylbenzene. Threshold limit values for chemical substances and physical agents and biological exposure indices. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, 29, 104. Acton DW, Barker JF. 1992. In situ biodegradation potential of aromatic hydrocarbons in anaerobic groundwaters. J Contam Hydrol 9:325-352. Adinolfi M. 1985. The development of the human blood-CSF-brain barrier. Dev Med Child Neurol 27(4):532-537. Adlercreutz H. 1995. Phytoestrogens: Epidemiology and a possible role in cancer protection. Environ Health Perspect Suppl 103(7):103-112. Agency for Toxic Substances and Disease Registry. 1989. Decision guide for identifying substance- specific data needs related to toxicological profiles; Notice. Agency for Toxic Substances and Disease Registry, Division of Toxicology. Fed Regist 54(174):37618-37634. Agency for Toxic Substances and Disease Registry. 1990. Biomarkers of organ damage or dysfunction for the renal, hepatobiliary and immune systems. Subcommittee on Biomarkers of Organ Damage and Dysfunction. Atlanta, GA: Agency for Toxic Substances and Disease Registry. Agency for Toxic Substances and Disease Registry. 1992. Toxicological profile for styrene.
    [Show full text]
  • Ethylbenzene- Toxfaqs™ CAS # 100-41-4
    Ethylbenzene- ToxFAQs™ CAS # 100-41-4 This fact sheet answers the most frequently asked health questions (FAQs) about ethylbenzene. For more information, call the CDC Information Center at 1-800-232-4636. This fact sheet is one in a series of summaries about hazardous substances and their health effects. It is important you understand this information because this substance may harm you. The effects of exposure to any hazardous substance depend on the dose, the duration, how you are exposed, personal traits and habits, and whether other chemicals are present. HIGHLIGHTS: Ethylbenzene is a colorless liquid found in a number of products including gasoline and paints. Breathing very high levels can cause dizziness and throat and eye irritation. Breathing lower levels has resulted in hearing effects and kidney damage in animals. Ethylbenzene has been found in at least 829 of 1,699 National Priorities List (NPL) sites identified by the Environmental Protection Agency (EPA). What is ethylbenzene? • Releases of ethylbenzene into the air occur from burning oil, gas, and coal and from industries Ethylbenzene is a colorless, flammable liquid that smells using ethylbenzene. like gasoline. • Ethylbenzene is not often found in drinking water. It is naturally found in coal tar and petroleum and is also Higher levels may be found in residential drinking found in manufactured products such as inks, pesticides, water wells near landfills, waste sites, or leaking and paints. underground fuel storage tanks. Ethylbenzene is used primarily to make another chemical, • Exposure can occur if you work in an industry where styrene. Other uses include as a solvent, in fuels, and to ethylbenzene is used or made.
    [Show full text]
  • BUTADIENE AS a CHEMICAL RAW MATERIAL (September 1998)
    Abstract Process Economics Program Report 35D BUTADIENE AS A CHEMICAL RAW MATERIAL (September 1998) The dominant technology for producing butadiene (BD) is the cracking of naphtha to pro- duce ethylene. BD is obtained as a coproduct. As the growth of ethylene production outpaced the growth of BD demand, an oversupply of BD has been created. This situation provides the incen- tive for developing technologies with BD as the starting material. The objective of this report is to evaluate the economics of BD-based routes and to compare the economics with those of cur- rently commercial technologies. In addition, this report addresses commercial aspects of the butadiene industry such as supply/demand, BD surplus, price projections, pricing history, and BD value in nonchemical applications. We present process economics for two technologies: • Cyclodimerization of BD leading to ethylbenzene (DSM-Chiyoda) • Hydrocyanation of BD leading to caprolactam (BASF). Furthermore, we present updated economics for technologies evaluated earlier by PEP: • Cyclodimerization of BD leading to styrene (Dow) • Carboalkoxylation of BD leading to caprolactam and to adipic acid • Hydrocyanation of BD leading to hexamethylenediamine. We also present a comparison of the DSM-Chiyoda and Dow technologies for producing sty- rene. The Dow technology produces styrene directly and is limited in terms of capacity by the BD available from a world-scale naphtha cracker. The 250 million lb/yr (113,000 t/yr) capacity se- lected for the Dow technology requires the BD output of two world-scale naphtha crackers. The DSM-Chiyoda technology produces ethylbenzene. In our evaluations, we assumed a scheme whereby ethylbenzene from a 266 million lb/yr (121,000 t/yr) DSM-Chiyoda unit is combined with 798 million lb/yr (362,000 t/yr) of ethylbenzene produced by conventional alkylation of benzene with ethylene.
