Is "Hydrocracking reaction section" the same as a hydrocracker unit?

Yes — this model covers what is also called hydrocracker unit, hydrocracking unit, HCU, VGO hydrocracker. 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 n_dodecane, n_octane, n_butane, n_pentane, propane, h2 — already selected. You can switch the method on the canvas before running.

Which unit operations are in the flowsheet?

It chains HC, SEP. 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. Hydrocracking reaction section 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

Hydrocracker complex, Jamnagar, India

How to simulate hydrocracking reaction section

A refinery hydrocracker: heavy VGO (modeled as n-dodecane) plus excess H₂ is cracked over catalyst into lighter products via a discrete lumped first-order kinetic network, then flashed to knock out recycle H₂/light gas from the liquid product (Peng-Robinson). Conversion is set by reactor temperature and LHSV.

Also known as: hydrocracker unit, hydrocracking unit, HCU, VGO hydrocracker.

FEED

SEP

Recycle GAS

Liquid Product

1
Open the ready-made model
Open the "Hydrocracking reaction section" 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 n_dodecane, n_octane, n_butane, n_pentane, propane, h2 — already selected, so the phase equilibrium and enthalpy are physically consistent from the first run.
3
Review the flowsheet
The flowsheet chains HC, SEP. 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: n_dodecane, n_octane, n_butane, n_pentane, propane, h2
Unit operations: HCSEP

Open this model in the workspace

Opens live on the canvas — free, no install.

Explore the model & flowsheet

Frequently asked questions

What does the Hydrocracking reaction section model simulate?: A refinery hydrocracker: heavy VGO (modeled as n-dodecane) plus excess H₂ is cracked over catalyst into lighter products via a discrete lumped first-order kinetic network, then flashed to knock out recycle H₂/light gas from the liquid product (Peng-Robinson). Conversion is set by reactor temperature and LHSV.
Is "Hydrocracking reaction section" the same as a hydrocracker unit?: Yes — this model covers what is also called hydrocracker unit, hydrocracking unit, HCU, VGO hydrocracker. 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 n_dodecane, n_octane, n_butane, n_pentane, propane, h2 — already selected. You can switch the method on the canvas before running.
Which unit operations are in the flowsheet?: It chains HC, SEP. 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. Hydrocracking reaction section 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

Hydrocracker complex, Jamnagar, India

Hydrocracking fractionation train

The standard downstream train a hydrocracker reaction section feeds into: a high-pressure separator knocks the H₂-rich recycle gas off the reactor effluent, a letdown valve drops the liquid to low pressure for a second flash (LPG-range off-gas), then a fractionator (crude_distillation, one side draw) splits what remains into light naphtha, a kerosene/diesel cut, and unconverted oil bottoms. A textbook train topology (Gary & Handwerk-style HP-sep → letdown → LP-sep → fractionator), not a replication of any specific published paper's numbers — the reaction lumps/kinetics are the same illustrative n-paraffin network as the 'hydrocracker-unit' example, not a real assay.

Reference model (ChemSep)

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.

Reference model (Luyben 2010)

Cumene production (benzene alkylation)

Benzene and propylene alkylate over a fixed-conversion reactor to cumene (isopropylbenzene, the feedstock for phenol/acetone via the Hock process); a downstream column recovers unreacted benzene overhead for recycle-quality purity while cumene leaves the bottoms. Luyben, Ind. Eng. Chem. Res. 2010, 49, 719.

Reference model (Luyben 2009/2011)

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.

Reference model (2009 kinetics)

Ethylene oxide hydration to mono-ethylene glycol (MEG)

Ethylene oxide reacts uncatalyzed with excess water at 200 C to mono-ethylene glycol (MEG, antifreeze/PET feedstock); the excess-water dilution that suppresses the over-reaction to di-/tri-ethylene glycol byproducts is reflected in the large water excess on the feed, and a downstream column concentrates MEG in the bottoms while excess water leaves overhead for recycle. Kinetics basis: Ind. Eng. Chem. Res. 2009, 48, 10840.

EO/EG complex, Beaumont, Texas, USA

Ethylene oxide synthesis through to glycol

The full EO/MEG chain in one flowsheet, upstream of the standalone hydration example: ethylene and oxygen react over a silver catalyst to ethylene oxide (low per-pass ethylene conversion, ~10%, is realistic — high conversion pushes the competing total-combustion side reaction, which this model represents as a second reactor consuming a fixed share of the same ethylene at ~80% EO selectivity). A cooled flash condenses EO (and reaction water) from the unreacted ethylene/oxygen/CO₂ vented for combustion-side purge; the condensed EO then hydrates with fresh water to MEG exactly as in the standalone hydration example. No ethylene/O₂ recycle loop (an honest simplification — real plants recycle unreacted ethylene at high ratio).