Polydimethylsiloxane (PDMS) Membrane for Separation of Soluble Toluene by Pervaporation Process

Abstract

A commercial polydimethylsiloxane (PDMS) membrane was employed to separate the soluble toluene compounds (C7H8) from an aqueous solution via the pervaporation (PV) process. The performance and the efficacy of the PDMS PV membrane were evaluated through the estimation of the permeation flux and separation factor under various operating parameters. The response surface method (RSM) built in the Minitab-18 software was used for the design of the experiment in this study, and the responses of the permeation flux and the separation factor were analyzed and optimized based on the operating conditions. A nonlinear regression analysis was applied to the experimental output and input, and as a result, a quadratic equation model with parameters interactions was obtained as mathematical expressions to predict the permeation flux and separation factor. At the optimal conditions of temperature 30 °C, initial toluene concentration 500 ppm, and feed flowrate 3.5 L/min, the toluene permeation flux and separation factor were 125.855 g/m2·h and 1080, respectively. The feed concentration was the most impactful and significant in the improvement of the permeation flux and separation factor of the PDMS membrane.

An empirical investigation and computational modeling of volatile organic compound (VOCs) elimination from aqueous solutions by means of Pervaporation

“…where 𝐷𝐷 𝐵𝐵 and 𝐷𝐷 𝑤𝑤 are the diffusivity of benzene and water, respectively, 𝑎𝑎 𝐵𝐵,𝑓𝑓 is the activity of benzene in feed, and β B and β w are the plasticization parameters for benzene and water respectively, which depend on the temperature and the benzene concentration and were calculated and presented in Table (1). The parameters A1, A2, A3, and A4 correspond to the benzene and water constituents.…”

“…The experimental arrangement employed for evaluating the pervaporation process was previously detailed in our earlier publication [44]. To summarize, an initial feed solution of 1.5L comprised a toluene-water mixture.…”

“…Besides preserving the environment from pollution by volatile organic compounds (VOCs) and protecting river water and aquatic life, these materials must be disposed of using modern, more effective, less costly methods. Many industrial applications use organic solvents in their technological processes to have products such as refrigerants, plastics, adhesives, paints, and petroleum products [1]. Pervaporation constitutes a separation technique wherein a semi-permeable membrane is employed to selectively extract components, predominantly volatile substances, from a liquid mixture.…”