Abstract
Adsorption on spinel ferrite nanomaterials is commonly interpreted using descriptors such as surface area, pore volume, surface charge, and experimentally derived kinetic parameters. Although these descriptors are useful for comparing materials, they do not explicitly describe the population of surface sites directly responsible for adsorption. Materials possessing similar BET surface areas, pore structures, and zeta potentials frequently exhibit substantially different adsorption capacities, selectivities, and regeneration stabilities. These observations suggest that geometric surface area alone may not be the most physically relevant descriptor governing adsorption performance. Existing adsorption frameworks and their limitations are summarized in Table 1.