A high cost of high-purity materials is one of the major factors that limit the application of ceramic membranes. Consequently, the focus was shifted to using natural and abundant low-cost materials such as zeolite, clay, sand, etc. as alternatives to well-known pure metallic oxides, such as alumina, silica, zirconia and titania, which are usually used for ceramic membrane fabrication. As a contribution to this area, the development and characterization of new low-cost ultrafiltration (UF) membranes made from natural Tunisian kaolin are presented in this work. The asymmetric ceramic membranes were developed via layer-by-layer and slip-casting methods by direct coating on tubular supports previously prepared from sand and zeolite via the extrusion process. Referring to the results, it was found that the UF kaolin top layer is homogenous and exhibits good adhesion to different supports. In addition, the kaolin/sand and kaolin/zeolite membranes present an average pore diameter in the range of 4–17 nm and 28 nm, and water permeability of 491 L/h·m²·bar and 182 L/h·m²·bar, respectively. Both membranes were evaluated in their treatment of electroplating wastewater. This was done by removing oil and heavy metals using a homemade crossflow UF pilot plant operated at a temperature of 60 °C to reduce the viscosity of the effluent, and the transmembrane pressure (TMP) of 1 and 3 bar for kaolin/sand and kaolin/zeolite, respectively. Under these conditions, our membranes exhibit high permeability in the range of 306–336 L/h·m²·bar, an almost total oil and lead retention, a retention up to 96% for chemical oxygen demand (COD), 96% for copper and 94% for zinc. The overall data suggest that the developed kaolin membranes have the potential for remediation of oily industrial effluents contaminated by oil and heavy metals.

Paracetamol (PCT) and chloramphenicol (CPL) can have unfavorable impacts on human health, as well as on natural ecosystems. These substances contribute to the aquatic environment’s contamination and disturb the performance of municipal wastewater treatment systems, causing ecosystem disruption and microbial resistance. In this study, activated carbon produced from sawdust (ACs) was synthesized utilizing the chemical activation process for the removal of both PCT and CPL compounds from an aqueous solution. ACs has a primarily microporous structure with a significant specific surface area of 303–1298 m²/g, total pore volume of 0.462 cm³/g and bimodal distribution of pores of 0.73–1.7 nm. The removal efficiencies for PCT and CPL with the low-cost activated carbon, determined at the optimum dose (750 mg/L for PCT and 450 mg/L for CPL), were significantly high at 85% and 98%, respectively. The adsorption kinetics for both pharmaceuticals exhibited a quick initial decline. For PCT and CPL adsorption, the equilibrium was attained after just 20 and 90 min, respectively. The Langmuir isotherm model and the pseudo-second-order kinetics model offered the best fits for the adsorption of both compounds. Additionally, the central composite design (CCD) and Box–Behnken design (BBD) were used to optimize the experimental adsorption conditions using a response surface methodology (RSM). On the basis of the findings, it is evident that activated carbon made from sawdust may be used as a new, effective alternative adsorbent for removing PCT and CPL in aqueous environments.

Several processes have been developed to treat the textile effluents. Membrane technologies are among the most reliable processes for purifying these effluents. However, due to high costs, only reduced quantities are being treated. The recycling practices of treated textile effluents (TTE) in agriculture have not been appropriately explored. This work evaluates the quality of waters treated by membrane processes and puts forward a scenario for optimizing TTEs in agriculture. Four types of TTE have been tested to irrigate Sesbania bispinosa plants: water from biological treatment (BT) and water from three membrane processes after BT (Ultrafiltration (UF), Nanofiltration (NF), and Reverse Osmosis (RO)). The results indicate that the NF and RO membranes have a high affinity to remove monovalent and multivalent ions. Indeed, the removal of SO₄²⁻, Na⁺, and Cl⁻ by NF was 83, 61, and 55%, respectively. Thus, the RO reduces approximately 96% of these elements. Irrigation with NF and RO waters has no negative effect on the soil and Sesbania plants, contrary to BT and UF waters. It appears that the reuse of TTE resulting from BT is not a good alternative; however, by carrying out additional treatments by NF and RO, their reuses have been made possible. The achieved results are a proposal to simultaneously solve three major problems affecting most of the world’s population: (1) environmental pollution by reducing the discharge of untreated textile effluents and improving the quality of this discharged water; (2) the pressure on water resources in the agricultural sector by replacing a conventional resource with a non-conventional resource (TTE); and (3) the lack of fodder, especially in the summer, by opting for crops that adapt to the quality of these TTE.

In the last decade, the development of a new generation of membranes based on low-cost materials has been widely studied. These membranes demonstrate significantly higher performance than the conventional ceramic membranes currently used in membrane separation technology. This work is focused on the development of a low-cost flat UF ceramic membrane composed completely of sepiolite using a uniaxial pressing method with dimensions of 5.5 cm of diameter and 3 mm of thickness. The sintering temperatures used were from 650 to 800 °C. Several properties, such as morphology, porosity, permeability, mechanical strength, and chemical resistance, are investigated. The results show that the mean pore diameter is increased from 40 to 150 nm when the sintering temperature increases from 650 °C to 800 °C. At these temperatures, excellent mechanical strength of 18 MPa to 22 MPa and high chemical resistance were achieved. SEM results revealed a crack-free structure with a uniformly smooth surface. Permeability tests were conducted using dead-end filtration. The sepiolite membrane demonstrated an improvement in its water permeability from 18 to 41 L·m⁻²·h⁻¹·bar⁻¹ when the sintering temperature increased from 650 °C to 750 °C. The efficiency of the sepiolite membranes sintered at 650 °C and 700 °C were evaluated with the application of the removal of paracetamol (PCT) and indigo blue (IB) dye separately from two synthetic aqueous solutions representing the pharmaceutical and textile sectors. Excellent removal efficiency of almost 100% for both contaminants was observed at ambient temperature and a pressure of 3 bars. Membrane regeneration was achieved through simple rinsing with deionized water. According to this finding, the UF sepiolite membrane demonstrated reversible fouling, which is consistent with the fouling coefficient “FRR” value higher than 90%.

Water resource management scenarios have become more crucial for arid to semi-arid regions. Their application prerequisites rigorous hydrological modelling approaches since data are usually exposed to uncertainties and inaccuracies. In this work, Soil Water Assessment Tool (SWAT), an open source semi-distributed, continuous-time, process-based physical hydrological model is used to model hydrological processes and eventually calculate groundwater recharge estimations in Seybouse basin, Northeast Algeria. The model uses estimated rainfall to calibrate the model with observed discharge from hydrometric stations. Model calibration and validation are performed over four hydrometric stations located in the basin. Uncertainty analysis and sensitivity analysis supported the calibration period. SUFI-2 algorithm is used for uncertainty estimations along with a global sensitivity analysis prior to calibration simulations. Simulated flood hydrographs showed generally good accuracy with few misfits on the peaks. The model obtained satisfactory and consistent calibration and validation results for which the Nash score varied from 0.5 to 0.7 for calibration and from −0.1 to 0.6 for validation and R² from 0.6 to 0.7 for calibration and 0.03 to 0.8 for validation. Moreover, estimated water budget values show strong similarities with the observed values found in the literature. The present work shows that the rigorously calibrated and validated SWAT model can simulate hydrological processes as well as major high and low flows using estimated rainfall data.