Hydrogenating cottonseed oil at relatively high pressure

Hydrogenation of triglyceride oils is obviously a complicated reaction involving not only several simultaneous and consecutive chemical steps but also
physical transfer steps of the reactants and products to and from the catalyst
surface. Factors of importance during hydrogenation include the following:
• Rate of hydrogenation expressed as the rate of decrease of the iodine value,
which is essentially directly proportional to the unsaturation.
• Hydrogenation selectivity defined as the preferential hydrogenation of polyunsaturated acid groups, such as linolenic and linoleic, relative to the monounsaturated groups, such as oleic acid.
•Isomerization. Cis-trans geometrical isomerization has been demonstrated (5)
to have a significant effect on the softening point and consistency of the fats.
In addition, positional isomerization also occurs in which the double bonds
migrate along the fatty acid chain (2, 3, TO, 77). The effect of this latter type
of isomerization on the physical properties of the pro