Solvent-Resistant Thin-Film-Composite Poly(methyl)siloxane Nanofiltration Membranes for a Soybean Oil Extraction Process

An economical membrane-based nonthermal methodology is required for industrial adoption in order to address the high energy consumption and environmental impacts of conventional thermal methods in vegetable oil extraction plants. To facilitate faster solvent recovery during soybean oil extraction, we created a thin-film-composite (TFC) oil barrier with high hexane permeability using a poly(methyl)siloxane (PMS) cross-linked nanofiltration membrane. Our strategy was to apply a thin hydrophobic PMS layer just to the surface of a hydrophilic, porous polyacrylonitrile-co-methacrylic acid (PANMA) sublayer supported by nonwoven, reinforced polyester fabric. An unprecedented productivity of the permeance of miscella up to 225 L·m–2·h–1·MPa–1 with acceptable oil rejection selectivity was demonstrated by the membranes used in the hexane (solvent) extraction of 20% model hexane–soybean (called miscella). This is a significant step toward a sustainable solvent extraction solution.