The Effect of Nano-Silica Modified With Silane Coupling Agents on the Diffusion Behavior of Water Molecules in Palm Oil Based on Molecular Simulation

To enhance the compatibility of nano-SiO2 and palm oil, four different types of silane coupling agent (KH550, KH560, KH570 and KH792) were adopted to modify the surface of silica. It turns out that when using the KH792 to modify the surface of nano-SiO2, the interfacial bonding between silica and palm oil was maximum and their overlapping area was the largest, up to 12 Å. Thus, it can be concluded that the relatively optimal silane coupling agent is KH792. And when nano-SiO2, whose surface was modified with KH792, was added to the palm oil, the interaction energy between palm oil and water molecules was enhanced and the diffusibility of water molecules in oil was decreased. In addition, the addition of nano-SiO2 to the oil reduced the diffusible space of water molecules provided by oil and further restricted the diffusion of water molecules in oil. Therefore, it can be seen that the addition of nano-SiO2 to palm oil may cause the restriction of the diffusion of water molecules in it