United States Patent [19]
Kindig et ale
[11]
[45]
4,205,979
Jun. 3, 1980
[54] PROCESS FOR BENEFICIATING OXIDE
ORES
[75] Inventors: James K. Kindig, Arvada; Ronald L.
Turner, Golden, both of Colo.
[73] Assignee: Hazen Research, Inc., Golden, Colo.
[21] Appl. No.: 950,176
[22] Filed: Oct. 10, 1978
[51] Int. Ct.2 C22B 1/06
[52]· U.S. Ct•......................................... 75/1 II; 75/21;
209/214; 427/252
[58] Field of Search 75/1 R, 1 T, 21, 28,
75/62,72,77,82,81, 111, 112; 423/23, 13 P, 25;
204/217,213,214;427/47,252,253,254,255
[56] References Cited
U.S. PATENT DOCUMENTS
41 Claims, No Drawings
FOREIGN PATENT DOCUMENTS
179095 7/1954 Austria 75/112
119156 8/1959 U.S.S.R 209/212
Primary Examiner-L. Dewayne Rutledge
Assistant Examiner-Michael L. Lewis
Attorney, Agent, or Firm-Sheridan, Ross, Fields &
McIntosh
In a process for beneficiating one or more mineral values
ofa metal oxide ore selected from the group consisting
of bauxite, taconite, chrysocolla, apatite, titanium
oxides and the metal oxides of Groups IIIB, IVB, VB,
VIB, VIIB, VIIIB, IB, lIB and IVA by treating the ore
with a metal containing compound, preferably iron
carbonyl, under conditions such as to selectively enhance
the magnetic susceptibility of the mineral values
to the exclusion of the gangue in order to permit a separation
between the values and gangue, the improvement
comprising pretreating the metal oxide ore by heating it
to a temperature of at least about 80· C. for a time period
of at least about 0.1 hours.
Kindig et aI 44/1 R
Glasser 75/1 T
McEwan et al. 423/417
Kindig et aI 44/1 R
ABSTRACf
211976
8/1976
1111977
7/1978
3,938,966
3,977,862
4,056,386
4,098,584
[57]
Etherington 75/1 R
Grams 75/1 T
Dean et al. 423/25
Drummond 427/252
Altmann 75/0.5
Queneau et al. 75/0.5
Queneau 427/217
Frysinger et aI 75/119
O'Neill et al. 75/0.5
IlIis et al. 75/112
Knisky et aI. .. 423/25
Sato 423/25
211913
111931
10/1938
10/1943
9/1952
7/1960
1111965
5/1966
6/1967
9/1969
111970
6/1972
1,053,486
1,789,813
2,132,404
2,332,309
2,612,440
2,944,883
3,220,875
3,252,791
3,323,903
3,466,167
3,490,899
3,669,644
4,205,979
5
1
PROCESS FOR BENEFICIATING OXIDE ORES
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention is an improvement on a means for
treating ores to separate the mineral values from gangue
material by selectively enhancing the magnetic susceptibility
of the mineral values so that they may be mag- 10
netically removed from the gangue.
2. Description of the Prior Art
As is well known, mining operations in the past for
recovering various metals (e.g., lead and copper) have
utilized high grade ore deposits where possible. Many 15
of these deposits have been exhausted and mining of
lower grade ores is increasing. The processing of these
leaner ores consumes large amounts of time, labor, reagents,
power and water with conventional processing.
In addition to the increased expense associated with 20
the extraction of these metals from low· grade ores,
proposed processes for separation of certain of the sulfide
ores are technically very difficult and involve elaborate
and expensive equipment. In many cases the expense
incurred by such separation would be greater 25
than the commercial value of the metal, such that the
mineral recovery, while theoretically possible, is economically
unfeasible.
Our copending patent application Ser. No. 921,583
filed July 3, 1978 entitled "Process For Beneficiating 30
Oxide Ores" teaches the treatment of oxide ores with a
metal containing compound under conditions such as to
selectively enhance the magnetic susceptibility of the
mineral values to the exclusion of the gangue, allowing
for a separation of these values from the gangue. How- 35
ever, it appears as though the presence of various volatile
compounds within the ore can have an adverse
effect on the recovery of mineral values in a process
which enhances the magnetic susceptibility of the min- 40
eral values. Pretreating the raw oxide ore with heat in
order to volatilize these various components, and thereafter
selectively enhancing the magnetic susceptibility
of the mineral values so that they may be physically
separated from the gangue, substantially enhances the 45
effectiveness of the separation of the mineral values
from the gangue. Additionally, pretreatment with heat,
optionally in the presence of various gaseous additives,
enhances the basic process, apparently as a result of
differing mechanisms. 50
SUMMARY OF THE INVENTION
The process of the present invention entails heat pretreatment
of a metal oxide ore selected from the group
consisting of bauxite, taconite, chrysocolla, apatite, 55
titanium oxides and the metal oxides of Groups IIIB,
IVB, VB, VIB, VIIB, VIIIB, IB, lIB, and IVA, and
thereafter treating the metal oxide ore with a metal
containing compound, preferably iron carbonyl, under
conditions such that the magnetic susceptibility of the 60
ore is. selectively enhanced to the exclusion of the
gangue. The affected or values may then be separated
from the gangue, preferably by means of a magnetic
separation.
The pretreatment is conducted at a temperature of at 65
least about 800 C. for a time period of at least about 0.1
hours. The heat pretreatment step may also be conducted
in the presence ofone or more gaseous additives,
2
for example, steam, nitrogen, hydrogen, carbon monoxide,
hydrogen sulfide, ammonia, and sulfur dioxide.
DESCRIPTION OF THE PREFERRED
EMBODIMENTS
The process of the present invention is particularly
useful for concentrating metal oxide minerals. The process
employs the heat pretreatment of the metal oxide
ore with heat or heat in conjunction with a gaseous
additive, and thereafter treating the ore with a metal
containing compound, preferably iron carbonyl, under
conditions such as to selectively enhance the magnetic
susceptibility of various mineral values contained
within the ore. The treated mixture can then be subjected
to a separation process to produce a beneficiated
product.
The heat pretreatment of the present invention is
conducted prior to initiating the reaction with the metal
containing compound. This pretreatment essentially
comprises heating the metal oxide ore in order to render
the ore more receptive to the magnetic enhancement
reaction. Thetemperature and time ofheating are interrelated,
and essentially higher temperatures require less
time. The particular time and temperature for the pretreatment
process will depend on the particular ore
being beneficiated and also the metal containing compound
with which the ore is later treated. Since metal
oxide ores as a group do not readily decompose with
heat, the pretreatment may occur over a broad range of
temperatures. The temperature must not exceed the
decomposition temperature of the mineral value, or a
temperature above which substantial vaporizaton
would occur. It is gel).erally preferred that the pretreatment
essentially comprise heating the ore to a temperature
of at least about 800 C., more preferably from about
1250 C. to about 5000 C. and most preferably to a temperature
of from about 1750 C. to about 2500 C. It is
preferred that this heat pretreatment be done for a time
period of at least about 0.1, more preferably from about
0.20 to 4 hours, and most preferably from about 0.25 to
about 1 hour.
The heat pretreatment need not be immediately followed
by the magnetic enhancement reaction. Hence,
the ore may be permitted to cool to ambient temperature,
or any other convenient temperature, prior to
conducting the magnetic susceptibility enhancement
reaction. However, if the heat pretreatment is conducted
at a temperature greater than the temperature of
the magnetic enhancement reaction, the ore must be
cooled to at least thetemperature at which the magnetic
enhancement reaction will be conducted.
It is generally preferred to maintain the heat pretreatment
temperature at least slightly above the temperature
of the magnetic enhancement reaction. This is not
an imperative requirement, however, improved results
are generally accomplished. The pretreating by heating
the ore is believed to change the ore either physically or
chemically and/or be volatilize various components
which can interfere with the magnetic enhancement
reaction. Therefore, if the magnetic enhancement reaction
is conducted at a temperature in excess of the pretreatment
temperature, it is possible that additional volatile
components could somewhat detrimentally affect
the magnetic enhancement reaction.
The heat pretreatment step may be conducted in the
presence of one or more gaseous additives, and this is
preferable under many circumstances. Examples of
suitable gaseous additives include steam, nitrogen, hy4,205,979
3
drogen, carbon monoxide, carbon dioxide, ammonia,
hydrogen sulfide, sulfur dioxide, methane, air, ethane,
propane, butane and other hyrocarbon compounds in
the gaseous state at the pretreatment temperature. Preferred
gaseous additives include steam, nitrogen, hydro- 5
gen, carbon monoxide, hydrogen sulfide, ammonia and
sulfur dioxide.
