Yudha Gusti Wibowo, Hana Safitri, Kusumawati, Wahyu Dera Aini, Richar Farantino, Simparmin Br Ginting, Asnan Rinovian, Setyo Budi Kurniawan, Khairurrijal Khairurrijal, Tarmizi Taher, Wida Banar Kusumaningrum, Sudibyo Sudibyo, Ahmad Tawfiequrrahman Yuliansyah, Himawan Tri Bayu Murti Petrus
This study investigates the synthesis and performance of a biochar-based composite, integrating montmorillonite (MMT) and ZnAl layered double hydroxide (LDH), for the removal of Fe and Mn from acid mine drainage. The biochar_MMT_ZnAl LDH composite, synthesized from solid waste materials, was characterized using BET, XRD, FTIR, TGA, and SEM-EDS analyses. The material demonstrated a surface area of 117.54 m2/g and a pore volume of 0.21 cm3/g, significantly surpassing non-composite biochar with a surface area of 14.81 m2/g. The batch sorption experiment showed rapid adsorption kinetics, achieving 99% Mn removal within 7 min at 0.5 g adsorbent dosage, reducing Mn concentration from 100 mg/L to 0.07 mg/L. For Fe, an 87% reduction was achieved after 400 min using 0.5 g of plain biochar, while biochar_MMT_ZnAl LDH showed superior adsorption performance with a final Fe concentration below 0.07 mg/L. Adsorption isotherm analysis indicated that biochar followed the Dubinin–Radushkevich model, while the composites adhered to the Redlich–Peterson model. Kinetic studies revealed a strong fit with the Pseudo-Second-Order model (R2 = 1 for biochar_MMT), suggesting chemisorption as the dominant mechanism. Thermodynamic analysis confirmed the spontaneity and endothermic nature of the adsorption process, with ΔG values ranging from − 18,758 to − 92,932 J/mol for Fe and Mn removal. The findings highlight the potential of biochar-based composites in developing cost-effective and environmentally sustainable solutions for acid mine drainage treatment. © The Author(s) 2025.
Department of Chemical Engineering (Sustainable Mineral Processing Research Group), Universitas Gadjah Mada, Jalan Grafika No. 2, Bulaksumur, Depok, Sleman, Yogyakarta, 55281, Indonesia; Center for Green and Sustainable Materials, Institut Teknologi Sumatera, Terusan Ryacudu, Way Hui, Jati Agung, Lampung Selatan, 35365, Indonesia; Department of Chemical Engineering, Universitas Lampung, Jl. Prof. Dr. Ir. Sumantri Brojonegoro No. 1, Gedong Meneng, Kec. Rajabasa, Kota Bandar Lampung, Lampung, 35141, Indonesia; Research Center for Mining Technology, National Research and Innovation Agency, Jl. Ir. Sutami KM. 15 Tanjung Bintang, South Lampung, Lampung, 35361, Indonesia; Department of Chemical and Process Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, Selangor, Bangi, 43600 UKM, Malaysia; Research Center for Environment and Clean Technology, National Research and Innovation Agency (BRIN), Jakarta Pusat, Indonesia; Department of Physics, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jalan Ganesha 10, Bandung, 40132, Indonesia; Department of Environmental Engineering, Institut Teknologi Sumatera, Lampung Province, 35365, Indonesia; Unconventional Geo-resources Research Group, Faculty of Engineering, Universitas Gadjah Mada, Jalan Grafika No. 2 Kampus UGM Bulaksumur, D.I. Yogyakarta, 55281, Indonesia; Sustainable Mining and Environmental Research Group, Department of Mining Engineering, Faculty of Technology Industry, Institut Teknologi Sumatera, Lampung Province, 35365, Indonesia; Research Center for Biomass and Bioproducts, Badan Riset dan Inovasi Nasional, Bogor, Indonesia