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Патент USA US3097121

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July 9, 1963
G. ASSALINl
3,097,114
PROCESS FOR PURIFYING SUGAR
Filed Aug. 9, 1960
lon
Exchanger
Collecting
United States Patent
Patented July 9,1963
2
1
3,097,114
PC?
3,097,114
In the annexed drawing there is illustratively and-sche
matically shown a plant and the cycle of the various op
'
PROCESS FOR PURIFYING SUGAR
Giuseppe Assalini, Genoa, Italy, assignor to Rohm &
Haas Company, Philadelphia, Pa., a corporation of 5
Delaware
Filed Aug. 9, 1960, Ser. No. 48,548
7 Claims. (Cl. 127-46)
erations relative to the method of this invention. The >
raw sugar juices, even at the elevated temperatures of
preceding sugar processing operations, enter through feed
pipe 1 into collecting tank 2, then through pipe 3 into
the ion-exchanger 4 where there is e?ected the removal
of most of the organic nitrogen in the solution tobe
puri?ed and there is exchanged for the cations present
This‘ invention relates to processes and apparatus for
in the juices the calcium or magnesium ions on the resin
the purification of raw sugar juices by the use of ion 10
in the column.
exchange resins.
The thus treated juices leaving the ion-exchanger pass
through pipe 5 and three-Way valve 6 into mixer 7 which
' Various methods have been known for the puri?cation
of raw sugar juices by ion exchange techniques. Several
contains stirrers ‘8 and which is heated by a steam trans
have been described in my U.S. Patents 2,929,745 and
mitting coil or other such device 9. Also ‘fed into the
15
2,929,746‘. There, processes are set forth which operate
mixer, through pipe 10, is the phosphate, carbonate or
at about 40° C., but it is pointed out that several advan
bicarbonate precipitating aid. Leading from valve 6
tages are obtained through performance of the various
is pipe 11 through which is eliminated the excess water,
operations at room temperatures.
from the ion exchanger 4. The water is conveniently
‘One of the advantages of thus lowering the tempera
collected in tank 12 and ejectedthere?rom as desired
20
ture in those earlier processes is the fact that the anion
7 through pipe 13.
exchan-ge resins which are utilized thereby, either alone
The contents of mixer tank 7 are emptied through
or in a cationic-anionic resin system, could not long with
pipe 14 with the aid of pump 15 and sent through pipe
stand the elevated temperatures before losing their
16 into ?lter 17 where the sugar juices are separated from
capacity to function acceptably. Another advantage
the precipitate which forms in the tank during treatment.
25
resides in the fact that the chances of the resins develop
The ?ltered, puri?ed juices are then passed through pipe
ing acidity, which might cause inversion of the sugar, are
18 into collecting tank 19. Subsequently, the juices are
greatly diminished when the sugar solution to be treated
drawn o? tank 19, through pipe 20 with the aid of a pump
is cooled to room temperatures.
21, and rooted- to evaporation and/or other subsequent
As useful as these and other allied prior art methods
operations (not illustrated in the drawing’).
‘
are, one drawback to their acceptance by certain of the
One of the important :advantagespof the present inven
world’smajor sugar re?ners has been ‘the need to install
tion will readily be appreciated from the foregoing gen
and operate special cooling equipment, particularly in
eral description of the method. ‘It will be noted that
existing plant arrangements. Since, in most sugar proc
there is no provision for the cooling of the sugar juices,
essing plants, the raw juices are obtained from cane and
‘and there needn’t be any, since all of the commercialy'
beets by treatments which culminate in the formation of
available cationic resins are extremely resistant to high
relatively hot sugar-containing solutions, the requirement
temperatures. Another reason for not needing to cool‘
for cooling in ‘order to attain the aforesaid advantages
the solution is that the risk of inverting the sugar isv
has been an economic barrier to the widespread accept
avoided by virtue of the fact that the cationic resin,
ance of any ion exchange treatment incorporating same.
since it is not regenerated with acid, does not produce
My present invention, therefore, will iind universal
any acidity in the liquid treated therewith. V
‘
>
approbation among sugar re?ners because it (a) does‘
‘Other advantages which will be obvious to those skilled
not require any cooling of the juices that are introduced
in the art reside in the fact that the cationic resins have
to the resin beds, (b) avoids passage through any acid‘
much higher exchange capacities and longer useful life
conditions ‘and thus avoids the risk of inversion, and 45 times than anionic resins Which have been used in some
(0) makes possible the attainment of a high purity in
earlier processes, plus the fact that the cationic resins
the treated juices at a lower equipment and operating
are much cheaper than anionic resins.
