Gas Permeation through Polydimethylsiloxane Membranes: Comparison of Three Model Combinations

Abstract

The modeling of a gas mixture permeating through a polymeric membrane can be achieved by the combination of a mass transfer model with a thermodynamic model. In this study, three model combinations, i.e., the combination of Fick's law with Henry's law (F‐H), that of Fick's law with the UNIQUAC equation (F‐U), and that of the Maxwell‐Stefan equation with the UNIQUAC equation (MS‐U), were solved by iteration computer procedure to predict the separation performance of both binary and ternary gas mixtures permeating through a polydimethylsiloxane membrane. The predicted results were analyzed in detail and compared with experimental results. It was found that there are remarkable differences among the considered model combinations in predicting separation performance, and these differences tend to become larger with increasing solubility. Among the three considered model combinations, MS‐U gives the prediction closest to the experimental results. Its advantage over the other two model combinations should be due to the proper estimation of the permeate solubility by the UNIQUAC equation and the reasonable consideration of mass transfer resistance by the Maxwell‐Stefan equation.

Sub-Ocean: Subsea Dissolved Methane Measurements Using an Embedded Laser Spectrometer Technology

“…Extraction of dissolved gases from seawater was performed using a silicon rubber membrane, for which the technology has previously been described in terms of physical properties such as adsorption, permeation, and desorption. − Existing sensors, including commercial instruments from Contros (Kongsberg), Franatech, Los Gatos Research, and Pro-Oceanus, employ membrane extraction for measuring dissolved gases. , Membrane extraction techniques found in the literature rely on gas equilibration across the membrane that allows for precise measurements of dissolved gas concentration, at the cost of slow response time (>20 min). , Here, we propose a different approach consisting of maintaining the dry side of the membrane at low pressure, while continuously flushing it with dry “zero” gas. The pressure at the membrane dry side controls the total flow of dry and wet air through the membrane, and the system was designed to keep this pressure constant.…”

“…Extraction of dissolved gases from seawater was performed using a silicon rubber membrane, for which the technology has previously been described in terms of physical properties such as adsorption, permeation, and desorption. [25][26][27][28][29][30] Existing sensors, including commercial instruments from Contros (Kongsberg), Franatech, Los Gatos Research and Pro-Oceanus, employ membrane extraction for measuring dissolved gases. 31,32 Membrane extraction techniques found in the literature rely on gas equilibration across the membrane that allows for precise measurements of dissolved gas concentration, at the cost of slow response time (>20 min).…”

Evaluation of membrane-based air pre-dehumidification for a capillary radiant air conditioning system

“…The membrane transfer coefficient, K, is quite a complicated parameter related to not only the detailed membrane structure, 35 such as pore size, porosity, tortuosity and thickness of the membrane, but also the fluid parameters. 36,37 As shown in Figure 2(b) and (c), pores in the membrane wall do not exhibit uniform diameter or distribution, with finger pores mainly distributing in the inner wall of the membrane and spongy pores distributing in the outer wall of the membrane.…”

Carbon Nanotube/Brominated Poly(2,6-dimethyl-1,4-phenylene Oxide) Nanocomposite Membranes for CO2/N2Separation

“…For having advantages such as easy operations and low costs over conventional separation methods, gas separation through polymer membrane has been developing quickly in recent years [1][2][3][4][5]. Poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) has been studied as a polymeric membrane material for gas separation because of its high gas permeation.…”