Novel amphiphilic gemini ionic liquids based on consumed polyethylene terephthalate as demulsifiers for Arabian heavy crude oil

This work aims to use consumed polyethylene terephthalate (PET) to prepare new amphiphilic gemini ionic liquids (GILs). PET was converted into bis(2-hydroxyethylene) terephthalate (BHET). The produced BHET was reacted with thionyl chloride to produce the corresponding dialkyl halide, bis(2-chloroethyl) terephthalate (BCET). N,N-bis-hexaoxyethlene octadecylamine (HEOD) and N,N-bis-hexaoxyethlene dodecylamine (DOAD) were quaternized with BCET to produce the corresponding GILs: HEOD-IL and DOAD-IL, respectively. The chemical structures were confirmed by Fourier-transform infrared spectroscopy (FT-IR), H-1 nuclear magnetic resonance spectroscopy (H-1 NMR), and C-13 nuclear magnetic resonance spectroscopy (C-13 NMR). The surface tension, interfacial tension, and solubility were also investigated. In addition, the ability of the prepared amphiphilic GILs to demulsify Arabian heavy crude oil was evaluated. The results showed that their efficiency increased when the water content in the water-in-oil emulsion increased.