University of Southern California Dissertations and Theses

A critical study of the 8-hydro-oxyquinoline method for the determination of beryllium

(USC Thesis Other)

A critical study of the 8-hydro-oxyquinoline method for the determination of beryllium

PDF

Download

Open document

Flip pages

Download a page range

Download transcript

Copy asset link

Request this asset

Transcript (if available)

Content A CRITICAL STUDY OF THE 8-HYDROXYQUINOLINE M ETHOD
FOR THE DETERMINATION OF BERYLLIUM
A Thesis
Presented to
The F acu lty of the Department of Chemistry
U n iv e rsity of Southern C a lifo rn ia
In P a r t i a l F u lfillm e n t ! Degree not
lequirem ents for t]
Master of Science
,, ^ i g ran ted ; course
of the Requirements for the Degree work incomplete
by
Vito Warren Consoli
August 1941
UMI Number: EP41534
All rights reserved
INFORMATION TO ALL USERS
The quality of this reproduction is dependent upon the quality of the copy submitted.
In the unlikely event that the author did not send a complete manuscript
and there are missing pages, these will be noted. Also, if material had to be removed,
a note will indicate the deletion.
Dissertation Publishing
UMI EP41534
Published by ProQuest LLC (2014). Copyright in the Dissertation held by the Author.
Microform Edition © ProQuest LLC.
All rights reserved. This work is protected against
unauthorized copying under Title 17, United States Code
ProQuest LLC.
789 East Eisenhower Parkway
P.O. Box 1346
Ann Arbor, Ml 481 0 6- 1346
This thesis, written by
.......................... M .to....W .ai:x© n...G .Q X L 6Q li .
under the direction of h .A s Faculty Committee,
a n d 'a p p r o v e d by all its m e m b ers, has been
presented to and accepted by the Council on
Graduate Study and Research in partial fulfill -
m ent of the requirem ents fo r the d eg ree of
PIASTER OF ^SCIENCE
Secretary
.19.41
Faculty Com m ittee
Chairman
TABLE OF CONTENTS
CHAPTER PAGE
I . INTRODUCTION................................................. ' ........................... 1
I I . PROBLEMS STUDIED................................................................. . . 4
P resen t-d ay Procedure fo r the D eterm ination of
Beryllium in B eryl Ore by Means of the 8-
Hydroxyquinoline Method ................................................ 4
The Incomplete P r e c ip it a ti o n of Beryllium
Hydroxide Following Removal of Aluminum as
Oxyquinolate ............................................................................ 8
The Reagent, 8-Hydroxyquinoline . . . . . . * 10
A P ossible Modified Method for Determining
B eryllium a f t e r Removal of Aluminum as
Oxyquinolate ............................................................................ 15
I I I . EXPERIMENTAL W ORK ........................................... . 18
A Set of B eryllium D eterm inations Following
the Customary Procedure ............................................... 18
Data on the Modified Method fo r the
D eterm ination of Beryllium ........................................... 19
Data on the Attempted Laboratory P re p a ra tio n
of 8-Hydroxyquinoline ............................................23
IV. CONCLUSION................................................................................... 25
BIBLIOGRAPHY 28
CHAPTER I
INTRODUCTION
Sources and Uses of B eryllium .^
Beryllium is found, in the United S ta te s , in the Black
H ills of South Dakota p r in c ip a lly , and, o u tsid e of Maine and
New Hampshire, few o th e r spots in the country have produced
even a carload of the o res of th is elem ent. Most of the
domestic production i s obtained as a by-product of fe ld sp a r
and mica mining. This s it u a ti o n has c a lle d fo r con sid erab le
im p o rtatio n for the most p a rt from In d ia and A rgentina. The
only two companies in the country which o f f e r the metal and
i t s s a l t s on a commercial b asis a re the Beryllium C orporation
of Pennsylvania a t Temple, Pa., and the Brush Beryllium
C orporation of Cleveland, Ohio.
I t is most u n fo rtu n a te th a t the world output of
beryllium is no more than about 750 tons of b ery l per annum,
because i t s unusual p r o p e rtie s lend them selves to many v alu
ab le u se s. Great i n t e r e s t was shown in 1938 in the use of
the element in the v i t a l p a r ts of a irp la n e engines, due to
the g re a t hardness of over 1,000 B r in e ll which i s exhibited
in a s o lu tio n of b eryllium in gamma iro n .
1
M inerals Year Book. 748-751 (1936).
The p rice has always been so high for beryllium and
i t s a llo y s th a t i t has stood in the way of th e ir wider adop
tio n . There was, however, a drop of $7 per pound of con
tained b eryllium when i t went from $30 to $23 per pound in
the year 1937-8, and c u r re n tly i t is quoted a t $15 par pound
Pure beryllium has a nominal p ric e of from $75 to $125 per
pound, as th e re is p r a c t i c a l l y no market for i t .
H is to r ic a l Background of the A n a ly tic a l Chemistry
of Beryllium .
P o ssib ly no o th er element has been atta c k e d a n a l y t i -
g
c a l l y in so many d if f e r e n t ways as has beryllium , and t h i s
is e s p e c ia lly tru e of the vexing problem of se p a ratin g i t
from aluminum.
The method most fre q u e n tly used in e a r l i e r tim es was
founded upon the s o l u b i l i t y of beryllium hydroxide in am
monium carbonate. This idea, although i t was accepted a t
the tim e, r e s u l t s a lso in the p a r t i a l d iss o lv in g of the
2
hydroxides of aluminum and iro n . Vauquelin was the f i r s t
in v e s tig a to r to use the method in 1798. Since th a t time,
