Oil samples

obtained by retorting Indonesian oil sands at different end temperatures

were analyzed by 1H nuclear magnetic resonance spectroscopy and elemental analyzer.Based on the assignments of hydrogen peaks

integrating each 1H NMR peak can give hydrogen distribution in oil samples.The average structure parameters were calculated using modified Brown-Ladner method.The influence of retorting end temperature on chemical structure of the oil-sands oil could be revealed from an analysis for change tendency of structure parameters with retorting end temperature.The results showed that

with increasing end temperature

the chemical structure of oil-sands oil changed significantly

i.e.

the number of aliphatic carbons Cal

aromatic peripheral carbons Cp(us)

aromatic carbons Ca(us)

aromatic rings Ra(us)

naphthenic rings Rn(us) and total rings Rt(us) all decreasing

mainly due to decomposition of alkanes

broken of alkyl side chains

condensation of aromatic and naphthenic rings and ring-opening.Owing to the different of oil constituents produced and that of influence degree of distillation-pyrolysis

average mass of unit structure and average relative molecular weight decrease first and then increase with rise of retorting end temperature.