der Georg-August-Universiät zu Göttingen

• Main Authors: Formation From Ice Ih, Doroteya Kancheva Staykova, Aus Stara Zagora (bulgarien, Dr. W. F. Kuhs
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Methane hydrate
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.633.4364; http://ediss.uni-goettingen.de/bitstream/handle/11858/00-1735-0000-0006-B54E-E/staykova.pdf?sequence=1

This thesis work reports on the kinetics of methane hydrate formation from ice Ih powder at conditions of hydrate stability below the quadruple point in order to address open issues on gas hydrate growth. It was conducted in the framework of a DFG-project Ku 920/9 devoted to the study of ice surfaces and ice interfaces. In this work for the first time results of different experimental methods studying the gas hydrate growth were combined and checked for consistency. Valuable quantitative information of the methane hydrate formation was obtained by neutron diffraction and gas consumption measurements. Similar studies were also attempted on the hydrate growth using X-ray diffraction. An unexpected formation of metastable type II CO2-hydrate together with the ordinary type I was observed by neutron diffraction during the initial growth process. Gas consumption measurements during the methane hydrate growth showed the long-term development reaching an almost full conversion to a hydrate. Scanning electron microscopy provided images of various stages of the transformation of ice to hydrate and guided the development of a phenomenological multistage model of gas hydrate growth from polydisperse