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T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y .
ful services of Mr. W. G. Taggart, assistant chemist, in carrying out under my direction some preliminary ,experiments in this problem, leading u p t o those here reported. PRE9ENT ADDRESS OF THE AUTHOR, OF CHEMISTRY. BUREAU WASHINGTON, D. C.
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COCONUT OIL OF HIGH IODINE VALUE. By W. D . RICHARDSON.
Received July 3, 1911.
Recently several shipments of alleged coconut oil were received b y a large concern, and these shipments when analyzed gave iodine values of 18, 2 0 , 24 and 2 1 respectively. A little later another shipment of alleged coconut oil was received b y the same concern from another manufacturer, and this oil showed a n iodine value of 20. One of the principal chemical characteristics of the ordinary coconut oil of commerce, pressed from copra, is its low iodine absorption, the iodine number in a large number of instances being very close t o 8 per cent. When, therefore, the high iodine values were found, in the cases of the shipments referred to, a n investigation was started, which resulted in finding the cause of the high iodine values. I t was found t h a t the oil in question came from two manufacturers, both located in the United States. Both of these manufacturers, upon being questioned, stated t h a t their oil was pure coconut oil and t h a t nothing but coconuts were used in its preparation. Upon being questioned further they both admitted t h a t their oil was not pressed entirely from copra, b u t t h a t considerable proportions of the waste material from desiccated coconut factories entered their presses. They stated t h a t they used no unusual methods ' o r extreme temperatures in the preparation of their oil and they failed t o understand the reason for their oil showing different constants from the ordinary oil of commerce. The waste material from the desiccated coconut factories consisted of parings of the rind from the coconut meats, and when this fact was ascertained i t was thought best t o procure some fresh coconuts and extract the oil from the meats and from the rind, in order t o determine whether or not any difference in the oils from the two tissues existed. Accordingly a dozen coconuts were purchased, opened and the rind pared off from the meats. Both lots of the material were then dried separately a t low temperatures and the oil extracted b y means of ether. The following results were obtained: Iodine number. Per cent. Titer C. 23.3 Oil extracted from the meats of coconuts.. . 8.90 40.25 25.5 Oil extracted from the rind.. . , . . . . . . . . . . . ,
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The other constants, such as saponification number, were found t o be identical with those obtained in the case of the ordinary coconut oil of commerce. The titer, a s shown b y the above figures, is slightly higher in the case of the coconut oil from the rind. These figures plainly indicate a considerable difference in composition between the oil from the rind of the
Aug., 191I
coconut meats and from the meats themselves. The rind is such a small percentage of the whole kernel that in all probability the oil derived from this source does not affect t o any considerable extent the ordinary oil pressed from copra. On the other hand, when considerable quantities of parings are pressed, either separately or mixed with copra, the iodine value of the resulting oil is considerably increased. These results are of importance inasmuch a s the oils which would be most likely t o be used for adulterating coconut oil, would have the same effect upon the ordinary coconut oil of commerce, as does the coconut oil from the rinds. The present case appears t o be another instance of the well-known phenomenon of vegetable physiology, t h a t adjacent tissues in plants may contain oils of very different composition-a fact which is well exemplified in the case of palm oil and palm kernel oil. The above results indicate t h a t a coconut oil of relatively high iodine value is not necessarily adulterated b y a foreign oil, although i t can hardly be known as " coconut oil " in the ordinary commercial sense of the term, inasmuch as coconut oil has long been understood in commerce t o mean a n oil pressed from copra, that is, the whole dried coconut meat. It was thought t h a t the above facts were of sufficient interest t o the oil and fat industries t o warrant publication. LABORATORY OF SWIFT& COMPANY. CHICAGO.
DETERMINATION OF VANADIUM IN STEEL AND IRON. By B . 0 . CRITES.
Received June 7 , 1911.
The determination of vanadium in steel carrying this element in amounts varying from 0.05 per cent. t o 0 . 7 5 per cent. has been a problem commanding the attention of many of iron and steel chemists for several years. The methods given in the earlier editions of books on iron and steel analysis have been found almost wholly impracticable and those appearing in the more recent literature have neglected to give any very comprehensive idea of their accuracy or limits of accuracy. Realizing the difficulties involved in the estimation of rather minute quantities of vanadium in presence of large amounts of iron, it is not the intention of the writer t o severely criticize the work of other chemists in their efforts to produce satisfactory methods, but it seems t h a t a discussion of the subject might be of interest a t least t o chemists who have had only limited experience with this determination. A method said t o have been used by J. Kent Smith in his extensive work on vanadium was first tried b y the writer, the method in brief which was as follows: Four grams of steel were dissolved in sulphuric and nitric acids, the tungsten being separated b y the usual methods if present. The nitric acid was expelled b y evaporation t o the appearance of sulphuric acid fumes, then after dissolving the salts in water, chro-
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