June. 1927
INDCSTRIAL AND EN(YINEERIATG CHE'MISTR Y
aluminum, the bottom end having 51 holes in it. The weight of the brass plunger, consisting of a brass rod, a perforated brass disk a t the bottom, and a brass weight pan a t the top was 75 grams * 1 gram, and the weight of the aluminum plunger was 33 grams. Each plunger is prevented from striking the bottom of the cylinder by a tip 0.85 cm. long. The plunger therefore falls through 20 cm. of material. A bracket holds the upper end of the plunger rod so that it travels in a true line to the bottom, practically without friction. Method of Use
Temperature m u s t be taken into consideration just as with instruments for the measurement of viscosity. Provided the room temp e r a t u r e 1s approximately 20" C. (68" F.), the paint or other produ c t s u s e d will n o t change in temperature i n t h e short time req u i r e d t o m a k e the ~2 tests. It is therefore suggested that measurements be made a t this temperature. The cylinder is filled with material to the mark. The plunger to be used Figure I-Gardner-Parks Mobilometer is inserted and forced to the bottom. It is then raised to the point where the bottom end is flush with the upper surface of the paint. A weight is applied and the time in seconds for the plunger to fall to the bottom is determined with a stop-watch. When the tip a t the bottom of the plunger disk touches the bottom of the cylinder, an audible click may be heard. This procedure is repeated with a number of different weights and the points plotted on a curve.
*
produced with different grades of the same pigment ground in the same oil or with the same pigment ground in different grades of oils and varnishes. Tests of Reproducibility
Some doubt has been expressed as to the ability of a mechanic to reproduce the perforated disk plunger used in the mobilometer. It was thought that the openings in the apparatus would be very difficult to reproduce. I n this connection, however, some cooperative committee work is now being carried on by members of a subcommittee of Committee D-1 of the American Society for Testing Materials to determine the value of the mobilometer in various plants upon the same type of products. The mobilometers used in these cooperative tests were made by two different mechanics. Table I-Readings w i t h Gardner-Parks Mobilometer VISCOUSPRODUCTS PLASTIC PRODUCTS Seconds Seconds A Lubricating oil 1.4 Flat white paint 5 .i J Lubricating oil 5.4 Flat white paint 9.4 M Lubricating oil 6.6 Exterior gloss 21 Heavy cylinder oil 22 Exterior gloss 22
I n Table I are given a few readings obtained with the Gardner-Parks mobilometer when run with a brass plunger, a perforated brass disk attached and a weight pan, these having a combined weight of 74 grams. No additional load was applied to the weight pan. Constant temperature was maintained throughout. Table 11-Mobilorneter
LOAD
100%
CATSUP
GRAMS 100 150 200 300
T e s t s on Materials Other t h a n Paints a n d Varnishes Tomato Calsup 95% C A T S U P 90% C A T S U P 85% CATSUP 5% WATER
Seconds 35.0 17.2 11.0 6.0
10% W A T E R
Seconds
Seconds
14.8 7.8 6.0 4.2
9.0 5.3 4.2 2.5
15% W A T E R
Seronds 6.3 3.8 3.0
..
M a y o n n a i s e Dressing 100% MAYONNAISE 9570 5% MAYONNAISE OLIVE OIL
LOAD GRAMS
Seconds
Seconds 42.0 27.0 18.4 12.8 7.6
500 600 io0 800
Applications in Paint and Varnish Industry
1000
This apparatus has been found useful in controlling the consistency of dipping paints and japans, where evaporation of volatile constituents may cause the products t o increase in consistency so that they become difficult to use. A hydrometer would not be satisfactory for such work as the thinning material might be of the same specific gravity as the coating product, and the addition of any quantity of such thinners would not change the density. The apparatus has also proved useful in gaging the consistency of spraying paints, such as those used on railroads, to determine if proper amounts of thinner have been added by the painters. It has also been found of interest in the linoleum industry to gage the consistency of printing paints, which are generally thinned with substantial quantities of volatile petroleum products. These paints, which are used on a printing machine, must be kept a t a definite body if satisfactory results are to be obtained. The apparatus has also been useful in gaging the apparent consistency of pigmented lacquers. Heretofore the method used for gaging the consistency of clear lacquers was to determine the number of seconds required for a steel ball to fall through a column of the product. Obviously such a method could not be applied to colored opaque lacquers. The apparatus has also been used in determining the consistency of and the possible relation of consistency to the flowing power of brushing enamels, which have been
725
LOAD
GRAMS
Coal T a r COALTAR
looso
29.0 18.0 13.4 9.4 6 8
85% 15% COAL BENZENE TAR
Seconds 500 0
8 6
(a)
Vaseline LOAD 60% VASELINE 55% VASELINE GRAXS 40% MINERAL OIL 45% MINERAL OIL Seconds Seconds 100 200 500
Seconds
86.0
...
16.6
21.0 7.9
5070 VASELIXE 50% MINERAL OIL Seconds 5.7 2.9 1.4
2.5 3.00 a In the case of 100 per cent coal tar a load of 500 grams would take 86.0 seconds, while with a load of zero the movement of the plunger would hardly be perceptible. In the next case where the coal tar is diluted with 15 per cent benzene a load of 500 grams would make the plunger drop at such a speed that one would not be able t o record the time accurately. It can be seen that a zero load takes less time than the 500-gram load on 100 per cent coal tar. Wherever zero load is referred to, it is the weight of the plunger, all other loads are additional grams added to the weight pan.
