High-performance boron nitride-halloysite nanocomposite as a recyclable adsorbent for methylene blue removal

• Achieved 100% removal of Methylene Blue within 40 minutes for concentrations ranging from 5-50 mg/L. • Maximum adsorption capacity of 473.6 mg/g, superior to many existing adsorbents. • Maintained high performance over multiple adsorption-desorption cycles, demonstrating excellent stability and recyclability. • The nanocomposite offers a sustainable solution for dye removal, with high reusability and minimal performance degradation over cycles. • Potential for large-scale use in textile wastewater treatment due to its rapid adsorption kinetics, high efficiency, and cost-effectiveness. The development of efficient and renewable adsorbents for industrial wastewater decolorization remains a critical environmental challenge. In this study, we report the synthesis of a novel boron nitride-halloysite (h-BN-HNT) nanocomposite via a facile solution mixing method and its outstanding performance in removing methylene blue from aqueous solutions. Morphology, chemical structure, and crystallinity of the nanocomposite were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD), confirming successful functionalization and revealing a hierarchical porous structure with high potential for dye adsorption. The nanocomposite material demonstrated exceptional performance in water decolorization, achieving complete methylene blue removal within 40 minutes for all concentrations studied (5-50 mg/L), with a maximum adsorption capacity of 473.6 mg/g at 50 mg/L initial concentration. Kinetic studies revealed that the adsorption process follows pseudo-second-order kinetics with excellent correlation (R²=0.9953), indicating chemisorption as the dominant mechanism. Statistical error analysis confirmed the model validity with low chi-squared (χ²=2.18), sum of squared errors (SSE=24.5), and average relative error (ARE=1.15%) values. Notably, the nanocomposite also demonstrated excellent recyclability, maintaining over 95% removal efficiency after five consecutive adsorption-desorption cycles, confirming its practical reusability. These results establish the h-BN-HNT nanocomposite as a highly promising candidate for practical applications in industrial wastewater treatment, offering a sustainable and cost-effective solution for the removal of cationic dyes.