Algeria faces severe water stress, marked by a decrease in water availability per inhabitant from 1,500 m ³ /year in 1962 to 430 m ³ in 2020, with a projection of 300 m ³ by 2050. In this context, optimizing wastewater treatment plants (WWTPs) becomes essential to reduce the water deficit. This study evaluates the performance of the urban wastewater treatment plant of Maghnia (Northwestern Algeria) by carrying out a statistical analysis of physicochemical parameters and comparing the Weighted Arithmetic Water Quality Index (WAWQI) and Water Pollution Index (WPI) based on data collected between January 7, 2020, and March 22, 2021. Reliable detection of outliers was achieved through the combined application of Grubbs and Tukey tests, while data normality was verified by Shapiro–Wilk, Anderson–Darling, and the P-P plot, thus strengthening analytical robustness and minimizing bias. The results show stability of physical parameters (temperature and pH) and moderate variability of chemical parameters, including chemical oxygen demand (COD), total suspended solids (TSS), and biochemical oxygen demand (BOD₅), at the plant inlet. However, notable exceedances of standards at the outlet were observed, notably for ammonium (7.92 mg/l, standard limit: 5 mg/l) and phosphates (10.01 mg/l, standard limit: 2 mg/l), indicating deficiencies in biological treatment despite high organic matter removal efficiency. Bland–Altman analysis confirms the complementarity of the WAWQI and WPI indices, highlighting low quality of treated water and chronic system overload. These results underscore the need for targeted process optimization, particularly for nutrient removal, to ensure safe reuse of treated wastewater.

In this paper, an extraction procedure carried out in a closed reactor, for mercury (II) present in an aqueous media using Chelex 100 resin, was applied to develop a mathematical model and optimize process parameters for Hg(II) removal. The optimization process was carried out using 2⁴ factorial designs. The individual and combined effect of four process parameters, i.e. initial pH of the solution (1.6 and 7.0), initial Hg(II) concentration (10⁻⁵ and 10⁻³ mol/L), mass of sodium chloride (0.10 and 73 mg), and resin mass on Hg adsorption (0.05 and 0.2 g), were studied. Analysis of variance showed the relative importance of process parameters in the removal procedure. The optimal conditions to remove Hg from the aqueous solution, at the constant temperature of 20°C and stirring speed of 1,000 rpm were found to be: contact time = 3 h, pH 7, initial Hg(II) concentration = 1 mmol/L, ionic strength = 10⁻⁴ g, and resin dosage = 0.2 g. Under these conditions, high removal efficiency (98.0%) was achieved. Student’s t-test on the results of the 2⁴ factorial designs, with 16 runs for mercury extraction, showed that the factor “ionic strength value” in the studied levels is statistically significant. The authors plan additional tests using the extraction on column.

Molecular docking of lectins as biosorbents for textile dye removal from wastewater media is a topic of great significance in the fields of environmental and health science. Textile dyes are highly toxic and persistent, posing a serious threat to aquatic ecosystems and human health. Therefore, finding an effective and sustainable method for their removal is crucial. Lectins, which are proteins found in plants and animals, have been extensively studied for their ability to bind with specific sugar molecules. This unique property makes them potential candidates for biosorption applications. Molecular docking techniques allow scientists to study the interaction between lectins and textile dyes at the molecular level, providing valuable insights into their binding affinity and efficiency. By understanding the molecular interactions between lectins and textile dyes, researchers can design more efficient biosorbents that can selectively remove these harmful compounds from wastewater media. In addition, molecular docking studies can help optimize the conditions under which this process occurs, such as pH levels or temperature.Three textile dyes were docked on the lectins of Cupressus sempervirensto evaluate the binding affinity of these drugs.

The lanasyn black is among the most often used in manufacturing and is challenging to take out during the treatment of wastewaters from textile industry. The cloud point extraction was used for their elimination from an aqueous solution. The multivariable process parameters have been independently optimized using the central composite design and the Levenberg?Marquardt algorithm-based artificial neural network for the highest yield of the extraction of lanasyn black via the cloud point extraction. The CCD forecasts the output maximum of 97.01 % under slightly altered process parameters. Still, the ANN?LMA model predicts the extraction yield (99.98 %) using 1.04 g of KNO3, the beginning pH of solution 8.99, the initial content of lanasyn black 24.57 ppm and 0.34 mass % of Triton X-100. With the coefficients of determination of 0.997 and 0.9777, the most recent empirical verification of the model mentioned above predictions using CCD and ANN?LMA is determined to be satisfactory.

In this study, cypress leaves were used for the preparation of a biosorbent to remove brilliant green (BG) and black lanasyn (LB) from aqueous solutions. The influence of several experimental factors, such as time of contact, pH, initial concentration, ionic strength, temperature, stirring speed, and particle size, on the adsorption of these dyes was studied. Contact time s'effect has showed that balance was reached at 30 min with adsorption capacities 9.24 and 4.08 mg/g and elimination rates of 95.97 % and 34 % for BG and LB, respectively. Moreover, the study has shown that the adsorption of the two dyes can be described by pseudo-second-order kinetics. The adsorption isotherms demonstrated that the Freundlich model was satisfactory compared with the Langmuir model for describing the process of adsorption of the two dyes on the cypress. The results showed that the adsorption process is spontaneous, feasible, and endothermic for BG and non-spontaneous and exothermic for LB. Multi-docking reflecting the biosorption of brilliant green and Lanasyn black on the adsorbant surface is proposed. On the fundamental plane, the fractional orthogonal Taguchi plane L16 (45) was used to optimize the conditions for brilliant green adsorption on the cypress. In conclusion, the results showed that cypress leaves could be advantageously used as a low-cost biosorbent for the removal of brilliant green and lanasyn black in wastewater treatment. Resumen. En este estudio se usaron hojas de ciprés para preparar un biosorbente que remueve los colorantes verde brillante (BG) y lanasyn negro (LB) de soluciones acuosas. En la adsorción de estos colorantes se estudió la influencia de varios factores experimentales como tiempo de contacto, pH, concentración inicial, fuerza iónica, temperatura, velocidad de agitación y tamaño de partícula. El efecto del tiempo de contacto mostró que el balance se alcanzó a los 30 min con capacidades de adsorción de 9.24 y 4.08 mg/g y velocidades de eliminación de 95.97 % y 34 % para BG y LB, respectivamente. El estudio mostró que la adsorción de los dos colorantes se puede describir por una cinética de pseudo segundo orden. Para describir el proceso de adsorción de los dos colorantes en las hojas de ciprés, las isotermas de adsorción demostraron que el modelo de Freundlich es satisfactorio comparado con el modelo de Langmuir. Los resultados muestran que el proceso de adsorción es espontáneo, factible y endotérmico para BG, y no espontáneo y exotérmico para LB. Se propone un acoplamiento múltiple reflejando la biosorción del verde brillante y el lanasyn negro sobre la superficie del adsorbente. En el aspecto fundamental, la fracción ortogonal del plano de Taguchi L16 (45) se utilizó para optimizar las condiciones de adsorción del verde brillante en las hojas de ciprés. En conclusión, los resultados muestran que las hojas de ciprés pueden utilizarse como biosorbentes de bajo costo para la remoción de verde brillante y lanasyn negro en el tratamiento de aguas residuales.