cost than other ion exchange processes for purifying
The novel process provides exceptionally high purity
sugar.
of the end product, on the order of 96-97%, and conse
The method according to my present invention is char
quently the proportion of extractable sugar in relation to
quantity of raw juices treated reflects a corresponding in
regenerated with a salt, adsorbs the organic nitrogen‘
crease in comparison with the results of prior art tech
which is present in the solution to be puri?ed and thus
niques. Theoperating expenses, in comparison with older‘
acts as a depurant. The cations supplied by the salt are
ion-exchange, sugar processing methods, are considerably
exchanged for the cations present in the juice, and linked 55 reduced because the costs for regenerating the resin and
with organic or mineral anions to form organic complexes
tor the ?occulating adjuvants are much lower.
or mineral salts which can readily be eliminated by form
The following examples are ‘further illustrative of the
ing a ?occulent precipitate and ?ltering. To aid in form
invention:
'
ing this ilocculent precipitate the liquid is treated with a
Example 1
compound which is capable of increasing the amount of 60
acterized by the fact that a cationic resin, which has been
{?occulation and, simultaneously, acts as a defecant or.
depurant and also is able to adjust the pH to the desired
values.
_
An ion-exchange column was employed which was
about 40 mm. in diameter. It contained approximately
700 cc. of a well-known, strongly acidic cation-exchange
resin, a cross-linked styrene-divinylbenzene copolymer
The salts which are used for regenerating the cationic
resin preferably are those which will furnish group II 65 having sulfonated functional groups. The height of the
resin bed was about 56‘ cm. The resin was regenerated
cations, calcium, and magnesium being the ones that are
with 13 lbs/cu. ft. of a 10% aqueous solution of CaClz
particularly attractive in this process. The organic com
at a ?ow rate of 1 gal./cu. ft./rnin., followed by a water
plexes ‘or mineral salts precipitated by treatment of the
rinse of 8 vols/resin vol. initially at the same ?ow rate
e?iuent (which is obtained when the sugar juices are
stepped up to 2 gal./_cu. ft./ min.
I
passed over the resin) are precipitated with the aid of a 70 butAlater
total of 4980‘ cc. of diffusion juice, corresponding to
soluble hydroxide, phosphate, carbonate or bicarbonate
of ammonia or the ‘alkali metals.
7 vol./ resin vol., was passed through the resin column at
3,097,114
4
a flow rate of 180 cc./min. The analysis of the diffusion
lime milk in a quantity corresponding to 0.26% juice of
CaO. The light yellow ?ltrate analyzed as follows:
juice was:
Bx ______________________________________ __ 13.10
Sucrose _____________ __>____. __________________ __
Bx ______________________________________ __ 11.34
Sucrose __________________________________ __ 10.50
11.05
Purity ___________________________ __percent__ 84.35
Temp ______________________________ __° C__
Purity ___________________________________ __ 92.59
35
Example 3
An ion-exchange column was employed which was
about 4 mm. in diameter. It contained approximately 700
Fraction A.—-This fraction was not initially analyzed. 10 cc. of a well-known, strong acidic cation-exchange resin,
a cross-linked styrene-divinylbenzene copolymer having
It was treated with 0.3% lby weight of the juice of a con
The ?rst 500 cc. of ei?uent contained no sucrose and
was eliminated. The subsequent effluent was collected in
three fractions of 1660 cc. each.
centrated (100%) NaOH solution. The NaOH solution
sulfonated functional groups. The height of the resin bed
was at 38.8 Bé. and cool.
was about 56 cm. The resin was regenerated with 13
lbs./ cu. ft. of a 10% aqueous solution of CaCl2 which
The solution was heated to
80° C. and ?ltered. The analysis of the rather limpid 15
and light yellow juice was:
solution had been acidi?ed with HCl to a pH of 3 in order
to aid in the recovery of any amino-acids adsorbed by the
Bx ______________________________________ __ 11.60
Sucrose __________________________________ __ 11.25
resins.
