Abstract: The adsorption property of natural kaolin for oil field wastewater was investigated.The results indicated that when Kaolin dose was 10 g/L with stirring speed of 250 r/min and adsorption time of 30 min at room temperature (25 ℃) and the normal pH value (8)，the removal rate of crude oil with Kaolin can reach more than 80% when oil concentration in oil field wastewater is less than 1 350 mg/L.The overall adsorption process with Kaolin from oil field wastewater was spontaneous endothermic process.The isothermal data could be well described by the Langmuir equation.The dynamical data fit well with the pseudo-second-order kinetic model.

Key words: Kaolin, Oil field wastewater, Adsorption, Kinetics, Termodynamics