Process Economics Program Report 17/C
Published: June 2001
Acrylonitrile currently is commercially produced by the ammoxidation of propylene:
CH3CH=CH2 + NH3 + 1.5 O2 -> CH2=CHCN + 3 H2O
Acrylonitrile can also be produced by ammoxidation of propane:
CH3 CH2 CH3 + NH3 + 2 O2 -> CH2=CHCN + 4 H2O
Given the lower cost of propane relative to propylene, manufacturers have tried to develop catalysts for ammoxidation of propane directly to acrylonitrile. However, the lower conversion rates for propane ammoxidation have meant that the capital costs are higher than the costs for propylene-based processes. Lower conversions also meant lower yields and higher waste volumes, further reducing the potential cost advantage.
At the time of writing of this report, three companies (BP Nitriles Group [Sohio], Asahi Chemicals and Mitsubishi Chemicals) are in the process of commercializing propane-based processes for acrylonitrile.
Three propane-based processes are considered in this reports, the one based on BP/Sohio patents, one process based Mitsubishi patents and the process based on Asahi patents. Inclusion of a recycle into the processes based on Asahi or Mitsubishi patents is also considered.