| Identification | More | [Name]
Platinum | [CAS]
7440-06-4 | [Synonyms]
PT
Pt NP
atinum
Platin
3% Pt/C
PT000204
PT004600
PT005101
PT000272
PT000261
PT007920
PT000270
PT007921
PT007128
PT005128
PT000249
PT000246
PT007950
PT005115
PT005327
PT005810
PT005150
PT007300
PT005125
PT000234
PT004800
PT005102
PT004850
PT007940
PT007200
PT005145
PT005109
PT000237
PT005113
PT005108
PT005123
PT000232
PT005116
PT005148
PT005106
PT000220
PT000170
PT004500
PT000228
PT007150
PT007115
PT007961
PT007913
PT005149
PT000236
PT000250
PT005117
PT005840
PT000190
PT000229
PT005107
PT007916
PT005144
PT000263
PT005830
PT000206
PT000203
PT005142
PT000200
PT005124
PT005146
PT005127
PT007500
PT000271
PT004700
Pt paste
PT005140
PT005156
PT005129
PT000230
PT005821
PT000242
PT007130
PT005103
PT007910
PT000248
PT005126
PT000251
PT005820
PT005112
PT007125
PT005141
PT005130
PT005835
PT005825
PT005114
PT007220
PT007120
PT007190
PT005805
PT005122
PT000252
PT000202
PT005110
PT000227
PT007050
PT007260
PT007124
PT005808
PT000210
PT000233
PT000260
PT000235
PT005105
PT005118
PT000240
PT007930
PT005119
PT000201
PT007100
PT000180
PT005155
PT000207
PT005121
PT000265
PT000215
PT007250
PT000208
PT007105
PT005120
PT000264
Platinul
PLATINUM
PLATINIUM
c.i.77795
Platinum1
Platinum2
Platinum3
Platinum4
Platinum5
Platinum6
Platinum7
ESCAT 2431
ESCAT 2441
ESCAT 2621
ESCAT 2931
ESCAT 2941
C.I. 77795
ESCAT 2351
ESCAT 2371
ESCAT 2421
Platinum3.0
KLIGER IRON
Nano Platinu
Platinum, 5%
ESCATTM 226
ESCAT TM 2351
ESCAT TM 2371
ESCAT TM 2421
ESCAT TM 2431
ESCAT TM 2441
ESCAT TM 2621
ESCAT TM 2931
ESCAT TM 2941
Platinum slug
Platinum (1%)
20% Pt/Vulcan
Pt dispersion
40% Pt/Vulcan
PlatinuM wire
10% Pt/Vulcan
PLATINUM METAL
Platinum gauze
Platinum flake
PLATINUM BLACK
PLATINUM SPONGE
PLATINUM CARBON
PLATINUM TUBING
Platinum (0.5%)
platinum，foamed
spongy platinuM
conductive paste
Platinumblackmin
Platinum solution
Platinum - powder
PLATINUM CATALYST
PLATINUM STANDARD
PLATINUM ASBESTOS
PLATINUM ON CARBON
PLATINUM, SULFIDED
PLATINUM ULTRATHIN
COLLOIDAL PLATINUM
PLATINIZED ASBESTOS
ASBESTOS PLATINIZED
PlatinumpowderNmesh
Platinum, nanopowder
Platinum foil50x50mm
Platinum foil25x25mm
liquidbrightplatinum
PLATINUM ON CHARCOAL
PLATINUM ON GRAPHITE
Platinum,5%onalumina
Pt/C Platinum/Carbon
10% Pt on Vulcan XC72
Platinum gauze50x50mm
Platinumblack,min.97%
Platinumpowder(99.9%)
40% Pt on Vulcan XC72
20% Pt on Vulcan XC72
PLATING SOLUTION PT-5
PLATINUM ICP STANDARD
Platinum on carbon 5%
PlatinumonCarbon(10%)
Platinum gauze25x25mm
Platinum gauze50x75mm
PlatinumpowderNmicron
PlatinumfoilNmmcagxmm
Platinum black, 98% Pt
Platinum foil (99.95%)
Platinum foil (99.99%)
Platinum wire (99.95%)
Platinum wire (99.99%)
Liquid bright platinum
PLATINUM, 5% ON CARBON
Platinum,0.5%onalumina
PLATING SOLUTION PT-10
PLATINUM BLACK 98+ 5 G
