| Synonyms |
ANTIMONY-BLACK; ANTIMONY,-REGULUS; ANTYMON-
(POLISH); CI-77050; REGULUS-OF-ANTIMONY; STIBIUM |
| Analytical Methods |
200.7 - 200.8 - 6010 - 6020 - 204.2 |
| Molecular Formula |
Sb |
| Synopsis |
Antimony - (Gr. anti plus monos - a metal not found
alone), Sb; at. wt. 121.760(l); at. no. 51; m.p. 630.63 deg C; b.p. 1587
deg C; sp.gr. 6.691 (20 deg C); valence 0, -3, +3, or +5. Antimony was
recognized in compounds by the ancients and was known as a metal at the
beginning of the 17th century and possibly much earlier. It is not
abundant, but is found in over 100 mineral species. It is sometimes
found native, but more frequently as the sulfide, stibnite (Sb2S3); it
is also found as antimonides of the heavy metals, and as oxides. It is
extracted from the sulfide by roasting to the oxide, which is reduced by
salt and scrap iron; from its oxides it is also prepared by reduction
with carbon. Two allotropic forms of antimony exist: the normal stable,
metallic form, and the amorphous gray form. The so-called explosive
antimony is an ill-defined material always containing an appreciable
amount of halogen; therefore, it no longer warrants consideration as a
separate allotrope. The yellow form, obtained by oxidation of stibine,
SbH3, is probably impure, and is not a distinct form. Natural antimony
is made of two stable isotopes, 121Sb and 123Sb. Forty four other
radioactive isotopes and isomers are now recognized. Metallic antimony
is an extremely brittle metal of a flaky, crystalline texture. It is
bluish white and has a metallic luster. It is not acted on by air at
room temperature, but burns brilliantly when heated with the formation
of white fumes of Sb2O3. It is a poor conductor of heat and electricity,
and has a hardness of 3 to 3.5. Antimony, available commercially with a
purity of 99.999 + %, is finding use in semiconductor technology for
making infrared detectors, diodes, and Hall-effect devices.
Commercial-grade antimony is widely used in alloys with percentages
ranging from 1 to 20. It greatly increases the hardness and mechanical
strength of lead. Batteries, antifriction alloys, type metal, small arms
and tracer bullets, cable sheathing, and minor products use about half
the metal produced. Compounds taking up the other half are oxides,
sulfides, sodium antimonate, and antimony trichloride. These are used in
manufacturing flame-proofing compounds, paints, ceramic enamels, glass,
and pottery. Tartar emetic (hydrated potassium antimonyl tartate) has
been used in medicine. Antimony and many of its compounds are toxic.
Antimony costs about $80/kg (99.5%), and about 75 ct./g (99.999%). |
| Use |
MANUFACTURE OF WHITE METAL, TYPE, BULLETS, BEARING
METAL; IN FIREWORKS, THERMOELECTRIC PILES; COATING METAL, BLACKENING
IRON High purity antimony (>99.999%) has a limited but important