When these additives are. employed it is preferable
that they be employed in an amount of at least about 2,
more preferably at least about 12, and most preferably 10
at least about 120 cubic meters per hour per metric ton
of ore being processed.
A particular preferred additive is steam. Heat pretreatment
with steam is preferably conducted at a temperature
of at least about 1000 C., more preferably from 15
about 1500 C. to about 3500 C., and most preferably
from about 1750 C. to about 2500 C. Preferably, the
pretreatment should be conducted for at least about 0.1
hours, more preferably for at least about 0.25 hours, and
most preferably for at least 0.5 hours. The amount of 20
water preferably ranges from about 1% to about 50%,
more preferably from about 5% to about 30%, and most
preferably from about 10% to about 25%, based on the
weight of the metal oxide ore being treated.
After the ore has been subjected to this heat pretreat- 25
ment, it is then treated with a metal containing compound
in order to selectively enhance the magnetic
susceptibility of its various mineral values.
"Enhancing the magnetic susceptibility" of the ore as
used herein is intended to be defined in accordance with 30
the following discussion. Every compound of any type
has a specifically defined magnetic susceptibility, which
refers to the overall attraction of the compound to a
magnetic force. An alteration of the surface magnetic
characteristics will alter the magnetic susceptibility. 35
The metal containing compound treatment of the process
alters the surfacr characterisics of the ore particles
in order to enhance the magnetic susceptibility of the
particles. It is to be understood that the magnetic susceptibility
of the compound is not actually changed, but 40
the particle itself is changed, at least at its surface, resulting
in a particle possessing a greater magnetic susceptibility
than the original particle. For convenience of
discussion, this alternation is termed herein as "enhancing
the magnetic susceptibility" of the particle or ore 45
itself.
The metal oxide minerals which are capable of undergoing
a selective magnetic enhancement in accordance
with the process include the metal oxides of Groups
IIIB, IVB, VB, VIB, VIIB, VIIIB, IB, lIB and IVA, 50
the titanium oxides of Group IVB, aluminum hydrate,
i.e. bauxite, of Group IIIB, taconite, chrysocolla, and
apatite. It is recognized that taconite and chrysocollar
are classified as silicates and apatite is classified as a
phosphate, and it is further recognized that apatite does 55
not contain elements generally classified as metals
(other than calcium). However, for the purposes of this
inventive process they are classified as metal oxides.
The preferred oxide minerals include bauxite, apatite,
cuprite, cassiterite, carnotite, scheelite, chrysocolla and 60
hematite.
The gangue minerals from which the metal oxide ores
can be separated include those minerals which do not
undergo a sufficient magnetic susceptibility enhancement
as a result of the process. These gangue minerals 65
include, for example, silica, alumina, gypsum, muscovite,
dolomite, calcite, albite and feldspars, as well as'
various other minerals.
4
In those ores which contain naturally relatively
strongly magnetic constituents, such as magnetite, the
magnetic material may first be removed by passing the
mixture through a magnetic separator. The nonmagnetic
portion obtained by this precleaning step is then
subjected to the heat pretreatment and then treatment
with a metal containing compound. Prior to either of
the treatments, the ore must be ground to liberate the
metal oxide particles from the gangue particles, if the
respective components do not already exist in this liberated
state. The ore may be crushed finer than necessary
to achieve liberation, but this is not generally economically
possible. It is generally satisfactory to crush the
ore to minus 14 mesh, although many ores require
grinding to minus 65 mesh or finer.
Numerous metal containing compounds are capable
of enhancing the magnetic susceptibility of these metal
oxides in accordance with the invention. Many iron
containing compounds possess the capability of enhancing
the magnetic susceptibility of the mineral values of
the ore, as long as the compound is adaptable so as to
bring the iron in the compound into contact with the
mineral value under conditions such as to cause an alteration
of at least a portion of the surface of the mineral
value.
Iron containing compounds capable of exerting sufficient
vapor pressure, with iron as a component in, the
vapor, so as to bring the iron into contact with the value
at the reaction temperature are suitable, as well as other
organic and inorganic iron containing compounds
which can be dissolved and/or "dusted" and brought
into contact with the mineral value contained within the
ore. Preferred compounds within the vapor pressure
group are tl~ose which exert a vapor pressure, with iron
as a component in the vapor, of at least about 10 millimeters
of mercury, more preferably of at least about 25
millimeters of mercury and most preferably of at least
about 50 millimeters of mercury at the reaction temperature.
Examples of groupings which fall within this
vapor pressure definition include ferrocene and its derivatives
and beta-diketone compounds of iron. Specific
examples include ferrocene and iron acetylacetonate.
Other organic compounds which may be utilized to
enhance the magnetic susceptibility include those
which may be homogeneously mixed with a carrier
liquid and brought into contact with the components of
the ore. Such mixtures include, for example, solutions,
suspensions and emulsions. These compounds must be
such as to provide sufficient metal to contact the surface
of the mineral value. Suitable carrier liquids include, for
example, acetone, petroleum ether, naptha, hexane,
benzene and water; but this, of course, is dependent
upon the particular metal compound being employed.
Specific groupings include, for example, ferrocene and
its derivatives and the carboxylic acid salts of iron, such
as, iron octoate, iron naphthenate, iron stearate and
ferric acetylacetonate.
Additionally, solid organic iron containing compounds
capable of being directly mixed with the ore in
solid form possess the capability of enhancing the magnetic
susceptibility of the metal sulfides. The compound
must be in solid form at the mixing temperature and be
of sufficiently fine particle size in order to be able to be
well dispersed throughout the ore. The particle size is
preferably smaller than about 20 mesh, more preferably
smaller than about 100 mesh, and most preferably
smaller than about 400 mesh. Compounds within this
grouping include ferrocene and its derivatives, iron salts
4,205,979
5
of organic acids, and beta-diketone compounds of iron.
Specific examples include ferrous formate, 1,1'-diacetylferrocene,
and l,l'-dihydroxymethyl ferrocene.
Various inorganic compounds are also capable of
producing an enhanced magnetic susceptibility. Pre- 5
ferred inorganic compounds include ferrous chloride,
ferric chloride and the metal carbonyls, including, for
example, iron, nickel, cobalt, molybdenum, tungsten
and chromium carbonyls and derivatives of these compounds.
Iron carbonyl is a preferred carbonyl for im- 10
parting this magnetic susceptibility, particularly iron
pentacarbonyl, iron dodecacarbonyl and iron nonacarbonyi.
The more preferred metal containing compounds
capable of enhancing the magnetic susceptibility
are iron pentacarbonyl, ferrocene, ferric acetylac- 15
etonate, ferrous chloride and ferric chloride, with iron
pentacarbonyl being the most preferred.
The process is applied by contacting the iron containing
compound with the ore at a temperature wherein
the iron containing compound selectively decomposes 20
or otherwise reacts at the surface of metal oxide particles
to alter their surface characteristics, while remaining
essentially unreactive, or much less reactive, at the
surface of the gangue particles. The temperature of the
reaction is a critical parameter, and dependent primarily 25
upon the particular compound and the particular ore.
The preferred temperature can be determined by heating
a sample of the specific iron containing compound
and the specific ore together until the decomposition
reaction occurs. Suitable results generally occur over a 30
given temperature range for each system. Generally,
temperatures above the range cause non-selective decomposition
while temperatures below the range are
insufficient for the reaction to occur.
While as indicated above, techniques other than 35
vapor injection methods may be employed as applicable
depending upon the metal· containing compound being
utilized, the following discussion primarily applies to
vapor injection techniques, specifically iron pentacarbonyl,
as these are generally preferred. Similar consid- 40
erations, as can be appreciated, apply to the other described
techniques.
The preferred temperatures when iron pentacarbonyl
is employed as the treating gas are primarily dependent
upon the ore being treated. It is generally preferred to 45
select a temperature which is within a range of 125° C.,
more preferably 50° C., and most preferably 15° C.less
than the general decomposition temperature of the iron
carbonyl in the specific system. The general decomposition
temperature is intended to mean the temperature at 50
which the iron carbonyl decomposes into iron and carbon
monoxide in an indiscriminate fashion, causing a
magnetic enhancement of the gangue as well as the
metal oxide. The "specific system" is intended to include
all components and parameters, other than, of 55
course, temperature, of the precise treatment, as the
general· decomposition temperature generally varies
with different components and/or different parameters.
