Experimental and Modeling Studies of the Effects of Nanoclay on the Oil Behaviors in A Water-Sand System

When oil is spilled into the marine environment, a certain amount of spilled oil may finally reach the shoreline. This study comprehensively explored the effects of bentonite nanoclay on the oil behaviours in water-sand media from both experimental and modeling perspectives. Four factors including nanoclay concentration, temperature, salinity and pH have been studied. The increasing nanoclay concentration resulted in the decrease in remaining oil on sand. Higher temperature and salinity were associated with less residual oil on sand in the presence of nanoclay. The lower residudual oil on sand with coexisitng nanoclay was found to be at pH 7. The factorial analysis results indicated that the nanoclay concentration showed the most significant impact among these factors. Miscibility modeling resutls showed an increasing temperature was favorable to the nanoclay miscibility. Moreover, the effect of nanoclay on oil behaviro was further revealed through the dynamic simulation, in which it can be seen the nanoclay could penetrate into oil droplets and promote the detachment of oil from the solid substrate. The results of this study can help understand the role of fine particles in the fate and transport of oil on shoreline, and support the risk assessment and response planning after oil spill