| Oil has become one of the global environmental pollutants due to its universality in water and high toxicity risk to human beings.Marine sediments are a main approach of transformation and transportation of oil. It is very important to study the sorption of oil on marine sediments from the practical points of view of the oceanic and environmental science.Recent studies show that expanded graphite is an interesting sorbent material for removing oil spills quickly from water, with high capacitiy due to its specific pore characteristic. It is a prospective environment-protection material with the advantage of cheap price and excellent effect.In this thesis the parameters of sorption kinetics and thermodynamics of heavy oil on sediment and expanded graphite are studied in the medium of 3.5% of NaCl solution. Furthermore, the effects of other environmental factors such as temperatures(283K, 288K, 293K, 298K), pH(6, 7, 8), concentrations of NaCl (1.77%, 2.33%, 3.5%) are also investigated. The main results are as follows:1) The sorption kinetic process of heavy oil on both sediments and expanded graphite has been proven to follow the Lagergren-pesudo-second-order kinetic rate equation;2) The experiments indicate that the sorption isotherms of heavy oil on sediment can be described by the Freundlich isotherm, while that on expanded graphite can be described by the Langmuir, Freundlich and the multilayer sorption isotherms.3) The sorption thermodynamic parameters are calculated in the temperature ranges of 283K-298K. The parameters(ΔH0,ΔG0,ΔS0)are all negative for sorption of heavy oil on both sediment and expanded graphite..4) The sorption capability is increased under higher concentration of NaCl, lower pH and decreased temperatures for the sorption of heavy oil on sediment.As for expanded graphite, the sorption capability increases with decreased temperature and lower concentration of NaCl; in addition ,the sorption capability at pH=7 is higher than that at pH=6 and pH=8.
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