The structure and reactivity of a low-sulfur lacustrine oil shale (Colorado U.S.A.) compared with those of a high-sulfur marine oil shale (Julia Creek, Queensland, Australia)

Recovery of shale oil condensate from different oil shales using a flow-through apparatus

“…For sealed autoclave reactions under N 2 at 390°C, there was an increase in oil+H 2 O yield with time for both oil shales and a bigger increase for Julia Creek than for Colorado [16]. However, it is not generally true that the effect of time is greater for the Julia Creek than for the Colorado shale because for sealed autoclave reactions under H 2 at 390°C, the increase in oil+H 2 O yield with time was bigger for Colorado than for Julia Creek [16]. The gas yields for the sealed autoclave reactions at 390°C were generally less than 1 wt.% db (unpublished work) and so will not affect the general features of the effect of time.…”

“…It was of lacustrine origin, deposited in a shallow brackish lake [22] and of Eocene age [23] (56.0-33.9 Ma [21]). Detailed analyses of these oil shales have been given in Amer et al [8,16]. All of these oil shales were highly aliphatic, with f a values varying from 0.12 for the Colorado oil shale to 0.18 for Yarmouk, 0.21 for El-Lajjun and 0.28 for Julia Creek [7,8,16].…”

“…Initially, the back (N 2 ) pressure was set at 3 MPa, the same as the cold gas pressure used in earlier autoclave runs [7,8,16]. The sweep gas flow rate was set at 75 ml/min.…”

“…For the Julia Creek and Colorado oil shales, the Fischer Assay oil yield was much higher than the condensate yield at 425°C. For these two oil shales, yields of useful products were still changing significantly between 390°C and 425°C [16] so that further increases in going to 500°C might be expected. Another factor that may have had some influence was that flow-through conditions were optimized for the El-Lajjun oil shale and the optimum conditions may be different for other oil shales.…”

“…It would therefore be useful to compare the two approaches and investigate the differences and similarities in the yield and composition of the products. In this study four oil shales, including two from Jordan, which had been previously reacted in sealed autoclaves [8,16] were reacted in flow-through experiments under conditions as similar as possible to those used for the earlier autoclave experiments.…”