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12-Hydroxy Stearic Acid (12-HSA)

12 HSA is an off-white solid fatty acid used to manufacture lithium and calcium based lubricating greases. When reacted with an ester, 12 HSA provides a hard finish for the automotive and small appliance industries. 

Production Process:

12-Hydroxy Stearic Acid is a waxy hydroxyl fatty acid. The source for the production of 12-hydroxy stearic acid is castor oil which contains up to 85% ricinoleic acid in the form of triglycerides. To produce 12-HSA, castor oil is subjected to hydrogenation, and as a result of it, the ricinoleic acid gets saturated at the place of the double bond and transforms into 12- hydroxyl stearic acid. This process is carried out at room temperature under a pressure of 40 psi with alcohol as a solvent.

In the hydrogenation process, the castor oil transforms into a solid mass, hydrogenated castor oil (HCO). The HCO consists of saturated glycerides of 12 HSA (upto 80%), ricinoleic (2-4%), stearic with traces of palmitic (10-15%), and oleic with traces of linoleic (1-4%) acids.

12 HSA is isolated from HCO by saponifying the latter with a 20-25% NaOH solution, followed by decomposing the soaps obtained with hydrochloric acid.

Properties of hydrogenated castor oil and of 12 HSA isolated from it depend substantially on the quality of castor oil, conditions of its hydrogenation, saponification of hydrogenated castor oil, decomposition of soaps by hydrochloric acid, washing, drying and storage of commercial 12 HSA.


         12 HSA is used in grease manufacture, plastics lubrication and as a raw material for the synthesis of more complex chemicals. It is used as a high hydroxyl castor based wax, as a wax ingredient.

         12-HSA based greases have excellent heat tolerance like the sodium greases and the water resistance of calcium greases.

         The addition of 12 HSA enhances the overall performance with better texture, improved heat stability and improved dropping points.

         12 HSA soaps are used in mineral oil-based multipurpose greases making it possible for grease to fill the requirements of a variety of needs in the automotive and truck greases.

         In cosmetics: 12 HSA may be used for gelling liquid petroleum to produce brilliance. It may be incorporated into cold creams and vanishing creams to give a jelly-like feeling.

         In paints: 12-HSA is reacted with acrylic esters to produce hard, durable thermosetting polymers used in high-quality automotive, industrial appliance and metal decorative finishes.

         In rubbers: 12-HSA functions as an activator and internal lubricant for natural and synthetic rubbers.


Chemical, Physical Properties and Specifications:

CAS Number





White Colour Flakes

Acid Value

175 Min.

Iodine Value

3.5 Max.

Melting Point

75C Min.

Saponification Value


Hydroxyl Value

155 Min.

Colour Gardner (G)

5G Max.


0.5 % Max.