Absorption Process of Expanded Graphite

Different expansion volume of expanded graphite was used for oil absorption experiments. The structure of expanded graphite was studied by scanning electron microscope (SEM) and optical microscope before oil-absorption and after oil-absorption. It was found that viscosity, expansion volume and particle size are the three key factors for the higher absorption capacity. But under the lower expansion volume and particle size, absorption capacity is not irregular. It shows that adsorption capacity is related to the pore structure. The more reasonable that pore structure is, the more expanded graphite can contain of the oil. In addition, the absorption rate is relevant to the contact area and viscosity of oil.