CHARACTERIZATION OF KEROGEN FROM TIMAHDIT SHALE (Y-LAYER) BASED ON MULTISTAGE ALKALINE PERMANGANATE DEGRADATION

A 15-step alkaline permanganate degradation of the kerogen from Moroccan Timahdit Oil Shale (Y-layer) was carried out. Oxidation products were obtained in a good yield (64 wt% based on initial kerogen). Detailed g.c. and g.c.-m.s. analyses of ether- and water-soluble acids and products of further controlled permanganate degradation of precipitated acids served as a basis for the quantitative estimation of the contributions of various types of products and for comparison with other kerogens. Taking into account the dominant aliphatic (44.2%) and aromatic (34.8%) nature of the acidic oxidation products, the existence of an aliphatic cross-linked nucleus mixed with cross-linked aromatic units in the Timahdit-Y shale kerogen is postulated. These findings were corroborated by FT-i.r. and C-13 CP-MAS n.m.r. analyses. Saturated hydrocarbons were also found in the oxidation products; they were probable trapped in the kerogen matrix.