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Diallyldithiocarbamidohydrazine (Dalzin) as an analytical reagent determination of palladium and its separation from nickel, zinc and copper
ANALYTICA CHIMICA ACTA
DIALLYLDITHIOCARBAMIDOHYDRAZINE
531
( D A L Z I N ) AS
AN A N A L Y T I C A L R E A G E N T D E T E R M I N A T I O N OF P A L L A D I U M AND ITS S E P A R A T I O N FROM NICKEL, ZINC AND C O P P E R N. K. D U T T AND K. P. S E N S A R M A
Department o[ Chemistry, University College of Science, Calcutta (fndia) (Received J u n e i o t h , 196o)
Dalzin has been used for the determination and separation of a number of metals 1. Further investigation has shown that palladium can be quantitatively precipitated from hot solutions by Dalzin at pH 3.1--4.5, while most of the common ions and other platinum metals remain in solution. Copper, mercury and silver interfere, but the interference of copper can be eliminated by complexing with EDTA and precipitating palladium at a pH below 4.5. Nickel and zinc can be determined in the filtrate alter raising the pH as usual. EXPERIMENTAL
Chemicals used were all of A.R. quality. A palladium solution was prepared from palladium chloride (Johnson and Matthey) and standardized gravimetrically as palladium dimethylglyoxime, pH measurements were made with Philips pH meter.
Composition o/ palladium complex Palladium was precipitated at pH ca. 4 by the method given below and the precipitate was dried at io5 ~ to constant weight. A weighed quantity was decomposed with aqua regia and evaporated several times with concentrated hydrochloric acid and the residue was taken up with this acid and diluted to IOO ml. Palladium in the solution was determined by the dimethylglyoxime method. The complex was found to have the composition Pd(CsH12N4S2) H20 (Pd. calc. 3o.22%, found 29.93%).
Determination o/ palladium The palladium chloride solution (3o-6o mg Pd) was neutralised with ammonia and diluted to about Ioo ml and the pH was adjusted with a freshly prepared solution of citric acid. The solution was heated on a water-bath and 25 ml of a hot alcoholic I.o% solution of the reagent was added with constant stirring. The brick-red precipitate was allowed to settle and was filtered through a weighed sintered glass crucible. Filtrates were kept for pH determinations. The precipitate was washed with hot water and acetone, dried at lO5 ~ and weighed (Pd factor ~ o.3o22). The results are shown in Table I. Anal. Chim. Acta, 23 (196o) 531-533
532
N. K. DUTT, K. P. SEN SARMA TABLE I Weight of Pd compound g
Pd found g
Pd taken g
pH
0.0983 o.1177 o.1198 o.1998
0.02971 0.03557 0.o3620 0.06040
0.03024 o.o3629 0.03629 o.06049
2.2 2. 7 3.1 3.5
o.I594 o.1795 o.118o o.1775
0.04818 0.05425 0.03567 0.05364
0.04839 0-05444 0.03629 0.05444
4.0 4.5 4.8 5.1
Separation o/Pd-Ni and Pd-Zn A solution of p a l l a d i u m containing nickel or zinc was t r e a t e d as in t h e a b o v e procedure. Nickel or zinc was e s t i m a t e d in the filtrate with the s a m e r e a g e n t as p r e v i o u s l y described 1. The results are shown in T a b l e I I . TABLE II Pd compound g
Pd found g
Pd taken g
Ni found g
Ni taken g
o.o998 o.12Ol o.1396 o.1596
o.o3oo6 o.o3629 0.04219 0.04825
o.o3o24 o.o3629 o.o4234 o.o4839
0.07791 0.02922 0.05832 0.04335
0.07801 0.02925 0.05850 o.o4388
o.1795 o.1797 o.Iooi O.lOO3
o.o5425 0.05431 0.03026 o.o3o32
0.o5444 0.o5444 o.o3024 o.o3024
Z n found g
Z n taken
0.04158 0.02487 0.04168 0.06231
0.04175 0.02505 0.04175 0.06212
TABLE III Wt. of foreign ion mg
Wt. of Pd compound g
Pd found g
Pd taken g
Cu
50 ioo 5~ IOO 50 5~
o.1179 o.12oo o.1595 o.18o6 o.1398 o.1596
0.03562 o.o3626 0.04828 0.05458 0.04225 0.04828
0.03629 o.o3629 0.04839 0.05444 0.04234 o.o4839
IOO 20o ioo 200 ioo 20o
o.1795 O.lOO3 O.lOO3 O.lOO3 O.lOO4 O.lOO5
o.o5425 0.03o32 0.03032 0.03o32
0.05444 o.o3o24 0.03024 0.03024
0.03034
0.03035
0.03o37
0.03038
25 5~ 25 5~ 25 50
o.1795 o.1795 o.1794 o.18o 3 o.18o8 o.1792
0.05425 0.05425 0.05423 0.05446 0.05462
o.o5444 0.05444 o.o5444 0.05446 0.05444
o.o5416
0.05444
Be Mg C8 Ba Sr Th Ce Mn
Anal.
