Bitumen manufacture feed type: Highest-quality paving/industrial bitumen is generally produced from which crude oil family?

Introduction:
Bitumen (asphalt) quality depends on the composition of the vacuum residue obtained from crude oil. Crude family (paraffinic vs naphthenic/aromatic) strongly affects asphaltene/resin balance and, hence, final bitumen properties such as penetration, softening point, and durability.

Given Data / Assumptions:

• Feed to bitumen production is typically vacuum residue.
• Naphthenic (asphaltic-base) crudes yield residues richer in asphaltenes/resins appropriate for bitumen.

Concept / Approach:
Naphthenic/asphaltic-base crudes provide a residue with the colloidal structure desired in bitumen, facilitating target penetration grades and temperature susceptibility. Paraffinic-base residues may require more processing or may be less suitable for high-quality paving grades without blending/modification.

Step-by-Step Solution:

Verification / Alternative check:
Refinery practice often prefers asphaltic-base (naphthenic) crudes for making premium paving bitumen.

Why Other Options Are Wrong:

• Paraffinic/Mixed/Intermediate: May produce less suitable residues or require blending.
• Super-light condensate: Too light; negligible residue for bitumen.

Common Pitfalls:
Assuming any heavy residue makes good bitumen—colloidal balance matters.

Final Answer:
Naphthenic