Fraction B.-—This fraction was analyzed before further
treatment, its content being as follows:
vols./resin vol. at the same ?ow rate except near the end
20 When it was doubled.
A total of 14 liters of diffusion juice, corresponding to
20 VOL/resin vol., was passed through the resin column at
a ?ow rate of 160 cc./min. The analysis of the diffusion
juice was:
Bx ______________________________________ __ 11.46
Sucrose _.. ___________ _- ______________________ _.
The regeneration was carried out at a ?ow rate
of 1 gal/cu. ‘ft./min., followed by a water rinse of 8
Purity ___________________________________ __ 96.98
10.91
Purity ___________________________________ __ 95.20 25
Bx _______________________________________ __ 11.80
This solution was heated to 80° C. and then treated
Sucrose __. __________________________________ __
with 0.4% (by weight of the juice) of a concentrated
9.80
Purity ___________________________________ __ 83.05
Temp __\_____________________________ __° C__
35
(100%) NaOH solution. The NaOH solution was at 38.8
Bé. and cool. The thus treated juice was ?ltered; the 30
The ?rst 500 cc. of effluent contained no sucrose and
darker ‘but likewise limpid juice had the following anal
was eliminated. The subsequent effluent was collected
ys1s:
and found to have the following analysis:
Bx _______ __' _____________________________ __
12.11
Sucrose ___________________________________ __ 11.70
Purity ___________________________________ __ 96.61
Bx ______________________________________ __ 10.02
35
Sucrose ____ __
,
___-.-
_
.
9.40
Purity ___________________________________ __ 93.81
Fraction C.—This fraction was not initially analyzed.
The effluent was heated to 80° C., and then treated
with lime milk ‘in a quantity corresponding to 0.50% juice
of CaO. After this treatment a ?rst carbonation (with
CO2) ‘was canried out until the solution had a pH of 9,
The juice was heated to 80° C. and then treated with lime
milk in a quantity ‘corresponding to 0.2% juice of CaOl.
The light colored, limpid ?ltrate had the following anal
ysis:
at 'which time it was ?ltered. The ?ltrate was subjected
Bx _'_ ____________________________________ __
11.84
Sucrose .'.-L _____ __.__..._: _______________________ __
11.35
to a second carbonation until the pH was 7.8 'when it was
?ltered. The ?ltrate had the following analysis:
Purity ______ _'_ ___________________________ __ 95.86
45
Example 2 7
__
10.09
Sucrose _________ ___. _____ __- _________________ _.
Bx
___
9.40
Purity ___________________________________ __ 93.16
An ion-exchange column, prepared and regenerated as
Example 4
described in Example 1, was employed. A total of 12,600
cc. of diffusion juice, corresponding to 18 vol/resin vol., 50
An ion-exchange column, prepared and regenerated ex
was passed through the resin column at a flow rate of 180
actly [as described in Example 1, was employed. A total
cc./min. The analysis of the diffusion juice was:
of 28 liters of diffusion juice, corresponding to 40 vol./
Bx ______________________________________ __ 12.19
Sucrose __________________________________ __ 10.40
Purity ___________________________________ __ 85.31
Temp
___
___
__° C__
35
‘ resin vol., was passed through the resin column at a
?ow rate of 100 cc./min. The analysis of the diffusion
55 juice was:
Bxv
After the ?rst 500 cc. had been eliminated, the e?iuent
was collected in three fractions of 4900 cc. each, two of
which were treated as follows:
Fraction A.—-This fraction was not initially analyzed.
____
_____ __
Sucrose
9.85
Purity
Temp __
11.80
____ __ 83.47
___-
_° C__
35
60
After the ?rst 500 cc. had been eliminated, the effluent
was collected in four 7000 cc. fractions which analyzed as
follows:
It (was heated up to 80° C. and then treated with lime milk
in a quantity corresponding to 0.18% juice of CaO. The
light yellow ?ltrate was found on analysis to contain:
A
65
B I o
D
Bx ______________________________________ __ 10.80
Sucrose ._ ___________________________________ __ 10.30
Purity ___________________________________ __ 95.37
Bx _______________________________
Sucr0se_____
Purity ____ -_
Fraction B.-—This fraction was analyzed before treat
ment and found to contain:
70
BX ___.‘ _____________ .--V ____________________ _._
-
10. 4o
10. 40
10. 65
11. 05
9. 70
9. 80
9. 55
9. 70
93.27
94.23
89.67
87.78
Example 5
11.0
Sucrose __________________________________ __ 10.30
Purity ____________________________________ __ 93.64
An ion-exchange column, prepared and regenerated ex
actly as described in Example 1, was employed. A total
of 25 liters of diffusion juice, corresponding to 35 vol./
The solution was heated to 80° C. and then treated with 75 resin vol., was passed through the resin column at a ?ow
3,097,114
was:
Bx
'
‘
‘
____
11.45
Sucrose.
