Synthesis and performance of thin film composite nanofiltration polyester membrane for removal of natural organic matter substances

Nanofiltration (NF) polyester thin-film composite (TFC) membranes have been prepared by interfacial polymerization using commercial polyethersulfone membrane support. At 6% (w/v) triethanolamine (TEAO) concentrations in the aqueous solution and a range of interfacial polymerization times in the organic solution containing trimesoyl chloride (TMC) were studied. Nanofiltration membranes were produced with varying properties through interfacial polymerization technique. The ability to use NF membranes with varying properties will improve overall process efficiency. This study has shown that through interfacial polymerization technique, the variation of reaction time as well as can affect the performance of the membrane produced. As a result, increasing the reaction time resulted in decreasing water permeabilities. Polyester with some amide group produced after interfacial polymerization occurred as shown by FT-IR spectra. Straight lines were obtained between Jw and ΔP and the water flux of distilled water shown that flux is directly proportional to transmembrane pressure (TMP). At low reaction time (5 min), the water flux has no significant effect on water permeance. So, the reaction time has a significant effect on the growth of thin film

Investigation of New Polyester Nanofiltration (NF) Membrane Fouling with Humic Acid Solution

Ultrafiltration (UF) polyethersulfone membrane support has been modified by interfacial polymerization technique using reaction of aqueous solution and organic solution to form thin film composite (TFC) nanofiltration (NF) membrane. A new polyester layer were produced on the top surface of UF support by the reaction between triethanolamine (TEOA) (6% w/v) in the aqueous solution and solution containing trimesoyl chloride (TMC) (0.15%w/v) at different of reaction times (15, 25 and 35 min). The decrease of membrane permeability was related to the changes of the membrane morphology (i.e. membrane thickness) as the reaction times were increased. Irreversible membrane fouling has been studied by using humic acid as model of natural organic matter (NOM) solutions at two different pH values (7 and 3). At pH 7, it was observed that the NF TFC membranes exhibited practically less tendency to be irreversibly fouled by humic acid. However, the permeate flux was decreased and the irreversible fouling factor was increased with decreasing the pH to a value of 3