Chirn. Acta,
23 (196o) 531-533
DIALLYLDITHIOCARBAMIDOHYDRAZlNE AS REAGENT
533
Determination in presence o/ various ions Solutions of palladium containing other ions were treated as above. Copper was kept in solution with the aid of EDTA. The ions studied are given in Table I I I . SUMMARY P a l l a d i u m is p r e c i p i t a t e d q u a n t i t a t i v e l y b y D a l z i n a t pH ca. 4, a n d c a n be d e t e r m i n e d . I t is s e p a r a t e d f r o m nickel a n d zinc w h i c h c a n be d e t e r m i n e d in t h e filtrate w i t h t h e s a m e r e a g e n t . RI~SUMt~ L e s a u t e u r s o n t m i s a u p o i n t u n e m 6 t h o d e de dosage g r a v i m 6 t r i q u e d u p a l l a d i u m a u m o y e n de d i a l l y l d i t h i o c a r b a m i d o h y d r a z i n e ("Dalzine") ; il est possible d ' e f f e c t u e r u n e s 6 p a r a t i o n d ' a v e c Ni, Z n et Cu. ZUSAMMENFASSUNG 13eschreibung einer g r a v i m e t r i s c h e n B e s t i m m u n g y o n P a l l a d i u m m i t Hilfe y o n Diallyldithioc a r b a m i d o h y d r a z i n m i t A n g a b e n iiber T r e n n u n g e n y o n a n d e r e n Metallen. REFERENCE 1 N . K . ])UTT AND K . P . SEN SARM&, Anal. Chim. Acta, 15 (1956) 21, IO2.
Anal. Chim. dcta, 23 (t96o) 531-533
THE
GRAVIMETRIC DETERMINATION OF CADMIUM WITH SODIUM SALT OF 1-PHENYL-TETRAZOLINE-5-THIONE
THE
C A R L E. M O O R E AND T H O M A S A. R O B I N S O N
Loyola University, Chicago, Ill. (U.S.A.) (Received J u n e I9th, 196o)
The acid, i-phenyl-tetrazoline-5-thione, has the structure indicated in Fig. I. Structure I I has been proposed as the enolized form of structure I1, 2. Infrared absorption data, however, have shown that I is the preferred structure of the compound and t h a t the thiol form is not present 3. Investigations b y Lieber* and his associates have shown
N
C=S
~
N
C--SH
N--NH
N--
N
THIONE
THIOL
Ill
I
ii fl
II
Fig. I. i - P h e n y l - t e t r a z o l i n e - 5 - t h i o n e .
that the i-tetrazoline thionyl group is electron withdrawing and that the hydrogen residing on the nitrogen a t o m at position four of the heterocyclic ring is acidic. The * Our a t t e n t i o n w a s called to t h i s c o m p o u n d b y Professor E u g e n e Lieber of R o o s e v e l t U n i v e r s i t y .