_
6
described in Example 1, was employed.‘ A total of 20
liters of diffusion juice, corresponding to 30 vol./ resin vol.,‘
was passed through the resin column at a ?ow rate of
100 cc.'/min. The analysis of the‘ diffusion juice was:
rate of 150 cc./min. The analysis of the dilfusion‘juice
9.40
Purity
_____ 82.09
Bx ___
Temp
° C__
Sucrose
35
Temp
was collected in four 6000 cc. fractions which analyzed
Bx _________________________________ ._
Sucrose _________ __
B
o
10.17
10.37
10.55
v
Purity _____________________________ -_
juice was:
10.48
Bx ___
Sucrose
9. 35
9. 45
9. 35
9. 25
91.13
88.63
88.26
° C__
35
lected together. The average analysis of the resulting
D
91.94
82.47
_
After eliminating the ?rst 500 cc., the effluent was col
10
A
3-10.35
Purity
- After the ?rst 500 cc. had been discarded, the ef?uent
as follows:
12.55
_
15
Purity .... __
11.46
‘ 10.40
_
790.75
Example '9
Example 6
An ion-exchange column, prepared and regenerated as
An ion—exchange column, prepared and regenerated ex
described in Example 1, was employed. A total‘ of'25
actly as describedin Example 1, was employed. A total 20 liters of di?usion juice, corresponding to 35 vol/resin
of 25 liters of diffusion juice, corresponding to 35 vol./
resin vol., was passed through the resin column at a ?ow
mate of 100 cc./min. The analysis of the diffusion juice
was:
BX
_ __ _ __
Sucrose
’
h
'
. . _ _ _ _ _ __
l
Purity‘-
‘
V
'
12.50
‘
Purity ,
__
--_
85.35
° C__
35
84.00
_° C___
_ After eliminating the ?rst 500 cc., the effluent was col
35
After elimination of the ?rst 500 cc. the effluent was
30
collected in four 6000 cc. fractions, the ?rst three of
which ‘analyzed as follows:
lected together. The average analysis of the resulting
juice was:
Bx
Sucrose
A
g
Temp ,
10.50
_
Temp _’
vol., was passed through the resin column at a ?ow rate
of 80 cc./-min. The analysis of the diffusion juice was:
Bx
11.95
10.20
25 Sucrose
V B
o
11.20
11. 30
--_ 11.26
.._
10.40
a
Purity '._'_'_'
92.36
35
Example 10
129
10. 92
_
.
'
'
A=n ion-exchange column, prepared and regenerated as
described in Example 1, was employed. ,A total of 20
liters of diffusion juice, corresponding to 30 vol/resin
Fraction B was heated to 80° C. and then treate‘dwith 40 vol., was passed through at a ?ow rate of 80 cc./min.
0.40% juice of concentrated (100%) 'NaOH. The NaOH
The analysis of the dilfusion juice was:
_______________ -_
10.10
10. 2o
'9. 9o
Purity ____________________________ -__ .... -._-.-
Sucrose ____________________
92. 49
91.07
37. e1
solution was at 38.8 Bé. The treated ‘solution was then
12.15
?ltered, the dark, limpid ?ltrate analyzing as follows:
Bx
--_-
____
Sucrose _
Sucrose
11.10
45 Purity
_ 10.70
Purity
__
Temp
96.40
Fraction C was heated to 80° C. and then treated with
84.76
35
___° C__
After eliminating the ?rst 500 cc., the effluent was col
lected in four fractions which analyzed as follows:
lime milk in a quantity corresponding to 0.70% juice of
CaO. The solution was ?ltered, and the light yellow ?l
trate analyzed as follows:
Bx
_ 10.30.
50
A.
B
C
D
_ ________ _____ 12.30
Sucrose
Purity
10.-85
11.30
_____ .._ 87.50
10. 10
89. 38
-
11. 50
10.76
l 9.80‘
85. 22 .
