How toluene is made
It is named after Tolu, a Colombian tree balsam. Today most of it comes from refineries chasing octane.
- stations
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- things upstream
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- raw sources
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- steps from the ground
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The short version
Refineries make this sweet-smelling liquid as a by-product of chasing octane. Catalytic reformers rearrange naphtha into ring-shaped aromatics, and solvent extraction and distillation then split out benzene, toluene and xylenes. Coal tar gives a smaller stream. Much of the output ends up as benzene and xylenes, as paint and adhesive solvent, or back in gasoline.
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Reform the naphtha
Heated naphtha passes over a platinum catalyst. Straight-chain hydrocarbons are rearranged and partly stripped of hydrogen, leaving a high-octane liquid called reformate that is rich in aromatics.
Goes in -
Or strip coal tar
Coke ovens give a second, smaller source. Light oil from coal tar is 15 to 20 percent of this hydrocarbon, and it is collected for commercial use alongside the refinery supply.
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Pull out the aromatics
A solvent extraction step lifts the ring compounds out of the reformate, leaving the rest to go on to the gasoline pool. The extract is known as BTX, for benzene, toluene and xylenes.
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Distill the three apart
Distillation columns split the BTX stream by boiling point. This one boils at 110.6 °C, between its two siblings, and comes off the column as a colorless liquid.
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Send it three ways
Part goes on to be converted into benzene and xylenes, part into solvents for thinners, paints, lacquers and adhesives, and part into gasoline as an octane booster. It is flammable and toxic, so it moves in sealed tankers.
Worth repeating
- Formula One engines have used toluene as an octane booster.
- Toluene has largely replaced benzene as an aromatic solvent because it is much less toxic.
- It was first named after being isolated in 1841 from balsam of Tolu, a tropical tree extract.
Back to the ground
Follow every input upstream and toluene starts as these 4 raw sources.
Where it goes next
Toluene feeds 1 line directly and reaches 284 things in total.
Further down the line
Keep walking
Sources
Cite this page: "How toluene is made." Assembly Line, 2026-11-03. https://assemblyline.org/make/toluene