United States Patent [19]
Kindig et al.
[II]
[45]
4,239,529
Dec. 16, 1980
52 Oaims, No Drawings
One or more mineral values of sulfide ores are benefici~
ted by treating the sulfide ore 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 in order to permit a phys~
cal seaparation between the values and gangue.
FOREIGN PATENT DOCUMENTS
179095 7/1954 Austria 75/112
Primary Examiner-L. Dewayne Rutledge
Assistant Examiner-Michael L. Lewis
Attorney, Agent, or Firm-Sheridan, Ross, Fields &
McIntosh
[54] PROCESS FOR BENEFICIATING SULFIDE
ORES
[75] Inventors: James K. Kindig, Arvada; Ronald L.
Turner, Golden, both of Colo.
[73] Assignee: Hazen Research, Inc., Gorden, Colo.
[21] Appl. No.: 86,830
[22] Filed: Oct. 22, 1979
Related U.S. Application Data
[63] Continuation-in-part of Ser. No. 921,584, Jul. 3, 1978,
abandoned, which is a continuation-in-part of Ser. No.
868,416, Jan. 10, 1978, abandoned, which is a continuation-
in-part of Ser. No. 658,258, Feb. 17, 1976, abandoned.
[51] Int. CI.3 C22B 1/00
[52] U.S. Cl. 75/1 R; 75/21;
209/8; 209/9; 209/214; 427/252
[58] Field of Search 75/1 R, 1 T, 21, 28,
75/67, 72, 77, 82, 83, 111, 112; 423/23, 138, 25;
209/8,9, 11,214-214; 427/47, 252-255
[56] References Cited
U.S. PATENT DOCUMENTS
933,717 9/1909 Lockwood 209/8
970,002 9/1910 Wentworth 209/9
2,132,404
2,332,309
2,612,440
2,944,883
3,252,791
3,323,903
3,490,899
3,669,644
3,926,789
3,938,966
4,098,584
[57]
10/1938
10/1943
9/1952
7/1960
5/1966
6/1967
1/1970
6/1972
12/1975
2/1976
7/1978
Dean et al. 423/25
Drummond 427/252
Altmann 75/82
Queneau et al. 75/82
Frysinger et aI 75/82
O'Neil et al. 75/82
Krivisky et al. 423/25
Sato 423/25
Shubert 209/8
Kindig et al. 44/1 R
Kindig et al. 44/1 R
ABSTRACT
PROCESS FOR BENEFICIATING SULFIDE ORES
This invention relates to a means for treating ores to
separate the mineral value(s) from gangue material by
selectively enhancing the magnetic susceptibility of the
mineral value(s) so that they may be magnetically removed
from the gangue.
BACKGROUND ART
4,239,529
1
DISCLOSURE OF THE INVENTION
The process of the present invention entails treating a 45
metal sulfide ore mixture with a metal containing compound
under processing conditions such that the magnetic
susceptibility of the ore is selectively enhanced by
the exclusion of the gangue. The affected ore values
may then be magnetically separated from the less mag- 50
netic constituents.
BEST MODE FOR CARRYING OUT THE
INVENTION
The process of the present invention is particularly
useful for concentrating sulfide minerals. The process
employs the treatment of the sulfide ore with a metal
containing compound in order to selectively enhance
the magnetic susceptibility of various mineral values
contained within the ore. The treated mixture can then
be treated by magnetic means to produce a beneficiated
product.
"Enhancing the magnetic susceptibility" of the ore as
used herein is intended to be defined in accordance with
the following discussion. Every compound of any type
has a specifically defined magnetic susceptibility, which
refers to the overall attraction of the compond to a
magnetic force. An alteration of the surface magnetic
CROSS REFERENCES TO RELATED
APPLICATIONS
This application isa continuation-in-part of application
Ser. No. 921,584 filed July 3, 1978, now abandoned
which is a continuation-in-part of abandoned application
Ser. No. 868,416 filed Jan. 10, 1978 abandoned,
which is a continuation-in-part of now abandoned application
Ser. No. 658,258 filed Feb. 17, 1976.
TECHNICAL FIELD
2
characteristics will alter the magnetic susceptibility.
The metal treatment of the inventive process alters the
surface characteristics of the ore particles in order to
enhance the magnetic susceptibility of the particles. It is
5 to be understood that the magnetic susceptibility of the
original particle is not actually changed, but the particle
itself is changed, at least at its surface, resulting in a
different particle possessing a greater magnetic susceptibility
than the original particle. For convenience of
10 discussion, this alteration is termed herein as "enhancing
the magnetic susceptibility" of the particle or ore
itself.
