Spectroscopic investigations to understand the enhanced dissolution of heavy crude oil in the presence of lactam, alkyl ammonium and hydroxyl ammonium based ionic liquids

Proposed mechanism for upgrading the dissolution of HCO in solvents in the presence of ILs. Dotted lines indicate the interaction between ILs and heteroatoms of asphaltene present in the HCO; green color represents the capro lactam ILs; orange color is the asphaltene/resin moiety of the HCO.