Estamos realizando la búsqueda. Por favor, espere...

Gas transport properties of interfacially polymerized polyamide composite membranes under different pre-treatments and temperatures

Abstract: Thin-film composite reverse osmosis membranes were dried under different membrane pre-treatment procedures and evaluated at increased temperatures by gas separation tests. The obtained permeance and selectivity values indicated the presence of highly-permeable regions in the dry samples of the commercial membranes. Treatment with etanol-hexane in a solvent exchange process, as well as membrane immersion in t-butanol followed by freeze drying, increased the gas permeance by a factor of 1.8 to 9, and from 1.6 to 3.2, respectively, by comparison with room temperature and oven drying. Nevertheless, a Knudsendiffusion transport mechanism was dominant after both pre-treatments. The permeation temperature remarkably influenced gas selectivity and permeance, and a máximum He/N2 selectivity occurred at 150 1C with considerable high permeance results, which may suggest the use of polyamide membranes as alternative materials for high-temperature separation processes. The temperature-induced changes in the polymer structure and in the transport of compounds can be explained by Knudsen and activated diffusion mechanisms throughout a highly-permeable regions and a dense polyamide matrix, respectively.

 Fuente: Journal of Membrane Science, 2014, 449, 109-118

 Editorial: Elsevier

 Fecha de publicación: 01/01/2014

 Nº de páginas: 10

 Tipo de publicación: Artículo de Revista

 DOI: 10.1016/j.memsci.2013.08.026

 ISSN: 0376-7388,1873-3123

 Url de la publicación: https://doi.org/10.1016/j.memsci.2013.08.026