Oleochemicals

 

(from Latin: oleum “olive oil”) are chemicals derived from plant and animal fats. They are analogous to petrochemicals derived from petroleum.

The formation of basic oleochemical substances like fatty acids, fatty acid methyl esters (FAME), fatty alcohols, fatty amines and glycerols are by various chemical and enzymatic reactions. Intermediate chemical substances produced from these basic oleochemical substances include alcohol ethoxylates, alcohol sulfates, alcohol ether sulfates, quaternary ammonium salts, monoacylglycerols (MAG), diacylglycerols (DAG), structured triacylglycerols(TAG), sugar esters, and other oleochemical products.

As the price of crude oil rose in the late 1970s, manufacturers switched from petrochemicals to oleochemicals because plant-based lauric oils processed from palm kernel oil were cheaper. Since then, palm kernel oil is predominantly used in the production of laundry detergent and personal care items like toothpaste, soap bars, shower cream and shampoo. The largest application for oleochemicals, about 30% of market share for fatty acids and 55% for fatty alcohols, is for making soaps and detergents. Lauric acid, used to produce sodium lauryl sulfate and related compounds, which are used to make soaps and other personal care products. Other applications of oleochemicals include the production of lubricants, solvents, biodiesel and bioplastics. Due to the use of methyl esters in biodiesel production, they represent the fastest growing sub-sector of oleochemical production in recent years.

PALM OIL – BASED

TALLOW – BASED

SOYBEAN OIL – BASED

COCONUT OIL – BASED

Oleochemicals are important raw material for polymeric resins specially alkyd based because of possible functional group modifications. These modifications are based on reaction of vegetable oil with excess glycerol to obtain monoglyceride, which is then converted into polymeric resins i.e. alkyd by reacting with dicarboxylic acids or anhydrides. Recently polyesteramide resins are also prepared using vegetable oil as an oleochemical. Important processes in oleochemical manufacturing include hydrolosis and transesterification, among others.

Hydrolysis; The splitting (or hydrolysis) of the triglycerides produces fatty acids and glycerol: RCO2CH2–CHO2CR–CH2O2CR + 3 H2O → 3 RCOOH + HOCH2–CHOH–CH2OH. The addition of base helps the reaction proceed more quickly, the process being saponification.

Transesterification; Fats react with alcohols (R’OH) instead of with water in hydrolysis) in a process called transesterification. Glycerol is produced together with the fatty acid esters. Most typically, the reaction entails the use of methanol (MeOH) to give fatty acid methyl esters: RCO2CH2–CHO2CR–CH2O2CR + 3 MeOH → 3 RCO2Me + HOCH2–CHOH–CH2OH. FAMEs are less viscous than the precursor fats and can be purified to give the individual fatty acid esters, e.g. methyl oleate vs methyl palmitate.

Hydrogenation; The fatty acid or fatty esters produced by these methods may be transformed. For example, hydrogenation converts unsaturated fatty acids into saturated fatty acids. The acids or esters can also be reduced to the fatty alcohols. For some applications, fatty acids are converted to fatty nitriles. Hydrogenated of these nitriles gives fatty amines, which have a variety of applications.