9. 60
89. 22
Example
: An ion-exchange column, prepared and regenerated as
Fractions A and B comprised 5000 cc., fraction C was
described in Example 1, was employed. A total of 20
liters of diffusion juice, corresponding to 30 VOL/resin
4000 cc., and fraction D was 6000 cc. Each of the frac
tions was heated to 80° C. and then treated with lime milk
3101., was passed through-the resin column at a ?ow 'rate 60 in ia'quantity corresponding. to 0.80% juice of CaO, car
of 250 cc./1nin. The analysis of the diffusion juice was:
bonated with CO2 up to pH 8, and ?ltered. The limpid
Bx
and light colored ?ltrates analyzed as follows:
____ 12.35
Sucrose
Purity
Temp
‘’ C__
85.83 65
35
juice was:
B
10. e2
9. 70
91. 34
o
10. 89
9. so
88.39
D
10. 1e
9. 4o
92. 52
.
Bx ________________ __' .... _. ______________ __ 11.36
-._-
Purity
K
A
10. 55
10. 1o
95. 7a
After eliminating the ?rst 500 cc., the effluent was col
lected together. The average analysis of the resulting
Sucrose
'
_ 10.60
__
10.60
70
‘Example _11
93.31
An ion-exchange column, prepared and regenerated as
described in Example 1, was employed. A total of 20
An ion-exchange‘ column, prepared ‘and regenerated as
liters of diffusion juice, corresponding to 30 vol./resin
_
Example 8
3,097,114‘
vol., was passed through at a ?ow rate of 80 cc./min.
The analysis of the dithrsion juice was:
Bx
Sucrose
vol, was passed through at a flow rate of 120 cc./min.
The analysis of the diffusion juice was as follows:
12.25
10.30
Purity
t
r
__
1
Sucrose
BX -_--;-_.&
_________________________________
---------------------------------- __
-._ 10.00
84.08
Temp
_
° C__
Purity ____-
35
After eliminating the ?rst 500 cc., the e?iuent was col
lected in four fractions of 5000 cc. each; they analyzed as
follows:
10
BX ...... -i _____________ -5 ________ _. _
Sucrose _________________ __
_
Purity _______________________ __
A
B
C
10.21
9. 50
93. 04
10. 77
9. 80
90.99
84.70
10.77
_________________________________ ._ 10.05
Purity
11. 11
9. 90
89. 10
_
Bx ___________________ _t ...... __, __________ __
Sucrose
D
11
9. 90
90.00 -
--_‘
Temp ______________________________ .._° C__
35
After eliminating the ?nst 500 cc. the e?luent was col
lected and ‘analyzed as follows:
_.__\.._
V
93.31’
Example‘ 15
15
Example 12
An ion-exchange column, prepared and regenerated as
described in Example 1, was employed. A total of 20
liters of di?usion juice, corresponding to about 30
An iron column, having a diameter of 100 mm., was
used in this ‘experiment. It contained about 15 liters of
the same resin described in Example 1 ‘above. The height
of the resin was about 150 cm. Regeneration of the
resin was carried out with a 10% solution of CaCl2, the
regeneration level being 13 lbs/cu.
A total of 450
liters of diffusion juice, corresponding to about 30
vol./re~sin vol., was passed through at a flow rate of 80
Ice/min. The analysis of the diffusion juice was as fol~
vol/resin voL, was passed through at a ?ow rate of
lows:
as follows:
2000 cc./min. The analysis of the diifusion juice was
'
25
Bx
__
_
After eliminating the ?rst 500 00., the e?luent was col
lected and analyzed as follows:
V
___
Sucrose
Purity _
--_
30
11.40
10.30
90.35
83.13
Temp __________________________ __‘____° C__
35
12.45
_________________________________ __ 10.35
Purity
84.97
Temp. ____________________ _.- ________ .._° 0--
._
Sucrose
10.70
Purity _
Bx
BX .._--. ______ .._-4 _____ __.__. ____ _;-__._'. _____ __'____
--_.-- 12.60
Sucrose
35
A?ter the ?rst 10 liters, which contained no sugar, were
eliminated, the e?‘luent was collected in nine fractions of
50 liters each. The analytical data for each fraction were
as follows:
35
Fraction
Bx
Sucrose
Purity
The e?luent was then heated to 80° C. and treated with
lime milk in a quantity corresponding to 0.80% juice of
CaO. 'The limpid and light colored ?ltrate analyzed as
40
follows:
A-.
