Search

Novel low-cost cellulose triacetate-based membranes extracted from palm fronds have been fabricated through the phase–inversion procedure. The cellulose tri-acetate (CTA) membrane was modified by incorporation of graphene oxide (GO) prepared from palm fronds according to the modified Hummer method as well as the preparation of polyamide thin film composite CTA membranes to improve forward osmosis performance for seawater desalination. The surface characteristics and morphology of the prepared CTA, GO, and the fabricated membranes were investigated. The modified TFC prepared membrane had superior mechanical characteristics as well as permeation of water. The performance of the prepared membranes was tested using synthetic 2 M Sodium chloride (NaCl) feed solution. The water flux (Jw) of the thin-film composite (TFC) (CTA/0.3% GO) was 35 L/m2h, which is much higher than those of pure CTA and CTA/0.3% GO. Meanwhile, the salt reverse flux TFC (CTA/0.3% GO) was 1.1 g/m2h), which is much lower than those of pure CTA and CTA/0.3%. GO (Specific salt flux of TFC (CTA/0.3% GO) substrate membrane was 0.03 g/L indicating good water permeation and low reverse salt flux of the TFC membrane compared to CTA. A real saline water sample collected from Hurgada, Egypt, with totally dissolved solids of 42,643 mg/L with NaCl as the draw solution (DS) at 25 °C and flow rate 1.55 L/min, was used to demonstrate the high performance of the prepared TFC membrane. The chemical analysis of desalted permeated water sample revealed the high performance of the prepared TFC membrane. Consequently, the prepared low-cost forward osmosis (FO) thin-film composite CTA membranes can be introduced in the desalination industry to overcome the high cost of reverse osmosis membrane usage in water desalination.

A series of polyethersulfone membranes containing Ag@HPEI@GO composite was fabricated using non-solvent induced phase separations (NIPS) to mitigate against biofilm causing bacteria and modulate solute rejection. All materials produced and used were fully characterised using a combination of appropriate physicochemical techniques including FTIR, XRD, BET, SEM, AFM. The GO-based fillers exhibited bactericidal activities. The bactericidal activities of GO, HPEI@GO against

The high concentration of sulphates is detrimental to the infrastructure of wastewater treatment plants. Hence in this study, we present the application of electrocoagulation sludge as an adsorbent to remove sulphates from industrial effluents before they are released back to the environment. The sludge contains iron and aluminium cations and cationic complexes that precipitate sulphates in water. Corrugated iron sheet was used as a sacrificial electrode during electrocoagulation (EC) to generate sludge. FTIR, XRD, SEM, TEM, and Zeta Potential were used to characterize the sludge. The following parameters: contact time, pH, initial concentration, and adsorbent dosage were optimized to 120 min, 2, 100 mg/L and 150 mg, respectively. For the synthetic water, the sulphate removal was 99.1%, whereas for the real water it was found to be 98.7%. The adsorption capacity of the EC sludge was 66.76% for 2 h under acidic conditions. The Langmuir isotherm fitted better than the Freundlich isotherm. This confirmed the homogenous distribution of the active sites on the EC sludge. At different EC’s sludge, the pseudo-second order kinetic model produced the best fitting experimental results which confirmed the removal of sulphate ions by chemisorption. This approach (method) is useful for purifying industrial effluents before they are discharged into the environment.

Fabrication of the ZSM-22/Polyethersulfone (ZSM-22/PES) membranes as selective salt filters represent a growing membrane technological area in separation with the potential of high economic reward based on its low energy requirements. The incorporation of ZSM-22 zeolite material as additives into the PES polymer matrix has the prospective advantage of combining both the zeolite and polymer features while overcoming the limitations associated with both materials. This work investigated the influence of the nature of the silica precursor on ZSM-22 zeolite hydrothermally synthesised using colloidal (C60) and fumed (C60) silica to Si/Al of 60. The successful synthesis of the highly crystalline zeolitic materials was confirmed through XRD, FTIR, and SEM with EDX. The ZSM-22 additives were directly dispersed into a PES polymeric matrix to form a casting solution for the preparation of the ZSM-22/PES selective substrate layers via a phase inversion method for salts rejection. The polymeric PES was selected as an organic network in which the content of the ZSM-22 zeolite (ranging between 0 and 1.0 wt.%), was obtained and characterised by XRD, FTIR, and SEM analysis, as well as water contact angle (WCA) measurement and dead-end filtration cell. The phase inversion preparation method has induced the resulting ZSM-22/PES NF substrates anisotropy, as attributed to a high water flux to the above 700 L·m−2·h−1; high selectivity and rejection of salts to above 80% is revealed by the obtained results. The materials also exhibited improved antifouling behavior to above 70% flux recovery ratios. As such, the nature of the silica precursor influences ZSM-22 zeolite synthesis as a potential additive in the PES polymer matrix and led to the enhanced performance of the pure PES ultrafiltration membrane.