Rapid and Automated Determination of Plutonium and Neptunium in Environmental Samples Risø-PhD-Report Jixin Qiao Risø-PhD-75(EN) March 2011 Author: Jixin Qiao Risø-PhD-75(EN) March 2011 Title: Rapid and Automated Determination of Plutonium and Neptunium in Environmental Samples Division: Radiation Research Division This thesis is submitted in fulfilment of requirements for the Ph. D. degree at Risø National Laboratory for Sustainable Energy, Technical University of Denmark. Abstract: ISBN 978-87-550-3889-9 This thesis presents improved analytical methods for rapid and automated determination of plutonium and neptunium in environmental samples using sequential injection (SI) based chromatography and inductively coupled plasma mass spectrometry (ICP-MS). The progress of methodology development in this work consists of 5 subjects stated as follows: 1) Development and optimization of an SI-anion exchange chromatographic method for rapid determination of plutonium in environmental samples in combination of inductively coupled plasma mass spectrometry detection (Paper II); Group's own reg. no.:1400110-05 (2) Methodology development and optimization for rapid determination of plutonium in environmental samples using SI- extraction chromatography prior to inductively coupled plasma mass spectrometry (Paper III); (3) Development of an SI-chromatographic method for simultaneous determination of plutonium and neptunium in environmental samples (Paper IV); 242 (4) Investigation of the suitability and applicability of Pu as a tracer for rapid neptunium determination using anion exchange chromatography in an SI-network coupled with inductively coupled plasma mass spectrometry (Paper V); (5) Exploration of macro-porous anion exchange chromatography for rapid and simultaneous determination of plutonium and neptunium within an SI system (Paper VI). The results demonstrate that the developed methods in this study are reliable and efficient for accurate assays of trace levels of plutonium and neptunium as demanded in different situations including environmental risk monitoring and assessment, emergency preparedness and surveillance of contaminated areas. Pages:124 Tables:8 References:97 Information Service Department Risø National Laboratory for Sustainable Energy Technical University of Denmark P.O.Box 49 DK-4000 Roskilde Denmark Telephone +45 46774005 [email protected] Fax +45 46774013 www.risoe.dtu.dk Thesis for the Degree of Doctor of Philosophy Radiation Research Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark Rapid and Automated Determination of Plutonium and Neptunium in Environmental Samples Jixin Qiao To be presented with the permission of the Radiation Research Division for public criticism in Risø – DTU, Roskilde, Denmark on 17th March, 2011. Roskilde 2011 Summary in Danish Denne afhandling præsenterer forbedrede analysemetoder til hurtig og automatisk bestemmelse af plutonium og neptunium i miljøprøver ved brug af sekventiel injektion (SI) baseret på kromatografi og massespektrometri med induktivt koblet plasma (ICP-MS). Metodeudviklingen for dette arbejde er beskrevet i følgende fem artikler. 1) Udvikling og optimering af en kromatografisk metode med SI-anionbytter til hurtig bestemmelse af plutonium i miljøprøver kombineret med bestemmelse ved massespektrometri med induktivt koblet plasma (Artikel II); 2) Metodeudvikling og optimering til hurtig bestemmelse af plutonium i miljøprøver ved brug af SI-ekstraktionskromatografi og massespektrometri med induktivt koblet plasma (Artikel III); 3) Udvikling af en SI-kromatografisk metode til samtidig bestemmelse af plutonium og neptunium i miljøprøver (Artikel IV); 4) Undersøgelse af egnethed og anvendelse af 242Pu som sporstof for hurtig bestemmelse af neptunium med anionbytterkromatografi i et SI-netværk kombineret med massespektrometri med induktivt koblet plasma (Artikel V); 5) Undersøgelse af makro-porøs anionbytterkromatografi til hurtig og samtidig bestemmelse af plutonium og neptunium med et SI-system (Artikel VI). Resultaterne viser, at de udviklede metoder er pålidelige og effektive og giver nøjagtige analyseresultater for spormængder af plutonium og neptunium som krævet i tilfælde af overvågning og vurdering af miljørisici, beredskab og overvågning af forurenede områder. Custos Senior scientist Xiaolin Hou Radiation Research Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark Roskilde, Denmark Opponents Senior scientist Sven P. Nielsen Radiation Research Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark Roskilde, Denmark Professor Elo H. Hansen Professor of Analytical Chemistry Lyngby, Denmark Professor Jukka Lehto Laboratory of Radiochemistry, Department of Chemistry University of Helsinki