application in the manufacture of semiconductor devices. When alloyed
with elements of Group III-A, the III-V compounds are formed; these have
important applications as infrared devices, diodes, and Hall effect
devices. PRINCIPALLY IN ALLOYS WITH LEAD FOR STORAGE BATTERY GRIDS; IN
ALLOYS WITH OTHER METALS FOR ELECTRICAL & OTHER USES; CHEM INTERMED FOR
OTHER ANTIMONY AGENTS, FIRE RETARDANT CMPD, CERAMIC & GLASS ADDITIVES,
PAINT PIGMENTS, RUBBER VULCANIZATION AGENTS. ALLOYS ARE THE PREDOMINANT
USE OF ANTIMONY METAL BECAUSE ITS BRITTLENESS MAKES DIRECT USE
IMPRACTICAL. |
| Consumption Patterns |
(PRIMARY ANTIMONY): 44% WAS USED IN TRANSPORTATION
APPLICATIONS, MOSTLY STORAGE BATTERY GRIDS; 15% AS A CHEM INTERMED FOR
FIRE-RETARDANT CMPD; 9% AS A CHEM INTERMED FOR RUBBER VULCANIZATION
AGENTS; 6% AS A CHEM INTERMED FOR CERAMIC & GLASS ADDITIVES; 17% AS A
CHEM INTERMED FOR OTHER ANTIMONY CMPD; 5% IN ALLOYS FOR MACHINERY; & 4%
IN MISC USES (1974) FLAME RETARDANTS, 60%; TRANSPORTATION INCLUDING
BATTERIES, 10%; CERAMICS & GLASS, 10%; CHEMICALS, 10%; AND OTHER, 10%
(1985) |
| Apparent Color |
SILVER-WHITE, LUSTROUS, HARD, BRITTLE METAL;
SCALE-LIKE CRYSTALLINE STRUCTURE OR DARK GRAY, LUSTROUS POWDER;
HEXAGONAL; BLUISH TINGE, AND EITHER A COARSELY LAMINATED OR GRANULAR
STRUCTURE; BESIDES THE STABLE METAL THERE ARE 2 ALLOTROPES: YELLOW
CRYSTALLINE AND AMORPHOUS BLACK MODIFICATIONS; Extremely brittle and
slightly pulverizing. |
| Boiling Point |
1635 DEG C |
| Melting Point |
630 DEG C |
| Molecular Weight |
121.75 |
| Density |
6.684 @ 25 DEG C |
| Chemical and Physical Properties
|
NOT AFFECTED BY COLD DIL ACIDS, ATTACKED BY HOT
CONCN SULFURIC ACID, READILY BY AQUA REGIA; SPECIFIC HEAT 0.049 FINELY
DIVIDED REACTS WITH HOT CONCN HYDROCHLORIC ACID. 2 NATURALLY OCCURRING
ISOTOPES: 121 (57.25%); 123 (42.75%); VALENCES: 3, 5. WHEN MELTED FORMS
VOLATILE OXIDE, OXIDIZED BY STEAM OR STRONGLY OXIDIZING SALTS. BURNS
WITH BLUISH-WHITE FLAME WITHOUT VOLATILIZING; AT 900 DEG C IN PRESENCE
OF OXYGEN GIVES OFF FUMES WITH GARLIC SMELL MOHS HARDNESS 3-3.5 Latent
heat of fusion 19,866 J/mol; Electric resistivity= 37 micro-ohm-cm @ 0
deg C; Magnetic susceptibility @ 18 deg C= -99.0X10-6
centimeters-gram-second; Specific heat @ 25 deg C= 25.2 Joules/mole.Kelvin;
Thermal conductivity @ 0 deg C= 25.9 Watt/meter.Kelvin Specific heat
(liquid) @ 2000 deg Kelvin: 0.062 cal/g deg C. The black amorphous
modification exists only at low temperatures. |
| Environmental Impact |
LEAD-ANTIMONY ALLOY IS USED LARGELY IN MANUFACTURE
OF STORAGE BATTERY GRIDS, PEWTER & BRITANNIA METAL, PRINTER'S TYPE, LEAD
SHOT, LEAD ELECTRODES AND BEARING METALS. IN MANY OF THESE PROCESSES THE
GREATEST EXPOSURE IS TO ANTIMONY METAL DUST AND FUME. Antimony process
workers run the highest risk to inhale antimonials. HAZARDOUS EXPOSURES
HAVE BEEN REPORTED IN MINERS OF ANTIMONY ORE IN SOME PARTS OF THE WORLD.
