Rezel-POG olefin enhancement additive provides refiners with the flexibility to operate in a high propylene mode without the activity dilution of the base catalyst inventory.
Rezel POG additives were developed by high crystal ZSM-5 content in the additive without degradation in the physical properties, particularly particle strength and the pore diameter of modified ZSM-5 crystal structure allows only linear compounds to enter. The active acid sites within the crystal reacts with naphtha and LCO-range olefinic compounds, and cracks them into C3, C4 and some C5 olefins. Long-chain naphtha-range olefins generally have low octane values. POG additives selectively crack these low-octane olefins into propylene, butylene and isobutene, thereby concentrating the remaining higher octane molecules and increasing the FCC naphtha octane value. Additionally, POG additives facilitate isomerization reactions in naphtha boiling-range molecules by increasing branched compounds in the naphtha range.
Rezel-POG ZSM-5 Additive was commercially applied in a side-by-side design FCCU with 2 stage regeneration in an east China refinery.