Anal. Chim. Acta, 23 (196o) 533-537
DIALLYLDITHIOCARBAMIDOHYDRAZINE
531
( D A L Z I N ) AS
AN A N A L Y T I C A L R E A G E N T D E T E R M I N A T I O N OF P A L L A D I U M AND ITS S E P A R A T I O N FROM NICKEL, ZINC AND C O P P E R N. K. D U T T AND K. P. S E N S A R M A
Department o[ Chemistry, University College of Science, Calcutta (fndia) (Received J u n e i o t h , 196o)
Dalzin has been used for the determination and separation of a number of metals 1. Further investigation has shown that palladium can be quantitatively precipitated from hot solutions by Dalzin at pH 3.1--4.5, while most of the common ions and other platinum metals remain in solution. Copper, mercury and silver interfere, but the interference of copper can be eliminated by complexing with EDTA and precipitating palladium at a pH below 4.5. Nickel and zinc can be determined in the filtrate alter raising the pH as usual. EXPERIMENTAL
Chemicals used were all of A.R. quality. A palladium solution was prepared from palladium chloride (Johnson and Matthey) and standardized gravimetrically as palladium dimethylglyoxime, pH measurements were made with Philips pH meter.
Composition o/ palladium complex Palladium was precipitated at pH ca. 4 by the method given below and the precipitate was dried at io5 ~ to constant weight. A weighed quantity was decomposed with aqua regia and evaporated several times with concentrated hydrochloric acid and the residue was taken up with this acid and diluted to IOO ml. Palladium in the solution was determined by the dimethylglyoxime method. The complex was found to have the composition Pd(CsH12N4S2) H20 (Pd. calc. 3o.22%, found 29.93%).
Determination o/ palladium The palladium chloride solution (3o-6o mg Pd) was neutralised with ammonia and diluted to about Ioo ml and the pH was adjusted with a freshly prepared solution of citric acid. The solution was heated on a water-bath and 25 ml of a hot alcoholic I.o% solution of the reagent was added with constant stirring. The brick-red precipitate was allowed to settle and was filtered through a weighed sintered glass crucible. Filtrates were kept for pH determinations. The precipitate was washed with hot water and acetone, dried at lO5 ~ and weighed (Pd factor ~ o.3o22). The results are shown in Table I. Anal. Chim. Acta, 23 (196o) 531-533
532
N. K. DUTT, K. P. SEN SARMA TABLE I Weight of Pd compound g
Pd found g
Pd taken g
pH
0.0983 o.1177 o.1198 o.1998
0.02971 0.03557 0.o3620 0.06040
0.03024 o.o3629 0.03629 o.06049
2.2 2. 7 3.1 3.5
o.I594 o.1795 o.118o o.1775
0.04818 0.05425 0.03567 0.05364
0.04839 0-05444 0.03629 0.05444
4.0 4.5 4.8 5.1
Separation o/Pd-Ni and Pd-Zn A solution of p a l l a d i u m containing nickel or zinc was t r e a t e d as in t h e a b o v e procedure. Nickel or zinc was e s t i m a t e d in the filtrate with the s a m e r e a g e n t as p r e v i o u s l y described 1. The results are shown in T a b l e I I . TABLE II Pd compound g
Pd found g
Pd taken g
Ni found g
Ni taken g
o.o998 o.12Ol o.1396 o.1596
o.o3oo6 o.o3629 0.04219 0.04825
o.o3o24 o.o3629 o.o4234 o.o4839
0.07791 0.02922 0.05832 0.04335
0.07801 0.02925 0.05850 o.o4388
o.1795 o.1797 o.Iooi O.lOO3
o.o5425 0.05431 0.03026 o.o3o32
0.o5444 0.o5444 o.o3024 o.o3024
Z n found g
Z n taken
0.04158 0.02487 0.04168 0.06231
0.04175 0.02505 0.04175 0.06212
TABLE III Wt. of foreign ion mg
Wt. of Pd compound g
Pd found g
Pd taken g
Cu
50 ioo 5~ IOO 50 5~
o.1179 o.12oo o.1595 o.18o6 o.1398 o.1596
0.03562 o.o3626 0.04828 0.05458 0.04225 0.04828
0.03629 o.o3629 0.04839 0.05444 0.04234 o.o4839
IOO 20o ioo 200 ioo 20o
o.1795 O.lOO3 O.lOO3 O.lOO3 O.lOO4 O.lOO5
o.o5425 0.03o32 0.03032 0.03o32
0.05444 o.o3o24 0.03024 0.03024
0.03034
0.03035
0.03o37
0.03038
25 5~ 25 5~ 25 50
o.1795 o.1795 o.1794 o.18o 3 o.18o8 o.1792
0.05425 0.05425 0.05423 0.05446 0.05462
o.o5444 0.05444 o.o5444 0.05446 0.05444
o.o5416
0.05444
Be Mg C8 Ba Sr Th Ce Mn
Anal.
