Solid waste collagen-associated fabrication of magnetic hematite nanoparticle@collagen nanobiocomposite for emission-adsorption of dyes

The strategic utilization of hazardous particulate waste in eliminating environmental pollution is an important research hotspot. Herein, abundantly available hazardous solid collagenic waste of leather industry is converted into stable hybrid nanobiocomposite ([email protected]) comprising magnetic hematite nanoparticles (HNP) and solid waste derived collagen (SWDC) via co-precipitation method. The structural, spectroscopic, surface, thermal, and magnetic properties; fluorescence quenching; dye selectivity; and adsorption are explored via microstructural analyzes of [email protected] and dye [email protected] using 1H nuclear magnetic resonance, Raman, ultraviolet-visible, Fourier-transform infrared (FTIR), X-ray photoelectron, and fluorescence spectroscopies; thermogravimetry; field-emission scanning electron microscopy; and vibrating-sample magnetometry (VSM). The intimate interaction of SWDC with HNP and elevated magnetic properties of [email protected] are apprehended via amide-imidol tautomerism associated nonconventional hydrogen bondings, disappearance of goethite specific –OH def. in [email protected], and VSM. The as-fabricated reusable [email protected] is employed for removing methylene blue (MB) and rhodamine B (RhB). Chemisorption of RhB/MB in [email protected] via ionic, electrostatic, and hydrogen bonding interactions alongside dimerization of dyes are realized by ultraviolet-visible, FTIR, and fluorescence studies; pseudosecond order fitting; and activation energies. The adsorption capacity = 46.98–56.14/22.89–27.57 mg g−1 for RhB/MB is noted using 0.01 g [email protected] within 5–20 ppm dyes and 288–318 K.