Organic Residual Hydrocarbon-Inorganic Mineral Affinity of Trace Elements and Their Influence on Coal-formed Hydrocarbon

In this paper, the organic affinity of residual hydrocarbon and trace elements in mid-rank coals from the Weibei coalfield of Shaanxi Province was examined by correlation analysis, and the authors put forward the concept of affinity coefficient. The results show that the distribution of trace elements in the Weibei coalfield shows obvious regularity among organic matters, minerals and various kinds of organic components. It is also shown that the correlation between trace elements and organic carbon/S1 is relatively weak in Weibei coalfield, which is different from things of the Junggar coalfield in Xinjiang. These characteristics result form various catalytic activities of trace elements in the process of hydrocarbon generation in different coal-formed environments, redistribution and remigration of trace elements among organic macromolecules during the condensation of aromatic compounds and abscission of function group in coal metamorphism, and selective adsorption of trace elements for different maturities of kerogens and different compositions of hydrocarbons.