Egyptian Petroleum Research Institute

The conventional wastewater treatment systems were found to be limited by the ability to simultaneously remove divalent lead and cadmium, so a novel multiphase engineered COF-Biochar-Al2O3 ternary composite was synthesized through the hydrothermal route for synergistic removal of both divalent Pb2+ and Cd2+ from wastewater. Advanced characterizations by XRD, FTIR, SEM, TEM, and XPS confirmed the successful integration of the phases. The results of the batch experiments exhibited strong pH dependency with optimal values at pH 6.0 for Pb2+ and pH 7.0 for Cd2+, and exceptionally high values of maximum monolayer capacity qmax (365.0 mg/g for Pb2+ and 265.0 mg/g for Cd2+). The kinetic profiles were found to be strictly following the PSO model (R2 ≥ 0.998) thus confirming chemisorption as the rate limiting step. Thermodynamic analysis confirmed spontaneous (ΔG° = −3.29 and −3.12 kJ/mol for Pb2+ and Cd2+ at 298 K), endothermic (ΔH° = +24.6 and + 22.8 kJ/mol), and entropy-driven (ΔS° = +95.2 and + 88.5 J/mol.K) processes. XPS confirmed a multi-modal chemisorption network involving electrostatic attractions, strong inner-sphere coordination with COF imine (C=N) groups, surface complexation on deprotonated alumina (Al–O-), and high intensity cation-π interactions throughout the graphitized biochar. Ternary hybrid showed highest structural resilience, retaining 56.5% (Pb2+) and 46.2% (Cd2+) efficiency after 10 continuous cycles due to the physical buffer role of the biochar and the alumina. The results demonstrate that it is an efficient, economically feasible architecture for industrial use in removing contaminants from wastewater.

The petroleum refining industry uses catalysts containing molybdenum for mild hydrogenation processes. The amount of wasted catalyst produced by these catalytic processes is enormous. Molybdenum (Mo), nickel (Ni), and cobalt (Co) are the main valuable metals in Mo spent catalysts (SC), usually being supported on Al2O3. As environmental consciousness and the demand for metal values expand, catalysts may be used as additional sources for metal recovery; however, a cost-effective and efficient method is still challenging. This study developed an efficient procedure for Mo recovery from waste Mo/alumina catalyst as a value-added material. Spent catalyst was leached with HCl acid, and the impact of various parameters, including the temperature, solid/liquid ratio, time, and acid concentration, on the Mo and Al recovery was investigated. Leaching kinetics were explored using the shrinking core model (SCM) and Avrami model, revealing that the process is mainly controlled by product layer diffusion. From the leaching solutions, Mo-based materials were prepared via a solvothermal method in mild pressure (MoS2-R) and high pressure (MoS2-A) conditions. The MoS2-A sample was calcined at 800 °C under argon to give a more crystalline structure (MoS2-C), and the Al impurity in the leaching solution was removed using ammonia buffer to prepare pure MoS2 (96

Water scarcity and contamination remain pressing global challenges, particularly in regions where conventional purification methods are either economically or environmentally unsustainable. This paper investigates bio-inspired water purification strategies that mimic natural filtration processes aiming to provide scalable and sustainable solutions for clean water access. By clearly defining the problem at the outset, the abstract emphasizes the importance and urgency of this research. Herein, a new polyvinyl chloride (PVC) polymeric membrane integrated with magnetic natural waste-derived nanosilica Fe3O₄@SiO₂ core-shell (PVC/Fe3O₄@SiO₂) is synthesized and applied for getting rid of oil from oil-in-water emulsions. PVC/Fe3O₄@SiO₂ membrane is characterized using a variety of techniques including FTIR, XRD, SEM, TEM, and AFM. The membrane’s surface topography and roughness which is important for understanding how it interacts with oil droplets is examined using AFM analysis. The findings confirmed uniform nanoparticle dispersion (150 ± 25 nm), 72 ± 3

The continuous release of cationic dyes such as methylene blue (MB) into aquatic systems poses serious environmental concerns due to their chemical stability, persistence, and potential toxicity. In this study, a novel ternary hybrid adsorbent (CS-UiO66-NH2/TpPa-1) was rationally engineered by integrating chitosan with a metal–organic framework (UiO-66-NH2) and a covalent organic framework (TpPa-1) to enhance adsorption performance through synergistic effects. The composite structure combines the functional groups of chitosan, the high surface area and stability of the MOF, and the π-conjugated framework of the COF, enabling multiple interaction pathways. Comprehensive characterization (FTIR, XRD, SEM, BET, TGA, XRF, and zeta potential) confirmed successful hybridisation and the formation of a hierarchical micro–mesoporous architecture with pH-responsive surface charge (pHPZC ≈ 6.4). Batch adsorption studies demonstrated that MB removal is strongly influenced by pH, contact time, initial concentration, and temperature, with optimal performance at pH 7 and 25 °C. The composite achieved a high adsorption capacity of 476.64 ± 3.6 mg g⁻1 and a removal efficiency of 98.34 ± 0.7

The development of multifunctional materials capable of efficient adsorption and catalytic degradation of organic pollutants is critical for sustainable wastewater treatment. In this study, a novel magnetic ternary composite based on MOF-808, poly (ionic liquid) (PIL), and Fe3O4 nanoparticles. Structural characterization using XRD, FTIR, SEM, TEM, BET, and TGA confirmed the successful incorporation of PIL and Fe3O4 into the MOF framework, resulting in enhanced porosity, improved thermal stability, and modified surface functionality. The composite exhibited significantly enhanced adsorption performance, achieving a maximum adsorption capacity of 612 ± 31 mg g−1, compared to 217 ± 11 mg g−1 for pristine MOF-808. Adsorption kinetics followed a pseudo-second-order model, indicating a chemisorption-dominated process. Furthermore, the composite demonstrated superior photocatalytic activity under visible light through efficient activation of peroxymonosulfate, achieving 96 ± 3.84