Minerals used in Organic chemicals and Synthetics

 

Until little more than fifty years ago, all but a minute proportion of the oil, gas and coal extracted from the Earth was used as a fuel.  Today, a substantial fraction of world pro­duction (mostly of hydrocarbons) goes to provide feedstock for the production of or­ganic synthetics (see list below). The petro­chemical industry produces relatively cheap alternatives to many natural organic and inorganic materials.  The technology involved in the manufacture of these substances is complex and only the principal processes employed are mentioned here.  The lower unsaturated olefins such as ethylene, C2H4, provide the starting points from which many synthetic molecules are made.  These olefins are obtained largely from the paraffins in crude oil by high-temperature cracking procedures which rupture long car­bon chains and remove excess hydrogen; they can be subsequently combined with mole­cules containing oxygen or chlorine in addi­tion to carbon and hydrogen.  Once formed, these varied compounds provide building blocks for the synthesis of high polymers in which thousands or tens of thousands of atoms are linked.  Polymerisation gives ana­logues of molecules in wood, silk, cotton, rubber and other natural substances for which the synthetic materials can substitute.  A selective list of products is given in the table below:

 

Derivatives of hydrocarbons and coal (other than fuels).

Refinery products

Extracted from crude oils and their derivatives:

  • lubricating oils

  • bitumens

  • waxes (used mainly for waterproofing)

  • detergents (refinery products mixed with other chemicals)

Breakdown products

  •  ammonia and ammonium salts made from hydrogen in combination with atmospheric nitrogen, starting point for synthesis of nitrogenous fertilisers

  • carbon made by high-temperature dissociation, used to strengthen synthetic rubberand forcarbon fibre

 Polymers of hydrocarbon derivatives

  • plastics, e.g. polyethylene, PVC, polystyrene

  • silicones

  • synthetic fibres, e.g. nylon, terylene, acrylic fibre

  • dyes and paints

  • pharmaceuticals

  • insecticides

  • aerosol propellants

  • explosives

Note:  For occurrence and distributin of petroleum and coal in India please refer to 1) India’s Mineral Resources by Krishnaswami and 2) Ore Deposits of India by Gokhale and Rao.

Notes & Handouts

The Himalayas

Kumaon Himalayas

Askot Basemetals

University

   


This website is hosted by

S. Farooq

Department of Geology

Aligarh Muslim University, Aligarh - 202 002 (India)

Phone: 91-571-2721150

email: farooq.amu@gmail.com