Atmasari, A.D. et al. 2020. Adsorption of Cr on Liquid Waste of Tannery Industry using Banana Peel Charcoal in various pH and Time Activation. Indonesian Journal of Chemistry and Environment. 2, 1 (Feb. 2020), 19–24. DOI:https://doi.org/10.21831/ijce.v2i1.30292.