Manufacturing of detergents

1. Chapter- II Detergents and Cosmetics
 Sodium salts of long chain benzene sulphonic acid.
 Primarily surfactants, produced from petrochemicals.
 Surfactants lower the surface tension of water,
essentially making it 'wetter‘.
So that it is less likely to stick to itself, and more
likely to interact with oil and grease.
 The ionic group is in a detergent is SO3
-Na+.

2. Sodium alkyl sulphate
Sodium alkylbenzene sulphonate
Glycerol based (non-ionic
surfactant/detergent)

3. ADVANTAGES OF DETERGENTS
• Since detergents are the salts of strong acids, they do not decompose
in acidic medium. Thus, detergents can effectively clean fabric even if
the water is acidic.
• Synthetic detergents are more soluble in water than soaps.
• They have a stronger cleansing action than soaps.
• As detergents are derived from petroleum they save natural vegetable
oils, which are important to use as essential cooking medium.

4. DIFFERENCES BETWEEN SOAPS AND DETERGENTS
SOAPS
 They are metal salts of long
chain higher fatty acids.
 These are prepared from
vegetable oils and animal fats.
 They cannot be used
effectively in hard water as
they produce scum i.e.,
insoluble precipitates of Ca2+,
Mg2+, Fe2+ etc.
DETERGENTS
 These are sodium salts of long
chain hydrocarbons like alkyl
sulphates or alkyl benzene
sulphonates.
 They are prepared from
hydrocarbons of petroleum or coal.
• These do not produce insoluble
precipitates in hard water. They are
effective in soft, hard or salt water.

5. Manufacturing of Detergents
 They are made both in powder and liquid form, and sold as laundry
powders, hard surface cleaners, dish washing liquids, fabric
conditioners etc.
Detergent powder manufacture
Step.1 Slurry making: The solid and liquid raw ingredients are dropped
into a large slurry mixer tank or clutcher.
 The ingredients mixture heats up to undergo two exothermic reactions:
hydration of sodium tripolyphosphate and the reaction between caustic
soda & linear alkylbenzene sulphonicacid.
 The mixture is further heated to 850C and stirred until it forms a
homogeneous slurry.

6. Step.2 Spray drying
 The slurry is deaerated in a vacuum chamber and separated by an
atomiser into finely divided droplets.
These are sprayed into a column of air at 425oC, where they dry
instantaneously. The resultant powder is known as ’base powder’.
Step.3 Post dosing: Other ingredients are added, and the air blown
through the mixture in a fluidizer to mix them into a homogeneous
powder. Flow diagram and typical ingredients are:

7. Flow diagram: Manufacturing of Detergents by spray drying

8. Table : Base powder ingredients and their functions

9. Surfactants
 A surfactant (surface active agent) is a compound with a water-soluble
oil-insoluble (hydrophilic) portion on one side and an oil-soluble
water-insoluble (hydrophobic) portion on the opposite side.
 Generally, the hydrophobic portion is a long alkyl chain while the
hydrophilic portion is a solubility-enhancing portion.
 The surfactant exhibits surface activity by lowering the surface tension
of liquids.
• anionic
• cationic
• nonionic and amphoteric
Classification of surfactants: Four classifications

10. Anionic surfactants
These include alkylbenzene suphonates, fatty alcohol sulphates (alkyl
sulphates) and alkyl ether sulphates.
- Compounds in which the detergency is realized in the anion.
R-SO3
- Na+ Alkylsulfonates
Cationic surfactants
- Compounds in which the detergency is in the cation.
- No neutralization takes place. R2N+(CH3)2Cl-
e.g., Dialkyl dimethylamonium chlorides

11. Non-ionic surfactants
Contains non-ionic constituents, RO-(CH2-CH2-O)nH
e.g., Alkyl poly(ethylene glycol) ethers, linear alkyl sullfonate (LAS)
and Tetra propylene benzene sulfonate (TPS)
Amphoteric surfactants:
Includes both acidic and basic groups in
the same molecule.

12. Preparation of Surfactants

13. Anionic surfactants: Secondary Alkanesulfonate (SAS)

14.  The majority of nonionic surfactants are condensation products of
ethylene oxide with a hydrophobe.
 This hydrophobe is invariably a high molecular weight material with
an active hydrogen atom.
 The nonionic material can be one of the reaction products.
• Fatty alcohol and alkylphenol condensates.
• Fatty acid condensates.
• Condensates of ethylene oxide with an amine.
• Condensates of ethylene oxide with an amide.
Nonionic surfactants

15. Fatty alcohol and alkylphenol condensates

16. Fatty acid condensates

17.  The Pharmaceutical Affairs Act defines cosmetics as:
"Articles with mild action on the human body, which are intended to
be applied to the human body through rubbing, sprinkling or other
methods, aiming to clean, beautify and increase the attractiveness,
alter the appearance or to keep the skin or hair in good condition."
 Cosmetics are classified into,
• "perfume" - fragrance,
• "makeup cosmetics“ - foundation creams, lipsticks and eye makeup,
• "skin care cosmetics" - facial cream, skin lotion, skin milk
• and cleansing cream,
• "hair care products" - hair dye, shampoo & hair treatment,
• "special-purpose cosmetics" - sunscreen.
Under the Act, soaps are classified as cosmetics.
Cosmetics