How to simulate styrene monomer via ethylbenzene dehydrogenation
Ethylbenzene dehydrogenates over an equilibrium/conversion reactor to styrene monomer plus hydrogen — the endothermic reaction that supplies the world's polystyrene/SBR-rubber feedstock. A downstream column recovers unreacted ethylbenzene overhead for recycle while polymer-grade styrene leaves the bottoms. Vasudevan design, Ind. Eng. Chem. Res. 2009, 48, 10941 (Figure 15.1).
Also known as: styrene monomer unit, ethylbenzene dehydrogenation, SM plant.
- 1Open the ready-made model
Open the "Styrene monomer via ethylbenzene dehydrogenation" 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 ethylbenzene, styrene, h2 — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
- 3Review the flowsheet
The flowsheet chains RXN, SEP, COL. 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
- ethylbenzene, styrene, h2
- Unit operations
- RXNSEPCOL
Opens live on the canvas — free, no install.
Explore the model & flowsheetFrequently asked questions
- What does the Styrene monomer via ethylbenzene dehydrogenation model simulate?
- Ethylbenzene dehydrogenates over an equilibrium/conversion reactor to styrene monomer plus hydrogen — the endothermic reaction that supplies the world's polystyrene/SBR-rubber feedstock. A downstream column recovers unreacted ethylbenzene overhead for recycle while polymer-grade styrene leaves the bottoms. Vasudevan design, Ind. Eng. Chem. Res. 2009, 48, 10941 (Figure 15.1).
- Is "Styrene monomer via ethylbenzene dehydrogenation" the same as a styrene monomer unit?
- Yes — this model covers what is also called styrene monomer unit, ethylbenzene dehydrogenation, SM plant. 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 ethylbenzene, styrene, h2 — already selected. You can switch the method on the canvas before running.
- Which unit operations are in the flowsheet?
- It chains RXN, SEP, COL. 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. Styrene monomer via ethylbenzene dehydrogenation runs entirely in your browser on MaximaLabs — free, no install, no license. Open the model to load it live and run the deterministic solver.
More guides like this
Integrated styrene chain: benzene to styrene monomer
The full two-step styrene chain connected as one flowsheet rather than two standalone process snippets: benzene alkylated with ethylene to ethylbenzene, purified in a recovery column, then fed directly to the dehydrogenation reactor that makes styrene monomer. The unreacted ethylbenzene the dehydrogenation column recovers is reported as its own product stream rather than recycled back onto the alkylation feed (an honest simplification — closing that loop needs a torn-recycle edge back into ALKCOL, which the plant does but this flowsheet does not).
LOHC hydrogen release (methylcyclohexane dehydrogenation)
A liquid organic hydrogen carrier (LOHC) power train: methylcyclohexane (MCH) is preheated and catalytically dehydrogenated (MCH → toluene + 3H2, endothermic, equilibrium-limited to ~90% single-pass conversion) to release hydrogen for downstream power generation. A flash drum separates the H₂-rich gas from the liquid; a distillation column then recovers the unreacted MCH overhead and recycles it to the reactor feed, closing a real tight liquid recycle loop, while spent toluene leaves the bottoms (to be re-hydrogenated back to MCH off-site, closing the supply-chain loop — out of scope for this dehydrogenation-side flowsheet). Screening-fidelity note: MCH and toluene are genuinely close-boiling (relative volatility ~1.4 under this thermo package at column conditions), so the recycle carries real toluene along with the recovered MCH rather than a sharp cut — a production column would use more stages to purify it further; this shows the recycle topology and its convergence, not an optimized column design.
Hydrocracking reaction section
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Benzene hydrogenation → cyclohexane
Benzene + 3 H₂ → cyclohexane in a conversion reactor, then a high-pressure flash recovers liquid cyclohexane and recycles the excess hydrogen (with a purge). The classic ChemSep recycle example — exercises reaction + recycle convergence.
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).
Methyl ethyl ketone from 2-butanol dehydrogenation
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