This article explains how dividing wall column (DWC) technology can significantly enhance the performance of light-naphtha isomerization units used to produce high-octane gasoline. Isomerization increases gasoline octane by converting straight-chain paraffins into branched isomers, but reaction equilibrium limits conversion efficiency. Conventional configurations use deisohexanizers, deisopentanizers, and depentanizers to recycle low-octane components and improve Research Octane Number (RON). The authors demonstrate that revamping an existing deisohexanizer (DIH) into a DWC enables sharper separations, additional product cuts, and more effective recycling — without installing new columns.
Up to 93Isomerate RON achieved
+5-20%Throughput boost
1DIH revamped, no new columns
PTQReprinted, Q2 2021
What the article covers
Highlights
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Revamping the deisohexanizer into a DWC enables sharper separations and additional product cuts
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Isomerate RON raised from 87–88 to 89–90, or from 89–90 to 91–93, with 5–20% more throughput
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Reduced capital investment and lower energy consumption, with existing units debottlenecked
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Higher-value gasoline production and improved product quality
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The takeaway
Revamping the DIH into a DWC lifts isomerate RON (up to 91–93) and throughput by 5–20% while reducing capital and energy use — debottlenecking units and improving product quality for higher-value gasoline.
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Challenges with carbon disulfide removal in petrochemical naphtha→Dividing wall distillation columns : PTQ→Optimize Naphtha Processing using Dividing Wall Technology : CEP→Maximize margins in a light naphtha isomerization unit by producing C6 products : Hydrocarbon Processing→Introduction to Dividing Wall Columns : CEP→