one method a f t e r another had been proposed only to be l a t e r
g
Parsons and Barnes, J . Amer. Chem. Soc.. 28. 1589
(1906).
^Vauquelin, Ann. Chim. Phys. . 2 6 . 155.
3
4
r e j e c t e d . Gibbs, in 1864, used the sodium f lu o rid e proced
ure to separate beryllium q u a n t ita tiv e l y , and t h i s method
5
received the approval of P ollok, who d ec lared i t to be
exceedingly sharp. This is a b r ie f o u tlin e of the a n a ly ti c a l
chem istry of beryllium from the time of Vauquelin to 1906.
£
At th a t time Parsons and Barnes proposed t h e i r sodium b i
carbonate se p a ra tio n of beryllium from aluminum, and t h i s
method has la ste d r i g h t through to th e p re s e n t day, and must
be included, along with the 8-hydroxyquinoline and Gooch and
Havens methods as one of the most im portant.
4Gibbs, Am. J. S c i . . (2 ), 37, 346.
^Pollok, T rans. Roy. Dublin Soc., ( 2 ), 139 (1904).
6Parsons and Barnes, lo c . c i t .
7Gooch and Havens, Am. J . S c i ., (4 ), j4, 111.
CHAPTER I I
PROBLEMS STUDIED
P resen t-d ay Procedure fo r the D eterm ination of
B eryllium in B eryl Ore by Means of the
8-Hydroxyquinoline Method.
Q Q
The method as recommended in the l i t e r a t u r e *3
f o llo w s :
0 .7 -0 .8 gram of the agate-ground ore is fused fo r 25
m inutes in a platinum c ru c ib le w ith 5 grams of sodium carbon
a t e . When p e r f e c t ly cool, the melt is tr a n s f e r r e d to a
400-ml beaker or evaporating d is h , tre a te d c a u tio u s ly w ith
h y d ro ch lo ric a c id , and is dehydrated follow ing the customary
procedure for the d eterraination of s i l i c a .
In order to recover any b ery lliu m which might have
been c a rrie d down in the s i l i c a dehydration, the s i l i c a is
ig n ite d in a platinum c r u c ib le , and tre a te d w ith h y d ro flu o ric
a c id . The oxides which remain behind in the c ru c ib le are
then fused w ith potassium b is u lf a te fo r about 25 m inutes,
dissolved in hydrochloric acid and the r e s u l t i n g so lu tio n
added to the o r ig in a l f i l t r a t e from which s i l i c a was removed.
8K o lth o ff and S an d ell, J . Amer. Chem. Soc. . 50. 1900
( 192 8).
9H. B. Knowles, J o u r. of R esearch. U. S. N a t 'l . Bureau
of Standards, 15,, 87 (1935).
The combined f i l t r a t e s w ill now contain a l l the beryllium
from the sample.
B eryllium , to g e th er w ith aluminum, iro n and o th e r 3rd
and 4th group elem ents, are freed from calcium and magnesium
by a sin g le p r e c i p i t a t i o n w ith ammonium hydroxide which is
added to the alm ost b o ilin g so lu tio n u n t i l a f a i n t but p e r
f e c t l y d i s t i n c t odor of ammonia p e r s i s t s . The p r e c i p i t a t e
of combined hydroxides is f i l t e r e d off and washed w ith Z%
ammonium c h lo rid e s o lu tio n , which has been rendered ju s t
a l k a li n e to litm us by the a d d itio n of ammonium hydroxide.
The hydroxide p r e c i p i t a t e s are disso lv ed w ith 25 ml
of h o t, 6N hy d ro ch lo ric a c id , the f i l t e r being w ell washed
afterw ard with hot w ater, and then the s o lu tio n is d ilu te d
to a volume of about 400 ml. 15 ml of ammonium a c e ta te
s o lu tio n (200 g r a m s / l i t e r ) , and 1 ml of bromcresol purple
in d ic a to r (0 .1 gram of the dye dissolved in 3.7 ml of 0.05 N
sodium hydroxide and d ilu te d to 250 ml) are added. The
liq u id is now tr e a te d w ith 6 N ammonium hydroxide u n t i l
d i s t i n c t l y purple and then, from a b u r e tte , a re added 50 ml
of 8-hydroxyquinoline s o lu tio n (made by t r i t u r a t i n g 10 grams
of the so lid w ith 23 ml of g la c ia l a c e t i c acid and then
d ilu t in g to 200 ml with d i s t i l l e d water a f t e r making sure
th a t a l l of the reag en t has gone in to s o lu t io n ) . The mixture
i s heated to b o ilin g and boiled g e n tly fo r a minute. I t is
then allowed to cool to 60°C whereupon the aluminum oxy-
6
q u in o la te is f i l t e r e d o ff and washed w ell w ith cold w ater.
The pure aluminum oxyquinolate is yellow but, in an ore
sample, w ill be more or le s s darkened, depending upon the
amount of iro n p re se n t.
The f i l t r a t e from the removal of aluminum i s now
tr e a te d with 6N ammonium hydroxide u n t i l the odor of ammonia
is c l e a r l y p e r c e p tib le , allowed to cool to room tem perature,
and the p r e c ip ita te d beryllium hydroxide i s f i l t e r e d o ff on
o p en -te x tu re a s h le s s f i l t e r paper. I t is washed w ith
ammonium a c e ta te s o lu tio n made ju s t a l k a li n e by the a d d itio n
of ammonium hydroxide. To make c e r t a i n of the t r a n s f e r of
every trace of beryllium hydroxide, the sid e s of the beaker
are rin s e d down w ith a l i t t l e h o t, 6N h y d ro ch lo ric a c id , and
the b eryllium i s r e p r e c ip ita te d in the bottom of the beaker
by a s l i g h t excess of d ilu t e ammonium hydroxide.
The beryllium hydroxide f i l t e r is tra n s f e r r e d to a
p o rc e la in c ru c ib le which has been weighed with i t s cover.
The paper is slow ly burned off w ith the c ru cib le uncovered.
Then the c ru c ib le i s covered w ith the cover in v e rte d and
heated a t the h ig h e st tem perature of the F ish er or Meker
burner fo r 45 m inutes, cooled in a d e s ic c a to r over f r e s h ly
concentrated s u lf u r ic acid o r, b e tte r y e t, "D ehydrite".
F urther heating in 15 minute sta g es i s continued u n t i l con
s ta n t weight is shown.
In s p ite of the rep o rted accuracy of the 8-hydroxy-
quinoline method, as shown by t e s t an a ly se s in the o r ig in a l
