The stearic acid manufacture comprises hydrolysis, hydrogenation and distillation processes. The hydrolysis process involves heating a fat in an alkaline solution such as sodium hydroxide (commonly known as caustic soda or lye). The result is the separation of fatty acids and glycerine, with stearic acid being one of the resulting components. The fatty acids can then be converted to saturated stearic acid by hydrogenation, which is typically performed with nickel in a continuous flow system. The hydrogenation process converts unsaturated fatty acids into stearic acid and other saturated fatty acids by the enzyme delta 9 desaturase.
The final step in the stearic acid manufacture is to refine the product into its pure form. The crystalline compound is used in a variety of industries, including soaps and detergents, polymers and cosmetics, as well as lubricants, antifoaming agents and bactericides. It can also be used to produce fatty acid salts and other organic compounds such as stearic esters, mono- or multi-alcohol ester surfactants and plasticizers.
The global stearic acid market is projected to grow at a rapid pace over the forecast period, with demand from the soaps and detergents industry driving growth. The growth in the personal care industry, particularly in Asia Pacific, is also expected to drive demand for stearic acid. In addition, a shift in trend toward bio-based surfactant usage is anticipated to boost the stearic acid market. This shift is likely to increase the use of stearates, such as sodium stearate and magnesium stearate, in products such as creams and lotions.