2. CONTEXT
➢ INTRODUCTION
• Definition
• Formula and Structure
• synonyms
• Occurrence
➢PROPERTIES
• Chemical
• Physical
➢USES
• Industrial Uses
• Consumer Uses
➢Manufacturing Methods
• From salt and calcium carbonate (via the ammonia
soda (Solvay) process)
• from sodium carbonate and hydrogencarbonate ores
(trona and nahcolite)
➢ list of companies offering Sodium
Carbonate Washing Soda in Pakistan
➢ REFRENCES
3. INTRODUCTION
➢ Definition
Sodium Carbonate is the disodium salt of carbonic acid with alkalinizing
property. When dissolved in water, sodium carbonate forms carbonic acid and
sodium hydroxide. As a strong base, sodium hydroxide neutralizes gastric acid
thereby acting as an antacid
• Sodium carbonate is known as washing soda or soda ash. It is commonly
occurred as a crystalline hepta-hydrate which readily effloresces to form a
white powder, the monohydrate.
• Pure sodium carbonate is a white, odorless powder that is hygroscopic
means it absorbs moisture from air. It has a alkaline taste and forms a
strongly alkaline water solution
4. FORMULA & STRUCTURE
• The chemical structure of sodium carbonate is Na2CO3, and its
molar mass is 106.0 g/mol. Sodium carbonate is an ionic
compound- a sodium salt of carbonic acid, and is composed of two
sodium cations (Na+) and a carbonate anion (CO3
-). It has a
crystalline heptahydrate structure.
➢MOLECULAR FORMULA
Na2CO3· nH2O (n = 0, 1 or 10) or Na2CO3 or CNa2O3
6. SYNONYMS
➢Depositor-Supplied Synonyms
1. SODIUM CARBONATE 11. Solvay soda
2. Disodium carbonate 12. Carbonic acid sodium salt (1:2)
3. 497-19-8 13. Soda, calcined
4. Soda Ash 14. Light Ash
5. Carbonic acid disodium salt 15. V Soda
6. Calcined soda 16. Bisodium carbonate
7. Sodium carbonate, anhydrous 17. Sodium ash
8. Carbonic acid, disodium salt 18. Sodium carbonate anhydrous
9. Washing soda 19. Na2CO3
10.Sodiumcarbonate 20. Sodium carbonate (2:1)
7. OCCURANCE
➢Sodium carbonate occurs naturally in mineral form as its hydrate
salts (such as trona, natron, natrite, etc.). There are several of its
mineral deposits found in dry regions around the world.
➢The Solvay process provides most sodium carbonate for industrial
use. It is found in large natural deposits and is mined in Wyoming;
it is also recovered (with other chemicals) from lake brines in
California.
8. PROPERTIES
➢PHYSICAL PROPERTIES:
❑Molecular Weight: 105.988 g/mol
❑Color: Grayish-white powder
❑Odor: Odorless
❑Taste: Alkaline taste
❑Boiling Point: Decomposes
❑Melting Ponit: 851°C
❑Density: 2.54 g/cu cm
❑Stability: Stable at ordinary temperature and atmospheric
conditions; dries out somewhat in warm, dry air or above 50
deg C
9. PROPERTIES
➢CHEMICAL PROPERTIES
❑Sodium carbonate is a stable but hygroscopic solid (absorbs
water from air) and readily dissolves in water to form weakly
acidic carbonic acid and the strong base, sodium hydroxide.
❑ Thus, the aqueous solution of Na2CO3 is overall a strong base.
It reacts violently with many acids. When heated to high
temperatures, it decomposes to emit toxic fumes of disodium
oxide (Na2O).
10. USES
Soda ash is the trade name for sodium carbonate, a chemical
refined from the mineral trona or sodium-carbonate-bearing brines
(both referred to as "natural soda ash") or manufactured from one
of several chemical processes (referred to as "synthetic soda ash").
It is an essential raw material in glass, chemicals, detergents, and
other important industrial products. In 1998, in terms of production,
soda ash was the 11th largest inorganic chemical of all domestic
inorganic and organic chemicals, excluding petrochemical
feedstocks. Although soda ash represented only 2% of the total $39
billion U.S. nonfuel mineral industry, its use in many diversified
products contributed substantially to the gross domestic product of
the United States. Because soda ash is used in flat glass for
automobile manufacture and building construction, which are
important economic sectors of the domestic economy.
11. USES
➢INDUSTRIAL USES
1. Adsorbents and absorbents
2. Bleaching agents
3. Fillers
4. Finishing agents
5. Intermediates
6. Lubricants and lubricant
additives
7. Oxidizing/reducing agents
8. Pigments
9. Process regulators
10.Processing aids, not otherwise
listed
11. Processing aids, specific to
petroleum production
12. Solids separation agents
13. Solvents (which become part of
product formulation or mixture)
12. USES
➢CONSUMER USES
• Air Care Products
• Building/Construction Materials not covered elsewhere
• Food Packaging
• Laundry and Dishwashing Products
• Lubricants and Greases
• Metal Products not covered elsewhere
• Personal Care Products
• Water Treatment Products
13. MANUFACTURING METHODS
➢SOLVAY PROCESS:
➢HISTROY:
➢In 1861, after realizing the polluting impacts of the Leblanc Process, Belgian
industrial chemist Ernest Solvay rediscovered and perfected Augustin Fresnel's
reaction. This process recovered the ammonia in the reaction for re-use, therefore
making it less detrimental to the environment.
➢ In 1874, other companies had bought the right to use the Solvay process in their own
plants. Now the sodium carbonate production market became a booming industry
with several plants opening worldwide.