    [Show full text]
  • Ethylbenzene Environmental Hazard Summary
    ENVIRONMENTAL CONTAMINANTS ENCYCLOPEDIA ETHYLBENZENE ENTRY July 1, 1997 COMPILERS/EDITORS: ROY J. IRWIN, NATIONAL PARK SERVICE WITH ASSISTANCE FROM COLORADO STATE UNIVERSITY STUDENT ASSISTANT CONTAMINANTS SPECIALISTS: MARK VAN MOUWERIK LYNETTE STEVENS MARION DUBLER SEESE WENDY BASHAM NATIONAL PARK SERVICE WATER RESOURCES DIVISIONS, WATER OPERATIONS BRANCH 1201 Oakridge Drive, Suite 250 FORT COLLINS, COLORADO 80525 WARNING/DISCLAIMERS: Where specific products, books, or laboratories are mentioned, no official U.S. government endorsement is implied. Digital format users: No software was independently developed for this project. Technical questions related to software should be directed to the manufacturer of whatever software is being used to read the files. Adobe Acrobat PDF files are supplied to allow use of this product with a wide variety of software and hardware (DOS, Windows, MAC, and UNIX). This document was put together by human beings, mostly by compiling or summarizing what other human beings have written. Therefore, it most likely contains some mistakes and/or potential misinterpretations and should be used primarily as a way to search quickly for basic information and information sources. It should not be viewed as an exhaustive, "last-word" source for critical applications (such as those requiring legally defensible information). For critical applications (such as litigation applications), it is best to use this document to find sources, and then to obtain the original documents and/or talk to the authors before depending too heavily on a particular piece of information. Like a library or most large databases (such as EPA's national STORET water quality database), this document contains information of variable quality from very diverse sources.
    [Show full text]
  • A New Perspective on Catalytic Dehydrogenation of Ethylbenzene: the Influence of Side-Reactions on Catalytic Performance
    Catalysis Science & Technology A new perspective on catalytic dehydrogenation of ethylbenzene: the influence of side-reactions on catalytic performance Journal: Catalysis Science & Technology Manuscript ID: CY-ART-03-2015-000457.R1 Article Type: Paper Date Submitted by the Author: 18-May-2015 Complete List of Authors: Gomez Sanz, Sara; University of Cambridge, Department of Chemical Engineering and Biotechnology McMillan, Liam; University of Cambridge, Department of Chemical Engineering and Biotechnology McGregor, James; University of Sheffield, Department of Chemical and Biological Engineering Zeitler, J.; University of Cambridge, Department of Chemical Engineering; Al-Yassir, Nabil; King Fahd University of Petroleum & Minerals, Center of Research Excellence in Petroleum Refining and Petrochemical Khattaf, Sulaiman; King Fahd University of Petroleum and Minerals, Center of Research Excellence in Petroleum Refining and Petrochemical Gladden, Lynn; University of Cambridge, Department of Chemical Engineering and Biotechnology, Page 1 of 44 Catalysis Science & Technology The direct dehydrogenation of ethylbenzene to styrene over CrO x/Al 2O3 proceeds via a partially oxidative mechanism due to the formation of CO 2 in situ during reaction. Other side reactions, including coke formation, also play a key role in dictating catalytic performance. Catalysis Science & Technology Page 2 of 44 A new perspective on catalytic dehydrogenation of ethylbenzene: the influence of side-reactions on catalytic performance Sara Gomez a, Liam McMillan a, James
    [Show full text]
  • Supporting Information for Modeling the Formation and Composition Of
    Supporting Information for Modeling the Formation and Composition of Secondary Organic Aerosol from Diesel Exhaust Using Parameterized and Semi-explicit Chemistry and Thermodynamic Models Sailaja Eluri1, Christopher D. Cappa2, Beth Friedman3, Delphine K. Farmer3, and Shantanu H. Jathar1 1 Department of Mechanical Engineering, Colorado State University, Fort Collins, CO, USA, 80523 2 Department of Civil and Environmental Engineering, University of California Davis, Davis, CA, USA, 95616 3 Department of Chemistry, Colorado State University, Fort Collins, CO, USA, 80523 Correspondence to: Shantanu H. Jathar ([email protected]) Table S1: Mass speciation and kOH for VOC emissions profile #3161 3 -1 - Species Name kOH (cm molecules s Mass Percent (%) 1) (1-methylpropyl) benzene 8.50×10'() 0.023 (2-methylpropyl) benzene 8.71×10'() 0.060 1,2,3-trimethylbenzene 3.27×10'(( 0.056 1,2,4-trimethylbenzene 3.25×10'(( 0.246 1,2-diethylbenzene 8.11×10'() 0.042 1,2-propadiene 9.82×10'() 0.218 1,3,5-trimethylbenzene 5.67×10'(( 0.088 1,3-butadiene 6.66×10'(( 0.088 1-butene 3.14×10'(( 0.311 1-methyl-2-ethylbenzene 7.44×10'() 0.065 1-methyl-3-ethylbenzene 1.39×10'(( 0.116 1-pentene 3.14×10'(( 0.148 2,2,4-trimethylpentane 3.34×10'() 0.139 2,2-dimethylbutane 2.23×10'() 0.028 2,3,4-trimethylpentane 6.60×10'() 0.009 2,3-dimethyl-1-butene 5.38×10'(( 0.014 2,3-dimethylhexane 8.55×10'() 0.005 2,3-dimethylpentane 7.14×10'() 0.032 2,4-dimethylhexane 8.55×10'() 0.019 2,4-dimethylpentane 4.77×10'() 0.009 2-methylheptane 8.28×10'() 0.028 2-methylhexane 6.86×10'()
    [Show full text]
  • Recommendations for Exposure-Based Assessmentpdf Icon
    60 3. Recommendation for Exposure-Based Assessment of Joint Toxic Action of the Mixture Benzene, toluene, ethylbenzene, and xylenes frequently occur together at hazardous waste sites. The four chemicals are volatile and have good solvent properties. Toxicokinetic studies in humans and animals indicate that these chemicals are well absorbed, distribute to lipid-rich and highly vascular tissues such as the brain, bone marrow, and body fat due to their lipophilicity, and are rapidly eliminated from the body (Appendices A, B, C, and D). Metabolism of the four chemicals is dose-dependent and generally extensive at dose levels that do not saturate the first metabolic step of each compound, which involves cytochrome P-450-dependent mixed function oxidases. The predominant cytochrome P-450 isozyme involved in the metabolism of each chemical is CYP2E1. As discussed in Chapter 2 and the Appendices, all four chemicals can produce neurological impairment via parent compound-induced physical and chemical changes in nervous system membranes. Exposure to benzene can additionally cause hematological effects including aplastic anemia, with subsequent manifestation of acute myelogenous leukemia, via the action of reactive metabolites. No data are available on toxic or carcinogenic responses to whole mixtures of BTEX. To conduct exposure-based assessments of possible health hazards from BTEX in the absence of these data, a component-based approach that considers both the shared (neurologic) and unique (hematologic/ immunologic/carcinogenic) critical effects of the chemicals is recommended. In particular, as explained below, it is advised that (1) the Hazard Index approach be used to assess the joint neurotoxic hazard of the four mixture components, and (2) the hematological and carcinogenic hazards be assessed on a benzene- specific basis.
    [Show full text]
  • Ethylbenzene
    Ethylbenzene 100-41-4 Hazard Summary Ethylbenzene is mainly used in the manufacture of styrene. Acute (short-term) exposure to ethylbenzene in humans results in respiratory effects, such as throat irritation and chest constriction, irritation of the eyes, and neurological effects such as dizziness. Chronic (long-term) exposure to ethylbenzene by inhalation in humans has shown conflicting results regarding its effects on the blood. Animal studies have reported effects on the blood, liver, and kidneys from chronic inhalation exposure to ethylbenzene. Limited information is available on the carcinogenic effects of ethylbenzene in humans. In a study by the National Toxicology Program (NTP), exposure to ethylbenzene by inhalation resulted in an increased incidence of kidney and testicular tumors in rats, and lung and liver tumors in mice. EPA has classified ethylbenzene as a Group D, not classifiable as to human carcinogenicity. Please Note: The main sources of information for this fact sheet are EPA's Integrated Risk Information System (IRIS) (5), which contains information on inhalation and oral chronic toxicity of ethylbenzene and the RfC, and oral chronic toxicity and the RfD, and the Agency for Toxic Substances and Disease Registry's (ATSDR's) Toxicological Profile for Ethylbenzene. (1) Uses Ethylbenzene is used primarily in the production of styrene. It is also used as a solvent, as a constituent of asphalt and naphtha, and in fuels. (1) Sources and Potential Exposure In one study, ethylbenzene was detected in urban air at a median concentration of 0.62 parts per billion (ppb). The median level in suburban air was about 0.62 ppb, while the mean level measured in air in rural locations was about 0.13 ppb.
