How to simulate oxidative dehydrogenation of ethane to ethylene + acetic acid (edhox concept)
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. Honesty note: the 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 this codebase's convention of disclosing every unmodeled downstream separation rather than implying a purity that wasn't computed.
- 1Open the ready-made model
Open the "Oxidative dehydrogenation of ethane to ethylene + acetic acid (EDHOX concept)" model in the MaximaLabs workspace — no install, no license. It loads live on the canvas, ready to edit and run.
- 2Confirm the thermodynamics
This process is modeled with the PENG-ROBINSON property package over ethane, ethylene, oxygen, acetic_acid, water, co2 — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
- 3Review the flowsheet
The flowsheet chains MIX, 3× ODH COX, COOL, Knockout. Every block is a real, solvable unit op you can reconfigure on the canvas.
- 4Run the simulation
Click Run. The deterministic solver converges the material and energy balances (recycles included) and fills the live stream table — the AI never invents a number.
- 5Read the results and iterate
Inspect the converged streams, tweak a spec, and re-run — or ask the AI copilot to explain a result or diagnose a failed solve in plain English.
- Thermodynamics
- PENG-ROBINSON
- Components
- ethane, ethylene, oxygen, acetic_acid, water, co2
- Unit operations
- MIX3× ODH COXCOOLKnockout
Opens live on the canvas — free, no install.
Explore the model & flowsheetFrequently asked questions
- What does the Oxidative dehydrogenation of ethane to ethylene + acetic acid (EDHOX concept) model simulate?
- 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. Honesty note: the 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 this codebase's convention of disclosing every unmodeled downstream separation rather than implying a purity that wasn't computed.
- Which thermodynamic method does it use?
- The PENG-ROBINSON property package, over ethane, ethylene, oxygen, acetic_acid, water, co2 — already selected. You can switch the method on the canvas before running.
- Which unit operations are in the flowsheet?
- It chains MIX, 3× ODH COX, COOL, Knockout. Every block is a real, solvable unit operation you can reconfigure, add to, or remove.
- Do I need to install software or buy a license?
- No. Oxidative dehydrogenation of ethane to ethylene + acetic acid (EDHOX concept) runs entirely in your browser on MaximaLabs — free, no install, no license. Open the model to load it live and run the deterministic solver.
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