Coal and Petroleum – Types and Conservation

Fossil Fuels – Coal and Petroleum

Fossil Fuels are natural fuels. They are found deep in the belly of the earth. They are called “Fossil Fuels” because they are formed by the slow decomposition of organic materials such as the remains of dead plants and animals. According to certain estimates, the natural process of converting the dead organic matter to fossil fuel takes hundreds of millions of years. That is why fossil fuels are considered a “non-renewable” energy source.

Today, we will learn about the difference between coal and petroleum, two of the most essential products of fossil fuels.


Fossil fuels come in various types and forms that we may use in our daily life. Some of these include:

  • COAL


There are more similarities between Coal and Petroleum. Both are organic compounds and are majorly formed of hydrocarbons (compounds formed with carbon and hydrogen).

Multiple methods are used to study the physical and chemical properties of these elements. Some of them are density measurement, X-ray diffraction, scanning and transmission, electron microscopy, thermal analysis, and electrical, optical and magnetic measurements.


  • Chemical formula: The chemical formula of coal is C135H96O9NS
  • Density: Coal is slightly denser than water at approximately between 1.1 and 1.5 megagrams per cubic meter.
  • Porosity: Coals are found in a solid state. However, coal is highly porous. The presence of the pores makes coal dangerous since Methane could get trapped in these pores and explode during mining. It is also difficult to measure the distribution and sizes of these pores. The pores are classified into three categories:
    1. Macropores (diameter greater than 50 nanometers);
    2. Mesopores (diameter between 2 and 50 nanometers);
    3. Micropores (less than 2 nanometers). 
  • Reflectivity: Its reflectivity is measured on its polished surface. The reflectivity of coal ranges from a few tenths of a percentage to 12 percent.
  • Hardness and Grindability: Coal is hard and could be ground.


  • Chemical formula: Chemical formula of petroleum and its other derivatives are CnH2n+2
  • Crude oil: Petroleum is known as crude oil.
  • Density: Crude oil has a density of 58 pounds per cubic foot. It floats in seawater because of its density of 64 pounds per cubic foot.
  • Solution gas-oil ratio: It’s a measure of dissolved gas in the oil. GOR of petroleum range between 0 and 2000 scf / bbl (standard cubic feet of nitrogen per barrel of volume.
  • Elemental composition: The elemental composition of petroleum is 82-87% carbon and 11-15% hydrogen. The rest are oxygen, nitrogen and sulfur. While sulfur could range up to 6%, oxygen and nitrogen do not exceed 1.5%.
  • Classes: Petroleum is divided into four classes of compounds – Alkanes (Paraffins), Cycloalkanes (Naphthenes), Aromatic and Heteroaromatic (NSOs).


Various products are obtained from crude oil –

  • Fuel oil – 7%
  • Naphtha – 8%
  • Kerosene – 9%
  • Liquified Petroleum Gas (LPG) – 15%
  • Petrol or Gasoline – 27%
  • Diesel fuel – 32%
  • Other products – 10%


  • Fuel: Coal is used as fuel. Burning coal produces heat. Coal generated heat is used at homes, industries, transportation, etc.
  • Power generation: Coal is widely used to generate electricity across the globe. Coal releases more carbon dioxide into the atmosphere than any other fossil fuel.
  • Metal production: Coke, or metallurgical coal, is used as a key ingredient to producing steel.
  • Cement production: Coal is used as the energy source to produce cement.
  • Gasification and liquefication: It is the most versatile and cleanest way to produce electricity, hydrogen and other valuable energy products.
  • Chemical production: Coal is used in producing various chemicals, such as carbon monoxide (CO), acetic acid and its derivatives, formaldehyde, olefins, etc.
  • Other industrial and nonindustrial uses   


  • Plastic: All plastic products are made using petroleum. Although there is a huge hue and cry about plastic and its damaging effects on the environment, plastic has replaced wood and several other metals and materials and slowed down deforestation, mining, etc.
  • Clothing: Petroleum is used to produce rayon, nylon, polyester, furs, artificial leather, etc.
  • Furniture: Artificial foam, strong but lightweight furniture
  • Kitchenware: Containers, freezers, interior panes, etc.
  •  Automotive: Besides using petrol as fuel, modern automobiles have several parts made from petroleum products.
  • Personal care and cosmetics: Many different oils can be derived from petroleum. Oils, such as propylene and glycol, are used in making soap, lotions, toothpaste, shaving creams, shampoo, deodorant, etc.
  • Packaging: Petroleum products are widely used in packaging as containers or as packing material.
  • Lighting: Wax and other petroleum byproducts are used as lighting fuels.
  • Road construction: Tar, bitumen, etc., are used to construct roads.


Life without the fossil fuels, such as coal and petroleum, is almost impossible in modern times. We take them and their uses for granted. Unfortunately, their sources are depleting, and their uses damage the environment. Care must be taken to use them prudently. Many of them could be recycled, whereas some of them are not. So, considering the wide application of coal and petroleum, it is crucial to use them wisely to maximise their usage and pres