Preparation of Cross-Linked Graphene Oxide on Polyethersulfone Membrane for Pharmaceuticals and Personal Care Products Removal

Abstract

The unique two-dimensional structure and chemical properties of graphene oxide (GO) provide a convenient method for preparing novel membranes. In this study, GO membranes were prepared through filtration by a pressure-assisted self-assembly method involving the cross-linking of three diamine monomers on a polyethersulfone (PES) support. The different small molecular diamines, ethylenediamine, butanediamine, and p-phenylenediamine, were introduced as cross-linking agents to investigate the effect of diamine on the properties of GO membranes. The hydrophobic substances ibuprofen, gemfibrozil, and triclosan were selected as target pharmaceuticals and personal care products (PPCPs). The adsorption and molecular sieving activities of PPCPs by cross-linked GO membranes at a pH of 3 were investigated. The permeate water was analyzed for dissolved organic carbon, ultraviolet absorption at 254 nm, molecular weight distribution, and fluorescence excitation–emission matrices. The results showed that the removal of hydrophobic PPCPs by GO membranes was mainly due to their adsorption and molecular sieving activities. Adsorption was mainly determined by the hydrophilic and hydrophobic properties of the membranes and PPCPs. The interception effect was mainly determined by the interlayer spacing between the GO membranes and the molecular weight and steric hindrance of the PPCPs. A smaller spacing of the GO membrane layers resulted in greater steric hindrance and a higher removal rate.

Ibuprofen Removal by Graphene Oxide and Reduced Graphene Oxide Coated Polysulfone Nanofiltration Membranes

“…Although other authors have worked at different pH values, in this work the experiments were carried out under conditions of neutral pH due to the isoelectric properties of the contaminant and the membranes used. However, values of permeate flows and rejection coefficients similar to those obtained in this study can be found [34][35][36].…”

Modification of Ceramic Membranes with Carbon Compounds for Pharmaceutical Substances Removal from Water in a Filtration—Adsorption System

“…However, other reports indicate no significant improvement [ 28 ] or even deterioration of the examined properties [ 27 ]. In the papers where 100% removal of the tested PPCPs was achieved [ 29 ], different membrane techniques were used than in this study. Table 4 presents a comparison of performance of different membranes used for PPCP removal.…”

“…To this end, numerous authors modified membranes to make the membrane processes more effective for these substances. Cellulose acetate nanofiltration membranes modified by charged molecules were investigated [ 26 , 27 ] and similar modifications were made on ultrafiltration membranes made of poly(ether sulfone) [ 28 , 29 ]. Such modifications improved the separation properties of membranes in relation to many PPCPs type compounds.…”

“…Carbon compounds such as graphene, graphene oxide, reduced graphene oxide and carbon nanotubes have excellent adsorption properties [ 36 , 37 ], also for PPCP compounds [ 38 , 39 , 40 ]. The combined advantages of membrane techniques with the adsorption properties of carbon compounds helped effectively remove selected pharmaceutical compounds from water [ 29 , 41 , 42 , 43 , 44 ].…”

Graphene nanocomposites for real-time electrochemical sensing of nitric oxide in biological systems

“…Non-covalent functionalization involves the binding of molecules via supermolecular interactions, including π–π stacking and electrostatic interaction. 92 Non-covalent modification of graphene does not have any effect on its structural properties, thereby preserving inherent properties. Noble metals [such as gold (Au), silver (Ag), platinum (Pt)], metal oxides, biomolecules (hemoglobin, cytochromes), have some excellent electrocatalytic properties and graphene in combination with these nanostructures has been used to further optimize electrochemical sensing of NO.…”