Improving 1H-benzotriazole Removal from Aqueous Solutions by Polymer Inclusion Membranes by the Addition of Reduced Graphene Oxide and the Application of Ultrasound

This study investigates the application of polymer inclusion membranes (PIMs) for the removal/recovery of 1H-benzotriazole from aqueous solutions, via facilitated transport mechanism, using tri-n-octylamine as a carrier and NaOH as a stripping agent. The process efficiency was analyzed using 1H-benzotriazole flux and permeability through the membrane, its recovery percentage, and the transport process kinetic constant. PIM containing 40% cellulose triacetate, 30% o-nitrophenyl octyl ether and 30% tri-n-octylamine yielded the best results for all four parameters studied due to the role of o-nitrophenyl octyl ether and tri-n-octylamine in reducing the cellulose triacetate polarity, which leads to carrier solubilization on the plasticizer, creating continuous pathways within the membrane and facilitating 1H-benzotriazole transport. Reduced graphene oxide inclusion as the fourth PIM component increases its hydrophobicity, promoting continuous pathway formation and enhancing 1H-benzotriazole transport, which leads to an increase of 10% to 20% in the values of the four parameters analyzed. Ultrasound use in membrane preparation leads to a further increase of 9% to 20% in the values of the four parameters analyzed because the cavitation effect improves the molecular mixing of membrane components and results in a less ordered configuration of cellulose triacetate molecules, thereby reducing their crystallinity degree. All of this significantly improves the interaction between the membrane components and pathway formation, enhancing 1H-benzotriazole transport through the membrane.