(191c) Apu, a Novel Technology for Producing High Purity Btx

Naphtha cracking produces light olefins for polymer applications, but also produces pyrolysis gasoline (pygas), which is rich in aromatic compounds and a significant source of BTX. Pygas has been a component in the gasoline pool, but is increasingly used for its higher petrochemical value. This requires the separation of BTX components, via extraction, from aliphatic compounds and C9+ aromatics. In many cases, naphtha crackers have been extensively debottlenecked to add capacity; however, existing extraction units do not always have the flexibility to support significant capacity increases. Due to aromatics limitations in the gasoline pool, the high value of ethylene, propylene and BTX intermediates, the idea of converting C7+ pygas to these highly desired components is an attractive option.

The Advanced Pygas Upgrading (APU) process developed by SK and designed by Axens, refines the aromatics-rich hydrogenated pygas by converting non-aromatics into ethane and LPG and C9+ aromatics into BTX. This enables the use of the BTX liquid stream for chemical use without further extraction and recycling the LPG to the light ends cracker furnace.

The presentation will provide a description of the APU Process along with some study cases showing economic benefits.