EXPOSURES IN THE PAST (UP TO 1960) IN MINING, CONCENTRATING AND SMELTING
HAVE BEEN COMPLICATED BY THE PRESENCE OF VERY CONSIDERABLE AMOUNTS OF
ARSENIC AND SULFUR DIOXIDE MIXED WITH COPPER, LEAD AND SELENIUM, A
CONDITION NO LONGER EXISTING IN PRESENT DAY REFINERIES. WITH REGARD TO
HEALTH HAZARD EVALUATION OF ANTIMONY EXPOSURES, A CLEAR DISTINCTION
SHOULD BE MADE BETWEEN HAZARDS FROM EXPOSURES IN SMELTING AND REFINING
AND THOSE IN HANDLING AND USE OF THE PRODUCT. IN ANOTHER CLASS OF
EXPOSURES, ANTIMONY ALLOYS, FOUNDRY WORKERS, AND TYPESETTERS MAY BE
EXPOSED TO ANTIMONY FUMES, AND RUBBER COMPOUNDERS MAY SUFFER EXPOSURE TO
ANTIMONY COMPOUNDS. |
| Environmental Fate |
Antimony occurs in the earth's crust as about 2X10-1
to 10X10-1 mg/kg and in seawater at about 2X10-4 mg/kg. It is found
mainly as sulfides and oxides, sometimes as native metal. About 114
minerals containing antimony are known. Other common ores containing
antimony are cervantite, valentinite, livingstonite, jamisonite, and
kermesite. Concentrations of antimony range from 0.5-5 ppm in coal and
30-107 ppm in petroleum. Industrial dust and exhaust gases of cars and
oil fuels are the main sources of antimony in urban air. n soil,
antimony usually ranges from 0.1 to 10 mg/kg dry weight. Sludges used
for manuring soils in Indiana (USA) or collected near Vienna (Austria)
from the Danube River contained antimony concentrations between 4 and 22
mg/kg dried sample. The average range of antimony in dry soils is 2-10
ppm. Acute antimony poisoning can occur from exposure in industrial
operations and from contamination of food containers. Antimony migrates
only in traces from pottery into drinks. The concentrations of antimony
and other elements in human milk obtained from subjects in Italy. More
than 130 samples were obtained from 21 women for about 2 to 3 months
starting 15 days after childbirth. A mean + or - standard deviation of
3.0 + or - 0.4 ng antimony/g of milk (wet basis) was reported for 49
samples of milk obtained from 16 women with antimony levels above the
detection limit of 0.05 ng antimony/g. Antimony values ranged from less
than 0.05 to 12.9 ng/g among the 21 subjects. |
| Drinking WaterImpact
|
In the river Rhine, antimony averages 0.1 ug/l. A
level of 0.2 ug/l has been reported from the northeastern Pacific Ocean.
SEAWATER: CONCENTRATION OF STABLE ANTIMONY IN NORTH ADRIATIC COASTAL
WATERS (YUGOSLAVIA) WAS INVESTIGATED BY NEUTRON ACTIVATION TECHNIQUE.
THE FOLLOWING CONCENTRATIONS WERE OBTAINED: 0.31 UG ANTIMONY/CU DM FOR
FILTERED SEA WATER, AND 45 UG ANTIMONY/CU DM FOR NON-FILTERED SEA WATER.
|
| Disposal |
At the time of review, criteria for land treatment
or burial (sanitary landfill) disposal practices are subject to
significant revision. Prior to implementing land disposal of waste
residue (including waste sludge), consult with environmental regulatory
agencies for guidance on acceptable disposal practices. Treatment and
disposal methods: Chemical treatment, precipitation, recycling. Dissolve
in a minimum amount of concentrated hydrochloric acid (HCl) . Add to
water until the appearance of white precipitate. Add 6M hydrochloric
acid just to dissolve again. Saturate with hydrogen sulfide. After
filtration, wash the precipitate, dry, package, and return to suppliers.
The following wastewater treatment technologies have been investigated
for antimony: Chemical precipitation. |
| Atmosphere |
In Chicago concentrations of antimony in air ranging
from 1.4 to 55 ng/cu m and an average of 32 ng/cu m, respectively /have
been reported/. Somewhat lower levels (0.4 to 4 ng/cu m) were reported
from 7 different sites in the United Kingdom. Urban air contains
0.05-0.06 ppm antimony. FOLLOWING THE INSTALLATION OF AIR POLLUTION
CONTROL DEVICES ON ANTIMONY SMELTERS, ONLY A TRACE AMOUNT OF ANTIMONY
PASSES THROUGH THE FILTER-SCRUBBER. |