Platinum foil100x100mm
Platinum on carbon 10%
Platinum(5%) water(71%)
Platinum crucible tongs
PLATINUM POWDER 99+ 1 G
Platinumpowder(99.999%)
PLATINUM: 99.9%, SPONGE
PLATINUM: 99.9%, POWDER
Platinum sponge (99.8%)
Platinum powder, 99.95%
Platinumonaluminapowder
PlatinumspongeNmeshgran
PlatinumwireNmmdiacagcm
Platinum, powder, 99.99%
PLATINUM 99.999%, POWDER
PLATINUM, SPONGE, 99.9+%
Platinum On Carbon(Pt/C)
Platinum sponge (99.95%)
Platinum, on carbon, dry
Platinum, 99.99%, powder
PLATINUM BLACK: 98.8% PT
Catalyst S-201, platinum
Platinum black 20-40m2/g
Platinum(20%) water(58%)
PlatinuM wire,0.5MM dia.
PlatinuM wire,1.0MM dia.
5% PlatinuM on carbon dry
Platinum black 10-20 m2/g
PLATINUM FOIL: 99.99%, 4N
PLATINUM ICP/DCP STANDARD
PLATINUM, POWDER, 99.995%
PLATINUM-ACTIVATED CARBON
PLATINUM, ON CARBON BLACK
Platinum metal wire 99.9%
PLATINUM (PLATINUM BLACK)
Platinumonaluminaxpellets
PlatinumfoilNmmthickcagxmm
PLATINUM WIRE: 99.95%, 3N5
PLATINUM FOIL: 99.95%, 3N5
PLATINUM RHODIUM PALLADIUM
PLATINUM STANDARD SOLUTION
ROYER(R) PLATINUM CATALYST
PLATINUM WIRE: 99.99%, 4N+
PLATINUM POWDER: 99.9%, 3N
5% PlatinuM (S) / charcoal
Platinum Wire/Φ1.0mm/99.95%
PLATINUM, 5% ON CARBON, DRY
Platinum Powder < 60 micron
Platinum/Rhodium 80/20 Foil
PLATINUM/CHARCOAL ACTIVATED
PLATINUM, ON CARBON SUPPORT
PLATINUM SPONGE: 99.8%, 2N8
3% PlatinuM-carbon catalyst
Platinum Wire/Φ1.0mm/99.99%
PLATINUM ON ACTIVATED CARBON
Platinumblacksurfaceareasqmg
PLATINUM SPONGE: 99.95%, 3N5
Platinum, 10% on carbon, dry
PLATINUM POWDER: 99.999%, 5N
Dyesol(R) PT1 platinum paste
Platinum Wire/Φ0.20mm/99.95%
Platinum Wire/Φ0.25mm/99.95%
Platinum Wire/Φ0.50mm/99.99%
Platinum ISO 9001：2015 REACH
Platinum Wire/Φ0.10mm/99.99%
Platinum Wire/Φ0.01mm/99.99%
Platinum Wire/Φ0.050mm/99.99%
Platinum wire/Φ0.025mm/99.99%
PlatinuM Metal, 0.40 MM, Wire
Platinum Wire 0.5 mm diameter
Platinum Wire 0.7 mm diameter
Platinum Wire 0.8 mm diameter
Platinum Wire 1.0 mm diameter
Platinum Wire 0.1 mm diameter
Platinum Wire 2.0 mm diameter
Platinum Wire 0.3 mm diameter
Platinum,10%onactivatedcarbon
Platinum, foil, 0.025mm thick
PlatinumspongeNbluegraypowder
PLATINUM, ON ALUMINA, REDUCED
PLATINUM ON CALCIUM CARBONATE
PLATINUM WIRE DIAMETER 0.5 MM
PLATINUM LID FOR 15ML CRUCIBLE
PLATINUM LID FOR 50ML CRUCIBLE
Platinum, 5% on alumina powder
Platinum Wire 0.05 mm diameter
Platinum Powder 0.2-1.8 micron
Platinum Wire 0.25 mm diameter
Platinum on graphitized carbon
PLATINUM LID FOR 30ML CRUCIBLE
PLATINUM,COARSE POWDER, 99.99%
PLATINUM LID FOR 25ML CRUCIBLE
PLATINUM, GAUZE, 52 MESH, 99.9%
PLATINUM, AAS STANDARD SOLUTION
Platinum, 0.8-2.2 micron, 99.9%
Platinum Wire 0.125 mm diameter
Platinum Wire 0.025 mm diameter
Platinum, soluble salts (as Pt)
Platinumonactivatedcarbonpowder
PlatinumoncarbonAngstromspowder
PLATINUM: 99.9%, WIRE, 1MM DIA.