This decomposition temperature range can be readily
determined by analytical methods, and often a trial and
6
error approach is preferred to determine the precise
temperature range for each specific system.
The amount of the metal containing compound used
and the time of treatment can be varied to maximize the
selective enhancement treatment. With respect to iron
carbonyl the preferred amount employed is from about
0.1 to about 100 kilograms per metric ton offeed, more
preferably from about 1 to about 50 kilograms per metric
ton of feed, and most preferably from about 2 to 20
kilograms per metric ton of feed. The reaction is generally
conducted for a period of time from about 0.05 to
about 4 hours, more preferably from about 0.15 to about
2 hours, and most preferably from about 0.25 to 1 hour.
The process of this invention is not especially useful
in beneficiating oxide ores which are highly naturally
magnetic since such ores can be beneficiated by subjecting
them to a magnetic separation process or first heating
them before the magnetic process. An example of
such an ore is pyrolusite.
After the feed mixture containing the metal oxide
values has been pretreated with heat and treated with a
metal containing compound, it can then be subjected to
a physical separation process to effect the separation of
the treated metal oxides from the gangue. Any of many
commercially available magnetic separators can be used
to remove these values from the gangue. For example,
low or medium intensity separations can be made with
a permanent magnetic drum separator, electromagnetic
drum separators, induced roll separators or other configurations
known to those skilled in the art. Since most
oxides are liberated at a mesh size of 65 mesh or fmer, a
wet magnetic separation process is more effective.
Thus, high intensity, high gradient wet magnetic separators
are preferred. Also, electrostatic techniques may
be employed as the primary separation means, or in
addition to the magnetic separation means. The selective
change in surface characteristics changes the electrical
conductivity of the particle in analogous fashion
to changing the particle's magnetic characteristics. Additionally,
due to the fact that the oxide surface characteristics
have been selectively altered, the oxides are
often more amenable to processes such as flotation and
chemical leaching.
EXAMPLE I
Samples of different minerals were ground to a minus
65 mesh and mixed with minus 65 mesh silica sand to
produce 3% synthetic ores with the exception of carnotite
which was a 5% ore. Each sample was pretreated
with steam by rapidly heating the sample to 200° C.
under a nitrogen purge; thereafter the sample was
treated for 15 minutes with 200 kilograms of steam per
metric ton of sample. The reactor· was then cooled
under a nitrogen purge. Following this steam pretreatment
each sample was treated with 8 kilograms of iron
pentacarbonyl per metric ton of sample for 30 minutes
at the temperature indicated in Table l. All of the samples
were then subjected to a magnetic separation process.
The results are given in Table l.
TABLE 1
Temperature
Of Fe(CO)s Weight Grade Metal
Mineral J'reatment ('C.) Product (%) (%) Metal Distribution
Carnotite 145 Magnetic 24.0 0.059 U30g 70.0
Nonmagnetic 76.0 0.008 U30g 30.0
Calculated Feed 100.0 0.020 U30 g 100.0
Apatite 125 Magnetic 1.6 8.14 P 36.0
7
TABLE I-continued
4,205,979
8
Temperature
Of Fe(CO)s
Mineral Treatment ("C.) Product
Nonmagnetic
Calculated Feed
Scheelite 135 Magnetic
Nonmagnetic
Calculated Feed
Cuprite 125 Magnetic
Nonmagnetic
Calculated Feed
Cassiterite 128 Magnetic
Nonmagnetic
Calculated Feed
Weight Grade Metal
(%) (%) Metal Distribution
98.4 0.235 P 64.0
100.0 0.36 P 100.0
1.55 6.01 W 23.4
98.45 0.31 W 76.6
100.0 0.40 W 100.0
1.9 45.1 Cu 71.8
98.1 0.344 Cu 28.2
100.0 1.19 Cu 100.0
14.5 2.06 Sn 23.5
85.5 1.14 Sn 76.5
100.0 1.27 Sn 100.0
were then subjected to a wet magnetic separation process.
The results are presented in Table 3.
TABLE 3
Te'!'perature
of Fe(CO)s Weight Grade Metal
Mineral Treatment ("C.) Product (%) (%) Metal Distribution
Carnotite 145 Magnetic 62.5 0.047 U30s 90.7
Nonmagnetic 37.5 0.008 U30a 9.3
Calculated Feed 100.0 0.032 UJOa 100.0
Apatite 125 Magnetic 1.9 7.96 P 39.7
Nonmagnetic 98.1 0.234 P 60.3
Calculated Feed 100.0 0.38 P 100.0
Scheelite 135 Magnetic 4.4 4042 W 51.7
Nonmagnetic 95.6 0.19 W 48.3
Calculated Feed 100.0 0.38 W 100.0
Cuprite 125 Magnetic 2.9 32.6 Cu 75.3
Nonmagnetic 97.1 0.32 Cu 24.7
Calculated Feed 100.0 1.26 Cu 100.0
EXAMPLE 2
For comparison, additional samples of the same type
of ores of Example 1 were subjected to just a steam 35 EXAMPLE 4
pretreatment, and then magnetically separated. Analyses
of these comparative blanks are given in Table 2. For comparative purposes, additional samples ofthe
same type of ores of Example 3 were subjected to just
TABLE 2 the heat and nitrogen pretreatment, and then magneti-
Metal
40
cally separated. Analyses of these comparative blankS
Weight Grade Distri- are given in Table 4.
Mineral Product (%) (%) Metal bution
Carnotite Magnetic 0.71 0.321 U30S 12.6 Table 4
Nonmagnetic 99.29 0.016 U30 S 87.4 Metal
Calculated Feed 100.0 0.018 U30S 100.0 Weight Grade Distri-
Apatite Magnetic 0.48 0.518 P 0.62 45 Mineral Product (%) (%) Metal butiqil
Nonmagnetic 99.52 0.399 P 99.38 Carnotite Magnetic 1.1 0.421 U30s 20.6
Calculated Feed 100.0 0.40 P 100.00 Nonmagnetic 98.9 O.oI8 U30a 79.4
Scheelite Magnetic 1.25 1.00 W 3.1 Calculated Feed 100.0 0.022 U30S 100.0
Nonmagnetic 98.75 0.40 W 96.9 Apatite Magnetic 0.94 0.683 P 1.8
Calculated Feed 100.0 0.41 W 100.0 Nonmagnetic 99.06 0.358 P 98.2
Cuprite Magnetic 1.04 42.3 Cu 37.9
50 Calculated Feed 100.0 0.36 P 100.0
Nonmagnetic 98.96 0.728 Cu 62.1 Scheelite Magnetic I.4 0.82 W 2.&
Calculated Feed 100.0 1.16 Cu 100.0 Nonmagnetic 98.6 0.40 W 97.2
Cassiterite Magnetic 0.97 24.0 Sn 19.5 Calculated Feed 100.0 0.41 W 100.0
Nonmagnetic 99.03 0.97 Sn SO.5 Cuprite Magnetic 0.76 34.1 Cu 26.6
Calculated Feed 100.0 1.19 Sn 100.0 Nonmagnetic 99.24 0.72 Cu 73.4
5S Calculated Feed 100.0 0.97 Cu 100.0
EXAMPLE 3
Samples of different synthetic ores were prepared as
indicated in Example 1. Each of the samples in this
example was pretreated with heat and nitrogen by rapidly
heating a reactor containing the sample to 400° C. 60
during a nitrogen purge which flowed at a rate such
that one reactor volume of gas was introduced into the
system every 4.3 minutes and maintaining these conditions
for 15 minutes. Then the reactor was cooled under
a nitrogen purge. Following this pretreatment each 6S
sample was treated with 8 kilograms of iron pentacarbonyl
per metric ton of sample for 30 minutes at the
temperature indicated in Table 3. All of the samples
EXAMPLE 5
Samples of different synthetic ores were prepared as
indicated in Example 1. Each of the samples in this
example was pretreated with heat and hydrogen by
rapidly heating the reactor containing the sample to
400° C. while purging it with nitrogen. This temperature
was maintained for 15 minutes while hydrogen gas
was passed through the reactor at a flow rate of one
reactor volume of gas every 4.3 minutes. The reactor
was cooled under a purge of nitrogen gas. Each sample
was then treated with 8 kilograms of iron pentacarbonyl
4,205,979
9
per metric ton of sample for 30 minutes at the temperature
indicated in Table 5. Thereafter the samples were
subjected to a wet magnetic separation process. The
10
minutes at the temperature indicated in Table 7. The
samples were then subjected to a wet magnetic separation
process. The results are presented in Table 7.