papers c ite d , the f a c t remains th a t r e s u l t s obtained by the
method in commercial la b o r a to r ie s are fa r from s a t i s f a c t o r y .
O ccasio n ally the r e s u l t s are a l i t t l e too high, but f r e
quently v alu es for b ery lliu m oxide are obtained which a re
fa r below the t r u t h . This suggests e ith e r r e t e n t i o n of
beryllium by the aluminum oxyquinolate, or incomplete p re
c i p i t a t i o n of beryllium hydroxide in the l a s t step of the
a n a l y s i s . Mention of p o s s ib ly incomplete p r e c i p i t a t i o n of
beryllium hydroxide is made by Knowles,^® who suggests th a t,
as a p re ca u tio n , i t is w ell to add a few drops of ammonia
s o lu tio n to the f i l t r a t e and allow i t to stand 24 h o u rs. In
t h i s way a few flo c k s of beryllium hydroxide are supposed to
be recovered. However, t h i s does not account for the lo ss
of as much as 20% of the t o t a l beryllium in a sample, and
lo s s e s of t h i s order have o fte n been found, acco rd in g to P.
H. M.-P. B rinton,*^ who fin d s the method u n re lia b le u n less
the f i l t r a t e from the beryllium hydroxide i s freed from
*
organic m atter by thorough o x id a tio n , a f t e r which the r e s t
of the beryllium can be p r e c ip ita te d by ammonium hydroxide.
Conventional treatm ent w ith s u lf u r ic and fuming n i t r i c ac id s
w ith p e rc h lo ric acid fo r o b s tin a te cases, was found to be
10H. B. Knowles, l o c . c i t .
■^P. H. M.-P. B rin to n , P riv a te Communication.
8
s u c c e s s fu l, though time-consuming. The d e t a i l s of the Oxi
datio n fo llo w :
The f i l t r a t e is evaporated to a volume of 50-75 ml and
rin sed in to a 300 ml K jeldahl f l a s k . 7 ml of concentrated
s u lf u r ic acid are added c a r e f u lly , followed by 2 ml of fuming
n i t r i c acid (Sp. Gr. 1 .5 0 ). The in c lin e d f la s k is heated
over a small flame u n t i l a volume of about 20 ml is a tta in e d ,
a t which po in t the so lu tio n is allowed to cool, and 2 ml more
of the fuming acid are added. This treatm en t should be r e
peated once or twice more. A c o lo rle s s s o lu tio n should then
be n o tic e a b le . I f n o t, the color can be discharged by adding
3 ml 60# p e rc h lo ric acid and co n tin u in g the h e a tin g .
The c o lo r le s s s o lu tio n , which may s o l i d i f y on cooling,
i s d ilu te d w ith w ater, tr a n s fe r re d to a beaker and f i l t e r e d
to remove tr a c e s of s i l i c a which w ill u s u a lly be found. The
c le a r f i l t r a t e is then tre a te d w ith a s l i g h t excess of am
monium hydroxide, and beryllium is determined as b efo re.
The amount found here is added to the f i r s t batch in c a lc u
la t i n g the percentage of beryllium oxide in the sample.
The Incomplete P r e c i p i t a t i o n of B eryllium Hydroxide
Following Removal of Aluminum as O xyquinolate.
In the f i l t r a t e , a f t e r removing the aluminum as oxy
q u in o la te , the in s tr u c tio n s for the d eterm in atio n of b e r y l l i
um p re s c rib e p r e c i p i t a t i o n as hydroxide by the a d d itio n of
9
ammonium hydroxide and then d e s tru c tio n of the organic m atter
whereupon more beryllium hydroxide w ill be recovered.
This phenomenon is never encountered when d ealin g with
s o lu tio n s of b eryllium c h lo rid e con tain in g no organic m atter,
the p r e c i p i t a t i o n of the hydroxide being a b s o lu te ly q u a n ti
t a t i v e . Furtherm ore, d i r e c t t e s t s have shown th a t when
e i t h e r the 8-hydroxyquinoline or the ammonium a c e ta te alone
i s p re se n t, incom pleteness of p r e c i p i t a t i o n i s n o t en
co untered. However, when both these re a g e n ts a re used,
according to the req u ired co n d itio n s fo r the aluminum-
beryllium se p a ra tio n , f a i l u r e to d e stro y the organic m atter
may r e s u l t in the lo ss of as h ig h as 2.0% of the t o t a l
beryllium content of the sam ple.1^
At the time of w ritin g of the a r t i c l e by H. B.
1
Knowles, ^ v ery l i t t l e a t t e n t i o n was paid to th is e rro r and
the author contented him self w ith the statem ent t h a t , in some
in s ta n c e s , the p r e c i p i t a t i o n of beryllium hydroxide might be
delayed and, for t h i s reason, i t was a d v isa b le to t r e a t the
f i n a l f i l t r a t e with a few drops of ammonia and perm it i t to
stand for 24 h o u rs. M. Frommes14 a ls o advised t h i s . As to
the cause of th is u n c e rta in ty in the 8-hydroxyquinoline
12P. H. M.-P. B rin to n , Loc. C it.
1
H . B. Knowles, Loc. C i t .
*4M. Frommes, Z e i t . fftr a n . Chemie, 9 3 . 287 (1933).
1 0
scheme, even today th ere is no concrete evidence.
The Reagent, 8-Hydroxyquinoline
S tru c tu re and S ynthesis of Oxine. The reagent,
8-hydroxyquinoline (a ls o known by the name 8-Q uinolinol
(Chemical A b s tr a c ts ) and, more p o p u larly , o xine) was f i r s t
prepared by Z . H. S k ra u p ^ follow ing the mode of sy n th e sis
which bears h is name. The reagent is derived from the p aren t
substance, q u in o lin e, by the s u b s t itu ti o n of an OH group in
the 8 -p o s itio n , according to the follow ing s e t of s tr u c t u r a l
form ulae: Hvo«oxY
N
OH
Oxine may th e re fo re be considered a h e te ro c y c lic
t e r t i a r y aminophenol or a hydroxy d e r iv a tiv e of the t e r t i a r y
h e te ro c y c lic amine, q u in o lin e.
The method of p re p a ra tio n of 8-hydroxyquinoline given
1 _ A
b y .B e ils te in c o n s is ts in dehydration of g ly c e ro l to form
