Desorption of moisture from stainless steel tubes and alumina filters in high purity gas distribution systems

The mechanism of moisture desorption from both stainless steel and 80% alumina surfaces is studied. A difficulty associated with moisture is its strong adsorption on various gas distribution surfaces and its slow desorption due to a very high activation energy. A unique experimental setup to determine desorption under gas flow conditions by monitoring the moisture concentration at the system outlet is described. A simple analytical technique is presented to analyze the desorption data so acquired, in an effort to normalize the results and thus making them system independent. Desorption rate constants for stainless steel and ceramic (80% alumina) surfaces are calculated using this model at a constant temperature.<
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