2. INTRODUCTION
PRODUCTION
PROPERTIES
USES
MANUFATURING PROCESS
ADVANTAGES DISADVANTAGES
WASTE MANAGEMENT
SAFTEY
3. sulphuric acid is a colourless dense oily corrosive
liquid produced by the reaction of sulphur trioxide
with water and used in accumulators and in the
manufacture of fertilizers, dyes, and explosives.
Formula: H2SO4
4. 9th century: Islamic physician and alchemsit Ibn Zakariya
al-Razi – discovered dry distillation of vitriol (al-zajat), and
alcohol(ethanol).
17th century: German-Dutch chemist Johann
Glauber – burned sulphur with
saltpeter (potassium nitrate - KNO3)
18th century: Joseph Gay-Lussac, John Glover –
lead chamber process
19th century: Peregrine Phillips – contact process
6. King of compounds
Oil of vitriol
Dipping acid
Battery acid
Electrolyte acid
Mattling acid
Dihydrogen sulphate
7.
8.
9.
10.
11. Sulphuric acid acts as a catalyst in the
following reactions:
C1 2H22O11 + H2SO4 12C + 11H2O
The dehydrating ability of sulfuric acid is
often utilised in laboratories to dry gas
mixtures that are being prepared or
analysed.
12.
13.
14.
15.
16.
17. 75% of the SulfuricAcid that is produced is used to make
fertilizers such as
Superphosphate
Ammonium sulphate and
Ammonium phosphate.
Rock phosphate contains insoluble Calcium Phosphate .To
be made available to plants it needs to be converted to a
soluble form:
Ca3(PO4)2, (s) + 2H2SO4 (l) + 4H2O
Ca(H2PO4)2 (s) + 2CaSO4 • 2H2O
(s)
25. There are three industrial processes for
manufacturing of sulphuric acid.
Contact process
Lead chamber process
Wet Sulfuric Acid Process (WSA)
29. Sulphurdioxide burner gas contains impurities like
CO2 , As , F , N2 , Cl2 and dust.
Also contain moisture which can cause corrosion to
equipment.
To remove all these impurities the burner gas is
passed through dust filter chamber ,washing tower
and then drying tower
Dust filter chamber Washing tower Drying tower
35. The conversion of SO2 into SO3 is and exothermic
reaction .
It releases -197 kj per mole energy
To remove this extra heat coolers or heat
exchangers are adjusted on the outlets of reaction
bed
The temperature in the converter is maintained
between 400°C and 500°C and the pressure is close
to 1 atm.
36. Using Le Chatelier’s principal, the equilibrium
yield of sulfur trioxide will increase:
▪ As temperature decrease. Since the reaction is
exothermic a decrease in temperature will favour
the forward reaction.
▪ As pressure increases. Since there are more gas
particles on the reactants the forward reaction will
result in a decreased pressure.
▪ If excess reactants are added.
37. Direct reaction of SO3 with water is very exothermic which results
in the formation of steam .sulphuric acid as gas is very difficult to
collect .
SO3(g) + H2O(l) H2SO4(l) H= -103kjper mole
Due to this SO3 is absorbed in H2SO4 to produce oleum
SO3 (g)+ H2O (l ) H2S2O7(l)
38. Oleum is mixed with water to form sulphuric
acid
H2S2O7 + H2O 2H2SO4
39.
40.
41.
42. ADVANTAGES
Larger amount of sulphuric acid is manufactured
High concentraion of sulphuric acid is obtained as compared
to all other processes
Widely used
DISADVANTAGES
The biggest problem is that the catalyst can be poisoned if
the sulfur dioxide is not fairly pure. Also it could be faster.
43. Advantages
There are little or no waste by-products produced by this
process. It is also the most economic way to get rid of
sulfurous waste gases.
Disadvantages
This process produces an acid with low concentration
instead of the high concentrations that the Contact Process
yields.
44. Advantages
The original acid to be used can be obtained at any
concentration.
Disadvantages
The acid in the chamber is between 62% and 68% sulfuric
acid.
