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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 ENGINEERIXG CHEMISTRY
THE HYDROCHLORIDE METHOD FOR THE DETERMINATION OF ALKALOIDS’ B y GEO. D. BEAL AND Sr.
ELMOBRADY
The present research was undertaken in t h e hope of securing a method for t h e precipitation of alkaloids which might be used as a combined gravimetric and volumetric analytical method, each end point serving as a check on t h e other. The method, in brief, consists in t h e extraction of t h e alkaloid with ether, precipitation from this solution as the hydrochloride by passing in dry, gaseous, hydrochloric acid, evaporating off the ether a n d weighing t h e salt, then dissolving the hydrochloride in water and titrating the hydrochloric acid with standard alkali, using phenolphthalein as indicator. The results obtained have been checked in each case by a standard method already in use, t h a t of t h e U. S. P. VI11 being used wherever available. The first sample used consisted of conium seeds from the grounds of the College of Pharmacy building in Scio, Ohio. These were ground to No. 60 powder and extracted with a mixture of ether, alcohol and ammonia. The extract was shaken out with .V/I sulfuric acid to free the alkaloid from coloring and fat. The acid solution, which contains t h e alkaloids: was made alkaline with ammonia and t h e freed alkaloids extracted with ether. The ether extract, colorless and free from fat, was saturated with gaseous hydrochloric acid, which had been dried by passing through concentrated sulfuric acid. On this treatment, t h e hydrochloride of t h e alkaloids separated, partly as a crystalline solid and partly as a n oil. When the ether was evaporated on t h e water bath crystalline coniine hydrochloride was left behind, which was weighed and the percentage of coniine calculated for the drug. The salt was then dissolved in water and the solution titrated with standard alkali t o t h e phenolphthalein end point, and t h e result calculated on t h e assumption t h a t t h e salt formed was t h e monohydrochloride. P E R CEKTCOKIINE Sample Ai Sample Az Sample A3 B y weight . . . . . . . . . . . . . . . . . . . 1 . 7 4 1.72 1.725 1.67 1.70 B y t i t r a t i o n . . . . . . . . . . . . . . . . . 1.67
To test the accuracy of t h e above results t h e seeds were then analyzed by t h e U.S. P. method, in which
1’01. 8, NO.
T
the ether extract is evaporated with an excess of aqueous hydrochloric acid and t h e dry salt weighed, with t h e additional step added t h a t this U. S. P. residue was dissolved and titrated as above described. PERCEKTCONIIXE Sample Bi By weight . . . . . . . . . . . . . . . . . . . 1 . 7 3 By t i t r a t i o n . , . . . . . . . . . . . . . . . I . 70
Sample Bz 1.72 1 . 705
Sample B3 1.74 1.69
Some redistilled coniine was dissolved in ether, precipitated, weighed and titrated as above described. GRAXSCONIINE Sample Ci Theoretical.. . . . . . . . . . . . . . . . . . . . . . 0.125 B y %wight... . . . . . . . . . . . . . . . . . . . . . 0.12525 By titration., . . . . . . . . . . . . . . . . . . . . . . .
Sample C2 0.030 0,03006 0.02887
Sample C2 was treated with silver nitrate in t h e presence of nitric acid a n d t h e silver chloride formed weighed and calculated for t h e monohydrochloride of coniine. GRAMSAgCl
Theory, 0 0084
Found, 0 0085
These last results serve t o confirm the nature of t h e precipitate obtained. Because of our success in this work we determined t o extend the field, and have applied t h e method t o t h e analysis of tobacco and colchicum root. The extraction followed was practically t h e same as in the case of the conium. I n each case the oil was observed, as well as t h e crystalline salt, on the addition of t h e gaseous HCl. PER CENTALKALOID COLCHICUM ROOT TOBACCO b y method Sample DI Sample Dz Sample E1 Sample E Gravimetric., , . . , . , 2 . 2 2 2.30 2.65 2.61 . . . . . . . . . 2.19 2.28 2.66 2.49 Standard (U. S.P , ) . . . . . . . . 2.25 2.28 (Kisslings ) 2 . 6 4 2.67
This work is being continued on other alkaloidal drugs, a n d in addition t h e nature of t h e insoluble oil is being investigated. From some recent work on t h e nature of some oils obtained with amines, it appears t h a t it is simply a higher hydrochloride, as some of t h e latter have been obtained carrying as many as ten molecules of HC1. If t h e oil be washed with cold ether until it is free from free HC1, it still fumes in moist air, and if it be placed in a vacuum desiccator with some stick potassium hydroxide, i t is converted t o t h e monohydrochloride, and t h e alkali becomes encrusted with potassium chloride. LABORATORY OF ORGANIC ANALYSIS UNIVERSITY OF ILLINOIS, URBANA
LABORATORY AND PLANT EXTRACTION AND RECOVERY OF RADIUM, URANIUM AND VANADIUM FROM CARNOTITE2 BY CHARLESL. PARSOXS, R . B. MOORE,S. C. LIXD, 0.C. SCHAEFER Received Dec. 15, 1915
The work of the Bureau of Mines on radium began in t h e fall of 1 9 1 2 . A preliminary report published in t h e summer of 19133 outlined t h e conditions of mining and t h e wastes involved in the carnotite ore 1 Presented at t h e 50th Meeting of t h e American Chemical Society. New Orleans, March 31 to April 3, 1915. Authors’ abstract from Bull. 104, U. S. Bureau of Mines. T h e bulletin contains complete detail descriptions of operations with full drawings both of floor plan and sections of t h e radium plant, as well a s half-tones of plant and apparatus. * Bull. 7 0 , Prel Rept., “Uranium, Radium and Vanadium,” b y R . B. Moore a n d K . L. Kithil.
