Monica, C. P., Anggraeni, V. P. . C., Sumada, K. ., Sari, N. K. . and Pujiastuti, C. . (2025) “Optimization of Acetone Concentration and Reflux Ratio for Enhanced Oil Extraction from Spent Bleaching Earth: A Response Surface Methodology Approach”, Indonesian Journal of Environmental Management and Sustainability, 9(4), pp. 183-191. doi: 10.26554/ijems.2025.9.4.183-191.