10. 93
B__
_
C__
D_
E__
...... __
F__
Bx
Sucrose
___..
_____
--_-
_
_
G__
H-
11.20
_________________________________ __ 10.70
.
9. 90
90. 57
10. 87
9. 80
90.15
11. 40
10.50
92.10
11. 20
10.30
91. 96
10.92
10.00
91.57
11. 45
10.40
90.82
11.48
11.08
11. 30
10. 40
10. 10
10. 20
90. 59
91. 15
90. 26
Purity ___________________________________ .._ 95.53
45
Example 13
An ion-exchange column, prepared and regenerated as
described in Example 1, was employed. A total of 40
liters of ‘diffusion juice, corresponding to about 60 vol/
resin vo1., was passed through at a ?ow rate of 80 cc./min.
The analysis of the diffusion juice was as tollows:
The fractions were then collected together, heated to
80° 0., treated withv lime milk corresponding to 0.80%
juice of OaO, and ?ltered. The light colored and limpid
?ltrate analyzed ‘as follows:
Bx
n ___,_
Sucrose
_____ __
Purity
Bx _
Sucrose
.._-
_
Purity
_
12.15
__
10.10
_ 83.12
Temp
_° C__
35
55
_
_ __
1 1.07
The e?luen-t was then heated to 80° C. and treated
Bx
_ 10.67
_____ .._ 95.49
This juice was conveyed to evaporation and crystal
lization with the production of ?rst and second products
and ?nal molasses.
follows:
1. Process for the puri?cation of sugar juices by means
of synthetic ion exchange resins without ?rst cooling
them after extracting the raw juices from their natural
sources, comprising, treating the undefe'cated sugar juices
Sucrose _________________________________ __ 10.10
Purity .._1
91.24
with lime milk corresponding to 0.70% juice of CaO.
The limpid, light colored ?ltrate analyzed as follows:
10.60
The embodiments of the invention in Which an ex
clusive property of privilege is claimed are de?ned as
After eliminating the ?rst 500 cc., the effluent was col
lected and analyzed as ‘follows:
Bx
11.10
__
65
with a cation-exchange resin which has on its exchange
sites group II metallic cations which will react with solu
ble alkali metal and ammonia hydroxides, phosphates and
carbonates to form a ?occulent precipitate, heating the
thus treated juices to a temperature even higher than what
they had before being contacted with the ion-exchange
resin, then reacting the heated juices with a compound
70 from the class consisting of soluble hydroxides, phos
Example 14
phates, carbonates and hicarbonates of ammonia and
the
alkali metals, whereby a ?occulent precipitate of
An ion-exchange column, prepared and regenerated as
organic complexes and mineral salts forms, and ?nally
described in Example 1, was employed. A total of 20
removing the precipitate from the thus puri?ed sugar
liters diffusion juice, corresponding to about 30 vol/resin 75 juices.
Sucrose _________________________________ __
9.90
Purity _______ __
92.78
3,097,114
2. Process of claim 1 in which sodium hydroxide is
the compound used to react with the heated juices to
form the ?occulent precipitate which is removed to leave
puri?ed sugar juices.
3. Process of claim, ll in which calcium hydroxide is 5
the compound used to react with the heated juices to
10
6. Process of claim 5 in which the cation exchange
resin is in the calcium form.
7. Process of claim 5 in which the cation exchange
resin is in the magnesium form.
References Cited in the ?le of this patent
UNITED STATES PATENTS
form the ?occulent precipitate which is removed to leave
puri?ed sugar juices.
4. Process of claim '1 followed by the steps of evapo
rating and crystallizing the sugar from the puri?ed sugar 10
juices.
5. Process of claim 1 in which the cations on the ex
change sites of the resin are from the class consisting of
calcium ‘and magnesium.
2,568,925‘
2,635,061
2,678,288
Mills _______________ __ Sept. 25, 1951
McBurney ___________ __ Apr. 14, 1953
Cotton et al ___________ __ May 11, 1954
2,929,746
2,988,463
Assalini _____________ __ Mar. 22, 1960
Vajna _______________ __ June 13, 1961
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