Question

What problems can occur if the iodine value of a starting material is too low? And too high ?

Answer 1

Iodine Value or Iodine Index : Is the mass of iodine that is consumed by the 100 gm of the substence. Iodine value or index is used to know the number of unsaturation sites in given fatty acid.

High Iodine value indicate more number of C=C and low Iodine value indicate less C=C.

When iodine value is very low it means the given fat is saturated and it is good for making soaps. And when Iodine value is high the fat is highly unsaturated and can be used as drying oil i.e. in paints.

Oil or fat with high Iodine value easily oxidised i.e. get rancidized and useless so with high Iodine value fats due care needed to be taken to preventing them from rancidizing.

oil with low Iodine value will not rancidie for long time and also get solidified at room temperature.

Lower Iodine value material tends to be present in soild form and high Iodine valu material tends to be in liquid form (oil form) at room temperature.