1. LUBE OIL ADDITIVES

2. LUBRICANTS Lubricants were in use before the invention of wheel.
Building block of 95% of today’s lubricants is mineral oil.
Straight run MO not satisfactory for operating under arduous conditions.
Modern Lubricant is highly refined HC base stock+chemical additives.

3. WORLD LUBRICANT USES 4 Automotive Transmissions 5 Grease 9 Process 27
Industrial 55
Engine %
APPLICATION

4. PERFORMANCE-WISE CLASSIFICATION OF ADDITIVES
Modifies crystal growth at low temperature
Pour Point Depressants
Improves viscosity – temp. relationships
Viscosity Index Improvers
Prevent formation of acid, minimize viscosity increase
Antioxidant
Reduce wear, minimize metal to metal contact
Antiwear/EP
Engine Cleanliness, keep sludge in suspension
Detergents Dispersants

5. PERFORMANCE-WISE CLASSIFICATION OF ADDITIVES
Control Foamings
Defoamant
Improves Adhesive Properties
Tackiness Agents
Neutralizes Catalytic Effect of Metals
Metal Deactivators
Prevent Corrosion of Ferrous and Non-ferrous surfaces
Corrosion/Rust/ Inhibitors
Reduce Friction between moving parts, improve engine efficiency
Friction Modifiers

6. DETERGENT/DISPERSANT ADDITIVE
Major Use in Crankcase Oil
Represent 70% of Total Additive Used in Engine Oil

7. FUNCTION OF DETERGENT/ DISPERSANT ADDITIVE
Keep Particulate matter dispersed
Maintain Engine Cleanliness
DIRT IN ENGINE ARISES FROM
Below-by of products from incomplete
combustion of fuel
Oil oxidation product
Engine wear
Dirt Leads to Deposit in Engine e.g. On Piston Known as Lacquer or Varnish on English Sump Known as Sludge

8. DETERGENTS Metal Containing Cleaning Agents
Capable of dealing deposits/precursor generated under high temperature running conditions

9. PARTS OF DETERGENT A metal Al, Mg, Zn, Ba, Ca.
An anionic component e.g.
carboxylate,
Alcoholate,
Phenate,
Sulphonate and
Salicylate.
Oil Soluble Oleo-philic Component Straight or Branched Alkyl Group.

10. TYPES OF DETERGENTS Sulphonate By-product of white oil Phenate
Salicylate
Phosphate
Neutral
Over Base
By-product of white oil
Synthetic From Alkyl Aromatic

11. OVER BASE ADDITIVES
Colloidal Disperson Of Metal Carbonate ( Micron)
TECHNOLOGY IS COMPLEX TO MAKE STABLE SUSPENSION
ESTIMATION
As TBN (500)
Metal Ratio
EFFECTIVE IN CONTROLLING
a) Corrosive Acid From Oil Oxidation
b) Blow-by Of Combustion Product

12. PREPARATION OF OVER BASE ADDITIVE
Phenate Over Base Are Prepared Similarly
Phosphates are Phosphoric And Thio Phosphoric Acid Derivatives

13. SELECTION DEPENDS ON Severity Of Condition Anti Rust Anti Oxidant
Load Carrying Properties

14. DISPERSANTS Non metallic ashless cleaning agents
Effective in controlling cold-sludge in gasoline engine operating under low-temp. stop-start conditions
Bipolar molecule having polar head non-polar tail
Head consist of P,O,N atoms
Tail HC moiety

15. ADDITIVES TYPES Succinimides Succinate Esters Mannich Type
Phosphorus Based

16. MECHANISM OF ACTION
Polar Group Absobs on Dirt Oliophillic Group Solubilize Complex in Oil
React Dirt Precursors e.g. neutralizing acidic matter
Solubilizing precursors within their micelle structure.
Absorb on metal surface
Form coating on solid particulate and prevent their agglomeration to form large particles.

17. USES OF DETERGENT / DISPERSANT ADDITIVES
Essential for most of automotive oils
Automotive oil for gasoline/diesel
Rail road engine oil
Marine Oil
Two stroke engine
Tractor Oil
Automatic Transmission Fluid

18. OXIDATION INHIBITOR (AO)
Lubricants like other natural products deteriorate during use when exposed to oxygen.
Undergo complicated aging process.
Oxidation alter performance.
1st oxidation product is hydroperoxides.
Hydroperoxide leads to variety of end products like alcohol, aldehyde, ketone acid etc.
Eventually depositing as sludge, varnish, liquer.
Leading to equipment failure

19. MECHANISM OF ACTION
R-H R` + H` R` + O ROO` Antioxidant perform as radical quenchers R` + AO RH + AO` 2 AO` INERT PRODUCTS

20. Engine oil accounts 60-70% of automotive lubricants.
40-50% of all lubricants sold
Automotive engine oil driving force on AO market
AV car temperature – 100o
Hot spot temperature – 300o or more
Chain branching reactions are more prevalent in high temperature oxidation.
For lube antioxidants is a mixture of peroxide destroyer (TDDP) and radical scavenger.