TABLE 7
Temperature
of Fe(CO)s Weight Grade Metal
Mineral Treatment ("C.) Product (%) (%) Metal Distribution
Carnotite 145 Magnetic 54.7 0.051 U30 S 93.9
Nonmagnetic 45.3 0.004 U30S 6.1
Calculated Feed 100.0 0.030 U30S 100.0
Scheelite 135 Magnetic 5.0 4.20 W 53.8
Nonmagnetic 95.0 0.19 w 46.2
Calculated Feed 100.0 0.39 W 100.0
Cuprite 125 Magnetic 4.8 23.4 Cu 87.4
Nonmagnetic 95.2 0.17 Cu 12.6
Calculated Feed 100.0 \.29 Cu 100.0
results are given in Table 5.
TABLE5
Temperature
of Fe(CO)s Weight Grade Metal
Mineral Treatment ("C.) Product (%) (%) Metal Distribution
Carnotite 145 Magnetic 63.7 0.057 U30S 96.2
Nonmagnetic 36.3 0.004 U30S 3.8
Calculated Feed 100.0 0.038 U30S 100.0
Apatite 125 Magnetic 3.3 5.75 P 57.0
Nonmagnetic 96.7 0.148 P 43.0
Calculated Feed 100.0 0.33 P 100.0
Cuprite 125 Magnetic 3.1 3\.2 Cu 8\.4
Nonmagnetic 96.9 0.228 Cu 18.6
Calculated Feed 100.0 1.19 Cu 100.0
EXAMPLE 6
For comparative purposes, additional samples of the
same type of ores of Example 5 were subjected to just
the heat and hydrogen pretreatment, and then magneti- 40
cally separated.. Analyses ofthese comparative blanks
are given in Table 6,
EXAMPLE 8
For comparative purposes, additional samples of the
same type of ores of Example 7 were subjected to just
the heat and carbon monoxide pretreatment, and then
magnetically separated. Analyses of these comparative
blanks are given in Table 8.
TABLE8
TABLE 6
Metal
Weight Grade Distri- 45 Mineral
Mineral Product (%) (%) Metal bution Carnotite
Carnotite Magnetic 10.1 0.209 U30S 85.4
Nonmagnetic 89.9 0.004 U30S 14.6
Calculated Feed 100.0 0.025 U30S 100.0 Scheelite
Apatite Magnetic 2.2 2.91 P 16.5 Nonmagnetic 97.8 0.332 P 83.5 50
Calculated Feed 100.0 0.39 P 100.0 Cuprite
Cuprite Magnetic 0.73 44.1 Cu 34.3
Nonmagnetic 99.27 0.622 Cu 65.7
Calculated Feed 100.0 0.94 Cu 100.0
Metal
Weight Grade Distri-
Product (%) (%) Metal bution
Magnetic 8.4 0.248 U30S 85.0
Nonmagnetic 9\.6 0.004 U30S 15.0
Calculated Feed 100.0 0.024 U30S 100.0
Magnetic 2.4 0.85 W 5.0
Nonmagnetic 97.6 0.40 W 95.0
Calculated Feed 100.0 0.41 W 100.0
Magnetic 0.95 34.3 Cu 26.7
Nonmagnetic 99.05 0.904 Cu ') 73.3
Calculated Feed 100.0 \.22 Cu 100.0
55
EXAMPLE 7
Samples of different synthetic ores were prepared as
indicated in Example 1. Each of the samples in this
example was pretreated with heat and carbon monoxide 60
by rapidly heating the reactor containing the sample to
400° C. while purging it with nitrogen. This temperature
was maintained for 15 minutes while carbon monoxide
gas was passed through the reactor at a flow rate
of one reactor volume of gas every 4.3 minutes. The 65
reactor was cooled under a purge of nitrogen gas.
Thereafter each sample was treated with 8 kilograms of
iron pentacarbonyl per metric ton of sample for 30
EXAMPLE 9
For comparative purposes, samples of the same type
of ores used in the preceding examples were not given
any pretreatment but were just treated with 8 kilograms
of iron pentacarbonyl per metric ton of feed for 30
minutes at the same temperature as used in the preceding
examples. These samples were then magnetically
separated. Additionally, another series of samples of
ores were treated merely to the temperature of the iron
carbonyl treatment and given no iron carbonyl treatment;
these were also subjected to a magnetic separation
process. Analyses of these comparative results are
given below in Table 9.
4,205,979
11 12
TABLE 9
Dosage of
Fe(CO)s Weight Grade Metal
Mineral (Kg./nr; ton) Product (%) (%) Metal Distribution
Carnotite 8 Magnetic 1.4 0.731 U30S 35.3
Nonmagnetic 98.6 0.019 U30S 64.7
Calculated Feed 100.0 0.029 U30S 100.0
Carnotite 0 Magnetic 0.67 0.297 U30S 6.7
Nonmagnetic 99.33 0.028 U30S 93.3
Calculated Feed 100.0 0.030 U30S 100.0
Apatite 8 Magnetic 4.9 4.0 P 39.9
Nonmagnetic 95.1 0.31 P 60.1
Calculated Feed 100.0 0.491 P 100.0
Apatite 0 Magnetic 0.41 0.34 P 0.4
Nonmagnetic 99.59 0.36 P 99.6
Calculated Feed 100.0 0.36 P 100.0
Scheelite 8 Magnetic 27.4 2.85 W 58.6
Nonmagnetic 72.6 0.76 W 41.4
Calculated Feed 100.0 1.33 W 100.0
Scheelite 0 Magnetic 2.1 2.44 W 4.0
Nonmagnetic 97.9 1.23 W 96.0
Calculated Feed 100.0 1.25 W 100.0
Cuprite 8 Magnetic 2.1 0.165 Cu 47.3
Nonmagnetic 97.9 0.004 Cu 52.7
Calculated Feed 100.0 0.0074 Cu 100.0
Cuprite 0 Magnetic 0.54 0.417 Cu 31.5
Nonmagnetic 99.46 0.005 Cu 68.5
Calculated Feed 100.0 0.0073 Cu 100.0
Bauxite Magnetic 3.3 20.1 AI 97.9
Nonmagnetic 96.7 0.014 AI 2.1
Calculated Feed 100.0 0.677 AI 100.0
Bauxite 0 Magnetic 0.81 17.0 AI 18.7
Nonmagnetic 99.19 0.605 AI 81.3
Calculated Feed 100.0 0.738 AI 100.0
Hematite 8 Magnetic 1.14 36.2 Fe 33.9
Nonmagnetic 98.86 0.81 Fe 66.1
Calculated Feed 100.0 1.21 Fe 100.0
Hematite 0 Magnetic 0.10 22.9 Fe 3.1
Nonmagnetic 99.90 0.73 Fe 96.9
Calculated Feed 100.0 0.75 Fe 100.0
Cassiterite 8 Magnetic 3.5 4.83 Sn 14.9
Nonmagnetic 96.5 0.998 Sn 85.1
Calculated Feed 100.0 1.13 Sn 100.0
Cassiterite 0 Magnetic 0.65 23.6 Sn 10.8
Nonmagnetic 99.35 U5 Sn 89.2
Calculated Feed 100.0 1.39 Sn 100.0
EXAMPLE 10
Samples of apatite and bauxite were made into 3%
synthetic ores as indicated in Example 1. Each of these
samples was subjected to a pretreatment and thereafter
treated with 16 kilograms offerrocene per metric ton of 4S
sample. The ferrocene were mixed with the sample, and
the temperature of the reactor was slowly raised to 400·
C. over a two hour period. The system was purged with
nitrogen prior to and following the ferrocene treatment.
Finally, the samples were subjected to a wet magnetic SO
separation process. Each of the pretreatments, i.e.,
steam, heat plus nitrogen, heat plus hydrogen and heat
plus carbon monoxide, were conducted in the same
manner as the pretreatment in Examples 1,3, S, and 7,
respectively.
For comparative purposes, additional samples of the
same type of ores were subjected to just the pretreatment
followed by wet magnetic separation. Also, samples
of these ores were given no pretreatment and were
subjected to only the ferrocene treatment with subsequent
magnetic separation. Analyses of these comparative
samples are given in Table 10.
