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Zero-valent metals proved high reactivity to adsorb and degrade various contaminants removal. The chemically prepared nZVAl was characterized using UV-Vis spectrum, X-ray diffraction (XRD), and scanning electron microscope (SEM). This investigation explores the adsorption effect of nZVAl powder toward soluble organic compounds exemplified by chemical oxygen demand (COD) standard solution. The effect of different operating parameters was studied to identify the best removal conditions. All variable and covariable data were introduced to build statistical models. The effect of the operating parameter was studied at different pH (3-10), nZVAl dosages (0.1-0.8 g), at different times (5-120 minutes), stirring rate (50-400 RPM), and initial COD concentration (100-800 mg/L). The obtained results displayed that nZVAl is effective in the removal of standard COD solutions, where the removal percentages were 56% and 96% for 800 ± 18.0 and 100 ± 11.8 mg/L COD, respectively, at 10 minutes after using nZVAl dry dosage 0.6 g/L, pH 8, and rate 100 rpm. Also, the effect of nZVAl on other wastewater contaminants removal was studied and compared with Egyptian law for draining wastewater into nonfresh water (drainage-lakes-ponds) No. 48 of 1982 limits. The results of adsorption isotherm and kinetic model of COD fitted well to Freundlich isotherm and pseudo second order, respectively. Nonlinear artificial intelligence neural network (ANN) importance data agree with linear response surface methodologies (RSM) in simulating the adsorption of COD onto nZVAl indicating that the most significant coverable is adsorbent dose. Finally, this study appropriates using nZVAl in highly contaminated wastewater rather than other chemical and biological processes.

Nanotechnology especially Zero Valent metals is a modern technology for the degradation of extensive ranges of biological wastewater contaminants. Due to their effectiveness, economically and safely properties, this study successfully prepared and characterized nanoZero Valent Iron (nZVI) to be encapsulated into natural alginate biopolymer. The effect of operating parameters was studied at different environmental conditions; pH, dose (g/L), contact time (min), stirring rate (rpm), and BOD concentrations. Adsorption isotherm, kinetic studies, and statistical analysis (Response Surface Methodology (RSM) and Artificial neural networks (ANNs)) were examined to describe the removal behavior. The obtained results indicated that the maximum removal efficiency was 81.2 % for initial BOD concentration 300 mg/L, at pH 7, using wet dose 3g/L, 25min, and stirring rate 200 rpm. Also, adsorption and kinetic data indicated that the adsorption mechanism runs toward the Sips model to approximate the Freundlich model at low concentration and to solve the Freundlich limitation at high concentration with a maximum adsorption capacity of 181mg/g. Kinetic results describe the solid transformation from one phase to another at a constant temperature by approving Avrami model. Finally, RSM results agree with ANNs results that the “Concentration effect” is the most significant variable that controls the removal efficiency.