CARBOB gasoline refers to California Reformulated Gasoline Blendstock for Oxygenate Blending, a specialized petroleum-based component used in producing reformulated gasoline for the state of California. It's designed to meet California's strict environmental standards under the California Air Resources Board (CARB) regulations, which aim to reduce air pollution from vehicle emissions.
Key Characteristics:
- Composition: CARBOB is a blendstock (not finished gasoline) that's typically mixed with 10% ethanol at fuel terminals to create E10 reformulated gasoline. It must comply with low limits on sulfur (≤10 ppm), benzene (≤0.8 vol%), and other aromatics, while containing 3.3–3.7 wt% oxygen after blending.
- Differences from Other Gasolines: Unlike the national standard RBOB (Reformulated Blendstock for Oxygenate Blending) or conventional gasoline, CARBOB has unique formulations tailored for California's climate and emission rules, making it more expensive to produce and often leading to higher pump prices in the state.
- Production and Supply: Only a few U.S. refineries (mostly in California) produce CARBOB, and supply can be tight due to refinery closures or shifts to renewables, contributing to price volatility.
CARBOB ensures finished gasoline meets Phase 3 reformulated standards, promoting cleaner burning fuel in one of the world's largest gasoline markets.