Preparation of Palm Oil Mill Effluent Sludge Biochar for the Treatment of Landfill LeachateMohammed J.K. Bashir, Jing Wei Wong, Sumathi Sethupathi, Ng Choon Aun and Lim Jun WeiMATEC Web Conf., 103 (2017) 06008DOI: https://doi.org/10.1051/matecconf/201710306008