➢In 1890's, Solvay-based process plants produced the majority of the world's soda ash.
➢ The materials needed in the Solvay process are nearly all readily available and
inexpensive:
14. Raw Material
❑ The Raw materials which are required for this
process are:
➢Sodium Chloride (NaCL)
➢Lime Stone (CaCO3 )
➢Ammonia gas (NH3 )
15. THE STEPS IN SOLVAY PROCESS
1.Brine Purification
2.Formation of sodium Bicarbonate
3.Formation of sodium carbonate
4.Ammonia Recovery
17. BRINE PURIFICATION
• At first stage a saturated solution of sodium chloride is prepared
which is also known "BRINE".
Composition of solution of NaCl (brine) is 28% m/m.
• Brine is concentrated by evaporation. Impurities such as calcium,
magnesium and iron are removed by precipitation
• sodium chloride brine is first purified to prevent scaling of
downstream process equipment and to prevent contamination of
the final product. Magnesium ions are precipitated with milk of
lime, Ca(OH)2, and the calcium ions are precipitated with soda
ash
18. BRINE PURIFICATION
• For example:
• Ca+2(aq) + CO3
-2(aq) ——–CaCO3(s)
• Mg+2(aq) + 2OH–(aq) ——mg(OH)2(s)
• Fe+3(aq) + 3OH–(aq) ——Fe(OH)3(s)
• After removing the impurities Brine solution is then filtered and
passed through an ammonium tower to dissolve ammonia. After
purification, the brine solution is contacted with ammonia gas .
19. IMPORTANT POINT TO REMEMBER
➢This process is exothermic it’s mean ammonia is
cooled.
20. FORMATION OF SODIUM BICARBONATE
▪ The ammoniated brine is then sent to the carbonating columns
where sodium bicarbonate is precipitated by contacting the brine
with carbon dioxide.
▪ Sodium bicarbonate is less soluble and precipitates on the internals
of the carbonating column.
▪ At the end of the make cycle, the slurry is drained and the solid
bicarbonate is filtered. ... The slurry from the carbonating columns
is fed to continuous vacuum filters or centrifuges where the sodium
bicarbonate crystals are recovered
21. CHEMICAL REACTION OF SODIUM BICARBONAT
• Carbon dioxide is produced by the thermal decomposition of limestone.
• CaCO3——-à CO2+CaO
• Carbon dioxide is bubbled through the ammoniated Brine Solution in the
carbonating tower.
• The carbon dioxide dissolves to form a weak acid:
• CO2(g)+H2O(l)↔HCO3(aq)+H+(aq)
• The ammonia in the brine reacts with H+ to form Ammonium ion.
• NH3+H+↔NH4
+
• The bicarbonate ion reacts with Na+ to form sodium Hydrogen carbonate
(sodium bicarbonate).
• Na++HCO3
–↔NaHCO3(s)
• Sodium bicarbonate precipitates
• NH3(aq)+CO2+NaCl+H2O↔NaHCO3+NH4Cl
22. FORMATION OF SODIUM CARBONATE
• The suspended sodium hydrogen carbonate is
removed from the carbonating tower and heated
at 300°C to produce sodium carbonate.
• 2NaHCO3——–Na2CO3+CO2+H2O
• This CO2 is recycled back into the carbonating
tower.
23. AMMONIA RECOVERY
Calcium oxide which was formed as a byproduct of
the thermal decomposition of limestone in the lime
kiln, react with water to form calcium hydroxide
CaO(s)+ H2O(l)——– Ca(OH)2 (aq)
This calcium hydroxide reacts with ammonium
chloride separated out of the carbonating tower by
filtration.
Ca(OH)2+2NH4Cl—- CaCl2+2H2O+ 2NH3
The ammonia is recycled back into the process to
form ammoniated brime.
Calcium chloride is formed as a by-product of the
solvey process.
26. ➢A series of refining steps are required to produce soda ash from
trona ore
• First the raw ore from the mine is crushed and screened.
• The material is then fed to rotary calciners and heated. In this
process, the trona decomposes to form crude soda ash, which is
dissolved in water.
• The insoluble shales are separated from the solution by a
combination of settling and filtration steps and the resulting
insoluble tailings are taken back into the mine as backfill
• The soda ash solution is treated to remove organic materials
yielding a high-purity saturated solution of sodium carbonate.
SODIUM CARBONATE PRODUCED BY TRONA
27. SODIUM CARBONATE PRODUCED BY TRONA
• Next, the solution is fed to crystallizers where water is evaporated
and sodium carbonate monohydrate crystals are formed. The
industry-familiar term “mono-process” originates from this
process step
• The crystals are dewatered and washed using cyclones and
centrifuges, and the solution is recycled to the evaporator units
for further recovery of soda ash
• The monohydrate crystals are fed to rotary kilns where they are
dried to finished soda ash.
• Finally, product is screened and sent to storage silos awaiting rail
and truck loadout.
28. list of companies offering Sodium Carbonate
Washing Soda in Pakistan
➢ AL-NAWAB ENTERPRISES
❖ 53-Jaranwala Road,Near Purani Chungi , Faisalabad
➢ ATLANTIS PUBLICATION
❖ #A-36,Eastern Studio Compound,Plot #B-16,S.I.T.E. , Karachi
➢ CHAMAN CHEMICAL INDUSTRIES (PVT) LTD
❖ 25-A/1,Davis Road , Lahore
➢ FUTEHALLY CHEMICALS (PVT) LTD.
❖ D-86,Manghopir Road,S.I.T.E. , Karachi
➢ NOVA COLOUR & CHEMICAL CO.
❖ H.O.: 25,New Anarkali,Opp. Muhafiz Plaza , Lahore
