Refinery Products

Question 1

How does the petroleum industry classify hydrocarbon compounds?

Answer 1

Hydrocarbon compounds are characterized by the number of carbon atoms and unsaturated bonds in the molecule (e.g., Propane ➔ C3, Propylene ➔ C3=).

Question 2

What are the main product classes made by the US petroleum industry?

Answer 2

Examples include fuel gas, liquefied gases, gasolines, jet fuels, kerosines, diesel fuels, lubricating oils, asphalts, and waxes.

Question 3

What are some examples of low-boiling products?

Answer 3

Methane, ethane, propane, and butanes, including their olefinic counterparts, are examples.

Question 4

What are typical uses of methane (C1) in refineries?

Answer 4

Methane is used as a refinery fuel and as a feedstock for hydrogen production via pyrolytic cracking.

Question 5

How is ethane (C2) utilized in refineries?

Answer 5

It is used as a fuel or a feedstock for producing hydrogen and ethylene in petrochemical processes.

Question 6

Why is normal butane preferred for blending into gasoline?

Answer 6

Normal butane has a lower vapor pressure (52 psi) than isobutane (71 psi), making it suitable for regulating vapor pressure in gasoline.

Question 7

What percentage of gasoline in the USA is used as fuel for automobiles?

Answer 7

90% of the gasoline produced in the USA is used as automobile fuel.

Question 8

What is the key difference between regular and premium gasoline?

Answer 8

The principal difference lies in their antiknock performance, measured by octane numbers.

Question 9

Octane Rating means

Answer 9

A measure how well gasoline burns, measured on a scale 0-100. It is increased by using an anti knock agent.

Question 10

What are the important gasoline specifications?

Answer 10

• High antiknock quality
• Ease of starting
• Quick warm up
• Low tendency to vapor lock
• Low engine deposits

Question 11

What is ASTM distillation in the context of gasoline?

Answer 11

It is a standardized laboratory batch distillation method to determine naphthas and middle distillates carried out at atmospheric pressure without fractionation.

Question 12

Different MON and RON

Answer 12

• RON: represents the performance during low-speed driving when acceleration is relatively frequent.
• MON: Guide to engine performance at high speeds or under heavy load conditions.

RON and MON of gasoline is an indicator of the changes in performance under both city and highway driving and is known as the sensitivity of the fuel.

Question 13

Type of distillate fuels

Answer 13

• Jet fuels
• Diesel fuels
• Heating oils

Question 14

What is the critical specification for jet fuel related to its burning quality?

Answer 14

The smoke point, which limits the percentage of cracked products high in aromatics, is critical.
Smoke point: A test measuring burning quality of jet fuels, kerosines and illuminating oils. It is defined as the height of the flame millimeters beyond which smoking takes place.

Question 15

How is freeze point specification achieved for jet fuels?

Answer 15

Freeze point is very low.
Hydrocracking is used to isomerize paraffins, lowering the freeze points.

Question 16

How does No. 2 diesel fuel differ from No. 1 diesel fuel?

Answer 16

No. 2 diesel has a wider boiling range (350–650°F) and is blended with cracked stocks,
No. 1 diesel is made from virgin stocks and has a boiling range of 360–600°F. Used in high-speed engine in truck and buses.

Question 17

What is the cetane number, and why is it important for diesel fuels?

Answer 17

The cetane number measures the ignition quality of diesel, synonymous with the octane number for gasoline, and is a critical specification for engine performance.

Question 18

What are the three most important properties of diesel fuel?

Answer 18

Volatility, ignition quality, and viscosity are the three critical properties.

Question 19

What is catalytic reforming, and why is it performed?

Answer 19

Catalytic reforming upgrades octane levels in gasoline products by processing feedstocks like heavy straight-run (HSR) and coker gasoline.

Question 20

Why is alkylation preferred over polymerization in modern refineries?

Answer 20

Alkylation produces larger quantities of high-octane products from light olefins, making it more efficient and favorable.

Question 21

How does RVP (Reid Vapor Pressure) affect gasoline performance?

Answer 21

RVP governs vapor lock tendencies and evaporation losses, with adjustments made seasonally to maintain balance.