21. ADDITIVE TYPE Zn-Di-Thio phosphate Phenol Aromatic Nitrogen Compounds
S- and P- Based Antioxidants
Phenothiazine and Alkyl Derivatives

22. USES OF ANTIOXIDANTS Antioxidants are used in all type of Lubricant
Cranckase Oil Mostly Use ZDDP
Steam Turbine Hindered Phenol
Jet Air Phenothiazine Derivatives

23. OTHER COMPUNDS GENERALLY USED IN ADDITION TO ZDDP
HINDERED PHENOL
RO – P – H OR O
CH2 RO OH
DIPHENYL AMINE NH
C8H17
RO – P – OR OR N S R
PHENOTHIAZINE
DITHIOCARBAMATES
CNX2
S – M – S
X2NC S
X= Alkyl, Aryl, alkylaryl
ORGANIC SULPHIDE OR SLENIDES
(XOC – CH2 – CH2)2 S, X – S – X, or X – Se - X O

24. VISCOSITY INDEX IMPROVER AND POUR POINT DEPRESSANTS
These are polymeric additives
These additives are used to improve rheological properties of oils
They do it by purely physical means

25. VISCOSITY INDEX IMPROVER
VI is a number showing viscosity temperature characteristic of oil.
Gear, Transmission, Crankcase oil should have
(a) Low viscosity at low temperature for startup (need low friction drag)
(b) Sufficient viscosity at higher running temperature.

26. TYPES OF VI IMPROVERS Oil Soluble Org. Polymer
M wt range 50, ,000
(a) Hydrocarbons
(b) Esters

27. TYPES OF VI IMPROVERS HYDROCARBON TYPE PIB Poly-isobutylene
OCB Olefin Co-polymer
Poly Alkyl Styrene
HSDC Styrene Butadiene Co-polymer
Styrene – Isoprene Co-polymer
ESTER TYPE
PMP [Poly Alkyl Acrylate
Styrene Maleic Acid Copolymer]

28. USES OF VI IMPROVERS PMA 21%, HSDC 17%, OCP 67%
VI improver made possible the advent of multigrade oils e.g. SAE low 30 or SAE 15w40 for gasoline engine (67%) diesel engine (19%).

29. SELECTION DEPEND ON Requirement Other prop e.g. PPD, Dispersant
Shear Stability
Oxidation Thermal Stability

30. MECHANISM OF VISCOSITY MODIFICATION IN OIL
Oil associated with polymer
Polymer
LOW
Solubility
GOOD
Temperature
LOW
HIGH
Exist as random coil
Swollen by lube oil
Volume determine viscosity increase
At low temp. polymer remain as compact mass
At high temp. coil open up
Compensate fall in viscosity

31. USES OF VI IMPROVERS Automotive multi grade oils (engine, gear)
Gear and transmissions oils
Hydraulic fluids
Industrial oils
Dosage 2-6%

32. POUR POINT DEPRESSANTS
At low temperature wax crystalize out and prevent flow of oil
Dewaxing can reduce pour point
- Reduces yield
- Adversely effect VI
PPD – syn chemical which prevent congelation
PPD offer effective and economical alternative to dewaxing
PPD improve
- Low temperature fluidity
- Low temp performance
PPD mainly used in paraffinic oils

33. TYPES OF PP DEPRESSANTS
Non Polymeric
Polymeric
Recent Lit. indicate that majority of products are poly hydrocarbon HC-Ester co-polymer and ester co-polymer

34. MECHANISM OF ACTION (POUR POINT DEPPRESANT)
PPD don’t’ prevent crystallization
Change crystal habit
Probably by adsorption
Smaller crystals form
Do not interlock
Permit flow of oil

35. USES OF PP DEPRESSANTS Mono and multi grade Oil
Gear & Transmission oil
Hydraulic Fluid
Compressor Oil
Machinery Oil

36. LOAD CARRYING ADDITIVES (AW/EP)
Aw and EP additives are incorporated to extend oil’s load carrying capabilities
Important but less used
Inter metallic contact occur at asperities under boundary lubrication resulting heavy wear

