Used cooking oil when consumed will cause some diseases to humans. However, if it is discharged into the environment, it will pollute the surrounding environment. In order that the used
cooking oil can be reused, purification process is needed by means of adsorption technique. One
of the factors that influencing the effectiveness of adsorption is the surface area of an adsorbent.
To do so, adsorbent activation is needed to be applied, as well. This research was aimed to find
condition of optimum temperature and time in the activation process of natural zeolite physically.
The physical activation process of natural zeolite includes grinding natural zeolite using porcelain
mill and sifting it, so that it is similar in size to 100 mesh. And then heating it in a furnace with a
variable heating temperature of ± 200, 300, 400, 500 and 600 °C, meanwhile the variable of
heating time was set to 90, 135, 180, 225 and 270 minutes and then cooling it in the desiccator.
After that, the adsorption test on used cooking oil was held using the activated natural zeolite to
know the condition of optimal heating activation of temperature and time. The optimum conditions obtained in this study was ± 400 °C for the heating temperature and 225 minutes for the
heating time with a numeric value of free fatty acids amounting to 0,8138 % and saponification
value of the number amounting to 180.589 mg KOH/g.