5069
Ahmed Mohamed Bakr Mohamed
“Preparation and structural characterization of graphene oxide based polymer nanocomposites for waste water treatment"
graphene oxide / cellulose / chitosan / beads
The solid beads shape composites of graphene oxide (GO) and biopolymers have great potential in the efficient removal of hazardous pollutants from wastewater. In this work, graphene oxide (GO) was firstly prepared using a modified Hummers method from natural graphite powder. Graphene oxide porous crosslinked cellulose nanocomposites (GOCB) have been prepared based on GO and cellulose acetate under the conditions of pore-forming agents and latter-crosslinked with epichlorohydrin (EP). Graphene oxide crosslinked chitosan nanocomposites were prepared using Na-tripolyphosphate (TPP) as crosslinking agent. The resulting composite samples were characterized by using scanning electron microscope (SEM), Transmission electron microscope (TEM), Fourier transform infraredspectroscopy (FT-IR), X-ray diffraction (XRD), and thermal gravimetric analyses (TGA). Batch experiments were carried out for the adsorption of lead ions (Pb+2) onto prepared nanocomposites beads using atomic absorption spectroscopy and the adsorption capacities of the prepared beads were tested by varying the pH value of the solution, the initial concentration of the adsorbent and the contact time.SEM and TEM observations showed that the porous crosslinked cellulose and crosslinked chitosan nanocomposites have a relatively lower surface porosity and the addition of GO increases folding, roughness and groves that what would lead to increasing in the surface area and consequently enhancing the adsorption capacities of the composites. These applicable crosslinked beads with high porosity and spherical forms are easily swellable in water and are demonstrated as a good adsorbent due to its high surface area.
2015
Ph.d
Al-Azhar
Science