laboratory and plant - American Chemical Society

in each case by a standard method already in use, that of the U. S. P. VI11 being used wherever available. The first ... To test the accuracy of the a...
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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 C E K TCOKIINE 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. P E R C E N TALKALOID 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