How to simulate chiral api purification: continuous smb chromatography
A racemic active pharmaceutical ingredient (R/S enantiomers, dilute in ethanol eluent) is resolved continuously by simulated moving bed chromatography — the workhorse of chiral-drug manufacture that legacy steady-state flowsheet simulators have no native model for (engineers script it in MATLAB). This uses the native SMB unit op, which solves the standard steady-state True Moving Bed equivalent: a 4-zone counter-current equilibrium-stage cascade whose zone flow-rate ratios sit inside the triangle-theory separation region, so the more-retained enantiomer reports to the extract and the other to the raffinate — the separation is driven by the chiral adsorption selectivity (the two enantiomers are otherwise thermodynamically identical).
- 1Open the ready-made model
Open the "Chiral API purification: continuous SMB chromatography" 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 r_ibuprofen, s_ibuprofen, ethanol — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
- 3Review the flowsheet
The flowsheet chains SMB. 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
- r_ibuprofen, s_ibuprofen, ethanol
- Unit operations
- SMB
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 is the TMB steady-state equivalent, not the transient multi-column process with discrete port switching; stages are ideal equilibrium stages (no mass-transfer resistance / axial dispersion); the isotherm affinities are illustrative screening values.
Frequently asked questions
- What does the Chiral API purification: continuous SMB chromatography model simulate?
- A racemic active pharmaceutical ingredient (R/S enantiomers, dilute in ethanol eluent) is resolved continuously by simulated moving bed chromatography — the workhorse of chiral-drug manufacture that legacy steady-state flowsheet simulators have no native model for (engineers script it in MATLAB). This uses the native SMB unit op, which solves the standard steady-state True Moving Bed equivalent: a 4-zone counter-current equilibrium-stage cascade whose zone flow-rate ratios sit inside the triangle-theory separation region, so the more-retained enantiomer reports to the extract and the other to the raffinate — the separation is driven by the chiral adsorption selectivity (the two enantiomers are otherwise thermodynamically identical).
- Which thermodynamic method does it use?
- The PENG-ROBINSON property package, over r_ibuprofen, s_ibuprofen, ethanol — already selected. You can switch the method on the canvas before running.
- Which unit operations are in the flowsheet?
- It chains SMB. 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. Chiral API purification: continuous SMB chromatography 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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