Akademik Veri Yönetim Sistemi
Geomicrobiology Journal, 2025 (SCI-Expanded, Scopus)
This study explores the recovery of nickel, cobalt, and iron from chromite beneficiation plant waste using direct and indirect bioleaching with Aspergillus niger. In direct bioleaching, fungal biomass was incubated with the waste. In indirect bioleaching, citric acid produced by Aspergillus niger was used as the leaching agent. The Taguchi L16 method optimized the effects of temperature, leaching time, solid-to-liquid ratio, and stirring speed. Optimum conditions (80 °C, 120 min, 5% solid, 1000 rpm) achieved 88.36% Ni, 88.76% Fe, and 47.65% Co recovery. In contrast, direct bioleaching after 15 days resulted in 9.25% Ni, 45.78% Fe, and 35.55% Co. These results indicate that indirect bioleaching with citric acid is a faster and more effective approach, offering an environmentally friendly strategy for recovering valuable metals from low-grade, silicate-rich industrial waste.