Oxidative dehydrogenation of ethane to ethylene + acetic acid (EDHOX concept) — a PENG-ROBINSON process flowsheet
Linde's EDHOX technology co-produces ethylene AND acetic acid from ethane and oxygen in one catalytic step (a proprietary mixed-metal catalyst in a multi-tubular salt-cooled reactor), with combined ethylene+acetic-acid selectivity published above 93% and the CO₂ by-product of over-oxidation recovered pure (no nitrogen dilution, since the oxidant is pure O₂, not air). Modeled here as three chained fixed-conversion reactors on real, exactly mass-balanced reactions: the main dehydrogenation (C₂H₆ + 0.5 O₂ → C₂H₄ + H₂O), the acetic-acid co-production path (C₂H₆ + 1.5 O₂ → CH₃COOH + H₂O), and a minor full-oxidation loss path (C₂H₆ + 3.5 O₂ → 2 CO₂ + 3 H₂O) accounting for the un-selective balance — the same 'illustrative, not fitted' posture as the naphtha cracker's furnace, since Linde's catalyst kinetics are proprietary and not published. The per-reaction conversions here are tuned to reproduce the one real published number (>93% combined selectivity: this flowsheet computes ~96%), not an assumed per-pass ethane conversion, which Linde doesn't publish.
Modeling assumptions & limitations
- 1The acetic acid/water co-product is reported as one crude liquid stream (recovered via a simple cold knockout, ~98% of the acetic acid produced) — the real downstream acetic-acid/water dehydration column is not modeled, matching MaximaLabs's convention of disclosing every unmodeled downstream separation rather than implying a purity that wasn't computed.
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- Rigorous PENG-ROBINSON thermodynamics, solved by the same engine every simulation runs on.
- 4 unit operations modeled: MIX, 3× ODH COX, COOL, Knockout.
- Focus areas: EDHOX, Oxidative dehydrogenation, Ethylene, Acetic acid, CCUS.
- Thermodynamics
- PENG-ROBINSON
- Components
- ethane, ethylene, oxygen, acetic_acid, water, co2
- Unit operations
- MIX3× ODH COXCOOLKnockout
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Read the step-by-step guideReproduce 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("edhox-oxidative-dehydrogenation")
sim = client.create_simulation(example["title"], example["flowsheet"])
result = client.run_and_wait(sim["id"])
print(result["status"]) # "converged"
streams = client.streams(sim["id"])Related models
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