a c r o le in through the a c tio n of co n cen trated s u l f u r i c acid ;
u Sft. CMC
c1* +
C H j . 0 H •»
_______________________
152I. H. Skraup, Wiener Monatsheft ftir Chemie, 3^,53®?
(1881). --------------------------------------------------
• ^ B e ils te in , et a l . , Handbuch der organischen Chemie.
4 th Ed., XXI. 91 (1935).
11
coupling of the a c r o l e in w ith the o-aminophenol;
and completion of the rin g clo su re by oxygen from the a rs e n ic
acid anhydride. _ ti
2-* Various Uses fo r t h i s R eagent. 8-Hydroxyquinoline
is a w hite, f l u f f y powder, which, when d isso lv ed in a so lv en t
such as g l a c i a l a c e tic acid , tu rn s to a deep orange shade.
The th e o ry upon which oxine is supposed to p r e c i p i t a t e
m etals is c a lle d the c h e la te - lin k a g e theory and involves the
follow ing conception. When a m e ta l lic ion r e a c ts w ith a
so lu tio n of 8-hydroxyquinoline, the hydrogen of the hydroxyl
group is replaced by m etal, the number of moles of oxine
required being determined by the valence of the m etal in
q u e s tio n . Now, due to the close proxim ity of the n itro g e n
to the hydroxyl group in the 8 -p o s itio n , th e re is thought to
e x i s t a fu rth e r e le c tro n ic a t t r a c t i o n of the n itr o g e n for
the m etal, causing a s u p e r f ic i a l bond between i t and the
m etal. Since t h i s bending-around of the n itro g e n to hold on
to the metal is in the shape of a c r a b 's claw, the name
"c h ela te" has been d e riv e d . The theory i s fu rth e r borne out
i a
w r*
12
by the f a c t th a t hydroxyl d e r iv a tiv e s of q uinoline w ith the
s u b s titu e n t in p o s itio n s other than the 8th do no t p r e c i p i
t a t e elements q u a n t ita tiv e l y . The follow ing s t r u c t u r a l
formulae are given to p ic tu re the c h e la te theory in the
r e a d e r ' s mind:
8-Hydroxyquinoline ranks as extrem ely im portant w ith
organic re a g e n ts which are used in inorganic a n a ly ti c a l
chem istry. There is probably no o th er compound of i t s type
th a t has been used to d e te c t and determ ine so many m etals as
oxine. P o ssib ly the f i r s t use fo r 8-hydroxyquinoline was
for the d eterm in atio n of magnesium in amounts under 1%*
This d eterm in atio n is c a rrie d out in s t r i c t l y a lk a lin e solu
tio n (pH g re a te r than 7 ) . Depending on the co n d itio n s of pH,
8-hydroxyquinoline has been put to use in determ ining alum i-
17
num, iron, calcium , and even barium. The work of Berg has
been undoubtedly the most v arie d in regard to the a p p lic a
b i l i t y of oxine as a p r e c i p ita n t for m e ta ls. Also n o te -
lft
worthy are the p u b lic a tio n s of Hahn.
17R. Berg, Z e it. ftlr an. Chemie, 71, 23, 171, 321,
369 (1927); 72, 177 (192777 76, 191 (19297; 81, 1 (1930).
18F. L. Hahn, et a l . , I b i d . . 71, 122, 225 (1927).
Oxine -g - Magnesium Magnesium Oxyquinolate
1 3
In the s e p a ra tio n of aluminum from beryllium , the
s o lu tio n must be d e f i n i t e l y on the acid side (pH about
4 .5 - 5 .0 ) , which is accomplished by the use of the ammonia-
ammonium a c e ta te b u ffe r p re se n t a t the time of s e p a ra tio n .
3. Procedure fo r Small L aboratory P re p aratio n of
8 - Hyd roxyquino1i n e . The c o st of 8 -hydroxyquinoline is r a th e r
high, about $2.90 per 100 grams; so, a l i t t l e thought was
given to the question of sm a ll-sc a le p re p a ra tio n of the
re a g e n t.
The mode of sy n th e sis followed in t h i s phase of the
work was a modified Skraup method, as given in an a r t i c l e
on stu d e n t p re p a ra tio n s of compounds in the h e te ro c y c lic
19
s e r i e s . ^
The re fere n c e followed in the p re p a ra tio n involved
a c t u a l l y two d if f e r e n t sy n th eses; F i r s t , the conversion of
o -n itro p h e n o l in to o-aminophenol and, second, the condensa
tio n of the l a t t e r with a c ro le in (from the g ly c e ro l) to form
the desired product, 8 -hydroxyquinoline.
In the f i r s t ste p , the o -n itro p h en o l is reduced to
the corresponding aminophenol by the a c tio n of a mixture of
sodium su lfid e-so d iu m hydroxide. Other methods of re d u c tio n
were, according to the a u th o rs, u n su c c e s sfu l.
^Wagner and Simons, J. Chem. Ed., JL3, 265 (1936).
14
The second step was c a rrie d out in a 500 ml round-
bottomed Pyrex f l a s k . The o-aminophenol, g ly c e r o l, s u lf u r ic
a c id , and a rse n ic acid anhydride were introduced, and the
mixture was g e n tly boiled f o r fiv e hours w ith a long r e f lu x
condenser. A fter allow ing the mixture to cool thoroughly,
i t was n e u tra liz e d , p r i n c i p a l l y w ith sodium hydroxide so lu
tio n , and f i n a l l y w ith sodium carbonate s o lu tio n u n t i l the
efferv escen ce ceased. The liq u id was then s te a m - d is t ille d ,
the water in the condenser being run out o c c a s io n a lly in
order to prevent the so lid 8 -hydroxyquinoline from clogging
the tube. The use of a Hopkins tr a p , although not mentioned
in the foregoing p u b lic a tio n , is a v ery good p re c a u tio n a ry
measure. The d i s t i l l a t e was cooled, f i l t e r e d on a Buchner
fu n n el, and the s o lid oxine washed w ith ice w ater. If the
product does no t melt w ith in a degree or two of i t s c o r re c t
m elting point (76°C), i t should be taken up in th e l e a s t
p o s s ib le amount of warm a lc o h o l, then p r e c i p ita t e d by pouring
t h i s so lu tio n in to a f a i r l y large volume of cold w ater. I t
