Investigation Effect of Modified Graphene Oxide on The Hydrogel Properties use in Forward Osmosis Process

In recent years, one of the main important challenges faced by human societies is fulfilling the increased request for drinking water[1]. FO is a membrane-based separation process which spreads osmotic pressure gradient to be the driving force for water penetration[2]. A typical FO separation includes a feed solution, a semipermeable membrane as a separator and a solution with higher osmotic pressuere than the feed side as draw solution[3]. Due to the difference in osmotic pressure, water molecules get transferred from the feed side to the draw side, while the salt ions get rejected by the membrane[4]. One of the major challenges in the FO process is the inadequate choice of efficient draw agent. Moreover, selected draw agent is required to encounter basic criteria i.e high water penetration rate, high osmotic pressure, and suitable with membrane surface[5]. Recently, scientists are concentrating on polymer hydrogels as a draw agent in the FO process[6]. Polymer hydrogels due to the developed high osmotic pressure can prepare an adequate driving force to draw water from high salinity seawater across the membrane. Cross-linked polymer chains that are composed of three-dimensional network structures is the characteristic of polymer hydrogels[7]. ammonium, carboxyl, and sulphonic acid) in the structure of polymer hydrogel, is the reason why polymer hydrogels absorb a large amount of water[4]. The attendance and dissociation of various ionic species in the polymer hydrogel are the cause to swelling and higher internal osmotic pressure creation.In this study,first grapheme oxide was modified with silane[3-Trimethoxysilyl propyl methacrylate](EGO),this material was used as a crosslinker agent for the preparation of hydrogel.The nanoparticles were then used to modified the acrylic acid(AA) and acrylamide(AAm) hydrogel properties in the forward osmosis processS.ubsequently,It was evaluated by XRD,FTIR,TGA and scanning electron microscopy tests.The result of the swelling test showed that the nanocomposite hydrogel obtained whit a more polar functional groups,more porous structure,have higher swelling and water absorption capacity than the pure polymer hydrogel.The EGO hydrogel also has significantly higher water flux than the pure polymer hydrogel.