industry of suphuric acid by Rehman ali.

2. Alishay baig ………..16381507-011
Urwa zubair………….16381507-033
Rehman Ali…………...16381507-014

3. Industry Of Suphuric AciD

4.  Molecular formula :
 H2SO4
 Chemical Names :
 Sulphuric acid/oil of vitriol/dihydrogen sulphate/king of chemicals
 Molecular weight :
 98 g/mol
 Boiling point :
 340

5. Sulfuric acid is a colorless oily liquid.
 It is soluble in water with release of heat.
 It is corrosive to metals.

6. There are two method of prepartaion :
1. Contact process
2. Lead chamber process

7.  Contact process consist three stages .
1. Preparation of sulfur dioxide.
2. Conversion of sulphur dioxide into sulfur
trioxide.
3. Conversion of sulfur trioxide formed into
concentrated H2SO4.
 The major raw material are :
1. Sulphur
2. Air
3. Water

8. Step 1: Preparation of sulphur dioxide:
 SO2 is prepared by burning sulphur in the
presence of excess air at 100 c in sulphur burner
so that the product combines with oxygen.
 S(s) + O2 (g) → SO2(g)

9. Cooled the gases through cooler pipes.
Passed through coarse coke filter.
Then passes through cotterell electrostatic
mist precipitator.

10. Step 2: Preparation of sulphur trioxide:
 when sulphur dioxide reacts with oxygen at
a temperature of 400°C – 450°C and a
pressure of 1.5-1.7 atm in the presence of
N2O5 / vanadium pentaoxide / Asbestos as
a catalyst. This reaction is reversible in
nature.
 2SO2(g) + O2(g) ⇌ 2SO3(g)

11. Cooled the gas
And passed through absorption chamber
Unreacted gas get back to catalytic
converter called chamber.

12. Step 3: Preparation of concentrated
sulphuric acid:
The cooled sulfur trioxide is dissolved in
98% sulfuric acid in the absorption tower.
 The acid is sprayed over the SO3 and
produces an oily liquid called oleum.
H2SO4 + SO3(g) → H2S2O7

13. Oleum tower is made up of brick- lined
steel.
This is preferable over directly dissolving
sulfur trioxide in water as this forms
sulfuric acid mists, due to the large heat of
dissolution (130 kJ/mol), which are hard to
control and difficult to store. Also it is
difficult to separate the sulfuric acid gas
from others such as nitrogen

14.  water is mixed with oleum to produce 98%
sulfuric acid
H2S2O7 + H2O → 2H2SO4

16. In Industries:
It is used in the production of phosphoric
acid which is in turn used to make
phosphate fertilizers.
It is used in the manufacturing of metals
such as copper, zinc etc.
It is used in the making of fibers.
Used in acidic drain cleaners.

17. As a Catalyst:
Used as a catalyst in the manufacturing
process of nylon.
Used in the Manheim process in the
manufacturing of HCl.
Used in petroleum refining.

18. Overview
This process contain several steps.
Carried out in large lead lined chamber.
SO2 is obtained by burnig suphur in
burner.
S + O2 → SO2
4 FeS2 + 11 O2 → 2 Fe2O3 + 8 SO2

19. It is also obtained from gysum. Because
gypsum is available in pakistan .
Sulphur dioxide passes through lead
chamber in the presence of O2, NO, NO2
along with steam.
SO2 is converted into H2SO4.
Acid is 60-70% H2SO4.

20. The plant employed in this process consist
of :
1. Pyrite burners
2. Nitre pots
3. Glover towers
4. Lead chambers
5. Gay-lussac tower
6. Coolers
7. Purification of acid chamber

21. Combustion of sulphur or sulphites is
carries ourt in a machenical furnace or the
flash roaster.
Here the S is coverted into SO2.

22. Contain the mixture of NaNO3 and H2SO4 .
Tower is about 15 into 50 feet .
Lined with acid proof cement.

23. oxide of nitrogen is obtained by heating
NaNO3 and concentrated H2SO4.
 NaNO3 + H2SO4 (concentrated) ——-> NaHSO4 + HNO3
 4 HNO3 —–> 2H2O + NO2 + O2
 4 HNO3 ——> 2H2O + 4NO + 3O2

24. Major Function of glover rower are :
1. Cooling the gases coming from pyrite burner
2. Conversion of some SO2 into SO3.
3. Concentrate the dilute acid.
4. Recovery of oxides of nitrogen from gay-lussac
tower.
5. Cleaning the burner gases.

25. Box like room made up of sheet lead.
No. of chmaber contain between 3-12.
The gases from previous chamber enter in
lead chamber at 99 *C
Chamber controlled through gase colour
changes and through temprature.

26. Afford space and time for reaction.
Conversion of SO2 into SO3.
To radiate heat produced by chemical
reaction.
Furnished surface for condensation of the
acid mist formed.

27. Filled with tile with tile packing.
Provide maximum area for contact.
Also recover oxides of nitrogen coming
from gases coming from lead chamber.

28.  Consist No. of tanks ( at least three ).
 Set in series made up of sheet leads.
 Coils of lead pipes have cooled water in it.
 Firstly acid from glover tower enter the first
cooler at 130-150 *C
 The temprature of acid remains only 30-4- *C
at the end.

29. Chamber acid usually used for
1. Fertillizers
2. Pickling of iron
3. In paints etx
 Chamber acid contain small amount of
lead, oxides of nitrogen, iron or aluminium
dissolved from tower.

30. Dossolved oxides of nitogen are removed
by adding 0.2-0.5 % ammonium sulphate
and heating .
 (NH4)2SO4 + NO + NO2 ——-> 3N2 + H2SO4 + 3H2O