Hydrometallurgical recovery of α-Fe2O3from red mud and photo-Fenton degradation of organic dye using CuO promoted α-Fe2O3

The ecological balance is disturbed by the massive generation of solid waste (red mud) from aluminum industries. It contained various types of metal oxides with different proportions, and it is essential to extract these valuable metals to maintain sustainability. The hydrometallurgical route is applied to extract hematite (alpha-Fe2O3) from red mud. This route involves leaching, solvent extraction, and precipitation. The alpha-Fe(2)O(3)is mixed with different weight percentages of CuO to form a heterostructure (CuO/alpha-Fe2O3). The malachite green (MG) is degraded using the alpha-Fe2O3-CuO catalyst for photo-Fenton reaction. All the composites are characterised by XRD, FTIR, UV-vis DRS, PL, and electrochemical study. XRD figure confirmed that hematite (alpha-Fe2O3) is extracted successfully from red mud, and goethite (alpha-FeOOH) is suppressed. The reducibility nature of CuO, created a synergism between alpha-Fe(2)O(3)and CuO, which leads to suppression of e(-)/h(+)recombination by proper charge transfer. It is confirmed through PL spectra and electrochemical study (Nyquist plot). 20CuO/alpha-Fe(2)O(3)showed the maximum degradation (98%) of malachite green (MG). [GRAPHICS] .