How to simulate propane dehydrogenation cold box
Propane dehydrogenation (PDH) to propylene over a Pt/Cr catalyst, followed by a cold-box separation recovering liquid propylene from the H₂-rich reactor off-gas, after US Patent 6,333,445 (Chart Inc., 2002). The refrigeration loop itself is not modeled — the cold box is represented here as a net cooling duty to condense the propylene, a bounded simplification. Unreacted propane recycle is not modeled either (reported as its own product stream).
Also known as: propane dehydrogenation, PDH unit, propylene from propane.
- 1Open the ready-made model
Open the "Propane dehydrogenation cold box" 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 propane, propylene, h2 — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
- 3Review the flowsheet
The flowsheet chains PDH, Coolbox, Flash. 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
- propane, propylene, h2
- Unit operations
- PDHCoolboxFlash
Opens live on the canvas — free, no install.
Explore the model & flowsheetFrequently asked questions
- What does the Propane dehydrogenation cold box model simulate?
- Propane dehydrogenation (PDH) to propylene over a Pt/Cr catalyst, followed by a cold-box separation recovering liquid propylene from the H₂-rich reactor off-gas, after US Patent 6,333,445 (Chart Inc., 2002). The refrigeration loop itself is not modeled — the cold box is represented here as a net cooling duty to condense the propylene, a bounded simplification. Unreacted propane recycle is not modeled either (reported as its own product stream).
- Is "Propane dehydrogenation cold box" the same as a propane dehydrogenation?
- Yes — this model covers what is also called propane dehydrogenation, PDH unit, propylene from propane. It runs the real process on the rigorous solver, so you can size and study it directly.
- Which thermodynamic method does it use?
- The PENG-ROBINSON property package, over propane, propylene, h2 — already selected. You can switch the method on the canvas before running.
- Which unit operations are in the flowsheet?
- It chains PDH, Coolbox, Flash. 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. Propane dehydrogenation cold box 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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