Effects of Flow Improver Additives on Distillate Fuels from Oil Shale

The ability of additives to improve the cold flow properties of shale oil distillates boiling in the diesel fuel range was evaluated using hydrotreated shale oils as model fuels. Crude oil shale from Occidental Oil Shale Company was fractionated to give three liquids in the diesel fuel boiling range. Each fraction was hydrotreated to three different severities to afford 9 different model fuels. A variety of commercial and experimental additives were evaluated as cold flow improvers in these fuels as treat levels of 0.04-0.4 wt. %. Both the standard pour point test (ASTM D97) and a more severe low temperature flow test were employed. Reductions in pour points of from 0-70°F and improvements in a low temperature flow test from 0-16°F were achieved. It is concluded that flow improver additives can play an important role in improving the cold flow properties of future synthetic fuels of the diesel type derived from oil shale.