region of t h e West. As a result oE this investigation, Dr. Ho-ward A. Kelly, of Baltimore, a n d Dr. James Douglas, of New York City, were interested, and they incorporated t h e National Radium Institute. This institute leased certain carnotite claims in Long Park, Col., with t h e right t o extract 1,000 tons of carnotite ore therefrom. The National Radium Institute arranged with the Bureau of Mines for a cooperative investigation of t h e methods of extracting radium from this ore and t h e saving of t h e wastes by the concentration Of the low-grade Ore formerly thrown on t h e dump. Sufficient funds were furnished t o be expended under t h e direction of t h e Director of t h e Bureau of
Jan., 1916
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
Mines, a n d t h e first plant was built in the spring of 1914, beginning production on a n experimental basis in June, 1914, T h e result of t h e preliminary investigation was so successful t h a t t h e institute authorized t h e construction of a second and larger plant which began operations in February, 191j ; t h e two plants have been run continuously since t h a t time. The object of the investigation was t o procure an adequate supply of radium for t h e treatment of cancer in t h e t w o hospitals connected with t h e Radium Institute a n d t o develop methods of extraction whereby the miners might obtain a more adequate return for their ore, which. before this investigation began, had been sold largely t o foreign manufacturers. Incidentally, methods have been developed for the preparation of sodium uranate, uranium oxide, and iron vanadate-by-products from t h e extraction of carnotite ore. Before t h e Bureau's opcrations began, several methods, t h e details of some of which have been kept secret, had been devised, for t h e extraction of radium from pitchblende and from carnotite.
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been employed in this country on carnotite ores but has the great disadvantage t h a t it carries a large part if not all of the silica into solution. This adds greatly t o the cost of operation and tends t o give radium-barium sulfates of a rather high degree of impurity which require special treatment. From the best accounts available, it appears t h a t this method docs not successfully extract more than i o per cent of the radium present in t h e ore. METHOD OF O R E T R E A T M E X T
T h e method devised by the Bureau of Mines is b a e d upon the fact t h a t strong, hot nitric or sulfuric acid dissolves radium-barium sulfates in considerable quantities, as well as t h e other soluble constituents of t h e ore. Hence t h e radium-barium sulfate left behind when dilute acids are used for leaching is obtained in solution and recovered. The use of strong, hot nitric acid, although it presented many difficult problems of chemical engineering. was chosen because thc radium-barium sulfate could be precipitated at once in a remarkably pure form and t h e nitric acid could be largely recovered in t h e form of sodium nitrate and used again. Accordingly a nitric acid plant was built in connection with the radium plant and has been regularly operating since February, 191s. I n t h e Bureau of Mines method, t h e ore, pulverized t o 2 0 mesh, is fed into an earthenware boiling kettle containing 38 per cent nitric acid. The nitric acid ( 1 2 1 Ibs. HNOI diluted to 38 per cent) is brought nearly to boiling b y means of steam passed through a glass tube. When t h e boiling point has been nearly reached the ore is added a shovelful at a time and t h e whole stirred, heating being continued. After the ore has all been added, heating is continued for I S minutes when t h e mass is run on t o F W I--K.\ulus PLAST K A T S O N I I . nAolr.niasrmorn an earthenware filter and t h e nitric These involved ( I ) the use of a n acid leach; ( 2 ) the acid separated from t h e ore b y suction. T h e ore use of a n alkaline leach followed b y acid; and ( 3 ) is re-treated with hot nitric acid of one-third the fusing t h e ore with some material t h a t would make original strength, and is then washed with hot water. extraction of t h e valuable contents possible. The This treatment brings into solution nearly all of acid leaches had been extensively used abroad and the uranium, about jo per cent of the vanadium, had shown a n extraction of not over i o per cent and and practically all of t h e radium present in t h e probably little over jo per cent of t h e radium content, carnotite, The residue is discarded. T h e filtered owing t o the f a c t t h a t t h e ores contain sulfates, and is stirred, and sodium hydroxide is run solution any radium sulfate present was n o t removed under in s l o ~ l y with the object of reaching as nearly as these conditions. The alkaline leach followed by a n acid leach would probably remove more radium possible the neutral point without forming a precipibut involves such grave difficulties of filtration t h a t it tate. I f too much sodium hydroxide is added, both seemingly has not been p u t into commercial use. iron and vanadium are precipitated, discoloring t h e Fusing the ore xvith sodium sulfate was long employed radium-barium sulfate. On the other hand. if not on pitchblende' and has been used in Australia b y enough sodium hydroxide is added, t h e acid remains Radcliffe in treating carnotite t h a t is obtained at too strong a n d the solvcnt action of the nitric acid Olary, South Australia. This carnotite, being mixed on the radium-barium sulfate is not sufficiently dewith ilmenite, is very different from the American creased. By a little practice t h e right point is easily carnotite. Fusion with sodium carbonate has also obtained. Barium chloride is then added in t h e proI Haifinger. Luding and uirich. B i r i r h l . sbrr die Btorbiilunp d n P d portion of 2 Ibs. of BaCI? t o I ton of ore and is thorblmd.RPckrldndr. K . K . A k o d . 1V;ssmrrhafI.. 111 (1908). 619.
T H E J 0 L ; R Y : I L O F I S D I . S T R I A L A S D I
