Abstract
Abstract : Membrane technology has emerged as a viable means of water purification with advantages such as low cost, energy efficient, high removal efficiency and environmentally friendly production. The membrane that is considered ideal should provide improved stability, higher selectivity, higher flux, and resistance to chlorine and fouling. However fouling, low hydrophilicity and low flux remain challenges facing this technology. In this study Polyethersulfone (PES) membrane was used as a support for thin film composite membrane (TFC) and was adjusted by controlling fabrication processes, which are commonly recognized by adding additives that includes organic and inorganic materials and also by altering controlling fabrication parameters. Zeolitic imidazolate framework-8 @ graphene oxide (ZIF-8@GO) composites at different concentrations (0.1, 0.5, 0.9 and1):1 were synthesized and characterized using SEM, TEM, XRD, BET, TGA, FTIR and Raman instruments before they were embedded on top thin layer of polyamide-thin film composite (PA-TFC) membranes. PA-TFC membranes were prepared successfully using m-Phenylenediamine (MPD) and trimesoyl chloride (TMC) as monomers whereby composites (GO, ZIF-8, ZIF-8@GO) were dispersed into aqueous solution of MPD over PES support layer via interfacial polymerization process. Thereafter the surface morphology, cross section and surface roughness were characterized using SEM and AFM microscopes before reverse osmosis application. The membranes incorporated with composites resulted in lower surface roughness, higher fluxes, higher salt and dye rejection as compared to the pure PES. In addition membranes with lower surface roughness displayed a better fouling propensity than pristine PES and TFC membranes.
M.Sc. (Nanoscience)