The effects of dielectric materials on the petroleum oil removal from solid waste under microwave heating were fully detailed within this research. The experiments clearly show that although water has high dielectric properties, it is not efficient to remove heavy oils due to its volatility. Salt water having high loss factor contributes to the oil removal at low concentration, whereas high concentration results in less. Activated carbon was proved to be more efficient for either light or heavy petroleum oils. The simulation results yielded good estimations of power density throughout the sample. The simulated temperature distribution clearly explains the experimental results and can be used to predict the efficiency of organic removal from solid wastes. (c) 2011 Canadian Society for Chemical Engineering