Magnetic banana fiber catalyst for efficient Cr(VI) reduction: a sustainable approach to waste valorization and water treatment

This study focused on producing banana fiber (BF) from waste banana bunch stalks and imparting magnetic properties (Fe 3 O 4 ) to the fibers. Characterization analyses confirmed the successful synthesis of the BF-Fe 3 O 4 catalyst. Its effectiveness in removing Cr(VI) via a Fenton-like process using heterogeneous catalysts was investigated. Key parameters were optimized to evaluate the catalyst's potential, including pH, catalyst dosage, contact time, H 2 O 2 concentration, and Cr(VI) concentration. Under optimal conditions—pH 2.0, 0.5 g/L BF-Fe 3 O 4 , 5 μL/L H 2 O 2 , and a 60-min contact time—100 % removal of a 10 mg/L Cr(VI) solution was achieved. Reusability tests demonstrated consistent removal efficiency even after five cycles. Kinetic studies indicated that the Fenton-like process followed a second-order kinetic model . Overall, the BF-Fe 3 O 4 catalyst, derived from banana waste, proved effective for Cr(VI) removal while offering cost-effectiveness, reusability, and a sustainable approach to waste valorization. • Production of banana fiber from waste banana bunch stalks • Production of banana fiber-Fe 3 O 4 (BF- Fe 3 O 4 ) heterogeneous catalysts • 100 % of Cr (VI) removal indicated that the BF-Fe 3 O 4 catalyst was successful for wastewater treatment. • Economical, environmentally friendly, and cheap catalyst