TABLE 10
Weight Grade Metal
Mineral Pretreatment Product (%) (%) Metal Distribution
Apatite Steam Magnetic 0.91 3.33 P 5.7
Nonmagnetic 99.09 0.502 P 94.3
Calculated Feed 100.0 0.53 P 100.0
Apatite Steam blank Magnetic 0.37 1.16 P 0.8
Nonmagnetic 99.63 0.53 P 99.2
Calculated Feed 100.0 0.53 P 100.0
Apatite Heat &; N2 Magnetic 0.96 3.99 P 7.2
Nonmagnetic 99.04 0.50 P 92.8
Calculated Feed 100.0 0.53 P 100.0
Apatite Heat &; N2 blank Magnetic 0.60 1.64 P 1.8
Nonmagnetic 99.40 0.53 P 98.2
Calculated Feed 100.0 0.54 P 100.0
Apatite Heat &; H2 Magnetic 1.7 4.71 P 15.0
Nonmagnetic 98.3 0.46 P 85.0
Calculated Feed 100.0 0.53 P 100.0
Apatite Heat &; H2 blank Magnetic 1.3 4.81 P 11.9
4,205,979
13 14
TABLE to-continued
Weight Grade Metal
Mineral Pretreatment Product (%) (%) Metal Distribution
Nonmagnetic 98.7 0.47 P 88.1
Calculated Feed 100.0 0.53 P 100.0
Apatite Heat&CO Magnetic 1.1 5.71 P 12.4
Nonmagnetic 98.9 0.45 P 87.6
Calculated Feed 100.0 0.51 P 100.0
Apatite Heat & CO blank Magnetic 0.77 6.40 P 9.2
Nonmagnetic 99.23 0.49 P 90.8
Calculated Feed 100.0 0.54 P 100.0
Apatite None Magnetic 5.1 2.1 P 26.1
(Ferrocene Nonmagnetic 94.9 0.32 P 73.9
treatment Calculated Feed 100.0 0.41 P 100.0
@400' c.)
Apatite None Magnetic 0.54 1.22 P 1.6
(Heat to Nonmagnetic 99.46 0.43 P 98.4
400' C. and Calculated Feed 100.0. 0.435 P 100.0
no Ferrocene)
Bauxite Steam Magnetic 2.8 23.1 Al 94.3
Nonmagnetic 97.2 0.04 Al 5.7
Calculated Feed 100.0 0.69 Al 100.0
Bauxite Steam blank Magnetic 1.33 1.71 Al 3.8
Nonmagnetic 98.67 0.59 Al 96.2
Calculated Feed 100.0 0.61 Al 100.0·
Bauxite Heat & Nz Magnetic 3.4 21.0 Al 77.9
Nonmagnetic 96.6 0.21 Al 22.1
Calculated Feed 100.0 0.92 Al 100.0
Bauxite Heat & Nz Magnetic 2.0 25.6 AI 61.3
blank Nonmagnetic 98.0 0.33 Al 38.7
Calculated Feed 100.0 0.84 Al 100.0
Bauxite Heat & Hz Magnetic 4.1 18.8 AI 86.1
Nonmagnetic 95.9 0.13 AI 13.9
Calculated Feed 100.0 0.90 Al 100.0
Bauxite Heat & Hz Magnetic 3.3 17.6 AI 77.9
blank Nonmagnetic 96.7 0.17 Al 22.1
Calculated Feed 100.0 0.75 Al 100.0
Bauxite Heat & CO Magnetic 1.8 17.3 Al 66.5
Nonmagnetic 98.2 0.16 Al 33.5
Calculated Feed 100.0 0.47 Al 100.0
Bauxite Heat & CO Magnetic 3.0 23.4 Al 75.1
blank Nonmagnetic 97.0 0.24 Al 24.9
Calculated Feed 100.0 0.93 Al 100.0
Bauxite None Magnetic 3.4 14.3 Al 86.3
(Ferrocene Nonmagnetic 96.6 0.08 AI 13.7
treatment Calculated Feed 100.0 0.563 AI 100.0
@400' c.)
None
Bauxite (Heated to Magnetic 2.4 17.7 Al 64.5
400' C. and Nonmagnetic 97.6 0.24 Al 35.5
no ferrocene) Calculated Feed 100.0 0.659 Al 100.0
EXAMPLE II 45 ments indicated in Table II were conducted in the same
manner as described in Example 1, 3, 5 or 7.
Samples of different synthetic ores were prepared as For comparative purposes, samples of the same type
indicated in Example 1. Each of these samples were of ores were subjected to just the pretreatment followed
subjected to a pretreatment and thereafter treated with by magnetic separation (these results are designated as
16 kilograms of vaporized ferric acetylacetonate per 50 blanks in Table 11). Additional samples of these ores
metric ton of sample at a temperature of 2700 C. for a were given no pretreatment and were subjected to only
period of 30 minutes. The samples were then subjected the ferric acetylacetonate treatment with subsequent
to a magnetic separation process. Each of the pretreat- magnetic separation. Analyses of these comparative
samples are given below in Table 11.
TABLE 11
Weight Grade Metal
Mineral Pretreatment Product (%) (%) Metal Distribution
Carnotite Steam Magnetic 4.1 0.089 U308 48.8
Nonmagnetic 95.9 0.004 U308 51.2
Calculated Feed 100.0 0.007 U308 100.0
Carnotite Steam Magnetic 0.52 0.092 U308 3.1
blank Nonmagnetic 99.48 O.oJ5 U308 96.9
Calculated Feed 100.0 O.oJ5 U308 100.0
Carnotite Heat & Hz Magnetic 4.1 0.122 U308 63.5
Nonmagnetic 95.9 0.003 U308 36.5
Calculated Feed 100.0 0.008 U30 8 100.0
Carnotite Heat & Hz Magnetic 6.7 0.106 U308 60.4
blank Nonmagnetic 93.3 0.005 U308 39.6
Calculated Feed 100.0 0.012 U308 100.0
Carnotite Heat & CO Magnetic 7.7 0.093 U308 79.5
15
4,205,979
16
TABLE II-continued
Weight Grade Metal
Mineral Pretreatment Product (%) (%) Metal Distribution
Nonmagnetic 92.3 0.002 U30 g 20.5
Calculated Feed 100.0 0.009 U30 g 100.0
Carnotite Heat &CO Magnetic 5.1 0.115 U30 g 46.9
blank Nonmagnetic 94.9 0.007 U30g 53.1
Calculated Feed 100.0 0.013 U30g 100.0
Carnotite None (ace- Magnetic 1.2 0.418 U30 g 25.6
tylaceto- Nonmagnetic 98.8 0.015 U30g 74.4
nate at 270· C.) Calculated Feed 100.0 0.020 U30 g 100.0
Carnotite None (heated Magnetic 0.97 0.514 U30g 21.9
to 270· C.) Nonmagnetic 99.03 0.Ql8 U30 g 78.1
Calculated Feed 100.0 0.023 U30 g 100.0
Apatite Heat & H2 Magnetic 3.2 2.15 P 13.0
Nonmagnetic 96.8 0.475 P 87.0
Calculated Feed 100.0 0.53 P 100.0
Apatite Heat & H2 Magnetic 1.3 4.81 P 11.9
blank Nonmagnetic 98.7 0.47 P 88.1
Calculated Feed 100.0 0.53 P 100.0
Apatite Heat & CO Magnetic 3.0 2.20 P 12.8
Nonmagnetic 97.0 0.464 P 87.2
Calculated Feed 100.0 0.52 P 100.0
Apatite Heat & CO Magnetic 0.77 6.40 P 9.2
blank Nonmagnetic 99.23 0.49 P 90.8
Calculated Feed 100.0 0.54 P 100.0
Apatite None (acetyl- Magnetic 2.3 0.96 P 5.8
acetonate at Nonmagnetic 97.7 0.37 P 94.2
2W c.) Calculated Feed 100.0 0.384 P 100.0
Apatite None (heated Magnetic 0.34 0.637 P 0.5
to 270· C.) Nonmagnetic 99.66 0.427 P 99.5
Calculated Feed 100.0 0.428 P 100.0
Hematite Steam Magnetic 0.62 29.8 Fe 20.1
Nonmagnetic 99.38 0.739 Fe 79.9
Calculated Feed 100.0 0.92 Fe 100.0
Hematite Steam Magnetic 0.06 17.6 Fe 1.0
blank Nonmagnetic 99.94 1.03 Fe 99.0
Calculated Feed 100.0 1.04 Fe 100.0
Hematite Heat & N2 Magnetic 0.70 26.0 Fe 19.6
Nonmagnetic 99.30 0.75 Fe 80.4
Calculated Feed 100.0 0.93 Fe 100.0
Hematite Heat & N2 Magnetic 0.05 23.4 Fe \.I
blank Nonmagnetic 99.95 1.05 Fe 98.9
Calculated Feed 100.0 1.06 Fe 100.0
Hematite Heat & H2 Magnetic 4.6 8.88 Fe 67.1
Nonmagnetic 95.4 0.21 Fe 32.9
Calculated Feed 100.0 0.61 Fe 100.0
Hematite Heat & H2 Magnetic 6.8 6.85 Fe 74.6
blank Nonmagnetic 93.2 0.17 Fe 25.4
Calculated Feed 100.0 0.62 Fe 100.0
