How to simulate ethanol dehydration: reactor + separator written as one custom block
Bio-ethanol to ethylene (C₂H₅OH → C₂H₄ + H₂O), the route behind bio-based polyethylene, modeled as a single user-written custom block with two named inlets and two named outlets. The ethanol vapour feed and a dilution-water feed enter on the feed and water ports; the block's own equations convert 80% of the ethanol (xi = 0.8 * (feed.n_ethanol + water.n_ethanol)), send the ethylene and 10% of the water overhead on gas, and the condensed water with the unreacted ethanol out on liquid — a reactor and its quench separator in one model, which no fixed unit op is. Each outlet is flashed through Peng-Robinson at the temperature the model sets (330 K), and the block reports its mass balance: one mole of ethanol makes two moles of product, so moles are not conserved, but mass is, to round-off (46.07 = 28.05 + 18.02 g/mol). Edit the stoichiometry so it makes twice the ethylene and the block warns that the model creates mass. Notes: the 80% conversion and the 10%/5% overhead splits are stated by the model, not computed from kinetics or vapour-liquid equilibrium — this is a custom model a user writes when they have their own correlation, and it is exactly as good as that correlation.
- 1Open the ready-made model
Open the "Ethanol dehydration: reactor + separator written as one custom block" 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 ethanol, ethylene, water — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
- 3Review the flowsheet
The flowsheet chains Dehyd. 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
- ethanol, ethylene, water
- Unit operations
- Dehyd
Opens live on the canvas — free, no install.
Explore the model & flowsheetFrequently asked questions
- What does the Ethanol dehydration: reactor + separator written as one custom block model simulate?
- Bio-ethanol to ethylene (C₂H₅OH → C₂H₄ + H₂O), the route behind bio-based polyethylene, modeled as a single user-written custom block with two named inlets and two named outlets. The ethanol vapour feed and a dilution-water feed enter on the feed and water ports; the block's own equations convert 80% of the ethanol (xi = 0.8 * (feed.n_ethanol + water.n_ethanol)), send the ethylene and 10% of the water overhead on gas, and the condensed water with the unreacted ethanol out on liquid — a reactor and its quench separator in one model, which no fixed unit op is. Each outlet is flashed through Peng-Robinson at the temperature the model sets (330 K), and the block reports its mass balance: one mole of ethanol makes two moles of product, so moles are not conserved, but mass is, to round-off (46.07 = 28.05 + 18.02 g/mol). Edit the stoichiometry so it makes twice the ethylene and the block warns that the model creates mass. Notes: the 80% conversion and the 10%/5% overhead splits are stated by the model, not computed from kinetics or vapour-liquid equilibrium — this is a custom model a user writes when they have their own correlation, and it is exactly as good as that correlation.
- Which thermodynamic method does it use?
- The PENG-ROBINSON property package, over ethanol, ethylene, water — already selected. You can switch the method on the canvas before running.
- Which unit operations are in the flowsheet?
- It chains Dehyd. 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. Ethanol dehydration: reactor + separator written as one custom block 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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