Objective: Selective removal of phenol from organic solvent mixture (benzene
+ toluene + hexane) or other petroleum by-products have a major concern. Hence,
the experiments were conducted on the removal of phenol from synthetically prepared
phenolic organic waste by using a green process, ionic liquids.
Methods: The ionic liquids, 1-ethyl-3-methyl imidazolium cyanoborohydride, and 1-
butyl-3-methyl imidazolium hexafluorophosphate were used for the extraction study.
The effect of various operating parameters such as the type of ionic liquids, effluent
temperature, extraction time, and the phase volume ratio of ionic liquid and phenol has
been studied in details. The ionic liquid, 1-ethyl-3-methyl imidazolium cyanoborohydride
selectively extracted 95 % of the phenol from the synthetically prepared organic
oil mixture of benzene and toluene, with an initial phenol concentration was 100 ppm.
Further, ionic liquids were recycled and reused for six consecutive studies with removal
efficiency of about 74%. Additionally, a batch reactor study was conducted to find
the process viability for industrial use and 92% phenol removal efficiency was
Results: The study demonstrates the selective removal of phenol from petroleum oil
using ionic liquids is a simple and environmentally friendly process for industrial use.
Conclusion: This method cannot only extract phenol but also phenol-derived compounds
may be extracted from hydrocarbon oil.