Synthesis, Characterization and Applications of Silica Nanoparticles from Sugarcane Bagasse in the Removal of Tetracycline from Wastewater

Background and Objective: The persistence of tetracycline in aquatic environments poses serious ecological and health risks due to its resistance to conventional treatment methods. This study explores the potential use of sugarcane bagasse, a low-cost agricultural byproduct, as a sustainable source for synthesizing silica nanoparticles (SNPs) aimed at removing tetracycline from water. The main objective was to synthesize, characterize, and evaluate the adsorption efficiency of SNPs under varying operational conditions. Materials and Methods: Silica nanoparticles were synthesized from sugarcane bagasse via alkaline extraction and acid precipitation using the sol-gel method, a cost-effective and eco-friendly approach. The synthesized SNPs were characterized using X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray analysis (SEM-EDX), UV-Vis spectroscopy, and Fourier-transform infrared (FTIR) spectroscopy. Adsorption experiments were conducted to evaluate the effects of pH, contact time, and adsorbent dosage on tetracycline removal. Results: The XRF analysis confirmed 96.2% silica content in the synthesized SNPs. The FTIR and UV-Vis spectra indicated the presence of Si-O-Si bonds, silanol, and siloxane groups, confirming silica formation. The XRD patterns revealed an amorphous structure, while SEM-EDX showed uniformly distributed, spherical, and porous SNPs with 60.92% silicon composition. Optimal adsorption was achieved at pH 7, 60 min contact time, and 0.8 g adsorbent dosage, demonstrating high tetracycline removal efficiency. Conclusion: The study demonstrates that sugarcane bagasse is a viable precursor for producing silica nanoparticles with strong adsorption capabilities for tetracycline removal. This approach offers a sustainable and cost-effective strategy for wastewater treatment.