Applications in Other Industries
The writers have conducted a few experiments with the mobilometer to determine its possible usefulness in other industries. Tests have been made with tomato catsup, mayonnaise dressings, mustard, and similar food products, vaseline, mineral oils, coal tar, and glue and soap solutions. The latter two substances, however, were tested a t temperatures or concentrations a t which they would not gel. I n
ISDUSTRIAL All-D EXGIiVEERIiVG CHEMISTRY
726
the results obtained with some of the materials which are presented in Table 11, it will be noted that wherever a small amount of diluent is added to the original product the mobilometer usually showed an appreciable difference in the time of flow, thus indicating the sensitivity of this apparatus t o small differences in the consistency of the product experimented with. If pressure-flow curves are desired for a product, a number of different readings are made with different loads, taking care that the product remains a t a fairly constant temperature. Should it be desired to reproduce a certain consistency, a standard pressure or load
Vol. 19, No. 6
which is best suited for the product should be used and the time in seconds of the rate of flow of the product be noted. All these above products were run at 20” C. (68’ F.) * 1O C. To each load should be added the weight of the brass plunger, a perforated disk attached and a weight pan, which was 74 grams. The load, or pressure, denotes the amount of weight added to the brass plunger. These tables should give interesting information upon what weights should be used for various products-that is, what weight will show the greatest difference in time of flow and be applicable to a wide range of consistencies.
Heat and Moisture as Factors in the Destruction of Gossypol in Cottonseed Products‘ By Willis D. Gallup DEPARTMENT OF AGRICULTURAL CHEMICAL RESBARCH, OKLAHOMA EXPERIMENT STATION, STILLWATER, OKLA.
Cotton seeds contain a toxic substance called gossyOR s o m e t i m e t h e Since this might come about pol, the destruction of which appears justifiable espemanufacturers of cotin a variety of ways it was cially if the seeds are to beusedasa cattlefood. Astudy thought well to mention some tonseed oil have known was therefore made of the effects of heat and moisture of the properties of this subthat during the expression of in bringing about the destruction of this substance stance. the oil from the cotton seeds within the seeds. there is removed, along with Properties of Gossypol Cotton seeds were heated dry in an electric oven, the oil and other impurities, heated in the presence of excess moisture (autoclaved), Gossypol occurs as a colorcertain substances which imand germinated. The time of the first two treatments ing matter in the internal part to the oil a dark redwas varied between wide limits and the decrease in glands of the cottonseed kerdish color. One of these subgossypol determined by chemical and biological methnels, and probably throughstances has recently aroused ods. out the cotton plant. It is considerable interest in view Heating the seeds in a dry condition effected achange quite insoluble in petrolic of its toxic properties, which in the form of the gossypol but only slowly reduced ether, but soluble in diethyl have been demonstrated by their toxicity. Heating the moist seeds in the autoe t h e r , chloroform. carbon Withers and Carruth2 in an clave rapidly destroyed the gossypol and produced a t e t r a c h l o r i d e , ethylene dieffort to explain the toxicity non-toxic product. Germination was not effective in chloride, acetone, and carbon of cottonseed meal. Marchreducing the toxicity of the seeds. disulfide. The amount found lewski3 had previously isoin “hull-free” kernel< by esl a t e d the same compound from the “foots” of Eottonseed oil and gave it the name traction with diethyl ether \-aries from 0.4 to 1.2 per cent. “gossypol.” Following the work of Carruth there was much According to Carruth6 its molecular weight is about 532, i t discussion in the literature as to the real cause of the dele- is very unstable in alkaline solution, and decomposes a t about terious effects produced in animals by feeding large quan- 176” C. to a dark mass. It combines with aniline and some tities of Cottonseed meal, and Schwartse and Alsberg4 quite other compounds with the - S H 2 grouping to form a less definitely established a relationship between the toxicity of soluble compound, and Carruth used this property as a means of its quantitative determination. cotton seeds and their gossypol content. Gossypol is readily oxidized in alkaline solution by hydrogen Since the meal consists of cottonseed kernels which have gone through a heating and pressing process to remove the peroxide and other oxidizing agents and its solution in organic larger portion of the oil, these investigators offer indirect solvents turns greenish black on the addition of iron salts. evidence as to the cause of the toxicity of the cottonseed I t may be isolated easily from cotton seeds by first removing meal. However, there is still considerable question as t o the oil with petrolic ether followed by extraction with dithe toxicity of the cottonseed meal as determined by its ethyl ether, which removes the gossypol and considerable gossypol content, since we know that the process of manu- coloring matter. After evaporating the ether completely facture has a very definite effect upon the gossypol which a t a low temperature, the gossypol is liberated by adding was contained in the original seeds, and Sherwood5 has petrolic ether. The purification of this product is best shown that not only is the amount lowered but it is possibly effected by dissolving it in a mixture of ether and 80 per cent changed in form. The present problem involves the elimi- acetic acid and allowing it to stand for several days. The nation of gossypol so that it no longer remains in the press gossypol crystallizes out in combination with acetic acid, cake to impair its feeding value after the oil has been removed. from which it is liberated by dissolving in ether and washing several times with water. The water removes the acetic 1 Received February 4 , 1927. Published with the permission of the acid and the free gossypol is recovered on evaporation of Director of the Oklahoma Experiment Station, C. T. Dowell, who initiated the study of factors in0uencing the gossypol content of cottonseed meal in the ether. Schwartze and Alsberg7 found gossypol purified this laboratory. in a similar manner, when fed to experimental animals, J . Agu. Reseauch, 5, 261 (1915). t o produce “nearly all the manifestations reported as chara J . g r a k f . Chem., 60, 84 (1899). J Am. Chem. S o c , 40, 647 (1918). J . Agr. Research, 2 8 , l i 3 (1924).
F
2
4
5
6
I b i d . , 32, 793 (1926).
7
J . .-1gv. Resenrch, 28, 191 (1924).