The sulfide minerals which are capable of undergoing
a selective magnetic enhancement in accordance with
15 the process include the metal sulfides of groups VIE,
VIIB, VIlIB, IE, IIB, IlIA, IVA and VA. These sulfides
preferably specifically include the sulfides of molybdenum,
tungsten, manganese, rhenium, iron, ruthenium,
osmium, cobalt, rhodium, iridium, nickel, palla-
20 dium, platinum, copper, gold, silver, zinc, cadmium,
As is well known, mining operations in the past for mercury, tin, lead, arsenic, antimony and bismuth.
recovering various metals, e.g., lead, copper, have uti- The gangue minerals from which the metal sulfides
lized high grade ore deposits where possible. Many of can be separated include those minerals which do not
these deposits have been exhausted and mining of lower undergo a sufficient magnetic susceptibility enhancegrade
ores is increasing. The processing of these leaner 25 ment as a result of the process. These gangue minerals
ores consumes large amounts of time, labor, reagents, include, for example, silica, alumina, gypsum, muscopower
and water with conventional processing. vite, dolomite, calcite, albite and feldspars, as well as
In addition to the increased expense associated with various other minerals. The term gangue as used herein
the extraction of these metals from low grade ores, refers to inorganic minerals with which sulfide ores are
proposed processes for separation of certain of the sul- 30 normally associated. The term does not include coal.
fide ores are technically very difficult and involve elaborate
and expensive equipment. In many cases the ex- In those ores which contain naturally relatively
pense incurred by such separation would be greater strongly magnetic constituents, such as magnetite, the
than the commercial value of the metal, such that the magnetic material may first be removed by passing the
mineral recovery, while theoretically possible, is eco- 35 mixture through a magnetic separator. The nonmagnomically
unfeasible. netic portion obtained by this precleaning step is then
Accordingly, it is a principal object of this invention subjected to the treatment with a metal containing comto
provide a method of treating ores which separates pound.
the mineral values from gangue material by selectively Prior to the treatment, the ore must be ground to
enhancing the magnetic susceptibility of one or more 40 liberate the metal sulfide particles from the gangue
mineral values in order that they may be magnetically particles, if the respective components do not already
removed from the gangue. exist in this liberated state. The ore may be crushed finer
than necessary to achieve liberation, but this is not generally
economically feasible. It is generally satisfactory
to crush the ore to at least about minus 14 mesh, although
some ores require finer mesh sizes.
Numerous metal containing compounds are capable
of enhancing the magnetic susceptibility of the metal
sulfides 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 alter-
55 ation 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
60 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
65 group are those 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
EXAMPLE 1
Samples of three different synthetic ores, 3% galena,
3% sphalerite and 5% molybdenite, obtained by grind-
6S ing the mineral to minus 65 mesh and mixing with minus
65 mesh sand, were treated at 400° C. with 16 kilograms
of ferrocene per metric ton of ore. The ferrocene had
been dissolved in petroleum ether and mixed with the
4
utilized, the following discussion primarily applies to
vapor injection techniques, specifically iron pentacarbonyl,
as these are generally preferred. Similar considerations,
as can be appreciated, apply to the other de-
5 scribed 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
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
which the iron carbonyl decomposes into iron and carbon
monoxide in indiscriminate fashion, causing a magnetic
enhancement of the gangue as well as the metal
sulfide. The "specific system" is intended to include all
components and parameters, other than, of course, temperature,
of the precise treatment, as the general decom-
20 position temperature varies with different components
and/or different parameters. This decomposition temperature
range can be readily determined by analytical
methods and often a trial and 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 of feed, 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 treatment reaction
is generally conducted for a period of time of 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 about 1 hour.
After the feed mixture containing the metal sulfide
values has been treated with a metal containing compound,
it can then be subjected to a magnetic separation
process to effect the separation of the sulfides. 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 sulfides are liberated at a mesh size of 65
mesh or finer, 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 sulfide surface
characteristics have been altered, the sulfides are often
more amendable to processes such as flotation and
chemical leaching.
4,239,529
3
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, 10
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, naphtha, hexane,
benzene and water; but this, of course, is dependent 15
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 contammg 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 25
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 lOO-mesh, and most preferably
smaller than about 400-mesh. Compounds within this 30
grouping include ferr"ocene and its derivatives, iron salts
of organic acids, and beta-diketone compounds of iron.
Specific examples include ferrous formate, I, I'-diacetyl
ferrocene, and 1,I'-dihydroxymethyl ferrocene.
Various inorganic compounds are also capable of 3S
producing an enhanced magnetic susceptibility. Preferred
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 com- 40
pounds. hon carbonyl is a preferred carbonyl for imparting
this magnetic susceptibility, particularly iron
pentacarbonyl, iron dodecacarbonyl and iron nonacarbony!.
The more preferred metal containing compounds
capable of enhancing the magnetic susceptibil- 4S
ity are iron pentacarbonyl, ferrocene and ferric acetylacetonate,
with iron pentacarbonyl being the most preferred.