Hematite None (acetyl- Magnetic 0.63 24.1 Fe 16.9
acetonate at Nonmagnetic 99.37 0.75 Fe 83.1
270· c.) Calculated Feed 100.0 0.90 Fe 100.0
Hematite None (heated Magnetic 0.39 5.96 Fe 2.4
to 270· C.) Nonmagnetic 99.61 0.94 Fe 97.6
Calculated Feed 100.0 0.96 Fe 100.0
Bauxite Steam Magnetic 4.3 13.3 AI 81.0
Nonmagnetic 95.7 0.14 AI 19.0
Calculated Feed 100.0 0.71 AI 100.0
Bauxite Steam Magnetic \.16 1\.1 Al 18.3
blank Nonmagnetic 98.84 0.58 AI 81.7
Calculated Feed 100.0 0.70 Al 100.0
Bauxite Heat & N2 Magnetic 2.5 20.8 Al 80.4
Nonmagnetic 97.5 0.13 AI 19.6
Calculated Feed 100.0 0.65 AI 100.0
Bauxite Heat & N2 Magnetic 1.88 17.9 AI 50.2
blank Nonmagnetic 98.12 0.34 Al 49.8
Calculated Feed 100.0 0.67 Al 100.0
Bauxite None (acetyl- Magnetic 2.4 18.9 Al 70.0
acetonate at Nonmagnetic 97.6 0.20 AI 30.0
270· c.) Calculated Feed 100.0 0.649 AI 100.0
Bauxite None (heated Magnetic 1.6 24.4 Al 48.0
to 270· C.) Nonmagnetic 98.4 0.43 AI 52.0
Calculated Feed 100.0 0.814 Al 100.0
Scheelite Steam Magnetic 4.4 1.07 W 10.1
Nonmagnetic 95.6 0.44 W 89.9
Calcul~ted Feed 100.0 0.47 W 100.0
Scheelite Steam Magnetic 1.2 \.29 W 3.1
blank Nonmagnetic 98.2 0.49 W 96.9
Calculated Feed 100.0 0.50 W 100.0
Scheelite Heat & CO Magnetic 4.5 0.936 W 8.6
Nonmagnetic 95.5 0.466 W 9\.4
Calculated Feed 100.0 0.49 W 100.0
-
17
4,20S,979
18
TABLE II-continued
Weiaht Orade Metal
Mineral Pretreatment Product (%) (%) Metal Dlatributian
Scheellte Heat ot CO Maanetie 1.9 1.55 W 5.9
blank Nanmaanetle 98.1 0.48 W 94.1
Caleulated Peed 100.0 0.50 W 100.0
ScheeUte Heat ot N2 Maanetie 3.8 1.25 W 9.8
Nanmaanetle 96.2 0.454 W 90.2
Caleulated Peed 100.0 0.48 W 100.0
ScheeUte Heat" N2 Maanetle 1.8 1.16 W 4.2
blank Nanmaanetie 98.2 0.49 W 95.8
Caleulated Peed 100.0 0.50 W 100.0
Scheellte Nane (I"etyl. Maanetie 3.1 0.96 W 7.7
I"etanate at Nanmaanetie 96.9 0.37 W 92.3
270' C.) Caleulated Peed 100.0 0.39 W 100.0
ScheeUte None (heated Maanetie 1.3 1.09 W 3.3
to 270' C.) Nanmaanetle 98.7 0.42 W 96.7
Caleulated Peed 100.0 0.43 W 100.0
EXAMPLE 12 EXAMPLE 13
Samples of carnotite and cuprite synthetic ores were 20 Samples of carnotite and cuprite synthetic ores were
prepared as indicated in Example 1.'AIIII1ple ofeach of prepared II indicated in Example 1. Asample ofeach of
these ores wu pretreated with heat and hydrolen suI- these ores WII pretreated with heat and sulfur dioxide
fide III, by rapidly heatinl the reactor containinl the IU by rapidly heatinl the reactor containinl the sample
sample to 200' C. while purlinl it with nitrolen. This 25 to 400' C. while purlinl it with nitrolen. This tempera·
temperature wu maintained for 15 minutes while hy. ture WII maintained for 15 minutes while sulfur dioxide
drogen sulfide III WII pused throulh,the reactor at a III WII passed throulh the reactor at a flow rate of one
flow rate ofone reactor volume of las beinl introduced reactor volume of III beinl introduced every 4.3 min·
into the system every 4.3 minutes. The reactor WII utes. the reactor WII cooled under a purle of nitrolen
cooled under a purle of nitrolen las. Each sample WII III. Each sample WII then treated with 8 kilolrams of
then treated with 8kilograms of iron pentacarbonyl per 30 iron pentacarbonyl per metric ton of sample for 30,
metric ton of sample for 30 minutes at a temperature of minutes at a temperature of 145' C. in the case of the
145' C. in the case of carnotite and at a temperature of carnotite ore and a temperature of 125' C. in the case of
125' C. in the case of cuprite ore. For comparative the cuprite ore. For comparative purposes, an addi·
purposes, an additional sample of each of these ores tionahample oreach ofthese ores wilsubjected only to
received merely the pretreatment in the manner indio 35 the pretreatment in the manner indicated above. All of
cated above. All of the samples were subjected to a wet the IIII1ples were subjected to a wet mqnetic separa·
magnetic separation process. Analyses of the products tion proceu and the analyses of the products thus ob·
thus obtained are presented below in Table 12. tained are given below in Table 13.
TABLE 12
Minerai
Clmotlte
Clmatlte
Cuprite
Cuprite
Pe (CO)s
Treltment
Yea
No
Yea
No
Produet
Mlanetle
Nonmlanetle
Clleullted Peed
Mlanetle
Nonmlanetie
Clleullted Peed
Mlanetle
Nonmllnetle
Clleullted Peed
Mlanetle
Nonmllnetle
Clleulltllll PHd
Weiaht Oracle
("') ("') Metll
43.8 0,024 U30.
56.2 0,00I U30.
100,0 0.011 U30.
0.86 0,187 U30.
99.14 0.008 U30.
100.0 0.010 U30.
10,3 5.08 Cu
89,7 0,89 Cu
100,0 1.32 Cu
0,77 12.1 Cu
99.23 0.40 Cu
100,0 0.49 Cu
Metll
Dlltrlbutlan
94,9
5.1
100.0
16,9
83,1
100.0
39.6
60,4
100.0
19.0
81.0
100,0
TABLE 13
Pe (CO)S Weilht Oracle Melli
Minerll Tl'Illlmenl Product ("') ("') MellI Diltrlbutlon
CArnotlle Ye~ Mllnetle 59.2 0,019 U30. 82,1
Nllnmllnetle 40,8 0.006 U30. 17.9
ClleulllllI Piled 100.0 0.014 U30i 100,0
Clrnolitll No ,Mlllnlltle Cl.99 0,161 U30. 10,3
Nonmllnelle 99.01 ' 0,014 U30. 89.7
CAleulllllI PHd 100.0 0.015 U30. 100.0
CUllrl11l YIlI Mlllnlltle 32.8 1.21 Cu 47.2
Nllnmlllnlllle 67.2 0,66 Cu 52.8
Cileullilld'PIllld 100,0 0,84 Cu 100.0
CUllrlllJ Nil Millnelie (>.33 9.35 Cu 3.9
Nllnmillnetie 99.67 0,77 Cu 96.1
Clteutlled Pelll 100,0 0.10 Cu 100,0
4,205,979
19
EXAMPLE 14
Samples of carnotite and cuprite synthetic ores were
prepared as indicated in Example 1. A sample of each of
these ores was pretreated with heat and ammonia by
rapidly heating the reactor containing the sample to
4000 C. while purging it with nitrogen. This temperature
was maintained for 15 minutes while ammonia gas
was passed through the reactor at a flow rate of one
reactor volume of gas being introduced every 4.3 min-
20
perature variations. The temperature and time of the
pretreatment are set forth in Table 15. For comparative
purposes, samples were subjected just to the pretreatment,
receiving no iron carbonyl treatment. Addition-
S ally, two samples received no pretreatment with one
beitlg subjected to the iron carbonyl treatment and the
other merely being heated to a temperature of 1450 C.
