Synthesis and Characterization of Tfc Membranes for Water Reuse
Byeong-Heong Jeong, Asim K. Ghosh, Xiaofei Huang, and Eric M. V. Hoek. Civil & Environmental Engineering, UCLA Water Technology Research Center and California NanoSystems Institute, Henry Samueli School of Engineering and Applied Science, 5732G Boelter Hall, University of California, Los Angeles, Los Angeles, CA 90095
Thin film composite (TFC) membranes have been synthesized on various polysulfone ultrafiltration support membranes through an interfacial polymerization reaction with the intent of improving membrane performance. The impacts of support membrane structure, in addition to organic solvents (hexane, cyclohexane, heptane, and isoparaffin) and reaction solution additives on the structure, morphology, and performance of polyamide thin film composite membranes was evaluated. The structure and morphology of formed membranes was characterized by various macroscopic (contact angle and streaming potential), microscopic (SEM/TEM/AFM), and spectroscopic (EDX/ATR-IR) analytical techniques. The separation performance of synthesized membranes was characterized by permeation tests using pure water and 2,000 ppm solutions of NaCl, MgSO4, and polyethylene glycol. Membranes formed on all support membrane structures possess similar hydrophilicity, smoothness, and surface charge density, while exhibiting varied water permeability and solute rejection. Alternatively, membranes formed with different organic solvents and inorganic/organic additives can exhibit varied hydrophilicity, smoothness, and surface charge density, in addition to varied water permeability and solute rejection. We will demonstrate how different support membrane structures and reaction chemistries produce polyamide TFC membranes with widely varying performance properties. In particular, we will discuss different synthesis routes to obtain novel, low energy and fouling resistant membranes for water reuse.