Material BehaviourRemoval of benzene from aqueous solution by adsorption using PDMS membrane devices

Polydimethylsiloxane (PDMS)-coated devices were employed to remove benzene from an aqueous solution in a batch reactor. Because of significant swelling of the PDMS membrane, the diffusion of benzene in PDMS exhibited pseudo-Fickian behavior. Based on the solution-diffusion model, the diffusion, solubility and permeation coefficients of benzene in PDMS membrane were obtained and found to be dependent on the benzene concentration of the aqueous solution. The sorption isotherm of benzene solution in PDMS membrane was of the Freundlich type and similar to linear partition. A mass transfer model provided good simulations of the results of aqueous benzene sorbed by the PDMS-coated Tellerette packing using the permeability obtained by the separate sorption experiments. The PDMS extraction technique can be applied to remove benzene from industrial wastewater, especially for lower concentrations.