Treatment of Petrochemical Pyrolysis Gasoline (PG) Using Novel Eco-friendly Choline Chloride-based Deep Eutectic Solvents (DESs)

Document Type : Research Paper


Department of Physical Chemistry, University of Tabriz, Tabriz, Iran


To compare the performance of conventional solvent (N-formylmorpholine or NFM) with deep eutectic solvents (DESs) for benzene extraction, some (choline chloride : ethanolamines) based DESs were selected as extraction solvents. Liquid – Liquid extraction measurements were conducted on a petrochemical cut (pyrolysis gasoline) as feedstock. The influence of the solvent to feed ratio, temperature and extraction time on the (pyrolysis gasoline + NFM or DES) mixtures were investigated. Moreover, the selectivity (S) and solute distribution coefficient (β) were determined for the studied conventional solvent and DESs. Results show that the benzene extraction performance using one of the deep eutectic solvents (choline chloride: monoethanolamine with (1:5) mole ratio) is better than that of the conventional extraction solvent (NFM) at the studied conditions. In addition, lower contamination of extracted benzene (with NFM and other extractors) and immiscibility of DES in the hydrocarbon phase (NFM is partially miscible in the hydrocarbon phase) are among other advantages of this replacement.


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