Bauxite residue (BR), a polymetallic waste, offers significant potential for valuable metal recovery. This study introduces a low temperature H2 reduction-alkaline (NaOH) roasting, followed by water leaching - wet magnetic separation, aimed at efficient recovery of Fe, Na, and Al, alongside non-magnetic tailings (Ca, Ti, and Si). To minimize H2 consumption, 5 vol % H2 + 95 vol % N2 with 200 L/kg was sufficient. Utilizing response surface methodology (RSM), the optimal H2 reduction process conditions were determined as a temperature of 600 °C and a time of 120 min with 20 wt% NaOH. Under these conditions, the maximum recoveries achieved were 74.4 % Fe (grade = 63.6 %), 84.6 % Al, and 91.6 % Na, with RSM model predicted Fe, Al, and Na recovery values at optimum conditions closely matching experimental results (<5 % deviation). The proposed sustainable process minimizes waste and offers a possible solution for BR processing.
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