Evaluation of triethanolamine‐cashew nutshell liquid derivatives as crude oil emulsion breakers

Abstract

Three bio-based crude oil emulsion breakers have been prepared from agricultural waste by chemical treatment of cashew nutshell liquid (CNSL) extract with triethanolamine via a one-pot reaction at 120 ℃. The triethanolamine-ester derivatives were characterized by Fourier Transform-InfraRed spectroscopy. Their effectiveness as crude oil emulsion breakers were investigated experimentally using the bottle test method. The effect of solvent type, water content, and concentration of the emulsion breaker, was used to study the demulsification process and determine their demulsification efficiency at a temperature of 60 ℃ for a contact time of 180 min. A commercial demulsifier, PhaseTreat 4633 (PT-4633) was used as a benchmark. Performance evaluation of the prepared emulsion breakers revealed their effectiveness in descending order as: triethanolamine dianacardate (TED) > triethanolamine trianacardate (TET) > triethanolamine anacardate (TEA). The data reveals that their emulsion breaking efficiency increases with increasing emulsion water content, and concentration. PT-4633 exhibited better demulsification efficiency than the triethanolamine-esters in xylene across the concentration and water content studied. Improved water separation was however observed for the triethanolamine-esters in butanol, as triethanolamine trianacardate (TET) performed better than PT-4633 at 10 ppm to 20 ppm at 30% water content with a water separation of 83.33% and 80% respectively. The evaluated triethanolamine ester derivatives exhibited better emulsion breaking potentials in butanol than xylene at shorter times, which may be due to the synergistic effect of butanol. Therefore, butanol could be used as a sustainable solvent substitute for xylene in demulsifier formulations.