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 achieved.
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 can not only extract phenol but also phenol-derived compounds
may be extracted from hydrocarbon oil.