Sembiring, Junita Br, et al. “Development of a Peanut Shell-Derived Chitosan–Activated Carbon Composite As a Sustainable Adsorbent for Permanganate (MnO₄⁻) Removal from Aqueous Solution”. Hydrogen: Jurnal Kependidikan Kimia, vol. 14, no. 4, Aug. 2026, doi:10.33394/hjkk.v14i4.21354.