Collagenic waste and rubber based resin-cured biocomposite adsorbent for high-performance removal(s) of Hg(II), safranine, and brilliant cresyl blue: A cost-friendly waste management approach.

Abstract

Goat buffing dust (GBD), an abundantly available collagenic-waste and crosslinked styrene butadiene rubber (SBR)-based scalable biocomposite showing excellent physicochemical properties and reusability was synthesized via systematic optimization of torque and time for exclusion(s) of dyes, such as safranine (SF) and brilliant cresyl blue (BCB), and Hg(II). The GBD-aided non-sulfur curing of SBR was attempted via chromane mechanism-based reaction between resin components of GBD and pendant ̶ C=C ̶ of SBR. The decrease in the relative extent of unsaturation in cured-SBRGBD, alteration of crystallinity, surface properties, elevated thermal stabilities, and ligand-selective superadsorption were inferred through extensive microstructural analyses of unadsorbed and/or adsorbed SBRGBD using 13C NMR, O1s-/N1s-/C1s-/Hg4f7/2,5/2-XPS, FTIR, UV-vis, TGA, XRD, FESEM, and EDX. Interactive effects between pHi, temperature, and concentration on adsorption capacities (ACs) were optimized through response surface methodology (RSM). The ionic interaction between SBRGBD and SF, BCB, and Hg(II) was understood through FTIR analyses, fitting of kinetics data to pseudosecond order model, and activation energies. BET and Langmuir isotherms were fitted the best to BCB and SF/Hg(II), respectively. Thermodynamically spontaneous chemisorption showed the maximum ACs of 165.63, 251.18, and 225.56 mg g-1 for SF, BCB, and Hg(II), respectively, at 100 ppm, 303 K, and adsorbent dose = 0.015 g.