Platinum,3% on activated carbon
PlatinuM Metal, 22 Mesh, Powder
Platinum, sulfided, on carbon
PLATINUM, GAUZE, 100 MESH, 99.9%
Platinum, 5% on activated carbon
PLATINUM CRUCIBLE, 30ML CAPACITY
platinum coating quality balzers
Platinum (soluable Salt) (in Pt)
Platinum paste, screen printable
PLATINUM CRUCIBLE, 25ML CAPACITY
PLATINUM CRUCIBLE, 50ML CAPACITY
PLATINUM CRUCIBLE, 15ML CAPACITY
PLATINUM SINGLE ELEMENT STANDARD
PLATINUM CRUCIBLE, 10ML CAPACITY
PLATINUM LID TO FIT 10ML CRUCIBLE
PLATINUM METALLO-ORGANIC STANDARD
PLATINUM PLASMA EMISSION STANDARD
Platinum, 0.5% on granular carbon
Platinum, 0.27-0.47 micron, 99.9%
Platinum, nanoparticle dispersion
Platinum black, high surface area
PLATINUM: 99.9%, WIRE, 0.5MM DIA.
Platinum, 0.8-2.2 micron , powder
PlatinuM slug,2MM dia×6MM length.
Platinum Foil/0.05x50x50mm/99.95%
Platinum Foil/0.10x25x25mm/99.95%
Platinum Foil/0.10x50x50mm/99.95% | [EINECS(EC#)]
231-116-1 | [Molecular Formula]
Pt | [MDL Number]
MFCD00011179 | [Molecular Weight]
195.08 | [MOL File]
7440-06-4.mol |
| Chemical Properties | Back Directory | [Appearance]
Platinum is a soft, ductile, malleable, silverwhite metal. It is found in the metallic form and as the arsenide, sperrylite. It forms complex soluble salts, such as Na2PtCl6. It also forms halides. Metallic platinum is insoluble in water. Platinum(IV) chloride is red-brown crystals or powder. | [Melting point ]
1772 °C (lit.) | [Boiling point ]
3827 °C (lit.) | [density ]
21.45 g/cm 3 (lit.) | [refractive index ]
n20/D 1.347
| [Fp ]
3825°C | [storage temp. ]
Flammables area | [solubility ]
Soluble in hot aqua regia. | [form ]
wire
| [color ]
White | [Specific Gravity]
21.45 | [Stability:]
Stable. Platinum black is highly flammable. | [Resistivity]
10.6 μΩ-cm, 20°C | [Water Solubility ]
Insoluble | [Merck ]
14,7529 | [Dielectric constant]
6.5（Ambient） | [Exposure limits]
ACGIH: TWA 1 mg/m3
OSHA: TWA 0.002 mg/m3
NIOSH: TWA 1 mg/m3 | [InChIKey]
BASFCYQUMIYNBI-UHFFFAOYSA-N | [History]
Discovered in South America by Ulloa in 1735 and
by Wood in 1741. Platinum was used by pre-Columbian
Indians. Platinum occurs native, accompanied by small quantities
of iridium, osmium, palladium, ruthenium, and rhodium,
all belonging to the same group of metals. These are
found in the alluvial deposits of the Ural mountains and in
Columbia. Sperrylite (PtAs2), occurring with the nickel-bearing
deposits of Sudbury, Ontario, is a source of a considerable
amount of metal. The large production of nickel offsets
there being only one part of the platinum metals in two million
parts of ore. The largest supplier of the platinum group of
metals is now South Africa, followed by Russia and Canada.
