2. Experimental
2.1. Materials used
Waste lubricant oils were gathered at collecting stations in the
city of Mosul (Iraq). The samples were homogenized, getting enough
oil to conduct the research, and, next, transferred to an
appropriate tank, stored away from light and at room temperature
for several days to allow large suspended particles to settle under
gravity.
Solvents used for extraction were n-hexane, 1-butanol, petroleum
ether, 1-hexanol, carbon tetrachloride and acetone. The solvents
were of analytical grade and supplied by BDH.
Adsorbents used were almond shell, walnut shell, eggshell, and
activated clay – which was prepared locally. Sorbents (almond
shell, walnut shell, eggshell) of particle size 30–60 mesh were
used, while activated clay of 100–230 mesh size were tested.