Novel synthesized polymeric surfactants additives based on phenethylamine as an emulsion breaker for water droplet coalescence in naturally Egyptian crude oil emulsion

Abstract

This work aims to prepare three non-ionic surfactants (DI, DII, and DIII) based on phenethylamine in different ratios of propylene oxide to ethylene oxide (PO/EO) in just two steps as novel polymeric additives to break down naturally crude oil emulsions. The first step was the propoxylation process followed by the ethoxylation process in the second step. FTIR, NMR, and mass spectroscopic techniques were used to validate their chemical composition, and gel permeation chromatography was used to determine their molecular weights. Their activities at the formation water/crude oil interface were inspected to study their adsorption by measuring the dynamic interfacial tension (IFT). Their relative solubility number (RSN), hydrophilic-hydrophobic balance (HLB), and partition coefficient (PC) were also assessed for the three prepared polymeric surfactants. The rheological properties of the dehydrated crude oil, untreated and treated crude oil emulsion were evaluated. The performance of synthesized polymeric emulsion breakers was reported at different concentrations. The demulsification mechanism was photoed using an optical polarizing microscope. Data of IFT, HLB, RSN, and PC participated in elucidating the demulsification performance of the prepared polymeric surfactants. This study showed that the highest coalescence rate of water droplets at 120 min and 500 ppm was achieved by DIII. Emulsion viscosity was reduced by as much as one order of magnitude and reached the oil viscosity in the presence of the DIII. The demulsifying mechanism was observed to go through three phases: adsorption & flocculation, coalescence & the creation of a channel, and separation.