Cellulose acetate (CA) is a semisynthetic, biodegradable polymer. Due to its characteristics, CA has several applications, including water membranes, filament-forming matrices, biomedical nanocomposites, household tools, and photographic films. This review deals with topics related to the CA membranes, which are prepared using different techniques, such as the phase inversion technique. CA membranes are considered very important since they can be used as microfiltration membranes (MF), ultrafiltration membranes (UF), nanofiltration membranes (NF), reverse osmosis (RO) membranes, and forward osmosis (FO) membranes. Membrane fouling results from the accumulation of materials that the membrane rejects on the surface or in the membrane’s pores, lowering the membrane’s flux and rejection rates. There are various forms of CA membrane fouling, for instance, organic, inorganic, particulate fouling, and biofouling. In this review, strategies used for CA membrane antifouling are discussed and summarized into four main techniques: feed solution pretreatment, cleaning of the membrane surface, membrane surface modification, which can be applied using either nanoparticles, polymer reactions, surface grafting, or surface topography, and surface coating.

Silver nanoparticles (AgNPs) were successfully synthesized using the aqueous extract of the Paronychia argentea Lam (P. argentea) wild plant. The results showed that the conversion of Ag⁺ to Ag⁰ nanoparticles ratio reached 96.5% as determined by Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES), with a negative zeta potential (ζ) of −21.3 ± 7.68 mV of AgNPs expected to improve the stability of synthesized AgNPs. AgNP antibacterial activity has been examined against Streptococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria. The minimum inhibition concentration (MIC) was 4.9 µL/mL for both E. coli and S. aureus bacteria, while the minimum bactericidal concentrations (MBC) were 19.9 µL/mL and 4.9 µL/mL for S. aureus and E. coli, respectively. The synthesized AgNPs were incorporated in ultrafiltration polyvinylidene Fluoride (PVDF) membranes and showed remarkable antibiofouling behavior against both bacterial strains. The membranes were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and X-ray diffraction (XRD). The contact angle and porosity of the membrane were also determined. The efficiency of the membranes regarding rejection rate was assessed using bovine serum albumin (BSA). It was found in the flux experiments that membranes BSA rejection was 99.4% and 98.7% with and without AgNPs, respectively.

Fluorite-type Zr-based oxides with the composition Ga₂Zr_2−xW_xO₇(x= 0, 0.05, 0.1, 0.15 and 0.2) were prepared using the citrate technique. Appropriate characterizations of all prepared materials were carried out. X-ray diffraction clarified that the undoped and W-doped Ga₂Zr₂O₇samples were crystallized in the cubic fluorite phase structure. The average particle size of the samples was in the range of 3–8 nm. The lowest band gap (1.7 eV) and the highest surface area (124.3 m²g⁻¹) were recorded for Ga₂Zr_0.85W_0.15O_7.The photocatalytic impacts of the prepared systems were studied by removal of crystal violet (CV) dye employing visible light illumination and taking into consideration the initial dye concentrations, duration of visible irradiation treatment, catalysts dose and the dopant concentration. The obtained results showed higher dye removal with the boost of the catalyst dosage. W doping shifted the absorption to the visible light range by decreasing the band gap from 4.95 eV for parent Ga₂Zr₂O₇to 1.7 eV for 15 mol% tungsten-doped Ga₂Zr₂O₇enhancing the photocatalytic decolourization of CV from 4.2% to 83.6% for undoped and 15 mol% W-doped Ga₂Zr₂O₇, respectively, at optimum operating conditions (pH 9, 1 g l⁻¹catalyst dose and 300 min) while heavily doped W sample containing 20 mol% W showed lower removal than 15 mol% W-doped Ga₂Zr₂O₇. Complete CV degradation using 15 mol% W-doped Ga₂Zr₂O₇was attained with the assistance of 25 mmol l⁻¹hydrogen peroxide. The reaction is aligned to pseudo-first-order kinetics. Different scavengers were introduced to decide the significance of the reactive species in CV degradation.O2−∙and h⁺had the major role in the degradation of CV by Ga₂Zr_2−xW_xO₇system compared with HO^•.