Hydropyrolysis of pretreated high-boiling hydrocarbon fractions

Hydropyrolysis of different types of high-boiling hydrocarbon fractions (straight-run distillates of different boiling range, dearomatized fractions and a hydrocracked fraction) was studied and the results were compared with pyrolysis (steam cracking) carried out under similar operating conditions. In all cases, a substantial increase in the yield of ethylene, a total yield of olefins and a total yield of C-2 hydrocarbons, were observed. The possibility of limiting the amount of H2O by replacing it with H-2, CH4 or N-2, has been demonstrated. Hydropyrolysis was also shown to be effective in the case of a feedstock pretreated by dearomatization or hydrocracking. (C) 1997 Elsevier Science B.V.