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5. On the contrary, Shri R. Nambirajan has cited technical literature in support of the respondent's claim. Bailey's Industrial Oil and Fat Products published by John Wiley & Sons at pages 735 and 736 states as follows : -
"Chemically the dehydration of castor oil involves removal of the hydroxyl ground and a hydrogen from an adjacent carbon atom in the ricinoleic acid portion of the triglyceride.
In the catalytic method, castor oil is heated under a vacuum at a temperature in the range of 230-280C in the presence of a catalyst until water is no longer evolved. Solubility characteristics change during dehydration. The starting castor oil is soluble in methanol and insoluble in petroleum ether; as dehydration progresses the product becomes insoluble in alcohol and soluble in hydrocarbon solvents. As the hydroxyl groups are removed viscosity decreases and iodine value and refractive index increase. Changes in these analytical values are used to monitor and control the extent of dehydration and polymerization. The maximum iodine value occurs at or near the point of minimum viscosity; further heating leads to polymerization with a consequent drop in iodine value."

9. (i) Castor oil itself is "A light-yellow to brownish viscous oil obtained from the seed beans of the castor plant, Ricinus communis. Besides "its original use as a purgative in medicine, castor oil is one of the used industrial vegetable oils."

(ii) When castor oil is chemically dehydrated by removal of hydroxyle groups its properties change as per the "Materials Handbook" by George S. Brady and Henry R. Clauser as well as per the Kirk Othmer's "Encyclopedia of Chemical Technology". Thus for example, according to both of them iodine value, acid value and saponification value change and so also viscosity and solubility, colour etc. etc. But what is even more important from our point of view is that it involves chemical modification according to Kirk Othmer which goes on to say:

Further Analyses of commercial dehydrated castor oil indicates that using sulphuric acid as the catalyst, about 30% of the linoleic acid double bonds are conjugated in the 9, 11position. (And sulfonated castor oil, also known as Turkey red oil represents one of the earliest chemical derivatives of castor oil);

And as per Baileys Industrial Oil and Fat Products Solubility characteristics change during dehydration. As dehydration progresses the product becomes insoluble in alcohol and soluble in hydrocarbon solvents. As the hydroxyl groups are removed, viscosity decreases and iodine value and refractive index increase. Changes in these analytical values are used to monitor and control the extent of dehydration and polymerization."