Petroleum Refinery Engineering MCQ Questions & Answers | Chemical Engineering

In petroleum refinery engineering, gasoline fraction of a crude oil will have the maximum gravity API (°API).

The gravity API (°API) is a measure of the density of petroleum liquids compared to water. Higher API gravity values indicate lighter and less dense liquids. Gasoline is typically one of the lightest fractions obtained from crude oil refining processes, and therefore, it tends to have the highest API gravity among the options provided.

Therefore, the correct option is Option B: Gasoline.

Option A: Diesel - Diesel is a petroleum distillate commonly used as fuel in compression-ignition engines. The aniline point of diesel is typically higher compared to naphtha or gasoline. Diesel contains fewer aromatic hydrocarbons compared to naphtha, which results in a higher aniline point.

Option B: LPG - LPG (liquefied petroleum gas) consists primarily of propane and butane. It is not typically tested for aniline point as it is composed mainly of aliphatic hydrocarbons, which have lower aromatic content compared to naphtha.

Option C: Naphtha - Naphtha is a petroleum fraction containing a mixture of hydrocarbons, including both aliphatic and aromatic compounds. The aniline point of naphtha is determined by the temperature at which it becomes completely miscible with an equal volume of aniline. Naphtha contains a significant amount of aromatic hydrocarbons, which contribute to its aniline point.

Option D: Gasoline - Gasoline, like naphtha, is a petroleum fraction containing a mixture of hydrocarbons. It typically contains a higher proportion of light hydrocarbons and fewer aromatics compared to naphtha. Gasoline tends to have a lower aniline point compared to naphtha due to its lower aromatic content.

Conclusion:
Among the options provided, Option C: Naphtha is the petroleum product commonly associated with the aniline point. Naphtha contains a significant amount of aromatic hydrocarbons, which influence its aniline point. Therefore, the correct answer is Option C: Naphtha.