    [Show full text]
  • APPENDIX a Speciated Compounds NMOC
    APPENDIX A Speciated Compounds This appendix lists chemical species measured from the NMOC, PM2.5, and toxics monitoring programs. You can use this appendix to determine the corresponding AQS parameter code. For information on which sites monitor for speciated NMOC, PM2.5, or toxics data, see Table 1, "Air Quality Monitoring Data Availability". Compound Name AQS Parameter Code NMOC 1,2,3-Trimethylbenzene 45225 1,2,4-Trimethylbenzene 45208 1,3,5-Trimethylbenzene 45207 1,3-Butadiene 43218 1-Butene 43280 1-Pentene 43224 2,2,3-Trimethylbutane 43392 2,2,4-Trimethylpentane 43250 2,2-Dimethylbutane 43244 2,3,4-Trimethylpentane 43252 2,3-Dimethylbutane 43284 2,3-Dimethylpentane 43291 2,4-Dimethylpentane 43247 2,5-Dimethylhexane 43955 2-Methyl-1-Pentene 43246 2-Methyl-2-Butene 43228 2-Methylbutane 43221 2-Methylheptane 43960 2-Methylhexane 43263 2-Methylpentane 43285 3-Ethylhexane 43295 3-Methylbutene 43282 3-Methylheptane 43253 3-Methylhexane 43249 3-Methylpentane 43230 4-Mpentene/3-Mpentene 43391 Benzene 45201 Butane 43212 6 - 1 Compound Name AQS Parameter Code c-1,3-Dimethylcypentane 43393 c-2-Butene 43217 c-2-Hexene 43290 c-2-Pentene 43227 Cyclohexane 43248 Cyclopentane 43242 Cyclopentene 43283 Decane 43238 Ethane 43202 Ethene 43203 Ethylbenzene 45203 Ethyne 43206 Heptane 43232 Hexane 43231 Isobutane 43214 Isobutene 43270 Isoprene 43243 Iso-Propylbenzene 45210 m/p-Xylene 45109 m-Diethylbenzene 45218 Methylcyclohexane 43261 Methylcyclopentane 43262 m-Ethyltoluene 45212 Nonane 43235 n-Propylbenzene 45209 n-Undecane 43954 Octane 43233 o-Ethyltoluene
    [Show full text]
  • Risk Based Concentrations for Ethylbenzene & Naphthalene
    Oregon Department of Environmental Quality Underground Storage Tank Program HEATING OIL TANK CONTRACTOR BULLETIN HEATING OIL TANK PROGRAM UPDATE UPDATED RISK BASED CONCENTRATIONS FOR ETHYLBENZENE AND NAPHTHALENE December 2008 Our mission is to be an active leader in restoring, maintaining and enhancing the quality of Oregon’s air, water and land. Carcinogen Reclassification Lowers RBCs The Environmental Protection Agency (EPA) has issued updated screening levels for 1,1-Dichloroethane, ethylbenzene, and naphthalene that significantly reduce OR DEQ’s Risk Based Concentrations (RBCs) for these contaminants. The rationale for the RBC decrease was the reclassification of these contaminants from non carcinogens to carcinogens. The table below compares the RBCs published in July 4, 2007 with the updated RBCs for ethylbenzene and naphthalene. 1,1-Dichlorethane was omitted from the table as it is not a contaminant that the HOT Program requires in sample analysis during assessment and cleanup. Soil (mg/kg) * July 2007 RBC Updated RBC Soil Ingestion, Dermal Contact, and Inhalation Ethylbenzene 4,000 27 Naphthalene 34 3.8 Leaching to Groundwater Ethylbenzene 160 0.14 Naphthalene 3.8 0.072 Volatilization to Indoor Air Ethylbenzene No previous RBC 0.69 Naphthalene 290 5.5 Volatilization to Outdoor Air Ethylbenzene No previous RBC 26 Naphthalene 240 4.5 Groundwater (ug/L) * Ingestion and Inhalation from tapwater Ethylbenzene 1,300 1.2 Naphthalene 6.2 0.12 Volatilization to Indoor Air Ethylbenzene No previous RBC 410 Naphthalene 29,000 560 Volatilization
    [Show full text]
  • Ethylbenzene Etb
