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Aniline plant, Baton Rouge, Louisiana, USA

Ammonolysis of phenol to aniline — a PENG-ROBINSON process flowsheet

Vapor-phase ammonolysis of phenol with excess ammonia to aniline plus water, per Figure 20.2 (p. 366) of Synthetic Nitrogen Products by Gary R. Maxwell (Kluwer, 2004). Unreacted ammonia and product water are let down to atmospheric and knocked out, then a column recovers the aniline. Phenol (bp 455 K) is very slightly MORE volatile than aniline (bp 457 K), so the aniline leaves as the bottoms and the residual water/ammonia plus the unreacted phenol go overhead.

Modeling assumptions & limitations

  1. 12 K apart is a genuinely hard split — the aniline product comes out ~86 mol%, carrying ~14 mol% phenol, at ~91% recovery. A sharper cut is a much taller column, not a tuning change, and Peng-Robinson carries no aniline/phenol association to sharpen it.

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Phenol FEED
NH3 FEED
MIX
Reactor
COOL
Flash
NH3 Water VENT
feed
dist
btms
Qc
Qr
COL
WET Light ENDS
Aniline Product
What this showcases
  • Rigorous PENG-ROBINSON thermodynamics, solved by the same engine every simulation runs on.
  • 5 unit operations modeled: MIX, Reactor, COOL, Flash, COL.
  • Focus areas: Ammonolysis, Amines, Nitrogen chemistry.
Specification
Thermodynamics
PENG-ROBINSON
Components
phenol, ammonia, aniline, water
Unit operations
MIXReactorCOOLFlashCOL
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Python SDK

Reproduce this exact result from Python — the real client.get_example() → run_and_wait() path, not a mockup.

from flowsim.sdk import FlowSimClient

client = FlowSimClient()
example = client.get_example("aniline-from-phenol")
sim = client.create_simulation(example["title"], example["flowsheet"])
result = client.run_and_wait(sim["id"])

print(result["status"])              # "converged"
streams = client.streams(sim["id"])

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