PROJECT PRESENTATION - PHASE 1 Phase 2 http://www.slideshare.net/AnkushGupta40/phase23

1. 1
PROJECT TOPIC
MANUFACTURE OF CHLORINE–
CAUSTIC
SODA USING ELECTROLYSIS
PROCESS
BHARATI VIDYAPEETH
COLLEGE OF ENGINEERING
CHEMICAL DEPARTMENT
Prof. R.K.Kulkarni
Presented by
Ankush Gupta
Aviral Kandpal
Sushant Mali

2. Introduction to Caustic soda / Chlor
2
Alkali Industry
• The Chlor-Alkali industry in India forms an important component of
basic chemicals industry ,comprising around 74% of the basic
chemicals production in India.
• The Chlor-Alkali Industry in the country produces mainly Caustic
Soda, Chlorine and Soda Ash.
• The geographic distribution of Chlor-alkali processes world-wide
differs appreciably (production capacity of chlorine):
-western Europe, predominance of mercury cell process (June
2000): 55%
-United States, predominance of diaphragm cell process: 75%
-Japan, predominance of membrane cell process: >90%

3. 3

4. PROPERTIES OF CHLORINE-CAUSTIC
4
SODA-HYROGEN
CAUSTIC SODA
Physical State Solid.
Appearance White pellets.
Odor Odorless.
Vapor Pressure 1 mm Hg @ 739 CO
Boiling Point 1390 CO @ 760 mm Hg
Freezing/Melting Point 318 CO
Solubility Soluble.
Specific Gravity/Density 2.13 g/cm3.
Molecular Formula NaOH.
Molecular Weight 40.00
PH 14 (5% aq soln).

5. 5
CHLORINE

6. 6
HYDROGEN
APPEARANCE AND STATE Colorless gas at normal temperature and
pressure
ODOR Odorless
MOLECULAR WEIGHT 2.016
BOILING POINT (1 atm) 423.0 _F (-252.8 _C)
SPECIFIC GRAVITY (Air =1) 0.06960
FREEZING POINT/MELTING POINT -434.5 °F (-259.2 _C)
GAS DENSITY (At 70 F (21.1 C) and 1 atm): 0.00521 lb/ft3(0.08342 kg/m3)
SOLUBILITY IN WATER (Vol/Vol at 60 F (15.6
0.019
C)
SPECIFIC VOLUME (At 70 F (21.1 C) and 1 atm 192 ft3/lb (11.99m3/kg)

7. 7
LITERATURE SURVEY

8. 8
SERIA
L NO
NAME OF AUTHOR YEAR OF
RESEARCH
RESEARCH TOPIC DESCRIPTION
1 S.koter.A.warszaws
ki
2008 Electromembrane
process in environmental
protection
Use of bipolar membrane is
emphasized.recovery of
valuable chemicals from
effluents& waste gases
Application of ion exchange
membrane “green” power
source is also discussed
2 yohannes kiros
&martin bursell.
2008 Low energy consumption
in chlor alkali cells using
oxygen reduction
electrodes
Gas diffusion electrode for
use as a cathode to
replace the traditional
hydrogen evolving
electrode in chlor-alkali
electrolysisProblems
associated with ‘flooding’
or‘wetting’ are minimised
by attempt to stablize
cathode

9. 9
SERIAL
NO
NAME OF
AUTHOR
YEAR OF
RESEARCH
RESEARCH TOPIC DESCRIPTION
3 Babatope
A.olufemi,willia
ms o.ozoute &
ololane
o.komolafe
2011 Studies on production
of caustic soda using
solar powered
diaphragm cells.
The research served as an
encouraging inquistive foundation
into possibility of producing
caustic soda directly from solar
powered electrolytic diaphragm
cells in comparison with present
conventional modes of
electrochemical production .
4 K.juttner,u
galla,h
schmieder
2008 Electrochemical
approaches to
environmental
protection in process
industry
•. Protection of environment
through implementation of
effluent treatment productio
integrated process for
minimization of waste and
toxic
•Anode destruction of organic
pollutants and new
electrochemical abatement
techniques for purification of
the gaseS