The process is applied by contacting the iron containing
compound with the ore at a temperature wherein 50
the iron containing compound selectively decomposes
or otherwise reacts at the surface of the metal sulfide
particles to alter their surface characteristics, while
remaining essentially unreactive, or much less reactive,
at the surface of the gangue particles. The temperature SS
of the reaction is a critical parameter, and dependent
primarily 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 decompo- 60
sition reaction occurs. Suitable results generally occur
over a 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
vapor injection methods may be employed as applicable
depending upon the metal containing compound being
4,239,529
5
ore sample. The petroleum ether was then evaporated
through gentle heating. Thereafter, the treated ore sample
was placed in the reactor and the temperature was
slowly raised to 4000 C. over a two hour period. Identical
samples were treated to the above procedure with
the omission of ferrocene in order to obtain comparative
data. The results are presented below in Table 1.
TABLE 1
6
was not treated with iron carbonyl, was also passed
through the magnetic separator. The products were
chemically analyzedfor copper.
Results of these tests are shown in the following ta5
ble:
TABLE 3
Dosage Weight
Mineral (kg/m ton) Product (%)
Galena 16 Magnetic 5.1
Nonmagnetic 94.9
Calculated Feed 100.0
Galena 0 Magnetic 0.48
Nonmagnetic 99.52
Calculated Feed 100.00
Sphalerite 16 Magnetic 4.1
Nonmagnetic 95.9
Calculated Feed 100.0
Sphalerite 0 Magnetic 0.49
Nonmagnetic 99.51
Calculated Feed 100.00
Molybdenite 16 Magnetic 11.8
Nonmagnetic 82.2
Calculated Feed 100.0
Molybdenite 0 Magnetic 0.68
Nonmagnetic 99.32
Calculated Feed 100.0
Grade
(%) Metal
9.73 Pb
1.79 Pb
2.19 Pb
10.2 Pb
1.99 Pb
2.03 Pb
8.59 Zn
1.34 Zn
1.64 Zn
6.19 Zn
1.63 Zn
1.65 Zn
0.953 Mo
0.064 Mo
0.165 Mo
0.961 Mo
0.143 Mo
0.148 Mo
Metal Sulfide
Distr. (%)
22.6
77.4
100.0
2.4
97.6
100.0
21.5
78.5
100.0
1.8
98.2
100.0
66.6
33.4
100.0
4.4
95.6
100.0
Weight
EXAMPLE 2 Treatment % Copper Copper
Conditions of of Analysis, Distr.
Samples of galena, sphalerite and molybdenite identi- Chalcopyrite Fraction Sample % %
cal with those used in Example 1 were treated with 16 30 Not treated Concentrate 1.27 17.70 25.0
kilograms of ferric acetylacetonate per metric ton of ore with iron (Magnetic)
at a temperature of 2700 C. for 15 minutes. The acetyl- carbonyl
acetonate was injected into the reactor in a volatilized Gangue 98.73 0.68 75.0
(Nonmagnetic)
form. Again, samples of the same ore were subjected to Treated by the Concentrate 4.42 14.30 91.7
the above procedure with the omission of the ferric 35 process as de- (Magnetic)
acetylacetonate in order to obtain comparative blanks. scribed above
The data from these tests are presented below in Table (t25' C., 30 min. Gangue 95.58 0.06 8.3
32 kg. metric (Nonmagnetic)
2. ton Fe(CO)s)
TABLE 2
Dosage Weight Grade Metal Sulfide
Mineral (kg/m ton) Product (%) (%) Metal Distr. (%)
Galena 16 Magnetic 4.5 4.11 Pb 9.4
Nonmagnetic 95.5 1.86 Pb 90.6
Calculated Feed 100.0 1.96 Pb 100.0
Galena 0 Magnetic .52 6.93 Pb 1.9
Nonmagnetic 99.48 1.86 Pb 98.1
Calculated Feed 100.00 1.89 Pb 100.0
Sphalerite 16 Magnetic 5.1 5.63 Zn 16.6
Nonmagnetic 94.9 1.52 Zn 83.4
Calculated Feed 100.0 1.73 Zn 100.0
Sphalerite 0 Magnetic 0.54 10.2 Zn 3.1
Nonmagnetic 99.46 1.72 Zn 96.9
Calculated Feed 100.0 1.77 Zn 100.0
Molybdenite 16 Magnetic 4.3 .801 Mo 20.8
Nonmagnetic 95.7 .137 Mo 79.2
Calculated Feed 100.0 .166 Mo 100.0
Molybdenite 0 Magnetic 0.55 1.04 Mo 4.1
Nonmagnetic 99.45 .136 Mo 95.9
Calculated Feed 100.00 .141 Mo 100.0
EXAMPLE 3 60
A sample of chalcopyrite in a silica-alumina gangue
was treated with 32 kilograms of iron carbonyl per
metric ton of feed, while it was rotating in a glass reaction
vessel at 1250 C. for 30 minutes. After purging with
helium, the treated material was subjected to a magnetic 65
separation step in a Dings cross-belt magnetic separator.
