چكيده به لاتين
In recent decades, combustion synthesis with templating has gained attention as an innovative method. This technique offers several advantages, including low cost, higher yield, uniform chemical composition, and higher purity of reaction products. In this study, copper oxide nanoparticles were synthesized using the saturated active layer combustion synthesis method, employing loquat and oleaster leaf extracts as natural fuels, to produce a high-efficiency adsorbent for removing the anionic dye Congo Red from aqueous environments. Experiments were designed using the Taguchi statistical design to determine the optimal sample for achieving the smallest crystallite size and maximum adsorption capacity. In these experiments, the effective parameters included fuel type, fuel amount, and template type, each evaluated at two different levels. The optimal fuel in this research was found to be loquat, resulting in an optimal average crystallite size of 3.18 nanometers. The properties of the optimized nanoparticles were characterized using techniques such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), and specific surface area analysis (BET). The influencing parameters in the adsorption experiments included initial dye concentration (10-80 mg/L), temperature (25-70 °C), contact time (15-360 minutes), pH (2-12), and adsorbent dosage (0.05-0.4 g/L). The monolayer adsorption capacity under optimal conditions, which included a pH of 3, an initial dye concentration of 40 mg/L, an adsorbent dosage of 0.07 g/L, and a temperature of 25 °C, was determined to be 80 mg/g. Results indicated that copper oxide nanoparticles are highly effective in adsorbing Congo Red dye. Furthermore, adsorption isotherm studies showed that the adsorption process followed the Langmuir isotherm at equilibrium and was consistent with a pseudo-second-order kinetic model. Thermodynamic studies also revealed that the process is exothermic and spontaneous.
