Lubricant Additives

Detergents 137

FIGURE 4.15 Synthesis of neutral and basic metal salicylates.

OH

COOK

R

OH

C

O M O

C

OH

R R

O O OH

C

O M O

C

OH

R R

O O

Potassium

alkylsalicylate

OH

COOH

R

Alkylsalicylic

acid

HCI

n MCO 3

·

Basic or overbased metal salicylate

M = Ca or Mg

+ KCI

Neutral metal salicylate

(soap)

Excess base

CO 2

Base

Stoichiometric

amount

Metal halide

FIGURE 4.16 Synthesis of neutral and basic phosphonates.

R

R

R

OH

P

R 1

R

OH

S

R

R

R 1

R

P

OH

O M O P

S S

HO

R

R

R

R 1

R

R

R

R

R 1

R

P

OH

O M O P

S S

HO

R

R

R

R 1

R

R

R

R

R

P O

R 1

O

M

R

S

Overbased or basic alkenylphosphonate

Base

Stoichiometric

amount

Polyisobutenylphosphonic

acid

X = O or S

or

R = H or alkyl

M = Ca, Ba

Divalent metal salt of

polyisobutenylphosphonic acid (soap)

Excess base CO 2

x MCO 3

·