Mode of occurrences of trace elements in oil shale

The occurrences of trace elements in Fushun, Longkou and Maoming oil shale samples were determined using float-sink test and demineralization. The results of float sink test are consistent with that from demineralization. Most trace elements occur in inorganic mineral, but there are still some differences among the 3 oil shales. The trace elements of V, Mn, Zn, Sr, Mo, Ta, Cd are found in the samples. Cr, Te in Fushun, Cd, Sn in Longkou, and Cd, Sn, Pb in Maoming are primarily associated with mineral matters. The trace elements of Cr, Te in Maoming, Cd in Fushun, and Pb in Longkou oil shale samples are primarily associated with organic mineral. Part of Co, Sn, Pb in Fushun, Co in Longkou and Maoming oil shale samples are associated with organic mineral, while most of them are associated with clay mineral.