Platinum is a beautiful silvery-white metal, when pure, and
is malleable and ductile. It has a coefficient of expansion almost
equal to that of soda–lime–silica glass, and is therefore
used to make sealed electrodes in glass systems. The metal
does not oxidize in air at any temperature, but is corroded by
halogens, cyanides, sulfur, and caustic alkalis. It is insoluble
in hydrochloric and nitric acid, but dissolves when they are
mixed as aqua regia, forming chloroplatinic acid (H2PtCl6), an
important compound. Natural platinum contains six isotopes,
one of which, 190Pt, is radioactive with a long half-life. Thirtyseven
other radioactive isotopes and isomers are recognized.
The metal is used extensively in jewelry, wire, and vessels for
laboratory use, and in many valuable instruments including
thermocouple elements. It is also used for electrical contacts,
corrosion-resistant apparatus, and in dentistry. Platinum–cobalt
alloys have magnetic properties. One such alloy made of
76.7% Pt and 23.3% Co, by weight, is an extremely powerful
magnet that offers a B-H (max) almost twice that of Alnico
V. Platinum resistance wires are used for constructing hightemperature
electric furnaces. The metal is used for coating
missile nose cones, jet engine fuel nozzles, etc., which must
perform reliably for long periods of time at high temperatures.
The metal, like palladium, absorbs large volumes of hydrogen,
retaining it at ordinary temperatures but giving it up at
red heat. In the finely divided state platinum is an excellent
catalyst, having long been used in the contact process for producing
sulfuric acid. It is also used as a catalyst in cracking
petroleum products. There is also much current interest in
the use of platinum as a catalyst in fuel cells and in its use
as antipollution devices for automobiles. Platinum anodes are
extensively used in cathodic protection systems for large ships
and ocean-going vessels, pipelines, steel piers, etc. Pure platinum
wire will glow red hot when placed in the vapor of methyl
alcohol. It acts here as a catalyst, converting the alcohol to
formaldehyde. This phenomenon has been used commercially
to produce cigarette lighters and hand warmers. Hydrogen
and oxygen explode in the presence of platinum. The price
of platinum has varied widely; more than a century ago it was
used to adulterate gold. It was nearly eight times as valuable as
gold in 1920. The price in January 2002 was about $430/troy
oz. ($15/g), higher than the price of gold. | [Uses]
Platinum is a white noble metal that looks very much like
metallic silver found in copper ore. The name platinum
comes from the Spanish word plata, meaning silver. Platinum
compounds were used in the platinum printing process and
for toning silver images. | [CAS DataBase Reference]
7440-06-4(CAS DataBase Reference) | [NIST Chemistry Reference]
Platinum(7440-06-4) | [EPA Substance Registry System]
7440-06-4(EPA Substance) |
| Questions And Answer | Back Directory | [Uses]
Jewelry; oxygen sensor in internal combustion engines; chemical and electrical industries; dentistry; windings of hightemperature furnaces; electroplating; photography; cancer chemotherapeutic agents | [Chemical Properties]
Platinum is a silvery to whitish-gray metal, that is malleable and ductile (Weast, 1988; Krebs, 2006). It is estimated that the average platinum concentration in the earth’s lithosphere ranges from 0.001 to 0.005 mg/kg (WHO, 1991). It has a vapor pressure of approximately 0mmHg (NIOSH, 2005). Platinum, depending on mining location, is found in sperrylite, cooperite, braggite, and copper–nickel sulfide ores, and in alloys with other members of the platinum group elements (PGE; iridium, osmium, palladium, ruthenium, and rhodium) (Dubiella-Jackowska et al., 2009; Weast, 1988; WHO, 1991). Both elemental platinum and platinum salts are used in industry. Elemental platinum is insoluble in water whereas many of the platinum salts are water soluble to varying degrees, depending on their specific chemical properties (WHO, 1991). Platinum metal is inert and resists corrosion (Krebs, 2006). However, platinum halide salts are considered potent allergens that have a high risk of causing sensitization (Linnett, 2005). Platinum bonds with halogens in its +2 and +4 oxidation state (Krebs, 2006). The charge of the salt and the presence and number of halides, especially chloride, in a complex platinum salt may affect the degree of mammalian sensitivity to a specific salt (Cleare et al., 1976; Mapp et al., 1999; Merget et al., 2000; Ravindra et al., 2004; Pepys, 1980).
