How to simulate ammonia cracking + h2 purification
Green ammonia is a widely proposed hydrogen *carrier* for shipping — easier to liquefy and transport than liquid H₂ itself, then cracked back to H₂ at the point of use. A fixed-conversion reactor dissociates NH₃ (2 NH₃ → N₂ + 3 H₂, endothermic, 99% conversion at a typical 600 C cracking-furnace outlet) and the cracked gas is polished by an adsorption stage to fuel-cell-grade H₂.
- 1Open the ready-made model
Open the "Ammonia cracking + H2 purification" 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 ammonia, n2, h2 — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
- 3Review the flowsheet
The flowsheet chains Cracker, PSA. 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
- ammonia, n2, h2
- Unit operations
- CrackerPSA
Opens live on the canvas — free, no install.
Explore the model & flowsheetModeling assumptions & limitations
What this model captures, and what it deliberately does not — from the engineers who built it.
- 1This models the adsorption stage as a single equilibrium Langmuir contact (competitive isotherm, H₂ weakly adsorbed vs. N₂/NH₃ strongly adsorbed) — a real PSA's cyclic pressure-swing/purge steps aren't modeled, only the equilibrium separation a cycle is built around. A true gas-phase membrane stage was left out for the same reason: the solver's `membrane` unit op is a liquid reverse-osmosis model (osmotic-pressure driven), not a gas-permeation membrane, so it doesn't apply here.
Frequently asked questions
- What does the Ammonia cracking + H2 purification model simulate?
- Green ammonia is a widely proposed hydrogen *carrier* for shipping — easier to liquefy and transport than liquid H₂ itself, then cracked back to H₂ at the point of use. A fixed-conversion reactor dissociates NH₃ (2 NH₃ → N₂ + 3 H₂, endothermic, 99% conversion at a typical 600 C cracking-furnace outlet) and the cracked gas is polished by an adsorption stage to fuel-cell-grade H₂.
- Which thermodynamic method does it use?
- The PENG-ROBINSON property package, over ammonia, n2, h2 — already selected. You can switch the method on the canvas before running.
- Which unit operations are in the flowsheet?
- It chains Cracker, PSA. 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. Ammonia cracking + H2 purification 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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