Another sample of chalcopyrite in silica and alumina,
identical in all respects to the first sample except that it
EXAMPLE 4
A small sample of chalcocite mixed with silica was
packed in a glass tube and 57-75 milliliters per minute of
nitrogen gas saturated with iron carbonyl was passed
through the stationary sample bed held at 1950 C. for 30
minutes. A hand magnet was used to separate the material
into two portions, a magnetic and a nonmagnetic
Yield Molybdenum, Molybdenite
Products Wt.(%) (%) Distr. (%)
15 Magnetic 14.9 1.16 88.0
Nonmagnetic 85.1 0.0277 12.0
Calc head 100.0 0.196 100.0
8
TABLE 5
EXAMPLE 7
A sample of molybdenite ground to minus 65-mesh
was mixed with minus 65-mesh silica sand to produce a
5 5% synthetic ore. A sample of this ore was treated at
140' C. for 30 minutes with 8 kilograms of iron pentacarbonyl
per metric ton of feed. Thereafter, the mixture
was subjected to a magnetic separation process to remove
the molybdenum. Pertinent data are given below:
4,239,529
EXAMPLE 5
7
fraction. Microscopic examination clearly showed that
the magnetic fraction was much richer in chalococite
than the nonmagnetic fraction.
A sample of galena in a silica-alumina matrix was
treated in the same manner as described in Example 3
except it was treated with 46 kilograms of iron carbonyl
per metric ton of feed while increasing the temperature
from 25' C. to 125' C. Another sample was treated at 10
115' C. for 30 minutes with 32 kilograms of iron carbonyl
per metric ton of feed. A third sample was not
treated with iron carbonyl. All three samples were then
passed through the cross-belt magnetic separator, with
the results shown in the following table:
TABLE 4
Treatment Lead Lead
Conditions Weight Grade Distr.
of Galena Fraction (%) (%) (%) EXAMPLE 8
No treatment Concentrate 0.06 2.3 0.03 20
Samples of galena, sphalerite and molybdenite were
(Magnetic) ground to minus 65-mesh and mixed with minus 65- Gangue 99.94 4.0 99.97
(Nonmagnetic) mesh silica sand to produce the synthetic ores of 3%
lIS' C. 30 min. Concentrate 0.41 63.3 6.27 galena, 3% sphalerite and 5% molybdenite, respec-
32 kg. Fe(CO)5 (Magnetic)
25 tively. Samples of each of these ores were treated for 30
per metric ton minutes at the temperatures indicated in Table 6 with 8 Gangue 99.59 3.9 93.78
(Nonmagnetic) kilograms of iron pentacarbonyl per metric ton of feed.
25 to 125' C. Concentrate 0.67 47.2 8.06 Comparative results were obtained by treating another
46 kg. Fe(CO)s (Magnetic) sample of each of the ores exactly the same but with the
per metric ton omission of the iron carbonyl. All of the samples were Gangue 99.33 3.6 9\.94 30
(Nonmagnetic) subjected to a magnetic separation process and the results
are given below in Table 6.
TABLE 6
Fe(CO)s
Temp. Dosage Weight Grade Metal Sulfide
Mineral ('C.) (kg/m ton) Product (%) (%) Metal Distr. (%)
Galena 136 8 Magnetic 38.8 6.78 Pb 86.5
Nonmagnetic 61.2 0.673 Pb 13.5
Calculated Feed 100.0 3.04 Pb 100.0
Galena 136 0 Magnetic 0.55 4.07 Ph \.2
Nonmagnetic 99.45 \.90 Pb 98.8
Calculated Feed 100.00 \.91 Pb 100.0
Molybdenite 136 Magnetic 14.0 \.08 Mo 92.1
Nonmagnetic 86.0 O.oI5 Mo 7.9
Calculated Feed 100.0 0.160 Mo 100.0
Molybdenite 136 0 Magnetic 0.57 4.32 Mo 18.9
Nonmagnetic 99.43 0.106 Mo 81.1
Calculated Feed 100.0 0.130 Mo 100.0
Sphalerite 132 Magnetic 8.4 11.5 Zn 56.7
Nonmagnetic 9\.6 0.804 Zn 43.3
Calculated Feed 100.0 \.70 Zn 100.0
Sphalerite 132 0 Magnetic 0.15 3.26 Zn 0.3
Nonmagnetic 99.85 1.54 Zn 99.7
Calculated Feed 100.00 1.54 Zn 100.0
EXAMPLE 6 55
For this example, pure cerussite was mixed with silica
and alumina. After treatment with 32 kilograms per
metric ton iron carbonyl at 105' C. for 30 minutes, only
negligible traces of cerussite mineral were responsive to
the magnet.
