Investigations for the heat treatment effects on permeability of some semi-permeable membranes

The current study aims to devise a mechanism that can regulate the permeability of semi-permeable membranes, either by enhancing or reducing it, based on their intended application. This approach seeks to offer a straightforward and efficient method for controlling membrane permeability. Cellulose acetate (CA) and cellulose triacetate (CTA) membranes were subjected to two different heat treatment processes. One method involved thermal annealing at relatively high temperatures, while the other method involved freezing the membranes when they were saturated with water. A special osmosis cell was designed and utilized to quantify the flow rates across the treated CA and CTA membranes. Our findings indicate that subjecting the membranes to high-temperature annealing decreased the flow rate. Conversely, the freezing treatment boosted the flow rate, thereby enhancing membrane permeability. This approach could pave the way for numerous applications across various fields.