| [Uses]
Platinum is found in the environment naturally and from anthropogenic sources. Platinum is primarily used in industry as a catalyst, predominately for the production of vehicle catalytic converters. Platinum is also used in the chemical, electrical, glass, dental, healthcare, pharmaceutical, petroleum, and jewelry fields. In addition to its catalytic properties, platinum, in combination with cobalt, has powerful magnetic properties.
Platinum metal and its alloys have numerous applications. As a precious metal it is used extensively in jewelry. Other important applications include construction of laboratory crucibles and high temperature electric furnaces; in instruments as thermocouple elements; as wire; for electrical contacts; as electrodes; in dentistry; in cigarette lighters; and for coating missile and jet engine parts.
Platinum also is used extensively as a catalyst in hydrogenation, dehydrogenation, oxidation, isomerization, carbonylation, and hydrocracking. Also, it is used in organic synthesis and petroleum refining. Like palladium, platinum also exhibits remarkable ability to absorb hydrogen. An important application of platinum is in the catalytic oxidation of ammonia in Ostwald's process in the manufacture of nitric acid. Platinum is installed in the catalytic converters in automobile engines for pollution control.
|
| Safety Data | Back Directory | [Hazard Codes ]
F,Xi,Xn | [Risk Statements ]
R11:Highly Flammable.
R37:Irritating to the respiratory system.
R20:Harmful by inhalation.
R36/37/38:Irritating to eyes, respiratory system and skin .
R36/37:Irritating to eyes and respiratory system . | [Safety Statements ]
S36:Wear suitable protective clothing .
S7/9:Keep container tightly closed and in a well-ventilated place .
S33:Take precautionary measures against static discharges .
S16:Keep away from sources of ignition-No smoking .
S38:In case of insufficient ventilation, wear suitable respiratory equipment .
S22:Do not breathe dust .
S26:In case of contact with eyes, rinse immediately with plenty of water and seek medical advice .
S14:Keep away from ... (incompatible materials to be indicated by the manufacturer) .
S36/37/39:Wear suitable protective clothing, gloves and eye/face protection .
S27:Take off immediately all contaminated clothing .
S24/25:Avoid contact with skin and eyes . | [RIDADR ]
UN 3264 8/PG 3
| [WGK Germany ]
3
| [RTECS ]
TP2160000
| [TSCA ]
Yes | [HazardClass ]
4.1 | [PackingGroup ]
III | [HS Code ]
28439000 | [Safety Profile]
Questionable
carcinogen with experimental tumorigenic
data by implant route. Finely divided
platinum is a powerful catalyst and can be
dangerous to handle. Used catalysts are
especially dangerous and may be explosive.