Helsinki, Finland 1 Abstract This thesis presents improved analytical methods for rapid and automated determination of plutonium and neptunium in environmental samples using sequential injection (SI) based chromatography and inductively coupled plasma mass spectrometry (ICP-MS). The progress of methodology development in this work consists of 5 subjects stated as follows: 1) Development and optimization of an SI-anion exchange chromatographic method for rapid determination of plutonium in environmental samples in combination of inductively coupled plasma mass spectrometry detection (Paper II); 2) Methodology development and optimization for rapid determination of plutonium in environmental samples using SI-extraction chromatography prior to inductively coupled plasma mass spectrometry (Paper III); 3) Development of an SI-chromatographic method for simultaneous determination of plutonium and neptunium in environmental samples (Paper IV); 4) Investigation of the suitability and applicability of 242Pu as a tracer for rapid neptunium determination using anion exchange chromatography in an SI-network coupled with inductively coupled plasma mass spectrometry (Paper V); 5) Exploration of macro-porous anion exchange chromatography for rapid and simultaneous determination of plutonium and neptunium within an SI system (Paper VI). The results demonstrate that the developed methods in this study are reliable and efficient for accurate assays of trace levels of plutonium and neptunium as demanded in different situations including environmental risk monitoring and assessment, emergency preparedness and surveillance of contaminated areas. 2 Preface The present study was carried out at the Radioecology and Tracer Programme, Radiation Research Division, Risø National Laboratory for Sustainable Energy, Technical University of Denmark (DTU), during 2008-2011. I am deeply grateful to Professor Guoan Ye, who was guiding me through the master studies of radiochemistry and offering me the chance to continue my PhD study in Denmark. I am sincerely grateful to Senior Scientist Sven Nielsen who gave me the opportunity to work in his group and advising and encouraging me throughout the whole period of my PhD study. My best supervisor Senior Scientist Xiaolin Hou, thank you so much for cultivating and guiding me during my three-year PhD study! Your broad experiences and excellent ideas always refresh me. You gave me a number of invaluable comments, suggestions, advices and enormous encouragements supporting me to finalize the work. You always trusted me and gave me freedom to exploit my thoughts and insights. I indeed grew up a lot and gained impressive progress with your instruction and support. I very warmly thank Senior Scientist Per Roos who transferred his invaluable experiences to me, directed me to understand and gradually discover the trueness of scientific research and connected me with the ICP-MS and radiometric detections. I wish to express my sincere thanks to Associate Professor Manuel Miró who gave me great support and guided in my PhD study, especially during the three-month external exercitation in Spain and channelled me into the coupling of flow-based analyzer with direct ICP-MS detection. I express my dearest thanks to Professor Victor Cerdà who gave me solid support and help with assembling of my experimental setup during my three-month external exercitation in his group in Spain. My greatest gratitude goes to my friend Roongrat Petersen for transferring all her knowledge and experiences in flow techniques to me and instructing me to design and assemble the first sequential injection setup for the initiation of my experiment. I am honestly appreciative to my friend Yixuan for assistance with the operation of environmental sample separation at the beginning of my PhD study. I sincerely thank my friend Jussi who spent a great amount of effort and time to help me with the ICP- MS measurement and Kasper who gave me a number of constructive comments for my PhD research and warm welcome for collaborations. I am also very grateful to my friends Violeta, Keliang, Haijun, Maoyi and Yukun who gave me a full support during my PhD study as well as the preparation of this thesis. I thank Professor Elo Hansen and Professor Jukka Lehto for critically reviewing the dissertation and offering constructive comments. All my friends, colleague and the whole radiation research division are warmly thanked and remembered for all the happy moments, good laughs, tricky discussion, and successful manoeuver and co-operations. My friends Liga, Birgitte, Annete, Jytte, Kristina, Susanne, Lars, Clause, Majbritt, Martin, Ole, Svend, Yusuf and Charlotte, have been giving me a lot of spirit needed for the