Study on Geochemical Occurrences of REE in Wangqing Oil Shale

Abstract

Sequential chemical extraction experiment (SCEE) and Float- sink experiment (FSE) have been employed on oil shale research from Wangqing, Jilin province China, in order to determine the binding forms of rare earth elements (REE) in oil shale. The REE contents were determined by the inductively coupled plasma-mass spectrometry (ICP-MS). Wangqing oil shale was screened into specific gravity density level: <1.5g/cm³, 1.5–1.6g/cm³, 1.6–2.0g/cm³, 2.0–2.4g/cm³, >2.4g/cm³. The mode of occurrences of rare earth elements in Wangqing oil shale was studied by six-step SCEE. FSE results show that REEs in Wangqing oil shale exist mainly in inorganic minerals and more in excluded mineral, while SCEE results show that REEs of Wangqing oil shale is primarily occurred in minerals, including carbonate, Fe-Mn oxide, sulfide, and Si-minerals. FSE and SCEE results fully illustrate excluded mineral is mainly mode of occurrence of REEs in Wangqing oil shale, whereas inorganic minerals and organic matter is not that. The REE distribution pattern curves of FSE density and SCEE fraction products are similar with that of raw oil shale. The REE in different densities products has a close connection with terrigenous clastic rock, and the supply of terrestrial material is stable.