The increasing discharge of synthetic dyes into industrial wastewater necessitates sustainable and low-cost treatment strategies. This study valorizes orange seed powder (OSP), an abundant agro-food residue, as a novel biosorbent for Congo red (CR) removal through a combined experimental and molecular simulation approach. Raw OSP was prepared solely by drying and grinding, without chemical activation, emphasizing its practical applicability and environmental sustainability. Physicochemical characterization using FTIR, SEM, and EDX confirmed adsorption-induced structural and compositional changes. Batch experiments evaluated the effects of initial dye concentration, adsorbent dosage, pH, temperature, and contact time. Equilibrium data were well fitted by the Langmuir and Freundlich isotherm models (R2 ≈ 0.99), with a maximum adsorption capacity of 258.39 mg g−1 at 25 °C and pH 4, and a removal efficiency exceeding 99.55%. The adsorption kinetics followed a pseudo-second-order model, while intraparticle diffusion contributed to the rate-controlling mechanism, as indicated by the Weber–Morris model. OSP demonstrated excellent regeneration performance over five adsorption–desorption cycles, retaining more than 96% of its initial CR removal efficiency when regenerated with methanol. Grand Canonical Monte Carlo (GCMC) simulations revealed that adsorption is primarily driven by electrostatic interactions, hydrogen bonding, and π–π stacking interactions, in good agreement with the experimental findings. Overall, raw OSP represents an efficient, regenerable, and sustainable biosorbent, highlighting the originality of integrating experimental investigations with GCMC simulations for wastewater treatment applications.
Nuclear systems near nucleon drip lines have great importance in studying nucleon–nucleon force properties. However, such unstable systems have few experimental data. Due to technical development in recent years, new experimental data assembly provides huge information to analyze possible observation of new phenomena. In the aim of exploring proton-rich nuclei near closed shells, we have studied the even–even Z = N nuclei in \(28<Z<50\), \(50<N<82\) mass region. This study is based on the investigation of the core polarization and the monopole effect originated from the interactions between the magic core and the valence nucleons. In this context, this work includes the calculation of the energy spectra of Zr, Mo, Ru, Pd and Cd nuclei. These calculations were performed in the framework of the nuclear shell model using NuShellX@MSU code. Using recent single-particle energies, the three-body effect consideration introduces some modifications on the effective interaction. By means of the modified interaction, some nuclear properties of the studied nuclei have been evaluated. The results show a reasonable agreement with the available experimental data. The monopole effect is an important component of nucleon–nucleon interaction, in which its consideration gives a reasonably agreement with available data.
11 April 2025 in Radiological Physics and Technology