One exemplary embodiment can be an apparatus for treating a hydrocarbon stream having one or more compounds with a boiling point of about 140° to about 450° C. The apparatus can include an extraction zone and a regeneration zone. The extraction zone can include at least one settler. Each settler can have a height and a length. Typically the length is greater than the height. Also, the settler can form a boot, which can be adapted to receive a feed at one end. The regeneration zone may include a regenerator for an ionic liquid. The regenerator can include a column adapted to provide a regenerated ionic liquid to the extraction zone.