Abstract
Kaolin slurry with specific gravity of 1.12-1.14 is normally used for separation of  palm kernel and palm shell in palm oil milling process. Oil and other contaminants occurred  during the separation were anticipated to affect on the specific gravity of kaolin, thus  decreased the separation capability. Consequently, new batch of virgin slurry is needed. To  reduce the kaolin cost, a method to reclaim the spent kaolin is needed. In laboratory study,  treatment by hot water (50, 70, 90 and 100oC) and by alkaline (1% NaOH)(0.5, 1.0, 2.0 and  2.5 M). It was found that treatment by hot water at 100oC and 1% NaOH of 2.5 M, the spent  kaolin regained its specific gravity at 1.50 and 2.59, respectively. Therefore, the reclaimed  kaolin had the specific gravity equal to that of the virgin kaolin (2.6). There is no significant  difference in the range of NaOH concentrations tested, thus the 1.5 M NaOH was selected
reclamation-of-waste-paolin-in-palm-oil-mill