Removal of Phenol from Organic System by Using Ionic Liquids

Abstract

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. 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. The study demonstrates the selective removal of phenol from petroleum oil using ionic liquids is a simple and environmentally friendly process for industrial use. This method cannot only extract phenol but also phenol-derived compounds may be extracted from hydrocarbon oil.