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Technetium and Rhenium in Volcanic Soils by Icpms UNLV Retrospective Theses & Dissertations 1-1-2006 Technetium and rhenium in volcanic soils by Icpms Clifton Lee Jones University of Nevada, Las Vegas Follow this and additional works at: https://digitalscholarship.unlv.edu/rtds Repository Citation Jones, Clifton Lee, "Technetium and rhenium in volcanic soils by Icpms" (2006). UNLV Retrospective Theses & Dissertations. 2053. http://dx.doi.org/10.25669/fmt8-xke5 This Thesis is protected by copyright and/or related rights. It has been brought to you by Digital Scholarship@UNLV with permission from the rights-holder(s). You are free to use this Thesis in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/ or on the work itself. This Thesis has been accepted for inclusion in UNLV Retrospective Theses & Dissertations by an authorized administrator of Digital Scholarship@UNLV. For more information, please contact [email protected]. TECHNETIUM AND RHENIUM IN VOECANIC SOIES BY ICPMS by Clifton Lee Jones Bachelor o f Science University of Nevada, Las Vegas 1979 A thesis submitted in partial fulfillment of the requirements for the Master of Science Degree in Chemistry Department of Chemistry College of Sciences Graduate College University of Nevada, Las Vegas December 2006 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 1441710 INFORMATION TO USERS The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleed-through, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. UMI UMI Microform 1441710 Copyright 2007 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Thesis Approval UME The Graduate College University of Nevada, Las Vegas November 1 7_____^20 06 The Thesis prepared by Clifton Lee Jones E ntitled Technetium and Rhenium in Volcanic Soils by ICPMS is approved in partial fulfillment of the requirements for the degree of Master of Science in Chemistry______________ Examination Committee Chair Dean of the Graduate College //^ ' / Exnmif-mtion Committee Member Examinntion Committee Member Graduate Colhye Faculty Representative 11 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ABSTRACT Technetium and Rhenium in Volcanic Soils by ICPMS by Clifton Lee Jones Dr. Vernon F. Hodge Examination Committee Chair Professor of Chemistry Elniversity of Nevada, Las Vegas Technetium-99 (^^Tc) and rhenium (Re) were determined in volcanic tuff muck rock, from the potential repository at Yucca Mountain and in nuclear bomb cavity samples from the Nevada Test Site (NTS). These analyses were performed in order to test the feasibility of using high resolution inductively couple plasma mass spectrometry (HR- ICPMS) for the determination of ^^Tc. Six 20 gram tuff samples were analyzed in duplicate for*^*^Tc and Re following separation using an anion exchange resin to remove potential interferences. Four nuclear bomb cavity samples were analyzed using one gram samples. A '^'^Te method detection limit (MDL) of 33 pg/kg (parts per quadrillion (ppq)) was achieved; however the tuff samples analyses results were all less than this concentration. The average Re concentration of the six tuff samples was 23 ng/kg (ppt) with an average relative standard deviation (RSD) of 7.5%. The nuclear bomb cavity samples ^Tc analyses results ranged from 330 to 11,800 pg/kg (ppq). Ill Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS ABSTRACT ...............................................................................................................................................iii LIST OF FIGURES ................................................................................................................................ vi LIST OF TABLES ................................................................................................................................. vii ACKNOWLEDGEMENTS............................................................................................................... viii CHAPTER 1 INTRODUCTION .................................................................................................... 1 Yucca Mountain Project ...................................................................................................................I Geologic Setting ..................................................................................................................................3 Purpose of Study ...............................................................................................................................12 T ech n etiu m ........................................................................................................................................28 R henium .............................................................................................................................................. 35 CHAPTER 2 LITERATURE SEARCH .................................................................................... 40 Background and Rationale ............................................................................................................ 40 Technetium Literature Review ....................................................................................................40 Rhenium Literature Search ...........................................................................................................44 Review of Analytical M ethods ....................................................................................................45 CHAPTER3 METHODOLOGY ...................................................................................................58 Research Approach ..........................................................................................................................58 Sample Preparation ..........................................................................................................................60 Sample Analyses .............................. 69 CHAPTER 4 RESULTS AND DISCUSSION .........................................................................73 Tuff Samples Analyses Results .................................................................................................. 73 Bomh Cavity Samples Analyses Results .................................................................................84 CHAPTER 5 CONCLUSION .......................................................................................................93 Future W ork .......................................................................................................................................94 APPENDIX 1 PERCENT MASS ABUNDENCES FOR TC AND RE REGIONS 98 APPENDIX 11 ORISE/ESSAP AP5 DETERMINATION OF TECHNETlUM-99 100 APPENDIX 111 SAMPLE PREPARATION PROCEDURE................................................111 IV Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. REFERENCES ......................................................................................................................................114 VITA ......................................................................................................................................................... 124 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. LIST OF FIGURES Figure 1 Underground Layout of the Proposed Repository .......................................................3 Figure 2 Geostratigraphy at Yucca Mountain ............................................................................... 5 Figure 3 Vertical Eithostratigraphy and Geochronology of Yucca Mountain .....................8 Figure 4 Yucca Mountain Eithostratigraphy and Potential Repository Horizon ..............11 Figure 5 Bomb.Pulse of ^^Cl Measured in Glacier Ice Cores from Greenland ................. 16 Figure 6 Yucca Mountain ESF Tunnel with Overlay Showing the Ratios of ^^Cl/Cl .. 17 Figure 7 Evolution of an Underground Nuclear Cavity ...........................................................23 Figure 8 Bomb Cavity with Distribution of Radionuclides .................................................. 24 Figure 9 Eh-pH Diagram of Aqueous Species of Technetium .........................................34 Figure 10 Eh-pH Diagram of Aqueous Species of Rhenium ....................................................39 Figure 11 Graph of the k’ Number of Free Volumes to Peak for '^'^Tc Exchange Resin. 53 Figure 12 Flow Chart of the Sample Preparation Procedure ....................................................59 Figure 13
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