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The Reduction of Ytterbium (III) to Ytterbium (II)

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The Reduction of Ytterbium (III) to Ytterbium (II) University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Masters Theses Graduate School 5-2007 The Reduction of Ytterbium (III) to Ytterbium (II) Amanda S. Jones University of Tennessee - Knoxville Follow this and additional works at: https://trace.tennessee.edu/utk_gradthes Part of the Chemistry Commons Recommended Citation Jones, Amanda S., "The Reduction of Ytterbium (III) to Ytterbium (II). " Master's Thesis, University of Tennessee, 2007. https://trace.tennessee.edu/utk_gradthes/251 This Thesis is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Masters Theses by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a thesis written by Amanda S. Jones entitled "The Reduction of Ytterbium (III) to Ytterbium (II)." I have examined the final electronic copy of this thesis for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Master of Science, with a major in Chemistry. George K. Schweitzer, Major Professor We have read this thesis and recommend its acceptance: Jamie L. Adcock, Michael J. Sepaniak Accepted for the Council: Carolyn R. Hodges Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) To the Graduate Council: I am submitting herewith a thesis written by Amanda Shirlene Jones entitled “The Reduction of Ytterbium (III) to Ytterbium (II).” I have examined the final electronic copy of this thesis for form and content and recommend that it be accepted in partial fulfillment of the requirements for the degree Master of Science, with a major in Chemistry. George K. Schweitzer Major Professor We have read this thesis and recommend its acceptance: Jamie L. Adcock Michael J. Sepaniak Accepted for the Council: Linda Painter Interim Dean of the Graduate School (Original Signatures are on file with official student records.) THE REDUCTION OF YTTERBIUM (III) TO YTTERBIUM (II) A Thesis Presented for the Master of Science Degree The University of Tennessee, Knoxville Amanda Shirlene Jones May 2007 ACKNOWLEDGEMENTS This work could not have been accomplished without the support and advice of Dr. George K. Schweitzer. The author wishes to extend her appreciation and gratitude to Dr. Schweitzer for his encouragement, inspiration, and the opportunity to work in his laboratory. The author would also like to thank her committee members Dr. Jamie L. Adcock and Dr. Michael J. Sepaniak for their flexibility and advice. The author was privileged to work with Mrs. Elissa M. LaPointe and would like to thank her for her friendship, memories, ideas, and endless discussions. The author is extremely indebted to her parents, Daniel and Deborah Frank, who have provided endless love, support, and guidance throughout the years. The author would also like to thank her husband, Jess Jones for his love, patience, and encouragement. ii ABSTRACT If Yb(III) could be reduced to the highly unstable Yb(II), and temporarily stabilized, the separation of Yb from the other lanthanide elements could be facilitated. This facilitation would be based upon the considerably different chemistry of Yb(II) from the trivalent forms of all other lanthanides. The reduction of Yb(III) to Yb(II) using Mg was attempted in various media. The effects of the media, precipitating agent, and environment were examined. The best experimental conditions for the reduction of Yb(III) to Yb(II) and the subsequent precipitation of YbSO4 were found to be the addition of ~0.35 g YbCl38H2O in 1.5 mL 3:1 ethanol:dioxane and 0.05 mL 17.4 M acetic acid to 0.15 g tetramethylammonium sulfate and ~0.20 g of 50 mesh Mg powder under nitrogen and over ice. Under these conditions, a maximum of 85% of the Yb(II) could be removed from the system. iii TABLE OF CONTENTS CHAPTER PAGE I. INTRODUCTION ...........................................................................1 A. Introduction................................................................................1 B. History........................................................................................2 C. Proposed Research.....................................................................8 II. EXPERIMENTAL APPROACH...................................................11 A. Basic System............................................................................11 B. Chemicals.................................................................................11 C. Apparatus .................................................................................11 1. Test Tube ..................................................................11 2. Modified Test Tube...................................................14 3. Column......................................................................16 D. Analysis....................................................................................20 III. EXPERIMENTAL RESULTS.......................................................21 IV. CONCLUSION..............................................................................48 LIST OF REFERENCES.......................................................................................49 VITA......................................................................................................................53 iv LIST OF TABLES TABLE PAGE 1. Chemicals.......... ..................................................................................12 2. Yb(III) reduction with redox ions in sulfate system ............................22 3. Yb(III) reduction with redox ions in chloride system..........................22 4. Yb(III) reduction with omission of single redox ions in chloride System............... ..................................................................................23 5. Yb(III) reduction without redox ions...................................................24 6. Additional Yb(III) reduction reactions without redox ions .................25 7. Yb(III) reduction timed trials...............................................................25 8. Yb(III) reduction with addition of Na2SO4 ..........................................26 9. Yb(III) reduction and then, addition of 0.1 M Na2SO4........................27 10. Yb(III) reduction and then, addition of 0.5 M Na2SO4........................27 11. Yb(III) reduction and then, addition of 1.0 M Na2SO4........................28 12. Lu(III) and then, addition of 1.0 M Na2SO4 ........................................28 13. Yb(III) reduction in various solvents...................................................29 14. AE analysis for successful experiments (I-44 through I-85) ...............30 15. Yb(III) reduction in CH3CN with HCl.................................................31 16. Yb(III) reduction in CH3CN with HOAc ............................................31 17. Lu(III) reactions in CH3CN .................................................................32 18. Yb(III) reduction in CH3CN with HCl, addition of 1.0 M Na2SO4 .....32 19. Lu(III) in CH3CN with HCl, addition of 1.0 M Na2SO4......................33 v 20. Yb(III) and Lu(III) in CH3CN system .................................................34 21. Yb(II) addition to 0.5 M (NH4)2SO4 ....................................................37 22. Yb(II) addition to 1.0 M (NH4)2SO4 ....................................................37 23. Yb(II) addition to 1.5 M (NH4)2SO4 ....................................................37 24. Yb(II) addition to TMAMS .................................................................38 25. Observations of Yb(II) addition to TMAMS.......................................39 26. Yb(II) addition to TMAS.....................................................................40 27. Observations Yb(II) addition to TMAS...............................................40 28. Yb(III) addition to TMAS....................................................................40 29. Yb(II) addition to TMAS with Observations.......................................40 30. Yb(II) addition to TMAS dissolved in EtOH:1,4-dioxane:H2O in HOAc............ ..................................................................................41 31. Yb(II) addition to TMAS dissolved in EtOH:1,4-dioxane:H2O (1) ....41 32. Yb(II) addition to TMAS dissolved in EtOH:1,4-dioxane:H2O (2) ....42 33. Yb(II) addition to TMAS dissolved in EtOH:1,4-dioxane:H2O (3) ....42 34. Yb(II) addition to TMAS dissolved in EtOH:1,4-dioxane:H2O (4) ....43 35. Timed Yb(II) addition to TMAS..........................................................45 vi LIST OF FIGURES FIGURE PAGE 1. Simple System Setup ...........................................................................15 2. Sealed Setup with Syringe and Gas Dispersion Tube..........................15 3. Sealed Setup Using 3-neck Round Bottom Flask................................17 4. 3-neck Round Bottom Flask with Test Tube Attached........................17 5. Initial Mg Column Setup .....................................................................18 6. Second Mg Column Apparatus............................................................18 7. Third Mg Column Apparatus...............................................................19 vii Chapter 1 INTRODUCTION A. Introduction One of the best, if not the best, scintillation detectors for high energy photons
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