EXAMPLE 9
Samples of three different synthetic ores, 5% molybdenite,
3% sphalerite and 3% galena all mixed with
silica sand were treated for 30 minutes with 8 kilograms
of iron carbonyl per metric ton of feed. Each of the
60 samples were treated at the temperature indicated in
Table 7. All of the samples were subjected to a magnetic
separation process, the results of which are presented in
Table 7.
TABLE 7
Fraction of Magnetic Metal
Temp. Mineral-sand Yield, Grade Metal Sulfide
Mineral (%) Mixture Wt.(%) (%) Metal Distr. (%)
Molybdenite 140 Magnetic 8.6 2.10 Mo 90.8
9
4,239,529
10
TABLE 7-continued
Fraction of Magnetic Metal
Temp. Mineral-sand Yield, Grade Metal Sulfide
Mineral (%) Mixture Wt.(%) (%) Metal Distr. (%)
Nonmagnetic 91.4 0.D2 Mo 9.2
Calculated Feed 100.0 0.20 Mo 100.0
Sphalerite 135 Magnetic 14.3 4.20 Zn 67.3
Nonmagnetic 85.7 0.34 Zn 32.7
Calculated Feed 100.0 0.89 Zn 100.0
Galena 135 Magnetic 48.2 1.40 Pb 89.7
Nonmagnetic 51.8 0.15 Pb 10.3
Calculated Feed 100.0 0.75 Pb 100.0
Galena 120 magnetic 7.3 20.9 Pb 81.7
Nonmagnetic 92.7 0.37 Pb 18.3
Calculated Feed 100.0 1.87 Pb 100.0
EXAMPLE 12
A sample of molybdenite was ground to minus 65mesh
and mixed with minus 65-mesh silica sand to produce
a 5% synthetic ore. Several 1 kilogram samples of
this ore were treated with iron carbonyl at a dosage and
temperature indicated in Table 10 for 30 minutes. The
samples were subjected to a magnetic separation process
and the following results were obtained.
TABLE 10
EXAMPLE 10
Samples of 3% galena in Ottawa silica sand sized to
minus 65-mesh, were treated in a reactor with 16 kilograms
of ferrous chloride per metric ton of ore and also 20
with 16 kilograms of ferric chloride per metric ton of
ore. Thereafter the temperature of the reactor was
raised to 3300 C. over 75 minutes. Comparative data
were obtained by treating samples of the ore in the same
manner but with the omission of the ferrous chloride 25
and ferric chloride. Table 8 gives the comparative results.
TABLE 8
Tempera-
Fe(CO)s
Molybdenite
Dosage Weight Grade Metal Sulfide
Mineral (kg/m ton) Product (%) (%) Metal Distr. (%)
Galena none Magnetic 0.50 7.70 Pb 1.7
Nonmagnetic 99.50 2.30 Pb 98.3
Calculated Feed 100.00 2.33 Pb 100.0
Galena 16IFeClz Magnetic 1.13 33.1 Pb 17.3
Nonmagnetic 98.87 1.81 Pb 82.7
Calculated Feed 100.00 2.16 Pb 100.0
Galena 16IFeCI3 Magnetic 2.4 25.7 Pb 72.2
Nonmagnetic 97.6 0.244 Pb 27.8
Calculated Feed 100.0 0.855 Pb 100.0
f
EXAMPLE 11 ture Dosage Weight Grade Distr.
Samples of different sphalerites were ground to minus rc.) (kglm ton) Product (%) (%) (%)
65-mesh and mixed with minus 65-mesh silica sand to a 135 1.5 Magnetic 2.3 6.85 87.0
3% synthetic ores. A sample of each of these ores were Nonmagnetic 97.7 0.024 13.0
treated with 8 kilograms of iron pentacarbonyl per 45 Calculated Feed 100.0 0.181 100.0
135 1.5 Magnetic 2.8 5.80 85.6
metric ton of ore for 30 minutes at the temperature Nonmagnetic 97.2 0.028 14.4
indicated in Table 9. All of the samples were subjected Calculated Feed 100.0 0.190 100.0
to a magnetic separation process and the results are 135 1.5 Magnetic 4.6 3.73 97.3
below in Table 9. Nonmagnetic 95.4 0.005 2.7
50 Calculated Feed 100.0 0.176 100.0
TABLE 9 135 1.5 Magnetic 5.0 3.38 97.3
Nonmagnetic 95.0 0.005 2.7
Sphale- Calculated Feed 100.0 0.174 100.0
rite 135 1.5 Magnetic 5.4 3.05 98.3
Sample Temp. Weight Grade Distr. Nonmagnetic 94.6 0.003 1.7
Origin rC.) Product (%) (%) (%) Calculated Feed 100.0 0.168 100.0
Timmins, 130 Magnetic 3.8 15.0 64.2 55 135 1.5 Magnetic 5.2 3.52 98.0
Onto Nonmagnetic 96.2 0.331 35.8 Nonmagnetic 94.8 0.004 2.0
Calculated Feed 100.0 0.888 100.0 Calculated Feed 100.0 0.187 100.0
Creede, 130 Magnetic 5.5 3.10 36.6 120 11.75 Magnetic 2.6 6.29 84.8