Chirn. Acta,
23 (196o) 531-533
DIALLYLDITHIOCARBAMIDOHYDRAZlNE AS REAGENT
533
Determination in presence o/ various ions Solutions of palladium containing other ions were treated as above. Copper was kept in solution with the aid of EDTA. The ions studied are given in Table I I I . SUMMARY P a l l a d i u m is p r e c i p i t a t e d q u a n t i t a t i v e l y b y D a l z i n a t pH ca. 4, a n d c a n be d e t e r m i n e d . I t is s e p a r a t e d f r o m nickel a n d zinc w h i c h c a n be d e t e r m i n e d in t h e filtrate w i t h t h e s a m e r e a g e n t . RI~SUMt~ L e s a u t e u r s o n t m i s a u p o i n t u n e m 6 t h o d e de dosage g r a v i m 6 t r i q u e d u p a l l a d i u m a u m o y e n de d i a l l y l d i t h i o c a r b a m i d o h y d r a z i n e ("Dalzine") ; il est possible d ' e f f e c t u e r u n e s 6 p a r a t i o n d ' a v e c Ni, Z n et Cu. ZUSAMMENFASSUNG 13eschreibung einer g r a v i m e t r i s c h e n B e s t i m m u n g y o n P a l l a d i u m m i t Hilfe y o n Diallyldithioc a r b a m i d o h y d r a z i n m i t A n g a b e n iiber T r e n n u n g e n y o n a n d e r e n Metallen. REFERENCE 1 N . K . ])UTT AND K . P . SEN SARM&, Anal. Chim. Acta, 15 (1956) 21, IO2.
Anal. Chim. dcta, 23 (t96o) 531-533
THE
GRAVIMETRIC DETERMINATION OF CADMIUM WITH SODIUM SALT OF 1-PHENYL-TETRAZOLINE-5-THIONE
THE
C A R L E. M O O R E AND T H O M A S A. R O B I N S O N
Loyola University, Chicago, Ill. (U.S.A.) (Received J u n e I9th, 196o)
The acid, i-phenyl-tetrazoline-5-thione, has the structure indicated in Fig. I. Structure I I has been proposed as the enolized form of structure I1, 2. Infrared absorption data, however, have shown that I is the preferred structure of the compound and t h a t the thiol form is not present 3. Investigations b y Lieber* and his associates have shown
N
C=S
~
N
C--SH
N--NH
N--
N
THIONE
THIOL
Ill
I
ii fl
II
Fig. I. i - P h e n y l - t e t r a z o l i n e - 5 - t h i o n e .
that the i-tetrazoline thionyl group is electron withdrawing and that the hydrogen residing on the nitrogen a t o m at position four of the heterocyclic ring is acidic. The * Our a t t e n t i o n w a s called to t h i s c o m p o u n d b y Professor E u g e n e Lieber of R o o s e v e l t U n i v e r s i t y .
Anal. Chim. Acta, 23 (196o) 533-537