As-mineral-humic substance interactions [Elektronische Ressource] : influence of natural organic matter on sorption and mobility of As / vorgelegt von Prasesh Sharma

As-mineral-humic substance interactions – Influence of natural organic matter on sorption and mobility of As Dissertation zur Erlangung des Grades eines Doktors der Naturwissenschaften der Geowissenschaftlichen Fakultät der Eberhard Karls Universität Tübingen vorgelegt von Prasesh Sharma Kathmandu, Nepal 2010 Tag der mündlichen Prüfung: Sept 24. 2010 Dekan: Prof. Dr. Peter Grathwohl 1. Berichterstatter: Prof. Dr. Andreas Kappler 2. Berichterstatter: Dr. Andreas Voegelin TABLE OF CONTENTS 1. Introduction 1 2. Formation of binary and ternary colloids and dissolved complexes of organic matter, Fe and As 16 3. Influence of organic matter on As transport and retention 31 4. Effect of humic acid on As(V) desorption from ferrihydrite-coated sand at different ionic strength 64 2+5. Surface binding site analysis of Ca -homoionized clay-humic acid complexes 78 6. Effect of dissolved phosphate and silicate on As desorption from clay and humic acid-coated clay 88 7. Conclusions and outlook 114 8. Summary (in English and in German) 122 9. Publications list 135 10. Statement of personal contribution 136 11.