Madineh Sadeghipour; Mehdi Kheirmand; Azar Asadi
Abstract
This research focused on improving the antifouling properties and rejection performance of polyetherimide (PEI) nanofiltration membrane by chemical surface modification (surface coating). The hydrophilicity of the PEI nanofiltration membrane’s surface was enhanced by anchoring guanidine on its ...
Read More
This research focused on improving the antifouling properties and rejection performance of polyetherimide (PEI) nanofiltration membrane by chemical surface modification (surface coating). The hydrophilicity of the PEI nanofiltration membrane’s surface was enhanced by anchoring guanidine on its surface which the used dosage of guanidine wasconsidered as a variable (0.5, 1, and 1.5 g/L of guanidine concentration). ATR-FTIR, SEM, AFM, and water contact angle were used to characterize the surface-modified membranes. Also, dry milk powder solution was considered as an organic foulant to assess antifouling features of the fabricated membranes. According to the obtained results, the surface modified membrane with 0.5 g/L of guanidine concentration was the optimal surface-modified membrane with pure water flux (PWF) and flux recovery ratio (FRR) of 11.6 kg/m2.h and 88.8%, respectively. Moreover, the capabilities of the optimal surface-modified membrane and the pristine membrane for rejecting AS5+ and Hg2+ in aqueous solution with concentrations of 20 ppm and 50 mg/L were compared. Based on the obtained results, the optimal surface-modified membrane rejected more than 98.5 % of AS5+ and Hg2+ solutions with 20 and 50 mg/L of metal ion concentrations.
Farinaz Ahmadi; Ali Akbar Zinatizadeh; Azar Asadi
Abstract
In this research, the possibility of polyhydroxyalkanoates (PHAs) production in a mixed microbial culture fed by industrial soft drink wastewater was assessed. To enrich the microbial culture, an uncoupled carbon and nitrogen feeding strategy were used in sequencing batch bioreactor (SBR). To evaluate ...
Read More
In this research, the possibility of polyhydroxyalkanoates (PHAs) production in a mixed microbial culture fed by industrial soft drink wastewater was assessed. To enrich the microbial culture, an uncoupled carbon and nitrogen feeding strategy were used in sequencing batch bioreactor (SBR). To evaluate the efficiency of the strategy, PHA, substrate, dissolved oxygen, biomass and nitrogen concentration profiles were reported in the 16th cycles of the SBR. From the obtained data, COD and nitrogen removal efficiencies were 89 % and 75.5 %, respectively at the cycle time of 12h. Also, the maximum poly-hydroxybutyric acid (PHB) content and specific PHA production rate (qp) were achieved as 13.8% (mg-PHB/mg-TSS) and 6.4×10-3 (mg COD-PHA/mg COD-X.h), respectively.
