Group separation of complex mixtures by normal-phase high performance liquid chromatography and analysis by gas chromatography [Elektronische Ressource] / Amritpal Soor

Amrit Gomperts

Informations

• Publié par: universitat_ulm
• Publié le: 01 janvier 2007
• Nombre de lectures: 22
• Langue: English
• Poids de l'ouvrage: 48 Mo

Extrait

University of Ulm
Institute for Analytical and Environmental Chemistry
Germany
Prof. Dr. K. Ballschmiter


Group Separation of Complex Mixtures by Normal-
Phase High Performance Liquid Chromatography and
Analysis by Gas Chromatography







A thesis submitted for the degree of
Dr. rer. nat.
at the University of Ulm
Germany
Faculty of Natural Sciences


Amritpal Soor
Huddersfield
England

2007


































University of Ulm
Institute for Analytical and Environmental Chemistry
Germany
Prof. Dr. K. Ballschmiter


Group Separation of Complex Mixtures by Normal-
Phase High Performance Liquid Chromatography and
Analysis by Gas Chromatography







A thesis submitted for the degree of
Dr. rer. nat.
at the University of Ulm
Germany
Faculty of Natural Sciences


Amritpal Soor
Huddersfield
England

2007





























Dean: Prof. Dr. Klaus-Dieter Spindler
st1 Supervisor: Prof. Dr. Karlheinz Ballschmiter (University of Ulm)
nd2Prof. Dr. Manfred Ayasse m)
Graduation date: 18 July 2008













“My grandfather once told me that there are two kinds of people: those who
work and those who take the credit. He told me to try to be in the first group;
there was less competition there.”

Indira Gandhi










For my parents…




































Acknowledgements

I would like to start by thanking my supervisor, Prof. Dr. Karlheinz Ballschmiter for the
opportunity to carry out this work at the University of Ulm in the Institute for Analytical
and Environmental Chemistry. I am extremely appreciative of the continuous support, help
and advice throughout this thesis. The theme for this work involves the use of compounds
that are a topic of current concern for environmentalists and atmospheric chemists as
climate change and pollution affect us all.
Next I would like to thank my second supervisor Prof. Dr. Jan Andersson for taking the
time to read this work.

Acknowledgement to Prof. Dr. Welsch for the help and advice with analytical problems
encountered during my studies. I am also indebted to Dr. U. Reuter, for the talks on life
and politics and to Marie Bowman who has kept me sane when my head has been unable
to switch into German mode!
I am also grateful to Dr. H. Buchert who has always been willing and able to help with the
repairing of instrumentation.

The department has been a very friendly environment to work and this is down to the
department members. I would therefore like to give a special mention to my PhD
colleagues, Stefan Woidich, Oliver Eberhardt and Anke Grünert who have helped and
assisted me throughout my time at the University. I have had a most enjoyable time both in
and out of the work place.
Sandra Gienger I would like to acknowledge for her help and enthusiasm especially whilst
writing. During this time I have learnt that the correct expression is not “Ich bin
langweilig” but “Mir ist langweilig”!

Finally I cannot adequately express my gratitude to my parents Gurdeep & Balbinder and
my brothers Harpreet & Mandeep, who have always been available for chats about life,
jobs, cars and most importantly in times of need. The ‘SMS’ “Mum can you call me at
work please x” - will be missed!



































Contents

1 Introduction ...........................................................................................................................1
1.1 The problem with the separation of extremely complex organic mixtures ......................1
1.2 History and examples from the literature .........................................................................3
1.3 Source of complex mixtures.............................................................................................5
1.4 Aims of the thesis .............................................................................................................8
1.5 Nomenclature ...................................................................................................................8
2 The air we breathe...............................................................................................................10
2.1 Air as a mobile phase for the global dispersal of pollutants...........................................10
2.2 Esters of nitric acid as complex mixtures found in the atmosphere ...............................22
2.3 Alkyl nitrites as complex mixtures.................................................................................28
2.4 Organic nitrates of isoprene in air ..................................................................................29
2.5 Persistent organic pollutants as complex mixtures found in the atmosphere.................30
3 Chromatography: Theory and application.......................................................................35
3.1 Normal-phase liquid chromatography (NP-LC).............................................................35
3.1.1 Adsorption of water in NP-HPLC42
3.2 Solvent strength and the eluotropic series ......................................................................43
3.3 The eluotropic strength on carbon adsorbents................................................................46
+3.4 Normal phase chromatography using Ag stationary phases .........................................47
3.5 Mobile phase selectivity in NP-HPLC ...........................................................................48
3.6 Separation and detectors in gas chromatography ...........................................................50
3.6.1 Electron capture detector (ECD) .........................................................................52
3.6.2 Mass spectrometric detector (MSD)....................................................................53
3.6.2.1 Ion formation ...........................................................................................56
3.6.2.2 Ion separation ..........................................................................................60
3.6.2.3 Ion detection ............................................................................................61
4 Instruments, reagents and separation conditions.............................................................63
4.1 Gas chromatography (GC)..............................................................................................63
4.2 High performance liquid chromatography (HPLC)........................................................67 Contents
4.3 Reference standards........................................................................................................ 68
4.4 Air sampling equipment ................................................................................................. 68
4.5 General laboratory equipment........................................................................................ 69
4.6 Instrumentation used ...................................................................................................... 69
5 Air sampling procedure 70
5.1 Previously used sampling methods ................................................................................ 70
5.2 Pre-cleaning of the adsorbent......................................................................................... 76
5.3 Trace enrichment of analytes by the high volume adsorptive sampling of air .............. 77
5.4 Collection of data ........................................................................................................... 77
5.5 Liquid extraction of the analytes from the adsorbent..................................................... 80
5.6 Group separation by NP-HPLC and analysis by HRGC................................................ 81
6 Geographical locations of the air samples......................................................................... 83
6.1 University of Ulm in continental mainland Europe ....................................................... 83
6.2 Island of Madeira in the North Atlantic Ocean.............................................................. 84
6.2.1 Description of the sampling locations on the Island of Madeira......................... 86
7 Preparation