Microbial fuel cells are a new alternative for sustainable energy generation and wastewater treatment technology. To scale up this technology, cost-effective electrodes are required. The electrochemical reduction of oxygen at the cathode is a key reaction for power generation. Noble metals, especially Pt, are extensively used as cathode catalysts in MFC; however, its application is limited to its high cost and catalyst poisoning. Ferroelectric materials are reported as a good candidate due to their spontaneous polarization. The main objective of this study is to prepare and characterize the cost-effective ferroelectric materials LiTa_0.6 Nb_0.4 O₃ and Li_0.95 Ta_0.57 Nb_0.38 Mg_0.15 O₃ in order to test their catalytic activity in air-cathode MFC. Powders were prepared following the solid-state synthesis and characterized using Scanning Electron Microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction. To evaluate the electrochemical performance of the catalysts, electrochemical studies such as EIS, CV, LSV, and CA were conducted. In MFC, the performance of our material has been investigated using COD determination and polarization measurement. The obtained results demonstrate the potential of Li_0.95 Ta_0.57 Nb_0.38 Mg_0.15 O₃ as a low-cost and effective catalyst material in MFCs, showing a high COD removal up to 75%, and power-density output of 764 mW/m².

The present study investigates the effect of manganese incorporation on the structural, dielectric, and waste bioconversion of LiTaO₃ ferroelectric material. Conventional solid-state synthesis techniques were utilized to produce powder samples, which were subsequently analyzed using room-temperature X-ray diffraction (XRD) for phase identification. The analysis revealed that the material forms a continuous solid solution within the composition range of 0 to 25 mol% of manganese (Mn), exhibiting R3c-Rombohedral symmetry. Thermal investigations of Raman spectra permitted approaching the ferroelectric–paraelectric phase transition, and dielectric measurements were performed in all investigated samples. The results show that the temperature of ferroelectric-paraelectric phase transition (Tc) decreased with the increasing Mn content. Optical properties of the prepared materials were also measured and tested as photocathodes for microbial fuel cells (MFCs), showing promising performance for x = 0.10, which exceeds values found with other dopants.

Lagoon wastewater treatment systems, introduced in 1970, have become a preferred economic solution in Morocco due to favourable climatic and economic conditions. However, these facilities often face performance problems, particularly related to excessive hydraulic and pollutant loads, resulting in treatment efficiencies below regulatory standards for urban discharges. Waste stabilization ponds in Morocco show average reduction rates of 70 % for chemical oxygen demand, 65 % for biochemical oxygen demand during 5 days, and 62 % for suspended solids. This study aims to evaluate the performance of seven lagoon treatment plants in different regions of the country and identify solutions to ensure compliance with discharge standards. The Moroccan experience in biological lagoon treatment is valuable for improving purification efficiency, with observed reductions of chemical oxygen demand, biochemical oxygen demand during 5 days, and suspended solids of 65 %, 54 %, and 62 % respectively, proposing strategies to optimize these processes and ensure adherence to specific norms.

The Moroccan olive oil sector produces large volumes of olive mill wastewater (OMW), a highly polluting effluent rich in polyphenols and organic load (chemical oxygen demand: COD). This study explores an integrated solution using Microbial Fuel Cells (MFCs) to simultaneously remediate OMW and...

Biodiesel has attracted considerable attention as a promising renewable fuel because it burns cleaner than conventional diesel and produces lower pollutant emissions. In this work, a CaO-based heterogeneous catalyst was prepared by calcining drinking water pipeline scale deposits at 900 °C for 2 h. X-ray diffraction (XRD), Fourier transforms infrared (FT-IR) spectroscopy, thermogravimetric analysis (TG-DTA), atomic emission spectrometry ICP-AES, and scanning electron microscopy SEM were used to analyze all the solids. Characterization results revealed that the raw scale deposits mainly consisted of calcite (CaCO₃) containing trace amounts of metallic impurities. Catalytic activity was performed on a high-temperature calcined scale material. The effect of catalysts quantities, methanol to oil molar ratios, and reaction periods were researched in order to enhance the biodiesel’s quality. The obtained results showed that at 60 °C, the methyl ester content was 96% under transesterification conditions utilizing a catalyst concentration of 3%, a methanol/oil molar ratio of 12, and a reaction duration of 120 min. The produced biodiesel was also analyzed using FT-IR and NMR. Their properties were recorded according to the ASTM D6751 specifications of biodiesel and were discovered to be within the parameters.