Green-engineered agricultural-based nano-adsorbent for efficient Cr( <scp>vi</scp> ) removal: batch mechanisms and continuous column performance

loading at a 15 cm bed height under acidic pH, confirming the material's suitability for practical continuous water treatment systems. Thomas and Adams-Bohart model fitting confirmed the mass-transfer-controlled adsorption processes and predictive accuracy for column performance. A comparative evaluation with existing bio-adsorbents highlights a superior Cr(vi) removal capacity, dual functionality (adsorption and photocatalysis), and effective integration into sand filtration systems, thus enabling scalable deployment.