10. 10
SERIAL
NO
NAME OF
AUTHOR
YEAR OF
RESEARCH
RESEARCH TOPIC DESCRIPTION
5 Subrata Basu,
Swapan Kumar
Mukhopadhyay,
Amitava
Gangopadhyay
and Sujata G.
Dastidar
2013 Characteristic Change
of Effluent from a Chlor-alkali
Industry of
India due to Process
Modification
The main focus of this paper
is on the evaluation of waste
minimization at source due to
process modification. The
possible
improvement of the treatment
of effluent is also duly
considered.
6 A. Rezaee, J.
Derayat, ,S.B.
Mortazavi, Y.
Yamini and M.T.
Jafarzadeh
2005 Removal of Mercury
from chlor-alkali
Industry Wastewater
using
Acetobacter xylinum
Cellulose
•The removal of mercury ions
by cellulose of Acetobacter
xylinum was
investigated in the synthetic
and chlor-alkali wastewater.
•Efficiency of
mercury ion removal from
chlor-alkali industry
wastewater by aluminum
sulfate and ferric
chloride was also determined.

11. Competitive Manufacturing
11
Process
• There are 3 types of electrolytic
processes used in the production of
chlorine:
(1) The diaphragm cell process
(2) The mercury cell process
(3) The membrane cell process
• A salt solution is electrolyzed by
the action of direct electric
current that converts chloride ions
to elemental chlorine. The overall
process reaction is:
In all 3 methods, the chlorine is
produced at the positive electrode
(anode) and the caustic soda and
hydrogen are produced, directly or
indirectly, at the negative electrode
(cathode).

12. The Diaphragm cell process
12

13. 13
FEATURES
DIAPHRAGM CELL
• In the diaphragm cell process, there are two
compartments separated by a permeable diaphragm.
• Brine is introduced into the anode compartment and
flows into the cathode compartment.
• Similarly to the Membrane Cell, chloride ions am
oxidized at the anode to produce chlorine, and at the
cathode, water is split into caustic soda and hydrogen.
• The diaphragm prevents the reaction of the caustic soda
with the chlorine.
• A diluted caustic brine leaves the cell.
• The caustic soda must usually be concentrated to 50%
and the salt removed. This is done using an evaporative
process.

14. The Mercury cell process
14

15. 15
FEATURES
MERCURY CELL
• Electric current flowing through the cell decomposes the brine passing
through the narrow space between the electrodes, liberating chlorine
gas at the anode and metallic sodium at the cathode
• The chlorine gas is accumulated above the anode assembly and
discharged to the purification process.
• As it is liberated at the surface of the mercury cathode and the sodium
immediately forms an amalgam (a 'mixture' of two metals)
• The liquid amalgam flows from the electrolytic cell to a separate
reactor, called the decomposer, where it reacts with water in the
presence of a graphite catalyst to form caustic soda (sodium hydroxide)
and hydrogen gas.
• The sodium-free mercury is fed back into the electrolyser and reused.

16. The membrane cell process
16

17. 17
FEATURES
MEMBRANE CELL
• This technology uses water-impermeable ion-conducting membrane.
• The membrane is made of a special resin which permits cations
(positive ions) to pass through.
• The anode chamber of a membrane electrolytic cell is filled with
brine, and the cathode chamber with water.
• These ions migrate when a current is applied: the positively charged
sodium ions pass through the membrane to the cathode chamber,
while the negatively charged chloride ions are discharged on the
anode surface to form chlorine gas .
• Water in the cathode chamber partly dissociates into hydrogen and
hydroxide ions.
• The hydrogen ions capture electrons on the cathode surface to form
hydrogen gas.
• The hydroxide ions are attracted to the anode, but blocked by the
membrane, and react with the sodium ions from the anode chamber
to form caustic soda (sodium hydroxide, NaOH)

18. SELECTION OF THE PROCESS
18
MEMBRANE CELL PROCESS
• The membrane cell process has inherent
ecological advantages over the two older
processes, as it does not use mercury or
asbestos.
• It is the most energy efficient process.
• It is extremely safe to operate it and it produces
a consistently high quality of caustic soda.

