Product

C₅ raffinate streams are hydrocarbon mixtures primarily composed of five-carbon (C₅) compounds that remain after valuable C₅ components, such as isoprene and other unsaturated compounds, are removed from a C₅ hydrocarbon stream produced during petroleum refining or steam cracking processes. The term "raffinate" refers to the residual liquid left after extraction or separation of specific target compounds.

Key Characteristics

• Origin: C₅ raffinate is typically generated as a byproduct during the separation and purification steps of petrochemical processes, notably after extracting isoprene, dicyclopentadiene (DCPD), piperylene, and other high-value C₅ olefins from pyrolysis gasoline (“pygas”), a product of the steam cracking of naphtha or other hydrocarbons.

• Composition: The main components often include pentanes (n-pentane, isopentane), residual C₅ olefins (such as isoamylenes), and sometimes cyclopentane, depending on the separation process and feedstock.

• Physical State: C₅ raffinate is a liquid hydrocarbon fraction, typically colorless and highly flammable.

Uses and Value

• Fuel component: Can be blended into gasoline due to its volatility and octane properties.
• Chemical feedstock: Occasional source for further separation or chemical conversions (e.g., isomerization, alkylation).
• Hydrocarbon resin production: May supply certain feedstocks for adhesive and resin manufacturing.

C₅ raffinate streams maximize petrochemical value by allowing the extraction of high-value C5 derivatives and providing a versatile hydrocarbon fraction for further use in fuels or downstream chemical processes.