After bleaching process, the ASTM color value should be no more than 0.5-1.0. The color of paraffin wax could be like water.
2.Used cooking oil or waste oil
Bleaching earth could offer supports for the regeneration of waste lubricants oil, traditional methods are continuously replaced by distillation process, without the acidulation with concentrated sulphuric acid, avoiding the acidic tars which are hard to be removed.
Bleaching earth could remove the impurities like electrolytes and oxidant products under the temperature 100℃ for 30 minutes, without adding extra acid and other cases.
Bleaching earth could absorb the impurities out of the crude extracted oil, like gums, pigments, part of the heavy metal in grinding process, etc.