Chemical Industries II SS1 Chemistry Lesson Note

DIVISION OF THE CHEMICAL INDUSTRIES

Chemical industries can be classified based on their products. We have chemical industries which produce:

(a) Basic chemicals such as acids, alkalis, salt and organic chemicals.

(b) Chemical products that are used in the manufacture of artificial fibres and plastics.

(c) Chemical products used as starting materials in other industries that manufacture substances such as paints, fertilizers and explosives.

(d) Chemical products such as cosmetics, drugs and soap for personal use.

HEAVY AND FINE CHEMICALS

1. Heavy Chemicals: They are classified as heavy chemicals because they are required in large quantities in different types of chemical industries all over the world. 

Heavy chemicals include tetraoxosulphate (vi) acid (the most important) hydrochloric acid, trinitrate (v) acid calcium trioxocarbonate (iv) acid, caustic soda (sodium hydroxide), Slaked lime, Ca(OH)2  and their special derivative, such as Caustic potash, Sodium trioxocarbonate(iv) acid, bleaching powder (CaOCl2).

Metals such as iron, copper, tin, aluminium and zinc are also heavy chemicals, as well as organic materials such as coke, coal tar, benzene, and methyl benzene. NH3 is also a heavy chemical. It is manufactured in large quantities and is used to make fertilizers as well as explosives.

2. FINE CHEMICALS: They are manufactured only in small quantities for paints and fuels, drugs, analytical chemicals, bulk laboratory reagents acids photographic materials. Their purity is generally of a higher degree than that of heavy chemicals, and so they are correspondingly more expensive.

TYPES OF INDUSTRY

Due to different types of naturally occurring raw materials, many chemical industries have been established some of these industries are:

1. Fertilizer Industry
2. Paint Industry
3. Cement Industry
4. Plastic Industry
5. Pharmaceutical Industry

1. FERTILIZER INDUSTRY: The fertilizer industry is important. Fertilizers such as NH4NO3, (NH4)2SO4 and Urea, as well as pesticides, insecticides, germicides, herbicides and fungicides, are all products of the petrochemical industry which help in agricultural production.
2. PAINT INDUSTRY: Paint is a fluid mixture which contains suspended colouring materials. The main use of paints is for decoration and protection against weathering and corrosion.
3. CEMENT INDUSTRY: Cement is produced by heating a mixture of powdered lime (CaO) and clay. When mixed with water, it can be used to fasten stones and bricks together. The mixture called mortar hardens like stone.
4. PLASTIC INDUSTRY: The plastic industry is divided into four categories; bags, household, industrial plastics splasticmiscellaneous items.

The industrial plastics supplies cover items such as casing for radios, Cassette recorders and TV sets, as well as PVC pipes and fittings for the building industry. The starting raw materials for the modern plastic industry are obtained by fractional distillation of crude oil petroleum. The major raw material in the plastic industry is ethene.

5. PHARMACEUTICAL INDUSTRY: Many plant extracts are known to have some medical properties. Most medicinal are organic compounds, but many inorganic substances are still used in pharmacy, for example; Potassium bromine, used as a sedative, bismuth carbonate, used to cure stomach disorders, mercury nitrate, used as an antiseptic for skin diseases; and mercury (1) chloride, used as a strong purgative. 

Drugs can be used to cure disease. Drugs such as quinine for the treatment of malaria and insulin for the treatment of diabetes are examples. Many of our synthetic drugs, syringes, and surgical and important materials in hospitals are manufactured from petrochemical products. 

Disinfectants, Cosmetics, detergents and soap are also products of petrochemicals

ASSIGNMENT 

1. (a) Give one example of (i) Heavy chemicals, (ii) Fine chemicals 

(b) Name the major raw materials used in the manufacture of the following: (i) Polythene, (ii) Cement (iii) Soap

2. (a) What is a chemical industry?

(b) Mention three types of chemical industries