THermal tolerance and compatibility of NaOH−Poly(vinyl alcohol) in Bitumen emulsification for improved flow properties

Poly(vinyl alcohol) (PVA) is often used to reduce the viscosity of bitumen. Although some studies have investigated the effects of the emulsification conditions, including aqueous phase salinity, on the performance of PVA, the tolerance to thermal degradation and compatibility with other additives, including alkaline solutions, have not been studied. Therefore, to increase the applicability of this technique, batch emulsification experiments were performed to investigate the thermal degradation tolerance and compatibility with ethanol−NaOH solution. Bitumen was emulsified using the heated samples of PVA. Different bitumen samples were also emulsified using the mixture of PVA and NaOH in the presence of ethanol. Evaluation of the particle sizes of the emulsions confirmed that PVA could be reliably applied between ambient temperature and 200 °C. In addition, evaluation of the apparent viscosity and stability of each bitumen emulsion produced showed that the mixture of PVA and ethanol−NaOH had a synergistic effect on formation of stable oil-in-water emulsions with increased reduction in the viscosity. With the decrease in viscosity, a large decrease in the power required for pumping of the fluid was observed in flow simulation.