    ETHYLBENZENE ETB CAUTIONARY RESPONSE INFORMATION 4. FIRE HAZARDS 7. SHIPPING INFORMATION 4.1 Flash Point: 80°F O.C. 59°F C.C. 7.1 Grades of Purity: Research grade: 99.98%; Common Synonyms Liquid Colorless Sweet, gasoline- 4.2 Flammable Limits in Air: 1.0%-6.7% pure grade: 99.5%; technical grade: 99.0% EB like odor 4.3 Fire Extinguishing Agents: Foam (most 7.2 Storage Temperature: Ambient Phenylethane effective), water fog, carbon dioxide or 7.3 Inert Atmosphere: No requirement dry chemical. Floats on water. Flammable, irritating vapor is produced. 7.4 Venting: Open (flame arrester) or pressure- 4.4 Fire Extinguishing Agents Not to Be vacuum Keep people away. Avoid contact with liquid and vapor. Used: Not pertinent 7.5 IMO Pollution Category: B Avoid inhalation. 4.5 Special Hazards of Combustion Wear goggles, self-contained breathing apparatus, and rubber overclothing (including gloves). Products: Irritating vapors are 7.6 Ship Type: 3 Shut off ignition sources and call fire department. generated when heated. 7.7 Barge Hull Type: Currently not available Stay upwind and use water spray to ``knock down'' vapor. 4.6 Behavior in Fire: Vapor is heavier than Notify local health and pollution control agencies. air and may travel considerable distance Protect water intakes. 8. HAZARD CLASSIFICATIONS to the source of ignition and flash back. 4.7 Auto Ignition Temperature: 860°F 8.1 49 CFR Category: Flammable liquid FLAMMABLE. 8.2 49 CFR Class: 3 Fire Flashback along vapor trail may occur. 4.8 Electrical Hazards: Not pertinent Vapor may explode if ignited in an enclosed area.
    [Show full text]
  • Region Viii Pretreatment Guidance on the Analysis of Btex
    REGION VIII PRETREATMENT GUIDANCE ON THE ANALYSIS OF BTEX August 9, 1999 The analysis of total BTEX (benzene, toluene, ethylbenzene and xylenes) is often required of industrial users discharging petroleum contaminated groundwater to municipal wastewater treatment plants. Monitoring performed under the Pretreatment Regulations (40 CFR Part 403) must be in accordance with methods specified under 40 CFR Part 136. Analytical methods for the analysis of benzene, toluene, and ethylbenzene are specified in 40 CFR Part 136. However, there are no methods approved under 40 CFR Part 136 for the analysis of total xylene. EPA Region VIII recognizes that the analytical methods specified in 40 CFR Part 136 for benzene, toluene, and ethylbenzene are valid methods for the analysis of total xylene. The concentration of benzene, toluene, ethylbenzene, and total xylene must be added together to obtain a value for total BTEX. Total xylene is represented by three isomers (commonly referred to as meta- para- and ortho- xylene). The concentration for the three isomers are added together to obtain a value for total xylene. 40 CFR Part 136 methods will not provide adequate resolution to separate meta- and para- xylene. Therefore meta- and para-xylene will be represented by a single value. Total xylene is then computed by adding the concentration of ortho-xylene to the concentration representing both meta- and para-xylene. The following table is a summary of methods approved under 40 CFR Part 136 (as of March 1, 1993) for the analysis of benzene, ethylbenzene, and toluene. Parameter EPA Approved Methods benzene EPA Methods 602, 624, 1624 Standard Methods 17th Edition 6210 B, 6220 B toluene " " ethylbenzene " " (OVER) The EPA Region VIII Pretreatment Program recommends the use of the above methods for the analysis of total xylene.
    [Show full text]