Fractional Distillation of Crude Petroleum
24 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary purpose of fractional distillation of crude petroleum?

  • To produce high molecular weight hydrocarbons
  • To remove impurities from crude petroleum
  • To create a mixture of gasoline and diesel
  • To separate various fractions of hydrocarbons (correct)

    • What is the term for the process of breaking high molecular weight hydrocarbons into low molecular weight compounds?

  • Knocking
  • Fractional distillation
  • Octane rating
  • Cracking (correct)

    • What is the primary cause of knocking in an internal combustion engine?

  • Low octane rating of the fuel
  • Excessive heat in the engine cylinder
  • Premature combustion of the air-fuel mixture (correct)
  • Insufficient compression of the air-fuel mixture

    • What is the purpose of adding Tetraethyl Lead (TEL) to gasoline?

    <p>To increase the octane rating of the fuel</p> Signup and view all the answers

    What is the inverse function of a fuel's ignition delay?

    <p>Cetane number</p> Signup and view all the answers

    What is the primary property of diesel fuel that affects engine performance and emission?

    <p>Cetane number</p> Signup and view all the answers

    What is the purpose of the cetane number in diesel fuel?

    <p>To measure the fuel's ignition delay</p> Signup and view all the answers

    What is the effect of increasing the cetane number of diesel fuel?

    <p>Decrease in ignition temperature</p> Signup and view all the answers

    During what process is LPG obtained as a byproduct?

    <p>All of the above</p> Signup and view all the answers

    What is the main component of CNG?

    <p>Methane</p> Signup and view all the answers

    What is the caloric value of LPG?

    <p>26200 kcal/Nm³</p> Signup and view all the answers

    What is a beneficial property of LPG in regards to鋼alloys?

    <p>It is non-corrosive to steel and copper alloys.</p> Signup and view all the answers

    What is the main use of LPG in domestic and industrial applications?

    <p>As a domestic fuel</p> Signup and view all the answers

    What is CNG mainly composed of?

    <p>Methane and Ethane</p> Signup and view all the answers

    What is a benefit of using CNG over petrol and diesel?

    <p>It produces fewer greenhouse gases</p> Signup and view all the answers

    What is a property of CNG that makes it efficient in engines?

    <p>It has a high calorific value</p> Signup and view all the answers

    What is the purpose of the oxygen cylinder in the combustion reaction?

    <p>To provide oxygen for the fuel combustion</p> Signup and view all the answers

    What is the process of separating crude oil into different fractions based on their boiling points?

    <p>Fractional Distillation</p> Signup and view all the answers

    What is the term for the uncondensed residue left in the iron retort after fractional distillation?

    <p>Asphalt or Pitch</p> Signup and view all the answers

    What is the purpose of the horizontal trays in the fractionating tower?

    <p>To provide a pathway for the vapors to condense</p> Signup and view all the answers

    What is the term for the temperature at which a fuel ignites?

    <p>Flash Point</p> Signup and view all the answers

    What is the process of breaking down large molecules into smaller ones?

    <p>Cracking</p> Signup and view all the answers

    What is the term for the detonation of a fuel inside an engine, resulting in a knocking sound?

    <p>Knocking</p> Signup and view all the answers

    What is the term for the measure of a fuel's resistance to knocking?

    <p>Octane Number</p> Signup and view all the answers

    Study Notes

    Fractions Obtained in Fractional Distillation

    • Crude petroleum undergoes fractional distillation to produce various fractions

    Cracking

    • Process of breaking high molecular weight hydrocarbons into low molecular weight compounds like gasoline, diesel, olefins, etc.
    • Thermal cracking: carried out in the presence of heat
    • Catalytic cracking: carried out in the presence of a catalyst

    Knocking

    • Premature combustion of part of the compressed air-fuel mixture in the IC engine cylinder
    • Causes a sharp sound and sudden pressure rise
    • Prevented by adding anti-knocking agents like Tetraethyl Lead (TEL) in gasoline

    Octane Number

    • Measure of a fuel's ability to resist knocking when ignited with air in an IC engine
    • Higher octane number indicates lower knocking property
    • Can be increased by adding TEL, but increases air pollution by emitting lead particles

    Cetane Number

    • Measure of a diesel fuel's ignition properties
    • Percentage of hexadecane present in a mixture of hexadecane and 2-methyl naphthalene
    • Higher cetane number indicates lower ignition temperature and better fuel performance

    Gaseous Fuels: LPG, CNG, Biogas

    • LPG (Liquefied Petroleum Gas): byproduct of crude oil distillation or heavy oil cracking
    • Composition: Ethane (0.20%), Propane (57.30%), Butane (41.10%), Pentane (1.40%)
    • Properties: highly flammable, colorless, odorless, high calorific value, non-corrosive

    Uses of LPG

    • Domestic fuel (liquid butane) and industrial fuel (liquid propane)
    • Motor fuel, as it mixes with air and burns cleanly
    • Used in aerosol industries

    CNG (Compressed Natural Gas)

    • Made by compressing natural gas to less than 1% of its volume at standard atmospheric pressure
    • Composition: CH4 (methane) = 88.5%, C2H6 (ethane) = 5.5%, C3H8 (propane) = 3.7%, etc.
    • Properties: cheaper than petrol or diesel, ignition temperature = 540°C, odourless, non-toxic, non-corrosive, lightweight, high calorific value

    Calorimeter

    • Measures heat produced by fuel combustion
    • Consists of a bomb, copper calorimeter, thermometer, and stirrer
    • Initial temperature of water in the calorimeter is measured by a thermometer
    • Oxygen is admitted into the bomb, and the fuel is ignited by an electric circuit
    • Heat produced by combustion raises the temperature of the calorimeter water, which is recorded by the thermometer

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    This quiz covers the fractions obtained in the fractional distillation of crude petroleum, including cracking and its types. Learn about the process of breaking high molecular weight hydrocarbons into low molecular weight compounds.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser