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INDUSTRIAL CHEMICALS, collage17-819x1024 (1) - Coggle Diagram

- - - - Ideal agent in many chemical process
      - Properties
        
        Acidic
        
        Diprotic Acid
        
        First hydrolysis (100%) complete, but 10% ionise
        
        In the presence of NaOH, conversion of HSO4- ions and SO4^2- is virtually complete
        
        Oxidising
        
        Very strong affinity for water
        
        Concentrated H2SO4 used as a drying agent for air and gases such as O2, CO2 and N2
        
        Cannot be used to dry alkaline bases such as NH3 or reducing agent such as H2S
        
        Dehydrating
        
        Used to remove hydrtogen and oxygen atoms from compounds that do not contain water in a molecular form
        
        Example
        
        Sugar
        
        Wood
        
        Paper
    - - Sources of Sulfur & Sulfur Oxide
        
        Mines
        
        Recovered from petroleum desulfurization
        
        Recovery Sulfur Oxide from Coal
        
        Recovery Sulfur Oxide from smelting of metal sulfide ores
        
        Isolation of SO2 from pyrite
        
        Regeneration of spent acids
  - - - Ammonium Sulfate
      - Superphosphate
    - - Example
        
        Plastics
        
        Synthetic fibers
  - - - Oxidation of Sulphur to SO2 (If Raw Sulphur is Used)
        
        Dry air is used in the combustion process
        
        Molten Sulphur is sprayed into the furnace (burner) to produce Sulfur Dioxide Gas
        
        If sulphur has carbonaceous impurities, must be filtered
        
        Sulphur dioxide produced is then purified and remove moisture and dust or any substances
        
        S(I) + O2 (g) :arrow_right: SO2 (g)
      - Oxidation of Sulphur to SO2 to SO3
        
        SO2 (g) is oxidised to SO3 by O2 using V2O5 (catalyst)
        
        Rate Enhances
        
        Maximising the surface area of catalyst
        
        Increase Temperature
        
        Adding an excess of air
        
        Yields maximises
        
        Using lower temperature (450'C)
        
        Adding an excess of the air to drive the reaction foward
        
        2SO2 (g) + O2 (g) :arrow_right: 2SO3 (g)
      - Absorption of SO3 by impure H2SO4 to produce oleum (H2S2O7)
        
        SO3 is passed into the base of the absorption tower and concentrated H2So4 is applied at the top of the tower
        
        SO3 and H2SO4 meet froming oleum (disulphuric acid)
        
        H2SO4 (l) + SO3 (g) :arrow_right: H2S2O7 (l)
      - Dilution of Oleum to Produce H2SO4
        
        H2S2O7 (l) + H2O (l) :arrow_right: 2H2SO4 (l)
- - - - Ammonium nitrate
      - Calcium ammonium nitrate
    - - Manufacture of hexanedioic acid (adipic acid) to make polyamides.
      - Manufacture of methylbenzene diisocyanate and dinitrobenzene to make polyurethanes.
  - - - Oxidation of ammonia is carried out in a catalyst chamber in which one part of ammonia and eight parts of oxygen by volume are introduced.
      - The temperature of chamber is about 600 °C and contains a platinum gauze which serves as catalyst.
      - Air reheated and mixed with ammonia and passed through a converter.
        
        4NH3(g) + 5O2 → 4NO (g) + 6H2O (g) ΔH = -907 kj/mol
      - Nitrous oxide, nitrogen and water are also simultaneously formed in this step. conditions are carefully controlled in the converter in order to ensure that NO is the main product.
        
        4NH3 (g) + 3O2 → 2N2 (g) + H2O (g)
        
        2NH3 + 2O2 → N2O (g) + 3H2O (g)
      - The catalyst used is 90% platinum alloyed with 10% rhodium (for increase strength) gauzes.
      - The gauze mats are preheated so that the gases are directly heated as they pass over the catalyst.
      - The catalyst may become poisoned by air pollution and contamination from the ammonia which reduces its efficiency.
      - The cost of these catalyst are extremely high and need to be frequently replaced due to the wear and tear they experience under such severe conditions.
    - - Nitrogen monxide is oxidised to nitrogen dioxide as the combustion gases are cooled.
        2NO (g) + O2 (g) → 2NO2 (g) ΔH = -114 kj/mol
      - The oxygen consumed in this step may be added from an external source or is provided by excess oxygen in the gaseous mixture exiting the converter.
      - The temperature of the nitrogen monoxide mixture is reduces to around 200-250 °C in this process.
      - The gases are then passed through a cooling chamber and their temperature reduces to approximately 50 °C.
      - Any condensed water is transferred to the absorption tower.
    - - Water is mixed with the nitrogen dioxide gas in absorption towers to form dilute solutions of nitric acid according to the following overall reaction:
        3NO2 (g) + H2O (l) → 2HNO3 (aq) + NO (g)
      - The towers contain large number of inert plates packed with inert granular materials designed to increase the contact between the gases and water.
      - This reaction is exothermic and continuous cooling is needed.
      - The conversion is favoured by low temperatures and significant reaction occurs until the gases leave the towers.
  - - - Using natural gas, naphtha or hydrogen, over a catalyst, to reduced NO, NO2, N2O gases to N2.
- - - - Haber Process
  - - - Ammonium Nitrate
      - Ammonium SUlphate
      - Urea, (NH2)2CO