May undergo hazardous reactions with
aluminum, acetone, arsenic, carbon +
methanol, nitrosyl chloride, dioxygen
difluoride, ethanol, hydrazine, hydrogen +
air, hydrogen peroxide, lithium, methyl
hydroperoxide, ozonides,
peroxpmonosulfuric acid, phosphorus,
selenium, tellurium, vanadium dichloride +
water. See also PLATINUM
COMPOUNDS. | [Hazardous Substances Data]
7440-06-4(Hazardous Substances Data) | [IDLA]
4 mg Pt/m3 |
| Hazard Information | Back Directory | [General Description]
Silvery, whitish-gray, malleable, ductile metal. Mp: 1772°C; bp: 2187°C. Density: 21.45 g cm-3 at room conditions (very dense). Also shipped as a finely divided powder (PLATINUM(7440-06-4) black), as a sponge, and as particles deposited on a supporting material such as alumina. Has strong catalytic activity in these forms; finely divided PLATINUM(7440-06-4) can be dangerous to handle in the vicinity of other chemicals on this account. Used PLATINUM(7440-06-4) catalysts are particularly dangerous and can be explosive. | [Reactivity Profile]
Massive platinum (lump, ingot, etc.) is generally inert. Dissolves readily in aqua regia (mixture of concentrated hydrochloride and concentrated nitric acids). Reacts rapidly with molten alkali metal oxides and peroxides. Reacts with F2 and Cl2 at red heat. Absorbs large volumes of hydrogen when hot. Catalyzes the exothermic oxidation of ammonia by air. Finely divided platinum is incompatible with aluminum, acetone, arsenic, ethane, hydrazine, hydrogen peroxide, lithium, phosphorus, selenium, tellurium and many fluorides. Explosion can occur upon contact with hydrogen peroxide. Platinum black, sponge and supported catalysts have strong catalytic activity; can be dangerous to handle in the vicinity of other chemicals on this account. Used platinum catalysts are particularly dangerous and can cause explosions. Ethanol or methanol can ignite on contact with a platinum-black catalyst. (Urben 1794). | [Potential Exposure]
Platinum and its alloys have high electrical conductivity and excellent catalytic properties. They are used in relays, contacts and tubes in electronic equipment, in spark plug electrodes for aircraft; and windings in high-temperature electrical furnaces. Platinum alloys are used for standards for weight, length, and temperature measurement. Platinum and platinum catalysts, for example, hexachloroplatinic acid and H2PtCl6, are widely used in the chemical industry in persulfuric, nitric, and sulfuric acid production, in the synthesis of organic compounds and vitamins, and for producing higher octane gasoline. They are coming into use in catalyst systems for control of exhaust pollutants from automobiles. They are used in the equipment for handling molten glass and manufacturing fibrous glass; in laboratory, medical, and dental apparatus; in electroplating; in photography; in jewelry; and in X-ray fluorescent screens. Because platinum complexes are used as antitumor agents, the potential for carcinogenic activity is present; tests to clarify this aspect should be conducted. While low levels of emissions of platinum particulate have been observed from some catalyst-equipped automobiles, the major potential source of Pt is from the disposal of spent catalysts. | [First aid]
If this chemical gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 15 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts the skin, remove contaminated clothing and wash immediately with soap and water. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility. When chloroplatinic acid has been swallowed, get medical attention. If victim is conscious, administer water, or milk. Do not induce vomiting. | [Shipping]
UN3089 Metal powders, flammable, n.o.s., Hazard Class: 4.1; Labels: 4.1-Flammable solid. | [Incompatibilities]
Dust or powder may form explosive mixture with air. Platinum metal is incompatible with aluminum; acetone, arsenic, ethane, hydrazine, hydrogen peroxide; lithium, phosphorus, selenium, tellurium, various fluorides. | [Waste Disposal]
Catalyst disposal is expected to be the largest contributor of Pt to the environment. The value of the metal would help to offset the cost of reclaiming the Pt from discarded catalysts. If direct vehicular emissions of Pt are found to be significant, particulate taps, which are available at reasonable cost, may provide a technological solution. In any event, recovery and recycling is the preferred technique for both health and economic reasons. Details of platinum recovery and recycling from plating wastes, platinum metal refinery effluents; spent catalysts and precious metals scrap have been published. | [Physical properties]