was then cooled, f i l t e r e d o ff as before, and pressed out on
a porous p la te to d ry . The chem ical, when dry, should be
p ro tec ted from the a c tio n of l i g h t by being placed in a
brown b o ttle .
S t a b i l i t y of S o lu tio n s of 8 -Hydroxyquino1ine over
Considerable P erio d s of Time. Inasmuch as i t is n ecessary to
p r o te c t solid oxine from the a c tio n of li g h t by packaging i t
in brown b o ttle s , the doubt had always a r is e n whether i t was
a d v isab le to prepare la rg e q u a n t itie s of 8 -hydroxyquinoline
s o lu tio n in advance or to simply make a l i t t l e up in a c e tic
P C i
a c id as needed. K o lth o ff and Sandell s t a t e t h e i r p r e f e r
ence fo r an a c e tic a c id s o lu tio n of the reagent r a th e r than
an a lc o h o lic one, because the former "w ill keep fo r a week".
In order to s e t t l e t h i s im portant qu estio n once and
for a l l , Dr. B rin to n fu rn ish ed me w ith a badly d isc o lo red
sample of oxine s o lu tio n , which he had made up four y e a rs
ago by the conventional method of d is s o lv in g in a c e tic a c id .
This was used on 8 samples of the same beryl ore, which had
p re v io u sly been analyzed and whose composition was d e f i n i t e l y
known, and, in no in sta n c e was th e re any evidence to in d ic a te
th a t the aged so lu tio n had l o s t i t s s tr e n g th as a se p a ra tin g
agent for the aluminum from beryllium .
5. A P o ssib le Mod if ied Method for Determining B ery l
lium a f t e r Removal of Aluminum as O xyquinolate. Out of the
many attem p ts on the p a rt of the author to find an a l t e r n a t e ,
s h o rte r procedure by which to c a rry out the 8 -hydroxyquino
lin e s e p a ra tio n of aluminum from beryllium , the follow ing
method was developed:
pn
K olthoff and S andell, Loc. C i t .
16
F i r s t of a l l , much time and u n c e r ta in ty in the i n i t i a l
decom position of the ore was overcome by fo llo w in g Hun-
21
s a k e r 's method, u sin g sodium peroxide in a n ic k e l c r u c ib le .
This mode of decom position has two g re a t advantages. In the
f i r s t p la ce, decom position of the ore is made more c e r ta in by
the s u b s t itu ti o n of the stro n g er a l k a l i , sodium peroxide,
fo r the sodium carb o n ate, and the time of fusion is reduced
from 25 m inutes to le ss than 5 m inutes. Secondly, i t i s un
n ec essary to use the expensive and o fte n u n a v a ila b le platinum
wire for the fu s io n . When the peroxide method was employed
by Hunsaker, he was n o t follow ing the 8 -hydroxyquinoline
scheme but the Parsons and Barnes procedure, involving the
bicarbonate s e p a ra tio n . In the l a t t e r case, th e re was no
need for worry as to what e f f e c t the n ic k e l dissolved from
the c ru c ib le would have. In the oxine method, however, be
fore n ic k e l could be used, i t was n e c e ss a ry to c a rry out
c e r t a in experim ents to prove th a t there would be no n ic k e l
p re se n t in the f i l t r a t e for the d e term in atio n of beryllium
and which might e a s i l y be absorbed by the g e la tin o u s hydrox
id e . T herefore, a se t of ore samples was run using n ic k e l
for the decom position, and i t was noted th a t whatever n ic k e l
did n o t pass into the f i l t r a t e from the ammonia p r e c i p i t a
tio n , along w ith the calcium and magnesium, was com pletely
2 ^Hunsaker, '’Rapid Method for B e ry lliu m ," M aster's
T hesis, U n iv e rsity of Southern C a lifo rn ia , June, 1933.
1?
taken care of by the oxine reagent i t s e l f . This was e a s i l y
proved by d estro y in g a l l organic m atter in the f i n a l f i l t r a t e
and then t e s t i n g for n ic k e l by the u l t r a - s e n s i t i v e diraethyl-
glyoxime re a g e n t. In no instance was a tra c e of n ic k e l to
be found.
The second change in procedure which the au th o r found
to be r e l i a b l e was a m o d ificatio n of the manner in which the
organic m atter p re se n t in the beryllium f i l t r a t e was de
stro y e d . Instead of p r e c i p i t a t i n g the beryllium in two s te p s ,
and com pletely destro y in g the organic m atter by repeated
ev ap o ratio n s w ith small amounts of fuming n i t r i c a c id , the
whole f i l t r a t e (w ithout f i r s t p r e c i p i t a t i n g the bulk of
beryllium hydroxide) was tr e a te d w ith 30, ml of fuming n i t r i c
ac id and evaporated down to h a lf i t s o r ig in a l volume; i . e .,
from 600 to about 300 ml. The b eryllium may then be p r e c i p i
ta ted by the cau tio u s a d d itio n of ammonium hydroxide u n t i l
s l i g h t l y ammoniacal. A fter allow ing to stand fo r 20 m inutes,
i t is f i l t e r e d o f f .
The two foregoing procedures, then, c o n s titu te a
method which has seemed to the author to work out q u ite
s a t i s f a c t o r i l y and which re p re s e n t the saving of many hours
of te d io u s work.
CHAPTER I I I
EXPERIMENTAL W ORK
A large amount of p re lim in a ry experim ental work, a l l
the d e t a i l s of which need not be recorded, had in d ic a te d
th a t something about the combination of ammonium a c e ta te and
8 -hydroxyquinoline in te r f e r e d , in a very ir r e g u l a r way, w ith
the complete p r e c i p i t a t i o n of beryllium hydroxide. The ores
analyzed in each of the follow ing examples were of e x a c tly
the same com position;
A Set of Beryllium D eterm inations on Ore
Following the Customary Method.
Sample No. BeQ Content
1 .
2 .
3.
4.
12.15#
11.97#
12. 11#
12.21#
Average 12.12# BeO
R e su lts of N eglecting to D estroy Organic