CO Nonmagnetic 94.5 0.312 63.4 Nonmagnetic 97.4 0.030 15.2
Calculated Feed 100.0 0.465 100.0 Calculated Feed 100.0 0.193 100.0
Balmat, 130 Magnetic 4.0 21.9 74.0 60 120 11.75 Magnetic 3.6 4.46 91.2
NY Nonmagnetic 96.0 0.320 26.0 Nonmagnetic 96.4 0.016 8.8
Calculated Feed 100.0 1.18 100.0 Calculated Feed 100.0 0.176 100.0
Beaver 130 Magnetic 9.6 5.02 51.4 120 11.75 Magnetic 4.0 4.23 96.2
County, Nonmagnetic 90.4 0.504 48.6 Nonmagnetic 96.0 0.007 3.8
UT Calculated Feed 100.0 0.938 100.0 Calculated Feed 100.0 0.176 100.0
Beaver 105 Magnetic 6.5 5.12 36.5 65 120 11.75 Magnetic 3.8 4.58 96.8
County, Nonmagnetic 93.5 0.619 63.5 Nonmagnetic 96.2 0.006 3.2
UT Calculated Feed 100.0 0.912 100.0 Calculated Feed 100.0 0.180 100.0
120 11.75 Magnetic 3.6 4.99 96.9
Nonmagnetic 96.4 0.006 3.1
12
to react substantially at the surface of the metal sulfide
particles to the substantial exclusion of the gangue particles
so as to alter the surface characteristics of the metal
sulfide values thereby causing a selective enhancement
of the magnetic susceptibility of one or more metal
sulfide values of the ore to the exclusion of the gangue
in order to permit a physical separation between the
metal sulfide values and the gangue.
2. The process of claim 1 wherein the metal mineral
10 values of the ore undergo an increase in magnetic susceptibility.
3. The process of claim 1 wherein the treated ore is
subjected to a magnetic field to separate the particles
which have been made magnetic from those which have
not.
4. The process of claim 1 wherein the ore is ground to
liberate the metal sulfide particles prior to its treatment
with the metal containing compound.
5. The process of claim 1 wherein the sulfide ore in a
specific system is contacted with the metal containing
4,239,529
EXAMPLE 13
11
TABLE 10-continued
Tem- Molybpera-
Fe(CO)s denite
ture Dosage Weight Grade Distr.
rC.) (kg/m ton) Product (%) (%) (%) 5
Calculated Feed 100.0 0.185 100.0
120 11.75 Magnetic 3.4 5.27 96.9
Nonmagnetic 96.6 0.006 3.1
Calculated Feed 100.0 0.185 100.0
Samples of different minerals were ground to minus
65-mesh and mixed with minus 65-mesh silica sand to
produce 3% synthetic ores. Each sample was treated 15
for 30 minutes with 8 kilograms of iron carbonyl per
metric ton of feed. The temperature of the treatment
varied for the different minerals and is given below as
are the data relating to the wet magnetic recovery of
the metals. 20
TABLE 11
Temp. Yield Metal Metal Sulfide
Mineral rc.) Product Wt.(%) Gr. (%) Metal Distr. (%)
Bornite 140 Magnetic 3.6 29.7 Cu 78.0
Nonmagnetic 96.4 0.313 Cu 22.0
Calculated Feed 100.0 1.37 Cu 100.0
Cinnabar 190 Magnetic 1.6 48.1 Hg 43.9
Nonmagnetic 98.4 1.0 Hg 56.1
Calculated Feed 100.0 1.75 Hg 100.0
Arsenopyrite 125 Magnetic 7.4 1.01 As 31.0
Nonmagnetic 92.6 0.18 As 69.0
Calculated Feed 100.0 0.24 As 100.0
Smaltite 115 Magnetic 1.2 5.37 Co 22.1
Nonmagnetic 98.8 0.23 Co 77.9
Calculated Feed 100.0 0.29 Co 100.0
Smaltite 115 Magnetic 1.2 3.35 Ni 22.5
Nonmagnetic 98.8 0.14 Ni 77.5
Calculated Feed 100.0 0.18 Ni 100.0
Chalcocite 140 Magnetic 3.4 50.8 Cu 90.5
Nonmagnetic 96.6 0.188 Cu 9.5
Calculaled Feed 100.0 1.91 Cu 100.0
Chalcopyrite 140 Magnetic 1.8 20.5 Cu 48.4
Nonmagnetic 98.2 0.401 Cu 51.6
Calculated Feed 100.0 0.76 Cu 100.0
Orpiment 110 Magnetic 20.1 2.0 As 40.5
Nonmagnetic 79.9 0.74 As 59.5
Calculated Feed 100.0 0.99 As 100.0
Realgar 95 Magnetic 23.2 2.02 As 36.5
Nonmagnetic 76.8 1.06 As 63.5
Calculated Feed 100.0 1.28 As 100.0
Pentlandite 105 Magnetic 18.2 0.733 Ni 92.1
in Pyrrhotite Nonmagnetic 81.8 0.079 Ni 7.9
Calculated Feed 100.0 0.145 Ni 100.0
Stibnite 85 Magnetic 7.6 4.82 Sb 48.0
Nonmagnetic 92.4 0.43 Sb 52.0
Calculated Feed 100.0 0.76 Sb 100.0
Stibnite 85 Magnetic 8.1 3.56 Sb 63.4
Nonmagnetic 91.9 0.181 Sb 36.6
Calculated Feed 100.0 0.454 Sb 100.0
