Industrial Chemistry
Chemistry · औद्योगिक रसायन
📋Quick Overview
Industrial chemistry covers the large-scale manufacture of important chemicals. The most exam-relevant processes are: Haber process (ammonia), Contact process (sulphuric acid), Solvay process (sodium carbonate), and petroleum refining. Questions on these processes, their raw materials, catalysts, and products are very common.
📖Important Industrial Processes
| Process | Product | Reaction / Raw Material | Catalyst | Conditions |
|---|---|---|---|---|
| Haber Process | Ammonia (NH₃) | N₂ + 3H₂ → 2NH₃ | Iron (Fe) with Mo promoter | 450°C, 200 atm pressure |
| Contact Process | Sulphuric Acid (H₂SO₄) | 2SO₂ + O₂ → 2SO₃ (then SO₃ + H₂O → H₂SO₄) | Vanadium pentoxide (V₂O₅) | 450°C, 1-2 atm |
| Solvay Process | Sodium Carbonate (Na₂CO₃) | NaCl + NH₃ + CO₂ + H₂O → NaHCO₃ → Na₂CO₃ | NH₃ (recovered and reused) | Low temperature |
| Ostwald Process | Nitric Acid (HNO₃) | 4NH₃ + 5O₂ → 4NO + 6H₂O (then NO→NO₂→HNO₃) | Platinum-Rhodium (Pt-Rh) | 800°C |
| Chlor-Alkali | NaOH + Cl₂ + H₂ | Electrolysis of brine (NaCl solution) | None (electrolysis) | Electric current |
📖Petroleum Refining & Fractional Distillation
Petroleum (crude oil) is a mixture of hydrocarbons. It is refined by fractional distillation — separating fractions based on boiling points. The fractions from lowest BP (top of column) to highest BP (bottom) are:
| Fraction | Boiling Range | Carbon Atoms | Uses |
|---|---|---|---|
| LPG (Petroleum Gas) | < 40°C | C₁-C₄ | Cooking fuel |
| Petrol (Gasoline) | 40-120°C | C₅-C₁₂ | Car/bike fuel |
| Kerosene | 120-180°C | C₁₂-C₁₆ | Jet fuel, lamps, stoves |
| Diesel | 180-250°C | C₁₆-C₂₀ | Truck/bus fuel |
| Lubricating Oil | 250-350°C | C₂₀-C₃₅ | Machine lubrication |
| Paraffin Wax | 350-400°C | C₃₅-C₄₀ | Candles, polish |
| Bitumen/Tar | > 400°C | C₄₀+ | Road surfacing |
📖Other Industrial Products
| Product | Raw Material | Key Process/Fact |
|---|---|---|
| Cement | Limestone (Cite) + Clay | Heated in rotary kiln at ~1500°C. Portland cement most common. |
| Glass | Sand (SiO₂) + Na₂CO₃ + CaCO₃ | Heated to ~1500°C. Soda-lime glass is most common. |
| Paper | Wood pulp (cellulose) | Chemical treatment + bleaching + rolling into sheets |
- •Pyrex glass = borosilicate glass (heat resistant, for lab equipment)
- •Optical glass = lead glass / flint glass (for lenses, prisms)
- •Quartz glass = pure SiO₂ (UV transparent, very expensive)