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Acrylonitrile-butadiene-styrene (ABS)/high impact polystyrene (HIPS) blend heterogeneous anion exchange membranes were prepared by phase inversion method using tetrahydrofuran as solvent and anion exchange resin powder as functional group agent. Activated carbon was selected as inorganic filler additive. The additive concentration effect on properties of the prepared membranes was studied. Ultrasonic method was used to help appropriate dispersion of particles in the membrane's matrix. Scanning optical microscopy showed that sonication has a significant influence on distribution of resin particles in the membrane matrix and makes it possible to form more uniform phase. Moreover, images showed a relatively uniform surface for membranes. The increase of activated carbon concentration in casting solution led to a decline in membrane water content. The ion exchange capacity, membrane potential, permselectivity, transport number, ion permeability, ionic flux, and current efficiency of prepared membranes all were increased initially by the increase in additive concentration up to 1% wt and then they showed decrease trend with higher increase in additive concentration from 1 to 4% wt. Conversely, the electrical resistance and energy consumption showed opposite trends. In addition, with more additive loading, the oxidative stability of membranes was slightly decreased and their thermal stability was increased. Membrane with 1% wt additive loading exhibited higher efficiency and electrochemical properties in comparison with other prepared membranes in this research. Furthermore, prepared membranes exhibited suitable electrochemical properties compared to a commercial heterogeneous anion exchange membrane with the same experimental conditions.

Produced water or oilfield wastewater is the largest volume ofa waste stream associated with oil and gas production. The aim of this study was to investigate the biological pretreatment of synthetic and real produced water in a sequencing batch reactor (SBR) to remove hydrocarbon compounds. The SBR was inoculated with isolated tropical halophilic microorganisms capable of degrading crude oil. A total sequence of 24 h (60 min filling phase; 21 h aeration; 60 min settling and 60 min decant phase) was employed and studied. Synthetic produced water was treated with various organic loading rates (OLR) (0.9 kg COD m(-3) d(-1), 1.8 kg COD m(-3) d(-1) and 3.6 kg COD m(-3) d(-1)) and different total dissolved solids (TDS) concentration (35,000 mg L(-1), 100,000 mg L(-1), 150,000 mg L(-1), 200,000 mg L(-1) and 250,000 mg L(-1)). It was found that with an OLR of 0.9 kg COD m(-3) d(-1) and 1.8 kg COD m(-3) d(-1), average oil and grease (O&G) concentrations in the effluent were 7 mg L(-1) and 12 mg L(-1), respectively. At TDS concentration of 35,000 mg L(-1) and at an OLR of 1.8 kg COD m(-3)d(-1), COD and O&G removal efficiencies were more than 90%. However, with increase in salt content to 250,000 mg L(-1), COD and O&G removal efficiencies decreased to 74% and 63%, respectively. The results of biological treatment of real produced water showed that the removal rates of the main pollutants of wastewater, such as COD, TOC and O&G, were above 81%, 83%, and 85%, respectively.