Evaluation of the transport Parameters and physiochemical properties of forward osmosis Membranes after treatment of produced water, Journal of Membrane Science, http://dx. AbstractThe application of semipermeable membranes for dewatering of complex oil and gas wastewaters continues to be a topic of increasing interest. Several studies have explored the fouling propensity and contaminant rejection of osmotically driven membranes during forward osmosis (FO) treatment of produced waters; however, none have investigated changes in membrane transport and physiochemical properties after exposure to these feed streams. In this study we discuss the impacts of produced water exposure on the transport and active layer surface properties of cellulose triacetate (CTA) and polyamide thin-film composite (TFC) FO membranes. While produced water exposure yields some, albeit minor, changes to the membrane performance and surface characteristics of the CTA and the traditional TFC membranes, close to 50% reduction in reverse salt flux and contaminant transport was observed for a surface-modified TFC FO membrane; only minimal changes in water permeability were recorded. Results of this study demonstrate the chemical and physical robustness of FO membranes for treatment of oil and gas wastewaters, and they highlight a knowledge gap that exists in membrane polymer selection and contaminant interactions with the membrane polymer matrix that should be further addressed in future membrane fouling studies.

The pores of microfiltration polyethersulfone membranes have been functionalized with homopolymer and block copolymer grafts through sequential cationic polymerization of styrene and substituted styrene monomers, namely 4-chloromethylstyrene and 4-ethoxystyrene.1 H NMR characterization confirmed successful incorporation of polymeric grafts at different stages of functionalization. The functionalized membrane showed a 90% decrease in membrane permeability compared to the raw membrane indicating the presence of polymeric chains in the membrane flow path. Functionalized membranes have as many as 125 repeat units per chain equating to an ion-exchange capacity (IEC) of 4.9 meq/g, representing 92% of the theoretical IEC of an ion-exchange resin. A pseudo-first-order kinetic equation correlated well (R 2 $ 0.99) with the experimental kinetic data of formation of polymeric grafts.Polymer growth studies showed that at lower initiator surface density (initiator contact time <135 min), graft length and IEC were impacted by monomer feed concentration and initiator contact time.