All of the samples were subjected to a wet magnetic
separation process. Analyses of the products thus ob-
10 tained are presented below in Table 15.
TABLE 15
FE (CO)s Pretreatment
Treatment Temperature Time Weight Grade UJOg
(Pretreatment) ("C.) (minutes) Product (%) (%) Distribution
Yes ISO 15 Magnetic 22.7 0.024 58.5
(Heat &. H2) Nonmagnetic 77.3 0.005 41.5
Calculated Feed 100.0 0.009 100.0
No ISO 15 Magnetic 0.92 0.033 3.0
(Heat &. H2) Nonmagnetic 99.08 0.010 97.0
Calculated Feed 100.0 0.010 100.0
Yes ISO 90 Magnetic 11.1 0.033 37.0
(Heat &. H2) Nonmagnetic 88.9 0.007 62.9
Calculated Feed 100.0 0.010 100.0
No ISO 90 Magnetic 0.73 0.061 3.1
(Heat &. H2) Nonmagnetic 99.27 0.014 96.9
Calculated Feed 100.0 0.014 100.0
Yes ISO 15 Magnetic 52.0 0.017 78.6
(Heat&. CO) Nonmagnetic 48.0 0.005 21.4
Calculated Feed 100.0 0.011 100.0
No 150 15 Magnetic 0.78 0.226 15.1
(Heat &. CO) Nonmagnetic 99.22 0.010 84.9
Calculated Feed 100.0 0.012 100.0
Yes none Magnetic \.4 0.73 34.5
Nonmagnetic 98.6 0.019 65.5
Calculated Feed 100.0 0.029 100.0
No (heated none Magnetic 0.67 0.297 6.7
to 145' C.) Nonmagnetic 99.33 0.028 93.3
Calculated Feed 100.0 0.030 100.0
utes. The reactor was cooled under a purge of nitrogen
gas. Each sample was then treated with 8 kilograms of
iron pentacarbonyl per metric ton of sample for 30
minutes at a temperature of 1450 C. in the case of the
carnotite ore and at a temperature of 1250 C. in the case 40
of the cuprite ore. All of the samples were subjected to
a wet magnetic separation process. The analyses of the
products thus obtained are presented below in Table 14.
TABLE 14
EXAMPLE 16
Chrysocolla was ground to a minus 65 mesh and
mixed with minus 65 mesh silica sand to produce a 3%
synthetic ore. A sample of this ore was pretreated with
steam in the manner described in Example 1 and another
sample was pretreated with heat and hydrogen
sulfide gas in the manner described in Example 12. Both
were then separately treated with 8 kilograms of iron
Fe (CO)s Weight Grade Metal
Mineral Treatment Product (%) (%) Metal Distribution
Carnotite Yes Magnetic 49.3 0.019 UJOg 82.2
Nonmagnetic SO.7 0.004 UJOg 17.8
Calculated Feed 100.0 0.011 UJOg 100.0
Carnotite No •Magnetic \.9 0.140 U30g 2\.3
Nonmagnetic 98.1 0.010 U30 g 78.7
Calculated Feed 100.0 0.012 U30g 100.0
Cuprite Yes Magnetic 5.6 20.6 Cu 91.S
Nonmagnetic 94,4 0.114 Cu 8.5
Calculated Feed 100.0 \.26 Cu 100.0
Cuprite No Magnetic \.6 42.9 Cu 59.7
Nonmagnetic 98.4 0.47 Cu 40.3
Calculated Feed 100.0 1.15 Cu 100.0
Samples of carnotite were made into 3% synthetic
ores as indicated in Example 1. Each of these samples
was subjected to a pretreatment and thereafter treated
with eight kilograms of iron pentacarbonyl per metric 65
ton of sample for thirty minutes at a temperature of 1350
C. The pretreatments were carried out as described in
Examples 5 and 7 with the exception of time and tem-
EXAMPLE 15 60
pentacarbonyl per metric ton of ore for 30 minutes at a
temperature of 1600 C.
For comparative purposes, additional samples of the
ore were subjected to only the steam and hydrogen
sulfide pretreatments. Also, two sets of samples of the
ore were given no pretreatment; one was subjected to
only the iron pentacarbonyl treatment and the other
sample was heated to 1600 C.
4,205,979
21
All of the samples were subjected to a wet magnetic
separation process. Anaylses of the products thus obtained
are given below in Table 16.
22
7. The process of claim 6 wherein the metal containing
compound is employed in an amount of from about
0.1 to 100 kilograms per metric ton of ore.
TABLE 16
Weight Grade Copper Separation
Pretreatment Product (%) (%) Distribution Amperage
None (Fe(DOls Magnetic 5.6 3.55 91.3 2.0
at 160' C.) Nonmagnetic 94.4 0.02 8.7
Calculated Feed 100.0 0.218 100.0
None (heated Magnetic 1.44 6.86 50.1 2.0
to 16O'C.) Nonmagnetic 98.56 0.10 49.9
Calculated Feed 100.0 0.197 100.0
Steam Magnetic 4.7 3.66 72.1 1.0
Nonmagnetic 95.3 0.07 27.9
Calculated Feed 100.0 0.239 100.0
Steam blank Magnetic 0.6 5.91 17.3 1.0
Nonmagnetic 99.4 0.17 82.7
Calculated Feed 100.0 0.204 100.0
H2S Magnetic 21.0 0.41 40.5 1.0
Nonmagnetic 79.0 0.16 59.5
Calculated Feed 100.0 0.213 100.0
H2S blank Magnetic 0.41 1.58 2.9 1.0
Nonmagnetic 99.59 0.22 97.1
Calculated Feed 100.0 0.226 100.0
None (Fe(COls Magnetic 3.5 5.11 78.8 1.0
at 160' C.) Nonmagnetic 96.5 0.05 21.2
Calculated Feed 100.0 0.227 100.0
None (heated to Magnetic 1.0 5.29 22.9 1.0
160' c.) Nonmagnetic 99.0 0.18 77.1
Calculated Feed 100.0 0.231 100.0
8. In a process for the beneficiation of a metal oxide
30 ore wherein the ore is treated with an iron carbonyl
compound under conditions which cause the iron carbonyl
compound to react substantially at the surface of
the metal oxide particles to the substantial exclusion of
the gangue particles so as to alter the surface characteristics
of the metal values thereby causing a selective
enhancement of the magnetic susceptibility of one or
more metal oxide values of the ore to the exclusion of
the gangue in order to permit a physical separation
between the values and the gangue, the improvement
comprising:
treating the ore with heat prior to its treatment with
the iron carbonyl.
9. The process of claim 8 wherein the ore is pretreated
to a temperature of at least about 800 C. for a
time period of at least about 0.1 hours.
10. The process of claim 9 wherein the ore is pretreated
to a temperature of from about 1250 C. to about
4500 C. for a time period of from about 0.20 to about 4
hours.
11. The process of claim 9 wherein the heat pretreatment
is conducted in the presence of a gas selected from
the group consisting of steam, nitrogen, hydrogen, carbon
monoxide, carbon dioxide, ammonia, hydrogen
sulfide, sulfur dioxide, methane, air, ethane, propane,
55 butane and other hydrocarbon compounds in the gaseous
state at the pretreatment temperature.
12. The process of claim 9 wherein the metal oxide
ore is selected from the group consisting of carnotite,
apatite, scheelite, cuprite, cassiterite, bauxite and hematite.
13. In a process for the beneficiation of a metal oxide
ore wherein the ore in a specific system is treated with
from about 0.1 to about 100 kilograms of a metal containing
compound per metric ton of ore at a temperature
within a range of 1250 C. less than the general
decomposition temperature of the metal containing
compound in a specific system for the ore being treated
for a period of time from about 0.05 to about 4 hours to
What is claimed is:
1. In a process for the beneficiation of a metal oxide
ore wherein the ore is treated with a metal containing
compound under conditions which cause the metal
containing compound to react substantially at the sur- 35
face of the metal oxide particles to the substantial exclusion
of the gangue particles so as to alter the surface
characteristics of the metal values thereby causing a
selective enhancement of the magnetic susceptibility of
one ore more metal oxide values of the ore to the exclu- 40
sion of the gangue in order to permit a separation between
the values and gangue, the improvement comprising:
treating the ore with heat prior to its treatment with
the metal containing compound. 45
2. The process of claim 1 wherein the heat pretreatment
is conducted at a temperature of at least about 800
C.
