Typical FCC reactor conditions: Industrial catalytic cracking (e.g., FCC) commonly operates near which pressure–temperature combination?

Introduction:
Catalytic cracking (especially FCC) converts heavy gas oils to gasoline and lighter products using a solid acid catalyst at elevated temperature and modest pressure. Choosing realistic operating ranges helps distinguish FCC from hydrocracking and thermal processes.

Given Data / Assumptions:

• Atmospheric to a few atmospheres pressure in FCC riser/regen loop.
• Reaction temperatures roughly around 480–540°C in the riser.

Concept / Approach:
FCC employs short contact times at high temperature and low–moderate pressure to favour gasoline-range products while minimising overcracking and coking. Pressures above ~3–4 atm are unusual in classic FCC risers, and temperatures near 200°C or 750°C are out of range for the cracking step.

Step-by-Step Solution:

Verification / Alternative check:
Process descriptions consistently cite ~1–3 atm riser pressure and ~500°C reactor outlet temperatures.

Why Other Options Are Wrong:

• 10 atm at 500°C: More characteristic of hydroprocessing with hydrogen, not FCC.
• 30 atm & 200°C / 50 atm & 750°C: Out of FCC envelope.
• 1 atm & 350°C: Temperature too low for effective catalytic cracking.

Common Pitfalls:
Mixing FCC with hydrocracking conditions where high H2 pressure is used.

Final Answer:
2 atm & 500°C