Oil Shale, 2015, Vol. 32, No. 3, pp. 240–251 ISSN 0208-189X doi: 10.3176/oil.2015.3.04 © 2015 Estonian Academy Publishers MICROWAVE-ASSISTED SOLVENT EXTRACTION OF SHALE OIL FROM JORDANIAN OIL SHALE SAMER I. AL-GHARABLI (a)* , MOHAMMED O. J. AZZAM (b) , MOHAMMAD AL-ADDOUS (c) (a) Department of Pharmaceutical and Chemical Engineering, German Jordanian University, Amman 11180 Jordan (b) Department of Chemical Engineering, Jordan University of Science & Technology, Irbid 22110, Jordan (c) Department of Energy Engineering, German Jordanian University, Amman 11180 Jordan Abstract. Oil shale as an alternative to oil is considered a major possible source of energy in Jordan which has an estimated 50 billion tons of geo- logical proven reserves that are widely distributed all over the country. Many methods have been used for extracting shale oil from oil shale. This investi- gation suggests the application of a novel technique, namely microwave- assisted extraction. Several solvents were tested for extractive capacity at different temperatures (50 to 140 C) by the microwave irradiation of the investigated oil shale. The extraction results showed that all the solvents except hexane followed a sigmoid behaviour. Methanol exhibited the highest extractive capacity of about 23% of shale oil. Several particle sizes in the range of 94–910 m were examined and the results indicated that shale oil extraction is not diffusion controlled. The dynamic effect of extraction was also considered and found to have a very little effect after 10 minutes of irradiation. Keywords: extraction, microwave, oil shale, shale oil, solvent. 1. Introduction It is well established that the world today is mostly dependent on fossil fuel as the major source of energy. It is also well realized that the world needs alternative sources for energy. Such sources include wind, solar, biofuels, geothermal and nuclear, to name some. One energy source that might be promising is oil shale as an alternative to oil. Oil shale (OS) is a layered sedimentary rock that contains abundant quantities of kerogen. The shale is mainly composed of calcium compounds * Corresponding author: e-mail samer.gharabli@gju.edu.jo