3. The process of claim 2 wherein the heat pretreatment
is conducted in the presence of a gas selected from 50
the group consisting of steam, nitrogen, hydrogen, carbon
monoxide, carbon dioxide, ammonia, hydrogen
sulfide, sulfur dioxide, methane, air, ethane, propane,
butane and other hydrocarbons in the gaseous state at
the pretreatment temperature.
4. The process of claim 3 wherein the gas is employed
in an amount of at least about 2 cubic meters per hour
per metric ton of metal oxide ore being processed.
5. The process of claim 3 wherein the gas is steam at
a temperature of at least about 1000 C. and employed in 60
an amount of from about I% to 50 weight percent water,
based on the weight of the metal oxide ore.
6. The process of claim 2 or claim 3 wherein the
treatment of the ore with the metal containing compound
is conducted at a temperature within a range of 65
1250 C. less than the general decomposition temperature
of the metal containing compound in a specific system
for the are being treated.
4,205,979
24
from about 2 to about 20 kilograms of an iron cOlltaining
compound per metric ton of ore at a temperature within
a range of 1250 C. less than the general decomposition
temperature of the iron containing compound in a specific
system for the ore being treated to cause the iron
containing compound to react substantially at the surface
of the metal oxide particles to the substantial exclusion
of the gangue particles so as to alter the surface
characteristics of the metal values thereby causing a
selective enhancement of the magnetic susceptibility of
one ore more metal oxide values contained in the ore to
the exclusion of the gangue in orddr to permit their
magnetic separation, the improvement comprising:
heating the ore to a temperature of from about 1250
C. to about 5000 C. for a time period of from about
0.25 to about I hour prior to its treatment with the
iron containing compound.
34. The process of claim 33 wherein the ore is selected
from the group consisting of apatite and bauxite.
35. The process of claim 34 wherein the iron containing
compound is ferrocene and the heat pretreatment is
conducted in the presence of a gas selected from the
group consisting of steam and nitrogen.
36. The process of claim 33 wherein the ore is selected
from the group consisting of carnotite, apatite
and bauxite, the iron containing compound is ferrocene
and the heat pretreatment is conducted in the presence
of a gas selected from the group consisting of hydrogen
and carbon monoxide.
37. The process of claim 33 wherein the ore is selected
from the group consisting of shceelite, hematite
and bauxite and the iron containing compound is ferric
acetylacetonate.
38. The process of claim 33 wherein the ore is selected
from the group consisting of carnotite, scheelite,
hematite and bauxite, the iron containing compound is
ferric acetylacetonate and the heat pretreatment is conducted
in the presence of steam.
39. The process of claim 33 wherein the ore is selected
from the group consisting of carnotite, apatite
and hematite, the iron containing compound is ferric
acetylacetonate and the heat pretreatment is conducted
in the presence of hydrogen.
40. The process of claim 33 wherein the ore is selected
from the group consisting of carnotite, scheelite
and apatite, the iron containing compound is ferric
acetylacetonate and the heat pretreatment is conducted
in the presence of carbon monoxide.
41. In a process for the beneficiation of a metal oxide
ore wherein the ore for the specific system is treated
with from about 0.1 to about 100 kilograms of an iron
50 containing compound selected from the group consisting
of ferrous chloride, ferric chloride, ferrocene, ferrocene
derivatives, ferric acetylacetonate and ferric acetylacetonate
derivatives per metric ton of ore at a temperature
within a range of 1250 C. less than the general
decomposition temperature of the metal containing
compound in a specific system for the ore being treated
for a period of time from about 0.05 to about 4 hours to
cause the iron containing compound to react substantially
at the surface of the metal oxide particles to the
substantial exclusion of the gangue particles so as to
alter the surface characteristics of the metal values
thereby causing a selective enhancement of the magnetic
susceptibility of one or more metal oxide values
contained in the ore to the exclusion of the gangue in
order to permit a physical separation between the values
and gangue, the improvement comprising:
heat treatment of the ore prior to treating it with the
iron containing compound.
* * * * *
23
cause the metal containing compound to react substantially
at the surface of the metal oxide particles to the
substantial exclusion of the gangue particles so as to
alter the surface characteristics of the metal values
thereby causing a selective enchancement of the mag- 5
netic susceptibility of one ore more metal oxide values
contained in the ore to the exclusion of the gangue in
order to permit a physical separation, the improvement
comprising:
heat treatment of the ore prior to treating it with the
metal containing compound. 10
14. The process of claim 1 or claim 13 wherein the
metal containing compound is an iron containing compound.
15. The process of claim 14 wherein the iron containing
compound is selected from the group consisting of 15
ferrous chloride, ferric chloride, ferrocene, ferrocene
derivatives, ferric acetylacetonate, and ferric acetylacetonate
derivatives.
16. The process of claim 1 or claim 13 wherein the
metal containing compound is a carbonyl. 20
17. The process of claim 16 wherein the carbonyl is
selected from the group consisting of iron, cobalt, and
nickel.
18. The process of claim 17 wherein the carbonyl
comprises an iron carbonyl.
19. The process of claim 13 or claim 15 wherein the 25
ore is pretreated to a temperature ofat least about 800 C.
for a time period of at least about 0.1 hours.
20. The process of claim 19 wherein the ore is pretreated
to a temperature of from about 1250 C. to about
4500 C. for a time period of from about 0.20 to about 4 30
hours.
21. The process ofclaim 19 wherein the heat pretreatment
is conducted in the presence of a gas selected from
the group consisting of steam, nitrogen, hydrogen, carbon
monoxide, carbon dioxide, ammonia, hydrogen 35
sulfide, sulfur dioxide, methane, air, ethane, propane,
butane and other hydrocarbon compounds in the gaseous
state at the pretreatment temperature.
22. The process of claim 21 wherein the gas is employed
in an amount of at least about 12 cubic meters 40
per hour per metric ton of ore being processed.
23. The process of claim 20 wherein the metal containing
compound is an iron carbonyl and the treatment
of the ore with the iron carbonyl is carried out at a
temperature within a range 150 C. less than the general
decomposition temperature of the iron carbonyl in the 45
specific system for the ore being treated.
24. The process of claim 23 wherein the heat pretreatment
is conducted in the presence of a gas selected from
the group consisting of steam, nitrogen and carbon
monoxide.
25. The process of claim 24 wherein the ore is carnotite.
26. The process of claim 24 wherein the ore is apatite.
27. The process of claim 24 wherein the ore is scheelite.
55
28. The process of claim 24 wherein the ore is cuprite.
29. The process of claim 24 wherein the ore is cassiterite.
30. The process of claim 23 wherein the heat pretreatment
is conducted in the presence of a gas selected from
the group consisting of hydrogen, hydrogen sulfide, 60
sulfur dioxide and ammonia.
31. The process of claim 30 wherein the ore is carnotite.
32. The process of claim 30 wherein the ore is cuprite.
33. In a process for the beneficiation of a metal oxide 65
ore selected from the group consisting of carnotite,
apatite, scheelite, cuprite, cassiterite, bauxite, and hematite
wherein the ore in a specific system is treated with
UNITED STATES PATENT AND TRADEMARK OFFICE
CERTIFICATE OF CORRECTION
PATENT NO.
DATED
INVENTOR(S)
4,205,979
June 3, 1980
Kindig, et al.
ISEALI -'
It is certified that error appears in the above-ldentified patent and that said letters Patent
is hereby corrected as shown below:
Column 1, line 62, delete "or" insert --ore--.
Column 2, line 32, delete "vaporizaton" insert
--vaporization--.
Column 3, line 37, delete "surfacr characterisics" insert
--surface characteristics--.
Column 3, line 53, delete " c hrysocollar" insert
--chrysocolla--.
Column 4, line 61, delete "sulfides" insert --oxides--.
Column 24, line 30, delete "shceelite,"'insert --scheelite,--
9igncd and 9calcd this
Nineteenth Day of MIIY /98/
..fttest:
RENE D. TEGTMEYER
Attestill, Officer