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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
the removal of nickel by roasting the tails from the copper flotation separation free from sulfur, reducing with charcoal, roasting with niter cake, and extracting with water, the nickel t o be recovered electrolytically or by precipitation with lime after th’e removal of iron by means of calcium carbonate. The complexity of this treatment would be a n important factor in determining whether the process could be used. The Alaska ore might be treated with nitric acid, heated t o remove most of the oxides of nitrogen, and the nickel extracted with water, the nitric acid being r‘ecovered by water absorption. The quantity of nitric acid recovered on large runs would largely determine the availability of this treatment. ACXNO WLEDGMENT
I wish t o thank Dr. R. B. Moore, of the Rocky Mountain Station, under whose direction this work was carried out, and t o express my appreciation of the many helpful suggestions received from other members of the Rocky Mountain Station of the United States Bureau of Mines a t Golden, Colorado. I also desire t o gratefully acknowledge the assistance rendered by Mr. M. H. Caron, of the Netherlands Government, who was so kind as t o reduce a quantity of t h e North Carolina ore in his experimental reduction furnace. BUREAUOB MINES GOLDEN,COLORADO
THE MODIFICATION OF THE COMPOSITION OF VEGETABLE OILS, WITH SPECIAL REFERENCE TO INCREASING UNSATURATION‘ B y HORACE L. WHITE Received January 1 7 , 1918 INTRODUCTION
The possibility of the modification of the constants of fats and oils of animal and vegetable origin, but more particularly because of the abundance of those of vegetable origin, is a matter of great economic importance. If a vegetable oil could be dehydrogenated, t h a t is, if its fatty acids could be modified so as t o contain more unsaturated linkages, there is the possibility of greatly increasing its value in the paint industry. A brief consideration of the respective iodine values of linseed and soy bean oils will indicate this more clearly. Linseed oil with a n iodine number around 180 is one of the best examples of a drying oil, while soy bean oil with a n iodine number around 126 is classified as a Nemzek3*has pointed out the limited semidrying oil. uses of soy bean oil in paints and he is authority for the statement t h a t in 1 9 1 6 there were imported into the United States 98,171,275 lbs. of soy bean oil. If some of the constants of this oil could be modified, its value, particularly in the paint industry, would be greatly increased. Many observers have pointed out the modifications of oils t h a t seem t o take place spontaneously, but which in reality are caused by t h e influence of light, temperature, bacterial and enzyme action, and inorganic 1 Abstract of a thesis submitted t o the University of Wisconsin for the degree of doctor of philosophy in agricultural chemistry, 1917. Numbers refer t o corresponding numbers in “Bibliography,” p. 651.
*
Vol.
11,
No. 7
catalysts. This investigation is devoted to a study of the biochemical., reactions induced by the processes of germination, and of enzyme and bacterial action on the degree of unsaturation and the extent of hydrolysis of linseed and SOY bean oils. I n addition, attention has been directed t o the action of light, heat, and the presence of inorganic catalysts on the same constants. EXPERIMENTAL
From reference in the literature it is evident t h a t but few attempts have been made t o dehydrogenate oils. The use of nickel6 in the absence of hydrogen has been suggested. I n the field of biochemistry t h e observations of Hartley and others6]’ on the desaturating power of the pig’s liver, as shown in t h e f a t t y acids obtained from the liver, is of great interest. The r e s ~ l t s ~obtained ,~ in a study of the effects of germination of various oil-bearing seeds seems t o indicate a saturation of unsaturated fatty acids during the process, yet the behavior of the castor beanx0in this particular shows some variation. The question was raised as t o whether there might not be conditions of metabolism during germination and growth of soy beans (Glycilze hispida) of such a nature as t o increase t h e degree of unsaturation of the f a t t y acids. The prevailing idea in the arrangement of the conditions of growth was t o make t h e m abnormal in order t o develop any latent powers of the plant. Theis was accomplished b y growing t h e plants in a greenhouse in diffuse light and a t lower temperatures t h a n ordinarily employed. Other samples were sprouted in darkness and some were grown in t h e sunlight a t ordinary temperatures. The germination was carried through three stages: Stage I, in which the sprout was cm. long; Stage 11, in which the plants were from 4 t o 6 cm. in height with cotyledons standing a t right angles t o the hypocotyls; and Stage 111, in which t h e plants were from 6 t o 1 2 cm. long and the first set of leaves had formed. TABLE I-CONSTANTSOF
SOY BEANSGERMXNATED AND GROWN DIFFUSELIGHT Stage I Stage I1 Stage I11 Resting Germinated Growth Growth Seed Sprout ‘/z Height Height Control Cm. Long 4 t o 6 Cm. 6 t o 12 Cm. 15.6800 37.0520 71.1560 .... 4.80 61.90 86.60 ....
THE OIL OF IN
..... ........ ............ ........ ............
Wt. 100 beans, grams Moisture, per c e n t . . ...... Ether extract (moisturefree), per c e n t . . 18.44 Color of o i l . . Amber 0.9234 Specific gravity.. Acid number. 1.0 Iodine number.. ......... 131.1 129.9 Iodine number.. 133.9 135.6 Fatty acids.. Reichert-Meissl number.. 0.30 Unsaponifiable matter, per cent .................. 1.21 0.27 Sterols, per c e n t . . 1 Red by reflected light, green b y
......... ............ ........
18.51 Green 0.9215 30.2 122.6 125: 5 125.2
...
13.31 Red Green’ 0.9272 2.6 133.1 133.0 136.2 133.6 1.05
1.14 1.01 0.43 0.46 transmitted light.
10.11 Greenish
....
12.5 121.10 120.95 117.7 116.1
....
2.75 0.86
The whole plant was used for analysis. Each plant was washed free from sand, dried a t 3 7 ’ C. in an incubator, and the oil extracted by ethyl ether in the cold, After distilling off most of the ether, the oil was heated t o 1 1 0 ’ C. for 2 hrs., while a current of dry carbon dioxide was bubbled through it t o remove traces of ether and water. The method of analysis and of purification of reagents used were those described by Holland.12 Iodine numbers were deter-
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
July, 1919
mined by the Hanus method. Table I shows some of the constants of the oils. The results given in Table I show t h a t t h e iodine number of the ether extract of soy beans grown in diffuse light does not fall much below t h a t obtained from the seed, and seem t o indicate t h a t while t h e oil is being used for the nourishment of t h e growing plant in diffuse light the processes of metabolism continue t o supply fatty acids of practically the same degree of unsaturation, a t least up t o the formation of the first set of leaves. The drop in iodine number of fatty acids in Stage I11 indicates a rapid utilization of unsaturated acids, possibly for t h e formation of sugars. For comparison, beans were planted in sand and grown in the light t o Stages I1 and 111. The results are shown in Table 11. TABLE II--cONSTANTS
OF SOY BEAN OIL FROM BEANS GROWNUNDER VARYINGCONDITIONS Ether Iodine Extract Number (Dry Basis) Acid Iodine Fatty DESCICIPTION Per cent Number Number Acids Resting seed 18.44 1.0 131.1 133.9 129.9 135.6 Stage I-Germinated seed., , 18.51 29.8 122.6 125.2
..................
.. . . ........ 13.31 Stage 11-Sunlight.. ........... 5 .OO Stage 111--Diffuse light.. ... , ... 10.11 . , ... 8 . 3 4 Stage 111--Darkness.. .. Stage 111--Sunlight. ........... 3.61 Stage 11-Diffuse
175
2.6 16.6 12.5
I , .
1