This process is not used as widely as the Contact Process is
today mainly because this process produces a more dilute
acid than the Contact Process which yields pure sulfuric acid.
The Contact Process also produces a much larger amount of
sulfuric acid than the Lead Chamber Process.
45.
46. Sulfuric acid plants use sulfur or sulfur dioxide that is a
by-product from other industries.
To maximise their conversion of sulfur dioxide to sulfur
trioxide most plants now use a double absorption
process.
Any unreacted gas from the absorption tower is
passed over the catalytic beds again and re passed
through the absorption tower.
This improves the percentage of sulfur dioxide
converted from 98% to better than 99.6%
47. Improvements in conversion have also been
made by adding small amounts of caesium
to the vanadium oxide catalyst to increase
its efficiency and allow it to operate at lower
temperatures
48. There is relatively little solid waste produced
from sulfuric acid manufacturing.
The catalyst is dumped in landfill after
recovering the mildly toxic vanadium.
The cooling water is recycled.
Most sulfuric acid plants are located near
smelting and refining industries that produce
waste sulfur dioxide, a raw material for the
production of sulfuric acid
49. All three processes are exothermic, meaning energy is
produced.The heat released is bring to boilers to produce
steamThis energy is used to generate its electricity or as a
source to produce other chemicals.
50.
51. Monitoring of Mist Emissions in the Stack
Emissions from S.A. plants generally consist of some
unconverted SO2, unabsorbed
SO3, and acid mist escaping from demisters installed in final
absorption tower.
These are minimized by the following techniques:
• Providing a continuously operating alkali scrubber for SCSA
plants.
• Using a DCDA process instead of SCSA and cesium
promoted catalyst in the last
pass of the converter.
• Strict control of process temperatures and SO2
percentages in gases at the inlet to the converter.
52. • Use of efficient hot gas filters and sulfur filters to
minimize the deposition of ash
on the catalyst surfaces.
• Automatic adjustment of dilution water addition
to control the strength of the
circulating acid at optimum level (98.0–98.5%).
• Control of temperatures of acid and gas at the
inlet to the absorption towers.
• Sufficient flow of acid in all towers.
53. The SO3 vapors generated by the oleum boiler should be
condensed or absorbed
into a suitable medium.Apart from well designed,
fabricated, tested, and maintained
storage and condenser plant, operators will find the
following practical suggestions
useful for safe operation:
1. Use only pureTeflon PTFE gaskets in SO3 vapor and liquid
lines. Conventional
acid resistant gaskets may not be able to withstand attack by
SO3.
54. 2. Provide steam tracing lines, i.e., another steam line in
contact with or in the near
vicinity of the liquid SO3 pipeline instead of a steam jacket.
3. Maintain a temperature of between 28 and 33 °C in the
storage tanks for SO3.
4. Provide a dual pressure gauge on the SO3 condenser,
which can indicate pressures
below and above atmospheric.
5. Use a falling film condenser instead of a shell and tube
type condenser wherein
cooling water flows under pressure in the tubes.
55. In the case of a tube leak, no water should enter the SO3
side.The tubes in the
falling film condenser are open to the sky and, in the case of
a leak, the pressure
gets released to the top opening.
6. Safety vents, rupture discs, and air vents will form
standard mountings on the
condenser and storages. Scrubbers will be connected to the
vents and irrigated by
98% sulfuric acid for absorbing any SO3 vapors released
from the vents.
56. Sulfuric acid is highly corrosive and can burn skin
and eyes severely.
It can cause blindness and third degree burns on
contact.
Exposure to sulfuric acid mist can cause other health
problems.
Workers in sulfuric acid plants can also be exposed
to the acid through breathing air contaminated with
emissions containing oxides of sulfur
57. Strict safety procedures including adequate
methods to trap the fumes are required to minimise
the risks to workers and the environment in the case
of accidently release
Work areas must be well ventilated and employees
wear protective clothing.
Acid spills are contained using materials such as
earth, clay or sand and then slowly diluted with
water before being neutralised with a base such as
limestone or sodium carbonate