The fusion of oil shales with eutectic mixtures of inorganic salts was studied with the objective of finding a chemical means of releasing the organic material either at a lower temperature or with a lower empirical activation energy (E/sub a/). Experimental techniques by which the pyrolysis of oil shale was studied were thermogravimetry (TG), evolved gas detection (EGD), and pyrolysis/thin-layer chromatography (TLC). The following fused salts were investigated (ratios in mol%): LiCO sub 3 /Na sub 2 CO sub 3 /K sub 2 CO sub 3 , 43.5/31.5/25.0; KSCN/NaSCN, 73.75/26.25; KSCN/NaSCN, 70/31;Na sub 2 SO sub 4 /K sub 2 SO sub 4 /ZnSO sub 4 , 29.1/30.2/40.7; NaCl/Na sub 2 CO sub 3 /NaOH, 7.8/6.4/85.8; and K sub 2 CrO sub 4 /KOH/LiOH, 6/69/25. The last two mixtures were extremely difficult to handle and were unsuitable for use in oil-shale pyrolyses. Of the others, only the carbonate eutectic showed any difference in pyrolysis of oil shale with the fused salt as compared with pyrolysis of the oil shale alone. For a 50 gallon-per-ton (gpt) oil shale, this eutectic effected increased product evolution only above 675 exp 0 C; however, for a 22-gpt oil shale, increased product release was observed starting at about 400 exp 0 C. These results are thought to be due to differences in the mineral content of the shales. (ERA citation 03:030328)
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