Sorption thermosiphon apparatus (STA): A novel and accurate system for gas mixtures sorption measurements. (April 2020)

• Record Type: Journal Article
• Authors: Fioravante Rezende, Carolina Guedes; Amaral, Rafael Aislan; Habert, Alberto Claudio; Borges, Cristiano Piacsek
• Is Part Of: Polymer testing. Volume 84(2020)
• Publication Date: 2020-04
• Subjects: Membranes -- Plasticizing -- Pressure decay -- Diffusion -- Permeation; Polymers -- Testing -- Periodicals; Polymères -- Tests -- Périodiques; 620.1920287
• DOI: 10.1016/j.polymertesting.2020.106382
• Languages: English
• ISSNs: 0142-9418

Abstract

Abstract: One of the main challenges in membrane gas separation is the plasticizing effect that reduces selectivity. For a better understanding of this phenomenon, the knowledge of the sorption behavior of each component of the mixture is necessary. For this purpose, the sorption thermosyphon apparatus (STA), was successfully designed and tested with gas sorption measurements. One of the main advantages of the STA compared to actual other methods is to ensure concentration uniformity at the headspace using a thermosiphon, as pressure decay is recorded. The equilibrium condition is not disturbed during the sampling and allow the obtention of accurate data at the end of the sorption experiment. To validate the novel system, the sorption, diffusion and permeation coefficients of pure CO2 and CH4, as well as for a CO2 /CH4 (50/50) mixture, in polydimethylsiloxane (PDMS) were obtained through STA and other experimental techniques showing good agreement with literature data. Highlights: The sorption thermosyphon apparatus (STA), was successfully designed and tested with gas sorption measurements. Compared to actual other methods, the STA allow to ensure concentration uniformity at the headspace using a thermosiphon. In the STA, the equilibrium condition is not disturbed during the sampling, this allow the obtention of more accurate data. Sorption, diffusion and permeation of pure and mixed CO2 and CH4 in polydimethylsiloxane (PDMS) were obtained by STA.