Tetrahedrite 117 Magnetic 2.9 4.43 Cu 68.8
Nonmagnetic 97.1 0.06 Cu 31.2
Calculated Feed 100.0 0.19 Cu 100.0
Tetrahedrite 117 Magnetic 2.9 0.256 Zn 31.0
Nonmagnetic 97.1 0.017 Zn 69.0
Calculated Feed 100.0 0.024 Zn 100.0
Tetrahedrite 117 Magnetic 2.9 0.78 Ag 85.3
Nonmagnetic 97.1 0.004 Ag 14.7
Calculated Feed 100.0 0.027 Ag 100.0
Tetrahedrite 117 Magnetic 2.9 2.34 Sb 53.4
Nonmagnetic 97.1 0.061 Sb 46.6
Calculated Feed 100.0 0.127 Sb 100.0
What is claimed is:
1. A process for beneficiating sulfide ores from 65
gangue, excluding coal, which comprises contacting the
sulfide ore with a metal containing compound under
conditions which cause the metal containing compound
compound at a temperature within a range of 1250 C.
less than the general decomposition temperature ofthe
4,;239,529
5
13
metal containing compounci ip a specific syste!J1 for.the
ore being treated. ' .
6. The process of claim 1 wherein the ,metal contain"
ing :::ompound is employed in an amoU'nt from about o.t'
to :lbout 100 kilograms per metric ton of ore.'
7. The process of claim 1 wherein the sylfid~ or~ .is
contacted with the metal containing ,compound for a
time period of from about 0.05 to about 4 hours.
8. A process for the beneficiation of a metal sulfide
ore from gangue, excluding coal, wherein the ore is 10
treated with from about 0.1 to 100 kilograms of Ii metal
containing compound per metric tonpf ore at a temperature
within a range 0(125°, C: less th~!1ihe ,g~neral
dt compoSition temperature of the metal ,?oritliining,
compound in a specific system'for the ore being treat,ed 15
for a period of'time from about 0.05 to about 4 hmirsto
calise the metal containing compound to react substan7
tially at the surface of the metal sulfide particles to the
substantial exclusion of the gangue particles so as to
alter the surface characteristics of the metal sulfide 20
values thereby causing a selective enhancement of the
magnetic susceptibility of one or more metal sulfide
values contained in the ore to the exclusion of the
gangue so as to permit a physical separation between
the metal sulfide values and the gangue. 25
9. The process of claim 1 or claim 8 wherein the metal
containing compound is an iron containing compound.
~o. The process of claim 9 wherein the iron containing
compound is selected from the group consisting of
ferrQus chloride, ferric chloride, ferrocene derivatives, 30
ferric acetylacetonate and ferric acetylacetonate derivatives.
11. The process of claim 1 or claim 8 wherein the
metal containing compound is a carbonyl.
12. The process of claim 11 wherein the carbonyl is 35
selected from the group consisting of iron, cobalt and
nickel.
13. The process ofclaim 12 wherein the iron carbonyl
comprises iron pentacarbonyl.
14. The process of claim 12 wherein the metal con- 40
taining compound is employed in an amount of from
about 1 to about 50 kilograms per metric ton of ore and
the process is carried out at a temperature within a
range of 50° C. less than the general decomposition
temperature of the metal containing compound in a 45
specific system for the ore being treated for a period of
time from about 0.15 to about 2 hours.
15. The process of claim 14 wherein the metal contabing
compound is employed in an amount of from
about 2 to about 20 kilograms per metric ton of ore. 50
16. The process of claim 15 wherein the metal containing
compound is iron carbonyl and the treatment
process is carried out at a temperature within a range of
15° C. less than the general decomposition temperature
of the iron carbonyl in the specific system for the ore 55
being treated.
17. The process of claim 1 or claim 8 wherein the
metal sulfide values are physically separated from the
gangue by a magnetic separation process.