M atter in the F in a l F i l t r a t e .
Sample No. BeO Content
1 .
2 .
3.
4.
5.
6 .
4.04#
5.81#
11.82#
9 .02#
6.83#
11.14#
m
E ffect of Reagents Involved on B eryllium
Chloride S o lu tio n .
Beryllium oxide was determined in 25 ml of each of
the follow ing beryllium c h lo rid e s o lu tio n s , w ith no regard
for the d e s tru c tio n of the organic m atter p rev io u s to the
p r e c i p i t a t i o n of beryllium h y d ro x id e :
1. 8 -H ydroquinoline Alone.
Volume of Oxine Used Weight of BeO/85 ml
0 ml 0.1036 gm. (Standard)
5 ml 0.1033 gm.
10 ml 0.1057 gm.
0 ml 0.0927 gm. (Standard)
5 ml 0.0922 gm.
10 ml 0.0925 gm.
0 ml 0.0304 gm. (Standard)
5 ml 0.0305 gm.
10 ml 0.0302 gm.
2. Ammonium A cetate Alone (2 0 ^ ).
Volume of A cetate Used Weight of BeO/25 ml
0 ml 0.0304 gm. (S tandard)
5 ml 0.0302 gm.
10 ml 0.0305 gm.
15 ml 0.0303 gm.
3. Ammonium A cetate Plus Oxine
2 0
15 ml A cetate Plus BeO/25 ml
________ Oxine_______ __________
10 ml 0.0676 gm.^
10 ml 0.0328 gm.
20 ml 0.0207 gm.
20 ml 0.0461 gm.
True S tre n g th of S o lu tio n 0.0556 gm.
/2 5 ml
U nsuccessful Modified Methods.
Quite a larg e number of m o d ific a tio n s were t r i e d in
order to t r y to overcome the extreme i r r e g u l a r i t i e s e v i
denced by the foregoing experim ents. A few of these w ill be
c ite d here along w ith the a n a l y t i c a l r e s u l t s obtained through
t h e i r use on b eryllium ch lo rid e s o lu tio n s , whose tru e con
c e n tr a tio n s had been p re v io u s ly determ ined.
1. Treatment w ith Bromine.
25 ml of b eryllium ch lo rid e so lu tio n had added to i t
10 ml of oxine so lu tio n p lu s 15 ml of a c e ta te s o lu tio n . 10
ml of bromine were then added, in the hope th a t the organic
m atter would be taken out as a bromo d e r iv a tiv e . A p r e c i p i
t a t e did form and, a f t e r standing fo r 1 0 m inutes, was
* I t is im possible to explain t h i s r e s u l t , but i t is
included in the i n t e r e s t of com pleteness.
21
f i l t e r e d off and w ell washed w ith a c id u la te d w ater. The fre e
bromine in the f i l t r a t e was expelled by b o ilin g whereupon
the s o lu tio n was made ammoniacal w ith ammonium hydroxide.
U nfo rtu n ately , the follow ing erroneous r e s u l t s were o btained,
and, being low, in d ic a te probable a b s o rp tio n of beryllium by
the o rganic p r e c i p i t a t e :
a . 0.0839 gm. BeO/25 ml
b. 0.0701 gm. BeO/25 ml
c. True s tre n g th — 0.1013 gm./25 ml
2. P a r t i a l D estru ctio n of
Organic M atter.
The b eryllium c h lo rid e s o lu tio n was tre a te d in the
same manner as before but now subjected to p a r t i a l d e s tr u c
tio n of the organic m atter p re se n t p rev io u s to p r e c i p i t a t i o n .
1 0 ml of co n cen trated n i t r i c acid and 1 0 ml of fuming n i t r i c
acid were added to the s o lu tio n , which was heated up to
about 80°C. The s o lu tio n then turned black and, when i t had
cooled down, the s o lu tio n was c a u tio u s ly made ammoniacal.
In t h i s case the e rro r was a p o s itiv e one, as follow s:
a . 0.1062 gm. BeO/25 ml
b. 0.1027 gm. BeO/25 ml
c. True s tre n g th — 0.1013 gra./25 ml
The beryllium c h lo rid e s o lu tio n , co n tain in g organic
m atter, was a lso tre a te d in sev eral o th e r ways, a l l of them
22
■unsuccessful. In one in s ta n c e , s u lfu r dioxide from a
c y lin d e r was passed in, in the hope th a t the i n t e r f e r i n g
substance, whatever i t might be, would be reduced. This,
however, leads to a s t i l l more incom plete p r e c i p i t a t i o n of
the beryllium hydroxide. In another case, magnesium was
employed in the form of a s o lu tio n of magnesium c h lo rid e in
order to p r e c i p i t a t e the excess oxine, but the u n c e r ta in ty
of i t s subsequent removal forced i t to be given up. The
contam ination introduced by i t s use i s shown in the follow ing
d a t a :
BeO Content/25 ml
0 . 1 0 1 1 gm.
0.0798 gm.
0.0556 gm. — True C oncentration
Data on Successful Modified Method.
The r e s u l t s of using the m o d ific a tio n in procedure,
as given on page 17, were q u ite s a t i s f a c t o r y , and ran a s
f o llo w s :
1. On B eryllium Chloride S o lu tio n s.
25 ml of beryllium c h lo rid e were prepared in the same
way as in the u n su ccessfu l methods; i . e ., 15 ml of 20#
ammonium a c e ta te p lu s in c re a sin g amounts of oxine. However,
the organic m atter was taken care of by the method here
proposed.
23
Volume of Oxine Weight of BeO
5 ml 0.0300 gm.
Set No. 1 10 ml 0.0303 gm.
15 ml 0.0301 gm.
True Amount — 0.0304 gm. BeO/25 ml
5 ml 0.0301 gm.
Set No. 2 10 ml 0.0305 gm.
15 ml 0.0302 gm.
True Amount — 0.0304 gm. BeO/25 ml
2. On A ctual Ore Samples,
Sample No. BeO Content
1 12.09#
2 12.17#
3 12.12#
4 12.16#
Average 12.13# BeO
Data on the Attempted L aboratory P re p a ra tio n
of 8 -H ydroxyquinoline.
1. Conversion of o.-Nitrophenol in to o-Aminophenol.
Reagent Q uantity Weight of Y ield # Yield
o -n itro p h e n o l 40 gms. 28 gms. 90#
sodium hydroxide 1 2 gms.
s u lfu r 1 0 gms.
sodium s u lf id e 80 gms.
water 1 0 0 ml
2. S y n th esis of 8 -H ydroxyquinoline.
24
Reagent Q uantity Weight of Yield ^ Yield
o-aminophenol 25 gms. 5 grams 15%
g ly c e ro l 54 gms.
AS2 O5 9 gms.
Cone. H 2 SO4 44 gms.
CHAPTER IV
CONCLUSION
1. The Value of the 8 -Hydroxyquinoline Method as
Contrasted w ith Other Widely Used Schemes fo r
the S eparation of B eryllium from Aluminum.
In ev a lu atin g a procedure for the s e p a ra tio n of two
elem ents, two p r in c ip a l p o in ts come to o n e 's mind. F i r s t of
