The triphenyl group
(trityl radical) possessing three-phenyl rings,
self-assembled through aromatic π–π stacking interactions,
can form interesting crystalline organic nano-flowers. In this work,
we have synthesized a hybrid material of 1,2-bis(tritylthio)ethane
and magnetite, which reduces toxic Cr(VI) to non-toxic Cr(III). We
validated the efficacy of the hybrid in reducing toxic Cr(VI) along
with three other adsorbent systems. Among the five adsorbent systems
tested, we observed that human hair has higher Cr removal efficiency,
which prompted us to explore further using different mechanical forms
of human hair. Pulverized hair (PH), hair powder (HP), and raw hair
(RH) were evaluated by employing different reaction factors such as
the adsorbent dose, pH, initial Cr(VI) concentration, and contact
time. The comparative evaluation showed that PH has greater adsorption
capacity (15.14 mg/g), followed by RH (13.27 mg/g) and HP (10.5 mg/g).
While investigating the adsorption mechanism, we observed that it
follows pseudo-second-order kinetics suggesting chemisorption. The
Freundlich isotherm model fitted well for Cr(VI) adsorption by human
hair, suggesting a multi-layered adsorption process. Overall, this
study promises a cost-effective and eco-friendly bio-adsorbent for
Cr(VI), which may be scaled up to design automated industrial waste
disposal systems.