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Vol. 21, No. 1
Still another field in which vanadium is commencing to While the research work is actually done by the Vanadium appear is that of chemotherapy. Various vanadium com- Corporation in an effort t o determine the alloy steel best pounds have been suggested in the literature for the past suited for car springs, it involves in this effort the active fifty years as being possible valuable drugs in combating cooperation of the railroad, which supplies cars for experivarious diseases. Only very recently, however, have such mentation; of the manufacturers of the car springs, who are drugs actually been adopted. They are as yet practically experimenting with their re-design; and of the steel manuunknown in the United States, but in France there have facturers, who supply the alloy steel used in the fabrication appeared several proprietary organic and inorganic com- of these springs. Such cooperation is the rule rather than the pounds of vanadium for the treatment of dyspepsia, grippe, exceptional case, and an excellent spirit between the indusanemia, and the early stages of tuberculosis. Three of these tries involved has been the general result. Any possible appear, respectively, under the following names: VANUCLEOLcriticism of the research as leaning in favor of vanadium is -Solute leucosthenique injectable; VmADARsIm-Solution obviated by the fact that the Vanadium Corporation, since titree d'arseniate de vanadium au centieme; and VAXADIKE- its merger in 1924 with the United States Ferro-Alloys ComD'oxide vanadique chloratee. It is also reported that pany, has been active in the general ferro-alloy field. vanadium salicylate is being experimented with as a subResearch as a Fundamental Industrial Necessity stitute for salvarsan in the treatment of syphilis. A new offshoot of the work of the research laboratory has An attempt has been made to show the manner in which been the preparation of a number of rare chemicals of c. P. research has entered vitally into all the phases of a particular and technical grades. Of these chemicals, one hundred and seventy have already been produced and are now available. industry. While the profit from this research has been They include inorganic and organic compounds of vanadium, evident in the growth of the Vanadium Corporation itself, molybdenum, tungsten, zirconium, chromium, titanium, it does not end there. Industry in general has profited colbalt, and uranium, and are, in general, not readily obtain- largely, if indirectly, by the results of work done in the research laboratory of this company. Industry in general able from other sources. may profit still further by emulating the example set by this Research as Consulting Service particular organization of using the research laboratory, properly manned and administered, as the agency which Inasmuch as the Vanadium Corporation does not sell its products directly as final materials to ultimate consumers, both creates and supplies demand. but rather as intermediate products to the manufacturers of Acknowledgment various commodities, the research work done on the utilization of vanadium has necessarily assumed in many cases the Thanks are due B. D. Saklatwalla, vice president of The character of a consulting service. A good example of this Vanadium Corporation of America, and director of the reis work now under way to improve the riding comfort of the search laboratory, for assistance in the preparation of this cars of one of the large railroad systems of the country. article.
Boiling Points of Electrolytic Caustic Solutions' C. C. Monrad and W. L. Badger UKIYERSITY OF MICHIGAN, AKNARBOR,~ I I C H .
N A previoue publication by one of the authors2the discrepancies in the existing information on the boiling points of electrolytic caustic solutions were indicated. Shortly after that paper was written, work was begun on a redetermination of boiling points of these solutions with the hope that data could be obtained of greater accuracy and over a wider range than heretofore. I n the interval Adams and Richards3 published the results of Pink, which confirmed fairly well some of the figures used by Badger in his article. Since caustic evaporators are now in operation with working temperature drops of less than 10" C., it is obvious that an accuracy of * 1' C. is no longer within the limits of commercial requirements. The method of prediction advocated by Adams and Richards involves errors of several degrees for solutions boiling under considerably diminished pressure. The present series of data are so much more complete and of so much greater precision than anything a t present in the literature that they will be presented in considerable detail.
