Laboratory tests of the CHESS process were conducted using beneficiate
d Alabama oil shale and regenerable catalysts at 500 degrees C and 7 M
Pa with 20 min shale residence time. Product oil sulfur and nitrogen c
ontents were reduced by up to 98 and 74% respectively, compared with u
ncatalysed pressurized fluidized-bed hydroretorting (PFH). Operation w
ith the catalysts reduced the density of the oil by 10% to 0.909 g cm(
-3) while still achieving 200% Fischer assay oil yield.