19. 19

20. 20

21. 21
Thermodynamic Feasibility
• The standard free energy, ΔGº tells us the thermodynamic
feasibility of a reaction. Since the standard electrode
potential of a reaction, E° and ΔG° are intimately linked;
one can use the standard electrode potentials of a reaction
to calculate the thermodynamic feasibility of a reaction.
ΔGo= -nFEo
n= no of electrons transferred
F= Faraday constant = 96630 J/V.mol
Eo = Cell voltage
So, ΔGo = -1*96630*6  -579780 J/mol
ΔGO << 0
SO THIS REACTION IS FEASIBLE

22. PROCESS FLOW DIAGRAM
22

23. 23
Pressure & Temperature
Combinations for condensing gas
•High pressure (7-10 atms), water cooling
•Medium pressure (2-3 atms), Refrigeration at
- 20oC
•Low pressure (5-10 cm H2O), Refrigeration at
-400C

24. 24
Quantitative Requirements
• Basis of Product : 1 ton of Cl2 ; 1.15 tons of NaOH(98%) .
• Plant capacities : 100-1000 tons/day of Cl2 in a series of electrolysis
units each producing 0.5 – 2 tons Cl2 per day
Sulphric Acid (98%) 5-6 kg
Sodium hydroxide 10-15 kg
Steam 11 tons
Electricity 2900 KWH

25. 25
• DIAPHRAGM CELL TYPE
• Anode : Cl - - e  ½ Cl2
• Cathode: Na+ H2O + e  Na+ + OH- + ½ H2
• Overall: NaCl + H2O  NaOH + ½ H2 + ½ Cl2
• MERCURY CELL PROCESS
• Anode: Cl- - e  ½ Cl2
• Cathode: Na+ + e  Na
: Na + Hg  NaHg(amalgam)
• Denuding: NaHg + H2O  NaOH + ½ H2 + Hg
• Overall: NaCl + H2O  NaOH + ½ H2 +Cl2
• 2NaCl + 2H2O  2NaOH + H2 +Cl2

26. 2NaCl + 2H2O  2NaOH + H2 +Cl2 (58.5) (18)
26
(40) (2) (70)
( 28.75) (28.75) (28.75) (14.375) (14.375) Kmoles
(1681.8) (517.5) (1150) (28.75) (1006) Kg
• Sample calculation
Moles = weight / molecular weight
For NaCl
Moles = 1150/40  28.75 Kmol
NaCl formed (Kg) = 28.75 * 58.5  1681.8 kg (1700 Kg).

27. 27
Factors affecting Plant location
• Adequate Supply of Raw materials.
• Proximity to the market — Minimum supply time. Relative cost low
(one third of caustic plants are attached to paper and rayon mills).
• Transport Facilities — Good capacity and speedy transportation.
• Supply of Labor — Cheap Labor Supply.
• Power— Regular Power Supply for operation machinery at full
capacity.
• Supply of Capital — Required for Initial promotion and Expansion.
• Natural Factors — Land, Water, Climate(Agriculture based
Industries).
• Political Factors — Favorable Development Policies.
• Government Subsidies — Exemptions, Rebates and Subsidies.
• Historical and religious factors.
Need careful analysis of such factors as cheap power and salt sources
coupled with risisng cost of transportation.

28. 28
Locations of caustic soda plants
NAME PROCESS USED
Durgapur Chemicals Ltd
Mercury cell
(Durgapur W.B)
J.K Chemicals Ltd ,thane
(Maharastra)
Mercury cell
Sirpur Paper mills ,sirpur
khaghaz nagar(A.P)
Diaphragm cell
Chemfab Alkalies ltd
(pondicherry)
Membrane cell
Rohtas Industries ltd ( bihar) Mercury cell

29. REFERENCES
1 ) Subrata Basu , Swapan Kumar Mukhopadhyay , Amitava
Gangopadhyay and Sujata G. Dastidar “International Research
Journal of Environment Sciences Characteristic Change of Effluent
from a Chlor-alkali Industry of India due to Process Modification”
2013.
2) S.Koter.A.Warszawski “Polish Journal of Environmental Studies
Electro- membrane Processes in Environment Protection” (2000)
3) Yohannes Kiros and Martin Bursell “International Journal
Electrochemistry Science Low Energy Consumption in Chlor-alkali
Cells Using Oxygen Reduction Electrodes (2008)”
4) Rezaee, J. Derayat, S.B. Mortazavi,Y. Yamini and M.T. Jafarzadeh
“American Journal of Environmental Sciences Removal of Mercury
from Chlor-alkali Industry Wastewater using Acetobacter xylinum
Cellulose(2005)”
29
5) Dryden’s outlines of chemical technology (2012)