I
Apparatus
Previous workers had used glass apparatus, which is open t o the objection that glass is rapidly attacked by strong caustic August 2, 1928. SBadger, Trans. Am. Inst. Chem. Eng., 18, 231 (1926). * I N D .ENQ. CHRM.,20 470 (1928). 1 Received
solutions. Pink not only used glass apparatus but immersed the thermometer directly in the solution to be examined. This causes errors due to superheating and possibly smaller errors due to hydrostatic head, The apparatus used in this investigation is a modification of that described by Baker and Waite4 and is illustrated in Figure 1. A is a boiling vessel made of monel with a suitab!e cover carrying a monel tube as a vapor pipe. Into the bottom of the bomb was inserted a closed monel tube, A , in the interior of which was inserted a chrome1 heating element wound on Usalite tubing. Over this heating element stood the modzed Cottrell pumping tube, C, made entirely of monel. The side outlet to the bomb used for withdrawing samples was also of monel. The vapor pipe was surrounded by an iron condenser, D, and contained the precision platinum resistance thermometer, E. The glass tube which formed the casing of this thermometer was first silvered and then nickel-plated so that the solutions came in contact only with monel or nickel. A short connection led directly from the vapor space to the barometermanometer combination, F , from which the absolute pressure could be read as the difference in the two mercury columns. From the vapor pipe another glass tube led t o the vacuumproducing and -regulating system. This consisted of a 12liter flask, H , for damping out fluctuations in the pressure, (r
Tans. Am.
Inst. Chem. Eng., 13, P t . 11, 233 (1921).
January, 1929
INDUSTRIAL AND ENGINEERING CHEMISTRY
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poffa and Sommer.' These two sets of determinations checked so closely that in the present work sodium chloride was not determined. From the known temperature and caustic concentration of the samples, the concentration of sodium chloride was calculated, and thus the ratio of sodium hydroxide to water was determined. For any one sample this is constant a t all temperatures, irrespective of the sodium chloride content. Table I-Thermometer
c.
0
O
for Determination of Boiling Points of Caustic Solutions
connected to a water trap, I , and this through N t o a laboratory water-jet vacuum pump. The trap I was connected to a manometer, M , on the high side of which was a platinumtipped brass rod, L. As the vacuum rose it made a contact between the mercury and this rod, closed a battery circuit through the relay K , which then closed the 220-volt circuit through solenoid J and opened the needle valve 0, admitting air to the system. By means of a stop which limited the travel of the needle valve to a fraction of a millimeter, it was possible to maintain the vacmm as shown by manometer -11 constant to within 1 or 2 mm., and these fluctuations were so removed by the flask H that the manometer F showed variations of the order of 0.2 mm. The Cottrell pumping tube kept the thermometer covered with a film of the boiling liquid in equilibrium with the vapor and prevented overheating a t this point. The
ance thermometer was calibrated against ice and steam, with the results shown in Table I. 11 The solutions were made up from caustic soda purified by alcohol and were saturated with so- $ dium chloride. An excess of solid sodium chlo- 5 O' ride was maintained in the boiling vessel a t all times, so that the solutions were saturated a t s their boiling points, as will always be the case in a the commercial caustic evaporators. Since the materials used were relatively pure, these solutions differ from commercial cell liquors by con-
c.
DIFFERENCE
c.
0.01 0.03 0.02 0.00
98.98 53.02 78.81 92.89
98.99 52.99 78.83 92.89
Figure I-Apparatus
Calibration
CALCULATED
ACTUAL
It m7as suspected a t first that a t different temperatures and different rates of boiling the amount of water draining back from the condenser D might not be uniform. For every solution used, samples were withdrawn a t three different pressures and their analyses were substantially identical. This proves that the amount of water in the vapor pipe and on the walls of the condenser did not vary enough t o affect the composition of the liquid. Accuracy of Results
It was not found possible to control the conditions during actual determinations closer than *0.05' C. The agreement of the analyses was so close that the errors could not account for any greater fluctuation in the boiling point than this figure. Further, the boiling point of each solution was determined a t a number of pressures, and in no case did these points deviate more than 0.1 ' C. from the best straight line that could be drawn through them. It is believed that the data here reported are accurate t o within *0.lo C. up to 50 parts caustic per 100 parts water, and to *0.2" C. above that concentration.
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J 115
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120
130
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