Question

In petroleum refining, atmospheric distillation is primarily used to:

• A. Crack heavy hydrocarbons
• B. Separate crude oil into boiling-range fractions
• C. Remove sulfur compounds
• D. Increase octane number

Hint:

Memory Tip: Distillation column separates; cracking unit converts.

Answer 1

The Correct Option is B

Concept:
Atmospheric distillation is the first major separation step in petroleum refining. It separates crude oil into useful fractions based on boiling points.

Step 1:
Crude oil is heated to partially vaporize it before entering the distillation column.

Step 2:
Different hydrocarbons condense at different temperatures inside the column.

Step 3:
Products such as gases, naphtha, kerosene, diesel, and residue are withdrawn at different levels.

Step 4:
Cracking, desulfurization, and octane improvement are separate refinery processes.

Step 5:
Hence, atmospheric distillation is mainly used to separate crude oil into boiling-range fractions.