37. TYPES OF ADDITIVES Additive are active compounds of S,Cl and P
S-Compounds
Dibenzyl disulfide
Butyl phenol disulfide
Sulfurised vegetable oils
Pb, Sb, Cd and Zn dithiocarbamates
Cl – Compounds
Chlorinated wax
Chlorinated fatty acids

38. TYPES OF ADDITIVES P - Compounds Tri cresyl phosphates ZDDP
Di-alkyl phosphates etc
P & S-Compounds
Zinc dialkyl dithio phosphates
Cl & S - Compounds
Chlorinated alkyl sulfide
Sulfurised chloronaphthalene

39. MECHANISM OF ACTION
Act by physical adsorption, chemisorption or chemical reaction with metal forming protective film
Film not penetrated by asparities
Prevent scoring and surface damage

40. USES OF AW/EP ADDITIVES
Engine oil
Gear and transmission oil
Shock absorber oil
Hydraulic oils

41. FRICTION MODIFIERS (FM)
During start-up and shut-down sliding surfaces subjected to high load (mixed friction range)
FM additives used, to prevent stick-slip oscillation, noise and reduce frictional force
To save energy, reduce fuel consumption (additives known as FM)
FM Similar to AW/ EP Additives

42. TYPES OF FRICTION MODIFIERS
FM are polar oil soluble materials
Only few gained commercial Acceptance
Mo-dithiophosphate and carbonate complexes
Dispersion of MoS2, graphite, PTFE
Ash less carboxylic acid esters, their oligomers and amines, amides

43. MECHANISM AND USES Mechanism By physical adsorption Uses Engine oil
Gear and transmission oil
Industrial oil
greases, etc.

44. ANTIFOAMING AGENTS
Requires where violent churning or agitation of oil occur
Effect of Foams on the Performance of Engine
Rise oil level,results in loss of oil
Oil feed pressure drops,
Insufficient oil supply

45. TYPES OF ADDITIVES POLYMERIC i) Poly organo siloxane CH3 CH3 CH3
Si O Si O Si O
ii) Poly acrylate
Iii) poly ethylene oxides
DOSAGE ppm n

46. MECHANISM OF ACTION Oil insoluble
Lower interfacial tension between air and oil
Permitting easy aggregation of air
Reduce foam stability

47. USES ANTIFOAMING AGENTS
Engine oils (automotive, rail, marine)
Gear oils
Automotive transmission fluids
Industrial oils
Metal working oils

48. RUST AND CORROSION INHIBITORS
Rust and corrosion of metal parts undesirable
Leads to wear and break down

49. RUST INHIBIOTRS
RESULT OF CHEMICAL ATTACK OF WATER IN PRESENCE OF OXYGEN

50. TYPES OF RUST INHIBITORS
A large variety of compounds patented mostly three types:
a. Neutral b. Acidic c. Overbased
Most Popular are
High mil. Wt. Carboxylic acid (Succinic acid)
Sulphonic acid
Phosphoric acid and their salts
Compounds formed by neutralization of these acids with organic base (e.g. Amines)

51. MECHANISM OF ACTION Physical Means
Work by forming strongly absorbed hydrophobic film

52. CORROSION INHIBITORS Corrosion occur due to attack of acid
Arising from
A) oil oxidation (org>)
B) blow-by of combustion products
(SO2 inorg)
Later sever in diesel engine

53. ADDITIVE TYPES Metal dialkyl dithio phosphates,
Phospho sulphurized olefins, terpenes
Org Phosphites,
Dithio carbamate
Most popular are basic detergent / dispersant additive

54. MECHANISM OF ACTION Forming absorbed protective films
By neutralizing acid materials
Also acts as Antioixdants, load-carrying additives

55. MISCELLANEOUS LUBE ADDITIVES
Anti-microbial agents used in cutting oil emulsions
Emulsifiers to manuf. Water based cutting oils
Odour masking agents
Dyes for identifications

56. MISCELLANEOUS ADDITIVES
Tackiness agents impart stickiness/ adherence property
(PIB, ethylene-propylene co-polymer)
Seal swalling agent to help swalling of rubber elastomers to required volume (phthalic acid ester, most popular di-octyl phthalate [DOP]

57. SOME GENERAL TYPE OF ADDITIVES USED IN A WIDE VARIETY OF LUBRICANTS
Seal Swell
Pour Point
Viscosity Improvers
Antifoam Agents
Extreme Pressure Agents
Friction Modifiers
Corrosion Inhibitors
Rust Inhibitors
Antiwear Agents
Antioxidant
Ashless Dispersant
Metallic Detergent
Metal Working Fluids
Turbine Oils
Gear Oils
Hydraulic Oils
Axle Oils
Automatic Trans. Fluid
Engine Oil
LUBRICANT TYPE
ADDITIVE