Afsaneh Shahbazi

A novel high-flux polyethersulfone (PES)-based nanofiltration (NF) membrane was developed by embedding amino-functionalized N-doped hollow porous carbon spheres (N-HPCS/NH₂) for efficient treatment of beverage-industrial wastewater. The N-HPCS/NH₂ nanofiller was synthesized via a hard-templating method and surface-functionalized using 3-aminopropyltriethoxysilane (APTES). The modified nanofiller exhibited a porous hollow structure with a high specific surface area (630.24 m²/g) and abundant amino groups, contributing to improved hydrophilicity and pollutant adsorption. The incorporation of low concentrations (0.1 wt%) of N-HPCS/NH₂ into the PES matrix resulted in membranes (M1) with superior structural, mechanical, and surface charge characteristics. Compared to the bare membrane, M1 exhibited a ~ 4.5-fold increase in pure water flux (230 L/m²·h), enhanced anti-fouling properties (FRR > 90%), and significantly higher removal efficiencies for salts (up to 84.6% for Na₂SO₄), dyes (> 99% for RR195, MB, RhB), and heavy metals (up to 99.81% for Pb²⁺). The efficiency of the M1 membrane was also studied in a salt-dye binary filtration system containing Na₂SO₄ at different concentrations (100–5000 ppm) and 200 ppm RR195. It was observed that increasing Na₂SO₄ concentration reduced RR195 removal slightly from 99.82% to 98.8%, suggesting minor interference due to ionic shielding. The membrane performance remained stable under continuous operation for 72 h and showed negligible decline in real beverage-industry wastewater treatment. The synergistic effects of enhanced hydrophilicity, surface charge, and active adsorption sites enabled the M1 membrane to achieve both high permeability and selectivity. These results demonstrate the potential of PES/N-HPCS/NH₂ membranes as robust candidates for sustainable industrial wastewater treatment. Graphical abstract The alternative text for this image may have been generated using AI.

A new rhodamine-B carbonyl-morpholine derivative (denoted as RECM) was prepared by a two-step synthesis procedure. The employed method allowed a lactam ring development of rhodamine-B and ethylenediamine to demonstrate a facile amide bond formation. The obtained RECM was confirmed by ¹H NMR, ¹³C NMR, and mass spectrometry analysis. RECM was formed to detect copper ion (Cu²⁺) due to its problematic toxicity features in aquatic ecosystems. It showed a high selectivity toward Cu²⁺ in comparison with some environmentally relevant alkali, alkaline earth, and transition metal cations at 50 µM in acetonitrile. Moreover, non-fluorescent RECM showed fluorescence intensity and UV-Vis absorbance increases in the presence of Cu²⁺ with high linear dependent coefficients (R² = 0.964 and R² = 0.982 respectively) as well as a color change from colorless to pink owing to the ring opening of the rhodamine spirolactam form. Binding capability experiments presented a clear 1:1 stoichiometry of RECM–Cu²⁺ complex with the binding constant (K_a) as 2.25 × 10⁴ M⁻¹. The calculation of limits of detection (LOD) was 0.21 µM based on the linear regression method, which is below the maximum contaminant level goal (MCLG) value of Cu²⁺ (1.3 ppm equals to 20.46 µM) in drinking water. These characteristics make the RECM a promising candidate for the real-time detection of toxic Cu²⁺ in environmental monitoring applications.