Propylene Basics

Propylene (CH3-CH=CH2) is

• The second largest volume building block for many petrochemicals
• End products such as plastics, resins, fibers, solvents, polyurethanes, etc.
• Colorless, flammable gas and practically odorless
• A very reactive intermediate and, therefore, is involved in many chemical reactions
  • Polymerization for the production of polypropylene
  • Cumene through benzene alkylation
  • Acrylonitrile by ammoxidation
  • Propylene oxide via chlorohydrin chemistry or peroxidation
  • Alcohols via hydration
  • Acrylic acid via oxidation
• Acts as a mild anesthetic
• Plants emit a small amount of propylene naturally

Propylene manufacturing

• By-product (also referred to as co-product) of the thermal cracking process for ethylene production
• By-product from the refinery Fluid Catalytic Cracking (FCC), including high-severity, units
• On-purpose propylene production via
  • Propane dehydrogenation
  • Methanol to propylene and/or ethylene
  • Metathesis process
  • Olefins interconversion processes
• Propane dehydrogenation processes
  • Reactor section – fixed bed or continuous catalyst regeneration system
    • Once through conversion of propane is limited
    • Platinum or Chromium-based
  • Recovery Section
    • Including reactor effluent compressor, lights recovery, propane/propylene separation

Alternate Routes for Propylene Production
These technologies are potential options for propylene production.

1. Catalytic pyrolysis process (based on a combination of carbonium and free radical mechanisms) for production of propylene (and light olefins) using heavy hydrocarbon feeds. This process has been used in commercial applications in China.
2. Propane dehydrogenation process based on chemical looping concept – currently under development
3. Fluid solids cracking processes – currently under development
4. Bio-propylene routes – currently under development