Characterization of oil-in-water microemulsions based on ethoxylated surfactant for paraffinic deposits removal

•Prospective oil-in-water microemulsions were obtained for paraffin removal.•Stable single phase microemulsions were obtained with different oil components.•Paraffin solubilization alters the rheological behavior of microemulsions from Newtonian to Bingham.•Despite oil-in-water, the microemulsions systems obtained show excellent wettability in solid paraffin. Paraffin deposition is still a challenge in the oil industry and could be extremely costly until reaching the production stop. Microemulsions are surfactant-based systems able to prevent or remediate paraffin deposition. This work reports the characterization of an oil-in-water (O/W) microemulsion system (ME) with the potential for removing paraffinic deposits. The systems were characterized regarding phase equilibrium, droplet size, and rheology for three different phase oil components: kerosene, xylene, and Diesel. Moreover, fluid–solid interaction experiments were performed in order to evaluate the capacity of solubilization and understand how the rheological behavior is modified after paraffin solubilization. The O/W microemulsion prepared under different compositions tends to form Winsor-IV with particle size varying from 2.9 up to 56.7 nm. Wettability between the paraffin and microemulsion tends to increase with time, being completely spread for some of the systems obtained. A content of 5 % wt. of paraffin on the microemulsion system does not alter the phase equilibrium and the rheology behavior. We observe a slight alteration in the absolute viscosity values, between 10 and 60 °C, but not affecting flow assurance conditions.