Is "Butene/isobutane alkylation" the same as a alkylation unit?

Yes — this model covers what is also called alkylation unit, refinery alkylation, isobutane alkylation. 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 1_butene, isobutane, 2_2_4_trimethylpentane — already selected. You can switch the method on the canvas before running.

Which unit operations are in the flowsheet?

It chains MIX, RXN, DIB. 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. Butene/isobutane alkylation runs entirely in your browser on MaximaLabs — free, no install, no license. Open the model to load it live and run the deterministic solver.

All guides

Reference model (Luyben 2009/2011)

How to simulate butene/isobutane alkylation

Sulfuric-acid alkylation of butene with excess isobutane produces high-octane alkylate gasoline blendstock; a conversion reactor stands in for the acid-catalyzed carbocation chemistry (a literal acid/hydrocarbon settler would need H₂SO₄ electrolyte thermodynamics this package doesn't carry — out of scope, same as the reactor already being a stand-in for the chemistry itself), and a deisobutanizer-style column recovers unreacted isobutane overhead. The high isobutane:olefin ratio real alkylation units run is maintained almost entirely by **recycling** that isobutane back to the reactor feed — closed here as a real Wegstein-converged tear loop, with only a small makeup feed replacing what the reaction actually consumes, rather than the previous version's isobutane leaving as an unrecycled product. Luyben, Principles and Case Studies of Simultaneous Design, Wiley (2011); Ind. Eng. Chem. Res. 2009, 48, 11081.

Also known as: alkylation unit, refinery alkylation, isobutane alkylation.

Butene

Isobutane Makeup

MIX

RXN

feed

dist

btms

DIB

Alkylate

1
Open the ready-made model
Open the "Butene/isobutane alkylation" model in the MaximaLabs workspace — no install, no license. It loads live on the canvas, ready to edit and run.
2
Confirm the thermodynamics
This process is modeled with the PENG-ROBINSON property package over 1_butene, isobutane, 2_2_4_trimethylpentane — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
3
Review the flowsheet
The flowsheet chains MIX, RXN, DIB. Every block is a real, solvable unit op you can reconfigure on the canvas.
4
Run 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.
5
Read 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.

What you'll build

Thermodynamics: PENG-ROBINSON
Components: 1_butene, isobutane, 2_2_4_trimethylpentane
Unit operations: MIXRXNDIB

Open this model in the workspace

Opens live on the canvas — free, no install.

Explore the model & flowsheet

Frequently asked questions

What does the Butene/isobutane alkylation model simulate?: Sulfuric-acid alkylation of butene with excess isobutane produces high-octane alkylate gasoline blendstock; a conversion reactor stands in for the acid-catalyzed carbocation chemistry (a literal acid/hydrocarbon settler would need H₂SO₄ electrolyte thermodynamics this package doesn't carry — out of scope, same as the reactor already being a stand-in for the chemistry itself), and a deisobutanizer-style column recovers unreacted isobutane overhead. The high isobutane:olefin ratio real alkylation units run is maintained almost entirely by **recycling** that isobutane back to the reactor feed — closed here as a real Wegstein-converged tear loop, with only a small makeup feed replacing what the reaction actually consumes, rather than the previous version's isobutane leaving as an unrecycled product. Luyben, Principles and Case Studies of Simultaneous Design, Wiley (2011); Ind. Eng. Chem. Res. 2009, 48, 11081.
Is "Butene/isobutane alkylation" the same as a alkylation unit?: Yes — this model covers what is also called alkylation unit, refinery alkylation, isobutane alkylation. 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 1_butene, isobutane, 2_2_4_trimethylpentane — already selected. You can switch the method on the canvas before running.
Which unit operations are in the flowsheet?: It chains MIX, RXN, DIB. 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. Butene/isobutane alkylation 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

Reference model (Luyben 2010)

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Reference model

Recycle loop

A mixer/heater/splitter loop with a tear stream — exercises Wegstein recycle convergence.

Reference model (ChemSep)

Propane refrigeration cycle

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