a l l , i s the s e p a ra tio n used a b s o lu te ly q u a n tita tiv e , espec
i a l l y w ithout too much regard for s t r i c t experim ental con
d itio n s ? Second, how much time i s involved in c a rry in g out
th a t se p a ra tio n ?
As reg ard s the f i r s t is s u e , the 8 -hydroxyquinoline
method gives a p r e c i p i t a t e which is of the best type a v a i l
able fo r many reaso n s. I t is extrem ely in so lu b le under the
c o n d itio n s of a n a ly s is , f i l t e r s e a s ily , and n o t being of a
g e la tin o u s or c o l lo id a l n a tu re , can be thoroughly washed
w ith cold water and is not a p t to r e t a i n beryllium by ab so rp
tio n . Furtherm ore, the a c e tic acid in the s o lu tio n of the
reag en t in combination w ith the ammonium a c e ta te c r e a te s a
stro n g enough b u ffe r th a t, if one has used too much ammonia
p r io r to the s e p a ra tio n , th e re is l i t t l e chance th a t t h i s
w ill cause an incomplete p r e c i p i t a t i o n of the aluminum oxy-
q u in o la te .
26
Due to the n atu re of the aluminum oxyquj.nol a t e , the
se p ara tio n may be c a rrie d out q u ite ra p id ly and the p r e c i p i
t a t e washed f re e from beryllium in le s s than 45 m inutes.
This is d e f i n i t e l y in c o n tra s t to the Parsons and Barnes
method, in which the s o lu tio n has to be s a tu ra te d re p e a te d ly
w ith COg, in order to e f f e c t a half-w ay q u a n tita tiv e separa
tio n , and is c e r t a i n l y fa r le s s tr y in g and safer than the
Gooch and Havens procedure, c a lli n g fo r the use of d ie th y l
e th e r, an extrem ely inflammable so lv e n t, and the g e n e ra tio n
of hydrogen c h lo rid e gas in a la b o ra to ry .
The 8 -hydroxyquinoline method has the f in a l advantage
of en ab lin g the a n a ly s t e i t h e r to weigh the aluminum in a
s u ita b le form or to d isso lv e i t in acid and t i t r a t e the
re le a se d oxine w ith standard potassium bromate s o lu tio n .
2. S im p lic ity and Time Saving of the Modified Method.
The only p o ssib le inconvenience involved in the oxine
determ in atio n of beryllium i s in the very l a s t ste p , and
th a t i s the te d io u s mode of the d e s tr u c tio n of organic
m atter, in order th a t a l l the beryllium hydroxide may be r e
covered. The sodium carbonate fu sio n , alth o u g h not a c tu a l ly
connected w ith se p a ra to ry method, i s a lso somewhat u n c e rta in .
The r e te n tio n of b eryllium in the s i l i c a in amounts g r e a te r
than th a t of aluminum i s under in v e s tig a tio n in another
la b o ra to ry .
27
For these reasons, the author has attem pted to put
to g e th e r the two a l t e r n a t e procedures of using the n ic k e l
c ru c ib le s in ste a d of platinum and of follow ing a shortened
scheme for d e stro y in g the organic m a tte r. The f i r s t modi-:.-
f i c a t i o n is a b s o lu te ly c e r t a in of being fre e from e r r o r , and
the second is , according to a l l the experim ental data now a t
hand, reaso n ab ly c e rta in of accuracy, and sh o rte n s the time
req u ire d for the follow ing d e s tr u c tio n of o rganic m atter from
3 hours to le s s than an hour.
The author th e re fo r e s in c e r e ly hopes th a t t h i s modi
fie d method may prove i t s worth in the fu tu re and come more
and more into g en e ra l u se.
3. L aboratory P re p a ra tio n of 8-Hydroxyquinoline
v e rsu s Purchase of the Commercial Product.
I t was hoped, when t h i s rese arch was begun, th a t
th e re might be a s u ita b le method to avoid paying $2.90 per
100 grams of oxine re a g e n t, and, for th a t reason, the o rg an ic
p a rt of t h i s work was u n d ertak en .
A fter going through a l l the ste p s n ec essary to get to
the f i n a l product and then n o tin g the u n c e r ta in ty and very
low y ie ld s obtained by the small scale Skraup s y n th e sis, the
author f e e l s th a t i t is v i r t u a l l y im possible to avoid p u r
chasing the commercial re ag e n t.
BIBLIOGRAPHY
BOOKS
M inerals Yearbook 1939, U. S. Dept, of the I n t e r i o r , Bureau
of Mines, pp. 748-751.
S c o tt, Standard Methods of A n a ly s is . 5th E d ., Vol. 1, New
York: D. Van Nostrand Co., pp. 797-8, 800-01.
W illard and Furman, Elementary Q u a n tita tiv e A n a ly s is , 3rd Ed
New York: D. Van Nostrand Co., pp. 406-09.
PERIODICALS
Berg, R ., Z e i t s c h r i f t ftlr a n a ly tisc h e Chemie, 71. S3, 171,
321, 369 (1927); 72, 177 (1927>; 76, 191 (1929); 81, 1
(1930).
Frommes, M., Z e i t s c h r i f t ftlr a n a ly tisc h e Chemie. 95. 287
(1933).
Gibbs, Am. J . S c i . . (2 ), 37, 346.
Gooch and Havens, Am. J . S c i ., (4 ), 4, 111.
Hahn, F. L., e t a l . . Z e i t s c h r i f t fttr a n a ly tis c h e Chemie. 71.
122, 225 (1927).
Knowles, H. B ., Journal of R esearch, U. S. N ational Bureau
of S tandards, .15, 87 (1935).
K olthoff and S an d ell, Jo u rn a l of the American Chemical
S o c ie ty . 50. 1900 (1928).
Parsons and Barnes, Journal of the Amer ican Chemical Society
28, 1589 (1906).
P ollok, T rans. Roy. Dublin Soc.. (2 ), 139 (1904).
Skraup, Z. H ., Wiener M onatsheft fttr Chemie. j3, 536 (1881).
Vauquelin, Ann. Chim. Phys.. 26, 155 (1798).
Wagner and Simons, Jo u rn al of Chemical E ducation. 13, 265
(1936).
29
BIBLIOGRAPHY (Continued)
REFERENCE W ORK
B e ils t e in , e t a l . , Handbuch der organischen Chemie, 4th Ed.,
B e rlin : Verlag von J u liu s S p rin g e r, XXI. 91 (1935).
THESIS
Hunsaker, "Rapid Method for the D eterm ination of B eryllium ,"
M a ste r's T hesis, U n iv e rsity of Southern C a lifo rn ia ,
June, 1933.