Platinum is classed by tradition and commercial usefulness as a precious metal that is soft,dense, dull, and silvery-white in color, and it is both malleable and ductile and can be formedinto many shapes. Platinum is considered part of the “precious” metals group that includesgold, silver, iridium, and palladium. It is noncorrosive at room temperature and is not solublein any acid except aqua regia. It does not oxidize in air, which is the reason that it is foundin its elemental metallic form in nature. Its melting point is 1,772°C, its boiling point is3,827°C, and its density is 195.09g/cm3. | [Isotopes]
There are a total of 43 isotopes for platinum. Five of these are stable, andanother has such a long half-life that it is considered practically stable (Pt-190 with ahalf-life of 6.5×10+11 years). Pt-190 contributes just 0.014% to the proportion of platinumfound on Earth. The stable isotopes and their contributions to platinum’s existenceon Earth are as follows: Pt-192 = 0.782%, Pt-194 = 32.967%, Pt-195 = 33.832%, Pt-196 = 25.242%, and Pt-198 = 7.163%. All the other isotopes are radioactive and areproduced artificially. They have half-lives ranging from a few microseconds to minutes tohours, and one has a half-life of 50 years (Pt-193). | [Origin of Name]
The name “platinum” is derived from the Spanish word platina, which
means “silver.” | [Occurrence]
Platinum is the 75th most abundant element and, unlike many elements, is found in itspure elemental form in nature, as are deposits of silver and gold. Platinum is widely distributedover the Earth and is mined mainly in the Ural Mountains in Russia and in South Africa,Alaska, the western United States, Columbia in South America, and Ontario in Canada.When found in the mineral sperrylite (PtAs2), it is dissolved with aqua regia to form a precipitatecalled “sponge” that is then converted into platinum metal. It is also recovered as aby-product of nickel mining, mainly in Ontario, Canada. | [Characteristics]
Platinum is the main metal in the platinum group, which consists of metals in both period5 and period 6. They are ruthenium (Ru), rhodium (Ro), and palladium (Pd) in period 5 andosmium (Os), iridium (Ir), and platinum (Pt) in period 6. All six of these metals share someof the same physical and chemical properties. Also, the other metals in the group are usuallyfound in platinum ore deposits.
Platinum can absorb great quantities of hydrogen gas, which makes it useful as a catalystin industry to speed up chemical reactions. | [Definition]
A silvery-white
malleable ductile transition metal. It occurs
naturally in Australia and Canada, either
free or in association with other platinum
metals. It is resistant to oxidation and is not attacked by acids (except aqua regia)
or alkalis. Platinum is used as a catalyst for
ammonia oxidation (to make nitric acid)
and in catalytic converters. It is also used in
jewelry.
Symbol: Pt; m.p. 1772°C; b.p. 3830 ±
100°C; r.d. 21.45 (20°C); p.n. 78; r.a.m.
195.08. | [Definition]
platinum: Symbol Pt. A silverywhite metallic transition element(see also platinum metals); a.n. 78;r.a.m. 195.09; r.d. 21.45; m.p. 1772°C;b.p. 3827±100°C. It occurs in somenickel and copper ores and is alsofound native in some deposits. Themain source is the anode sludge obtainedin copper–nickel refining. Theelement is used in jewellery, laboratoryapparatus (e.g. thermocouples,electrodes, etc.), electrical contacts,and in certain alloys (e.g. with iridium or rhodium). It is also a hydrogenationcatalyst. The elementdoes not oxidize nor dissolve inhydrochloric acid. Most of its compoundsare platinum(II) orplatinum(IV) complexes. | [Production Methods]
Platinum is obtained mainly from copper and nickel ores, and
platinum alloys and by recovery from the catalyst and other
waste. The main stages of platinum production include
extraction of the precious metal concentrate from the ore followed by separation through a complex refining process,
during which the concentrate is dissolved in aqua regia, and
the platinum is precipitated in the form of ammonium(IV)
hexachloroplatinate. The precipitate is then calcinated at
600–700 °C to give platinum sponge, which is then hardened
by melting at high temperatures, such as in the electric arc.