18. The process of claim 17 wherein the magnetic 60
separation process is a wet magnetic separation process.
19. The process of claim 1 or claim 8 wherein the
metal sulfide values are physically separated from the
gangue by an electrostatic technique.
20. The process of claim 10 wherein the iron contain- 65
ing compound is selected from the group consisting of
ferrous chloride, ferric chloride, ferrocene and ferric
acetylacetonate.
14:
2'., The ,PI'o.ces~ofslaim20,:whereinthe iron containing'compoundis"
ferrouschloricie. ".
22. The processor dIaim 20 wherein the iron co~taining
compound is ferric chioride. ' ' , "
23. The process of claim 20 wherein the iron contain~
iIigcbmpound'is fetrocene:' -
24. The process of claim 20 wherein the iron containingcompound.
is ferric acetylacetonate.
25. A process for the beneficiation of a metal sulfide
ore from gangue, excluding coal, selected from the
group consisting of galena, molybdenite, sphalerite,
bqrnite, cinnabal:',. arsenopyrite, -smaltite, chalcocite,
chalcopyrite, oqJiment, realgar, pentiandite in pyrrhotitfi"
s~ibhite. and tetrahedrite ,which' comprises for the
ore in a specific system 'contacting the sulfide ore with
an iron coritaining compound selected from the group
consisting of ferrous chloride, ferric chloride, ferrocene,
ferric acetylacetonateand iron pentacarbonyl at a
temperature within a range of 125° C. less than the
general decomposition temperature of the iron contlj,ining
compound in the specific system for the ore being
treated for a period of time from about 0.15 to about 2
hours to cause the iron containing compound to react
substantially at the surface of the metal sulfide particles
to the substantial exclusion of the gangue particles so as
to alter the surface characteristics of the metal sulfide
values thereby causing a selective enhancement of the
magnetic susceptibility of one or more metal sulfide
values of the ore to the exclusion of the gangue in order
to permit a magnetic separation between the metal sulfide
values and the gangue.
26. The process of claim 25 wherein the iron containing
compound is iron pentacarbonyl employed in an
amount from about 1 to about 50 kilograms per metric
ton of ore and the process is conducted at a temperature
within a range of 15° C.less than the general decomposition
temperature of the iron carbonyl in the specific
system for the ore being treated for a time period of
from about 0.15 to about 2 hours.
27. The process of claim 26 wherein the metal sulfide
ore is galena.
28. The process of claim 26 wherein the metal sulfide
ore is molybdenite.
29. The process of claim 26 wherein the metal sulfide
ore is sphalerite.
30. The process of claim 26 wherein the metal sulfide
ore is bornite.
31. The process of claim 26 wherein the metal sulfide
ore is cinnabar.
32. The process of claim 26 wherein the metal sulfide
ore is arsenopyrite.
33. The process of claim 26 wherein the metal sulfide
ore is smaltite.
34. The process of claim 26 wherein the metal sulfide
ore is chalcocite.
35. The process of claim 26 wherein the metal sulfide
ore is chalcopyrite.
36. The process of claim 26 wherein the metal sulfide
ore is orpiment.
37. The process of claim 26 wherein the metal sulfide
ore is realgar. '
38. The process of claim 26 wherein the metal sulfide
ore is pentlandite.
39. The process of claim 26 wherein the metal sulfide
ore is stibnite.
40. The process of claim 26 wherein the metal sulfide
ore is tetrahedrite.
• • • • •
16
47. The process of claim 45 wherein the metal sulfide
ore is molybdenite.
48. The process of claim 45 wherein the metal sulfide
ore is sphalerite.
49. The process of claim 25 wherein the iron containing
compound is ferrous chloride which is employed in
!In amount from about 2 to about 20 kilograms per metric
ton of ore for a period of time from about 0.15 to 2
hours.
SO. The process of claim 49 wherein the metal sulfide
ore is galena.
51. The process of claim 25 wherein the metal containing
compound is ferric chloride which is employed
in an amount from about 2to about 20 kilograms per
metric ton of are for a time period from about 0.15 to
about 2 hours.
52. The process of claim 51 wherein the metal sulfide
are is galena.
15
41. The process of claim 25 wherein the iron c~mtain"
ing compound is ferrocene which is employed in an
amount from about 2 to about 20 kilograms per metric
ton of ore.
S 42. The process of claim 40 wherein the metal sulfide
ore is galena.
43. The process of claim 40 wherein the metal sulfide
ore is molybdenite.
44. The process of claim 40 wherein the metal sulfide 10
ore is sphalerite.
45. The process of claim 25 wherein the metal containing
compound is ferric acetylacetonate which is
employed in an amount from about 2 to about 20 kilo- IS
grams per metric ton of ore for a time period of from
about 0.25 to I hour.
46. The process of claim 45 wherein the metal sulfide
ore is galena.
20
2S
30
3S
40
4S
SO
S5
60
65