Unit 1: Industrial Gases and Inorganic Chemicals
Course Code: CHM-DSC-353
Paper Name: Industrial Chemistry
1. Industrial Gases
Industrial gases are gaseous materials manufactured for use in industry. The most common are produced through the Fractional Distillation of Liquefied Air.
Production and Uses
- Oxygen (O2): Produced by air liquefaction. Used in steel manufacturing (BOF process), oxy-acetylene welding, and medical life support.
- Nitrogen (N2): Produced via fractional distillation. Used to provide an inert atmosphere, in food packaging, and for the synthesis of Ammonia (Haber Process).
- Hydrogen (H2): Produced by Steam Reforming of Methane or electrolysis of water. Used in hydrogenation of oils, rocket fuel, and fuel cells.
- Carbon Dioxide (CO2): Obtained as a byproduct in ammonia synthesis or from flue gases. Used in carbonated drinks, as a refrigerant (dry ice), and in fire extinguishers.
2. Rare Gases
Noble gases like Argon, Neon, and Helium are extracted from air (except Helium, which is often extracted from natural gas).
- Argon: Used in incandescent light bulbs and as a shielding gas in TIG welding.
- Helium: Used in cryogenics (cooling MRI magnets) and weather balloons.
- Neon: Primarily used in advertising signs (Neon lights).
3. Inorganic Chemicals: Boron Compounds
The unit covers the industrial preparation of essential boron derivatives.
- Boric Acid (H3BO3): Prepared by reacting borax with a mineral acid like HCl or H2SO4. Used as an antiseptic and in glass manufacturing.
- Borax (Na2B4O7·10H2O): Found naturally as Tincal. Used as a flux in soldering and in the production of heat-resistant glass (Pyrex).
4. Nitrogen Compounds and Fertilizers
The industrial production of nitrogen-based chemicals is vital for agriculture.
- Ammonium Sulphate: Produced by the reaction of Ammonia with Sulphuric acid or using the Merseberg Process (Gypsum + Ammonia + CO2).
- Calcium Ammonium Nitrate (CAN): A widely used neutral fertilizer produced by mixing Ammonium Nitrate with limestone.
5. Bleaching Powder and Special Chemicals
Inorganic chemicals used for sanitation and industrial bleaching.
Bleaching Powder (CaOCl2)
Produced by the action of chlorine gas on dry slaked lime [Ca(OH)2].
Reaction: Ca(OH)2 + Cl2 → CaOCl2 + H2O
- Uses: Bleaching cotton/linen, disinfecting drinking water, and as an oxidizing agent in laboratories.
Potassium Permanganate (KMnO4)
Manufactured from the mineral Pyrolusite (MnO2). It is a powerful oxidizing agent used in water treatment and qualitative analysis.
6. Exam Focus: Tips and FAQs
Exam Tips
- Steam Reforming: Be ready to write the chemical equation for Hydrogen production: CH4 + H2O → CO + 3H2.
- Inert Atmosphere: Explain why Nitrogen or Argon is chosen for specific industrial processes (lack of reactivity).
- Haber Process: Though covered in earlier semesters, its integration with Nitrogen production is a common question.
Frequently Asked Questions
Q: What is "Dry Ice"?
A: It is solid Carbon Dioxide, which undergoes sublimation (turns directly from solid to gas) at -78.5°C.
Q: Why is CAN preferred over pure Ammonium Nitrate as a fertilizer?
A: Pure Ammonium Nitrate is explosive and acidic; adding limestone (calcium carbonate) makes it safer to handle and chemically neutral.
Q: How is Argon obtained industrially?
A: As a byproduct during the fractional distillation of liquid air, as its boiling point lies between that of Nitrogen and Oxygen.