The resultant gray platinum sponge contains 99.95–99.9%
pure metal. Another method of platinum production involves
its reduction to metal from the aqueous platinum salts by
zinc, magnesium, iron, or aluminum. Similar procedures are
used to recover platinum from the catalytic converters and
other waste. The hexachloroplatinic(IV) acid produced by
treating platinum with aqua regia is an important chemical
platinum compound used to obtain various platinum
salts. | [Hazard]
Fine platinum powder may explode if near an open flame. Because platinum is rather inertin its elemental metallic form, it is not poisonous to humans, but some of its compounds,particularly its soluble salts, are toxic if inhaled or ingested. | [Health Hazard]
Exposure to the complex salts of
platinum, especially ammonium hexachloroplatinate and ammonium tetrachloroplatinate,
but not elemental platinum, may cause skin
sensitization and a progressive allergic reaction
that may lead to pronounced asthmatic
symptoms.
The signs and symptoms of hypersensitivity include urticaria, contact dermatitis of the
skin, and respiratory disorders ranging from
sneezing, shortness of breath, and cyanosis to
severe asthma. The latency period from the
first contact with platinum to the occurrence of
the first symptoms varies from a few weeks to
several years. | [Flammability and Explosibility]
Nonflammable | [Environmental Fate]
Inhalation of industrial platinum compounds may be
a problem. The general population is exposed to platinum by
the dermal route, especially from jewelry. The oral route is not
significant because the absorption is very poor.
Platinum can enter the environment through automobile
emissions from the platinum-containing catalytic converter.Relatively high levels of platinum can be found along congested
roadways. A number of chemotherapeutic agents
contain platinum and thus their disposal can lead to environmental
contamination. In industrialized regions, relatively
high concentrations can be found in waterway sediments.
Organic matter binds to the metal. In soil, mobility depends on
pH, redox potential, and chloride concentration. Platinum will
likely only mobilize under highly acidic conditions or in soil
water with high chloride content. Some platinum (IV)
complexes, in the presence of platinum (II), may undergo
methylation by microorganisms. | [Toxicity evaluation]
While the metal itself is systemically of little concern, its salts
are very toxic. The cis-platinum compounds can react with
disulfides and amino groups and form adducts with some bases in nucleic acids. Platinum compounds inhibit a few
enzymes, including leucine aminopeptidase, and the hydrogenases
of malate, alcohol, and lactate. Cisplatin can form
crosslinks between strands of DNA. |
| Questions and Answers (Q&A) | Back Directory | [Description]
Platinum was discovered in Colombia, South America by Ulloa in 1735 and six years later in 1741 by Wood. The metal was isolated from native platinum by Delisle in 1775 and produced in malleable form by Chabaneau in 1786. Wollaston in 1803 developed a method of obtaining pure malleable platinum from crude platinum by extraction with aqua regia. The process led to the discovery of two other platinum group metals, palladium and rhodium, that were found in the aqua regia extract after platinum precipitated. Platinum derived its name from platina originating from the Spanish word plata for silver, because it was thought to be a trivial unwanted material associated with gold in gold mines of Central America.
Platinum occurs in nature as a bright-white cubic crystalline solid with metallic luster associated with other noble metals of its group. Platinum also occurs as the mineral sperrylite, PtAs2, found as tin-white brittle cubic crystals containing 52−57% platinum in certain nickel-bearing deposits. Some other minerals of platinum are cooperite PtS (Pt 80-86%); and braggite(Pt, Pd, Ni)S (Pt 58-60%). The abundance of platinum in the earth’s crust is estimated to be 0.005 mg/kg.
| [Uses]
Platinum metal and its alloys have numerous applications. As a precious metal it is used extensively in jewelry. Other important applications include construction of laboratory crucibles and high temperature electric furnaces; in instruments as thermocouple elements; as wire; for electrical contacts; as electrodes; in dentistry; in cigarette lighters; and for coating missile and jet engine parts.
Platinum also is used extensively as a catalyst in hydrogenation, dehydrogenation, oxidation, isomerization, carbonylation, and hydrocracking. Also, it is used in organic synthesis and petroleum refining. Like palladium, platinum also exhibits remarkable ability to absorb hydrogen. An important application of platinum is in the catalytic oxidation of ammonia in Ostwald's process in the manufacture of nitric acid. Platinum is installed in the catalytic converters in automobile engines for pollution control.
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