The document describes the manufacturing process for TNT (tri-nitro-toluene) through a three stage nitration process. The process involves: 1) Nitrating toluene with nitrogen pentoxide in the presence of dichloromethane to produce mono-nitro-toluene. 2) Treating the mono-nitro-toluene with nitric acid to produce di-nitro-toluene. 3) Reacting the di-nitro-toluene with nitrogen pentoxide dissolved in sulfuric acid to produce TNT. The process aims to control temperatures, residence times, and yields at each stage to minimize unwanted meta-isomer byproducts and maximize

1. TNT Production
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2. Manufacturing process of TNT 2

3. Nitration:
Nitration is done in three following steps to
obtain TNT(Tri-Nitro-Toluene).
First stage nitration:
This nitration is done by treating
toluene with N2O5 in the presence of DCM (Di-
chloro-methane).
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4. Process Flow Diagram for First Stage Nitration 4

5. Conditions:
 Temperature should be -30 (mixing temp)
-50oC(Reactor exiting temp).
 Residence time 15 to 20 min.
 At such conditions we obtain 54.2% ortho
44.3% para and 1.5% of meta isomer.
 Meta-isomers can be further reduce (to about
if conditions are more precise i.e -40oC mixing
temperature & -60oC reactor exiting temperature.
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6. Extraction of MNT
Neutralization step:
After 1st stage nitration, the product is neutralized with
aqueous sodium bicarbonate (NaHCO3) and the
layer recovered.
Concentrating Unit:
After the neutralization process any other amount of
remaining acid or water is removed by using wiped
evaporator.
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7. Second Stage Nitration:
It is done by treating MNT (Mono-Nitro-
toluene) with HNO3 (Nitric Acid) .
Yield is up to 90%.
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8. Addition of DCM:
 Act as a heat sink for removal of heat.
 Secondly to slow down the reaction and therefore control
the exotherm.
Conditions:
 6oC to 30oC temperature.
 Reaction time 5 min.
 Residence time up to 10 min.
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9. Extraction of DNT
 Measured amount of DCM and water is added to
induce phase separation.
 The layer is separated and DNT is isolated from
each layer.
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10.  Waste acids are recovered.
 Recovery of DCM by cryogenic condensation.
 After this DNT is introduced in Third stage
reaction chamber.
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11. Third Stage Nitration:
Here DNT is treated with N2O5 dissolved in H2SO4.
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12. Conditions:
 Temperature should be 50oC to 70oC.
 Reaction time 6.5 hr.
Yield obtained is about 85%
Kinetics:
Kinetics of this reaction is relatively slow, that’s why
we have to shift this process to batch process.
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13. Extracting of TNT:
 Addition of DCM will extract most of the TNT
the acid.
 Two layers are formed with around 75% of the
in the organic layer.
 Dilution with water and addition of DCM to the
acid layer recovered the majority of the
TNT.
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14. Neutralization:
 It is neutralized by adding NaHCO3.
 After neutralization DCM is removed giving solid
product of TNT
Washing:
It is washed with cold water.
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15. Drying:
 Drying in a vacuum oven at 50oC
overnight
 TNT as a yellow/white solid (88%).
 A purity of 99%.
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16. Advantages:
 Better Yield.
 Lowest possible formation of meta isomers.
Disadvantages:
 Expensive raw materials (N2O5 AND DCM).
 Time consuming.
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17. Traditional
Method
Advance
Method
Raw Materials are cheap and easily
available
Raw Materials are expensive
Production of NOx & SOx No Harmful gases produced
Yield is about 75-80% Yield is about 88-95%
14-15% Meta isomer production >2% meta isomer production
Red water production during washing No harmful liquid production during
washing
Comparison between traditional and advance method 17

18. Lab Scale TNT production plant
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