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BACKGROUND: Microbial desalination cell (MDC) is a new technology in the use of electrical energy for water desalination and wastewater treatment. RESULTS: Open circuit (OC) and closed circuit (CC) modes were successfully simulated with initial TDS concentrations of 10 g/L and 10–15 g/L, respectively (an external resistance of only 150 Ω was applied for CC). After 160 h of operation, the maximum OC voltage, desalination efficiency and COD removal efficiency were 809 mV, 32.2% and 79.2%, respectively. The maximum voltage was also obtained when the external resistances were 150 Ω (423.4 and 438 mV) for the initial NaCl concentrations (10 and 15 g/L) in the central chamber, respectively. Moreover, the maximal desalting and COD removal efficiencies after 24 h run‐time were (30% and 28%) and (24% and 25%) for initial NaCl concentrations (10 or 15 g/L) in the central chamber, respectively. Maintaining pH (8.61, 7.01) to (7.85, 7.8) in anode and cathode chambers was studied. This research accurately depicted microbial desalination's efficiency in generating OC voltages and CC electrical energy via Box–Behnken Design Distribution (BBD). Investigated factors' interactions (initial salt/COD concentrations, time) on CC system's energy efficiency. Resulted in peak productivity at (1.85 mW), OC reaching (1100 mV). CONCLUSION: Finally, the research paper gave exciting results in improving the efficiency of the microbial desalination cell to increase the ability to produce electrical energy and desalinate water. © 2023 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

The present study utilised date palm fibre (DPF) waste residues to adsorb Congo red (CR) dye from aqueous solutions. The features of the adsorbent, such as its surface shape, pore size, and chemical properties, were assessed with X-ray diffraction (XRD), BET, Fourier-transform infrared (FTIR), X-ray fluorescence (XRF), and field emission scanning electron microscope (FESEM). The current study employed the batch system to investigate the ideal pH to adsorb the CR dye and found that acidic pH decolourised the dye best. Extending the dye-DPF waste mixing period at 25 °C reportedly removed more dye. Consequently, the influence of the starting dye and DPF waste quantity on dye removal was explored in this study. At 5 g/L dye concentration, 48% dye removal was achieved, whereas at low dye concentrations, only 40% of the dye was removed. The current study also evaluated the DPF particle size created for dye adsorption, yielding a 66% optimal powder size removal. The heat impact assessment performed in this study indicated that increased temperature affected the amount of dye eliminated from aqueous solutions, where a 72% removal was recorded at 45 °C. The pseudo-first- and pseudo-second-order models were utilised to predict the maximum CR dye adsorption with DPF waste. Resultantly, the Langmuir-Freundlich experimental DPF waste CR adsorption documented pseudo-second-order kinetics. In a fixed bed reactor, the DPF waste has been reported to remove CR dye constantly. Consequently, several factors affecting the removal process, including the effects of primary dye, the flow rate of the liquid inside the column, the depth of the filling inside the column, and flow rate were assessed. The results were simulated in the COMSOL® program and compared to practical experiments, which yielded a 99% match. Conclusively, DPF waste could remove several colours from wastewater via active removal. [ABSTRACT FROM AUTHOR]

Current work aimed to optimize the electrocoagulation (EC) process for the efficient and economic removal of ciprofloxacin (CIP) and levofloxacin (LVX) from aqueous solution via response surface methodology. Four main parameters were selected for the optimisation process, including the initial pH of the solution, initial concentration of antibiotics, operation time, and current density. Subsequently, kinetic and isotherm modelling was performed to characterise the performance behaviour of the EC process at optimum conditions. Based on the results, the EC process achieved a removal efficiency of 92% and 84% for CIP and LVX, respectively, under optimum experimental conditions. The experimental results were consistent with the Langmuir isotherm model for the adsorption of both antibiotics on the iron hydroxide (Fe(OH)3) flocs based on the predicted maximum adsorption capacity of 142 and 185 mg/g, respectively. In addition, the experimental results best fitted the second-order kinetic model with a coefficient of determination (R²) value of 0.986 and 0.992 for CIP and LVX, respectively, implying the chemisorption mechanism controlling the adsorption process. The regression analysis also showed that the experimental results best fitted with the second-order polynomial model with a predicted correlation coefficient (Pred. R²), adjusted correlation coefficient (Adj. R²), and R² of 0.834, 0.941, and 0.967 for CIP; 0.723, 0.908, and 0.952 for LVX, respectively. In short, a comprehensive economic evaluation was performed and the total operational cost over a single run under optimized EC conditions was estimated at $0.490 US/m3. Under optimized EC conditions, the electrical energy consumption and electrode consumption were 3 kWh/m3 and 0.167 kg/m3, respectively, during a single run. [ABSTRACT FROM AUTHOR]