Linked assets

University of Southern California Dissertations and Theses

Conceptually similar

PDF

A critical study of the methods for the quantitative determination of beryllium

PDF

A study of the quantitative spectrographic determination of beryllium

PDF

Complex compounds of trimethylamine oxide

PDF

A study of the reactions of phosphorus pentachloride with trimethylamine

PDF

A study of the Mohr and Volhard methods of determination of chloride content in brines

PDF

Addition compounds of trimethylphosphine oxide

PDF

Cryoscopic and conductometric investigations of manganese (VII) and chromium (VI) compounds in sulfuric acid

PDF

An experimental investigation of the interchange of carbon monoxide and cyanide ion in zerovalent nickel compounds

PDF

A study of the reaction of 1-bromo-2-oxoapocamphane in base

PDF

A critical study of the Gooch and Havens hydrochloric acid-ether method for the quantitative separation of beryllium and aluminum

PDF

A method of determining molecular weights of vapors by effusion

PDF

A critical study of the analytical separation of Beryllium from the rar-earth elements

PDF

A survey of the methods for the qualitative detection of the halides

PDF

A study of some oxalates and double oxalates of beryllium

PDF

A critical study of the application of the soap titration method to the determination of calcium and magnesium

PDF

Addition compounds of trimethylamine oxide

PDF

Addition compounds of trimethylamine with boron fluoride and its methyl derivatives.

PDF

An experimental study of the phosphorus chloronitrides and their reactions with trimethylamine

PDF

A study of the structures and properties of triaryl compounds of boron

PDF

A study of methods for the determination of thallium in toxicological analysis

Asset Metadata

Creator Consoli, Vito Warren (author)

Core Title A critical study of the 8-hydro-oxyquinoline method for the determination of beryllium

Degree Master of Science

Degree Program Chemistry

Publisher University of Southern California (original), University of Southern California. Libraries (digital)

Tag chemistry, inorganic,OAI-PMH Harvest

Language English

Contributor Digitized by ProQuest (provenance)

Advisor [illegible] (committee chair), Burg, Anton B. (committee member), Lowy, Alexander (committee member)

Permanent Link (DOI) https://doi.org/10.25549/usctheses-c17-789626

Unique identifier UC11348175

Identifier EP41534.pdf (filename),usctheses-c17-789626 (legacy record id)

Legacy Identifier EP41534.pdf

Dmrecord 789626

Document Type Thesis

Rights Consoli, Vito Warren

Type texts

Source University of Southern California (contributing entity), University of Southern California Dissertations and Theses (collection)

Access Conditions The author retains rights to his/her dissertation, thesis or other graduate work according to U.S. copyright law. Electronic access is being provided by the USC Libraries in agreement with the au...

Repository Name University of Southern California Digital Library

Repository Location USC Digital Library, University of Southern California, University Park Campus, Los Angeles, California 90089, USA