Metal Profile: Iridium

Iridium chii?

Iridium yakaoma, ine brittle, uye inoyevedza platinum boka resimbi (PGM) inonyatsogadzikana pamatambo makuru uye mumamiriro emakemikari.

Properties

• Atomic Symbol: Ir
• Atomic Number: 77
• Element Category: Transition Metal
• Kuwandisa: 22.56g / cm ³
• Melting Point: 4471 ° F (2466 ° C)
• Nyaya Yakabikira: 8002 ° F (4428 ° C)
• Mohs kuoma: 6.5

Mamiriro

Pure Iridium metal isimbi yakasimba uye ine dense shanduko yesimbi.

Iridium inofungidzirwa kuti ndiyo inonyanya kusagadzikana simbi yakachena nokuti inopikisa kurwisana nemashizha, miviri, mineral acids uye aqua regia (musanganiswa we hydric uye nitrochloric acids), asi ichingova pangozi yekurwiswa nemarita akanyanya kushandiswa se sodium chloride uye sodium cyanide.

Yechipiri yakawanda kwazvo yezvinhu zvose zvematare (shure kwega chete osmium, kunyange ichi ichi kukakavadzana), iridium, yakafanana nedzimwe PGMs, ine nzvimbo yakanyunguduka yepamusoro uye simba rinogadziriswa pamasikati makuru.

Metallic iridium ine yechipiri yepamusoro yehutano hwezvinhu zvose zvesimbi, zvinoreva kuti yakaoma kwazvo uye isingagadziri kududzirwa, zviito zvinoita kuti zvive zvakaoma kuita muzvinhu zvinoshandiswa asi zvinoita kuti zvive chinhu chinokosha -kusimbisa kuwedzera. Platinum , iyo yakashongedzwa ne 50% iridium, somuenzaniso, inoda kusvika gumi zvakanyanya zvakaoma kupfuura iyo inenge yakachena.

Nhoroondo

Smithson Tennant anorumbidzwa nekuwanikwa kwe iridium paanenge achiongorora platinum ore muna 1804.

Zvisinei, yakawanda yendarira yeinamu yakanga isina kubviswa kwemamwe makore gumi uye chimiro chakanaka chesimbi chakanga chisina kubudiswa kusvikira makore makumi mana pashure pokunge Tennant awanikwa.

Muna 1834, John Isaac Hawkins akatanga shanduro yekutanga yekutengesera ye iridium. Hawkins akanga achitsvaga chinhu chakaoma kuti ape mapepa epeni aisazopedza kana kuputsa mushure mokushandisa zvakare.

Mushure mekunge anzwa pamusoro pezvinhu zvezvinhu zvitsva, akawana imwe iririm-ine chinyorwa kubva kune waishandira pamwe naTennant William Wollaston ndokutanga kubudisa yekutanga iridium-tipped golden pens.

Muchikamu chechipiri chezana remakore rechi19, sangano reBritish Johnson-Matthey vakatungamirira pakugadzira nekudhinda iridium-platinum alloys. Imwe yekutanga kushandiswa kwaive muWitworth nyanga, iyo yakaona chiito panguva yeAmerica Civil War.

Kusati kwasvika iridium alloys, cannon zvimedu zvimedu, izvo zvakagadziridza ganisi remoto, zvakange zvakakurumbira nokuda kwekunyengedza sechikonzero chekudzima kwemawere nekupisa kwakanyanya. Yakanga ichitaura kuti zvidimbu zvakagadzirwa nealdium-containing alloys zvakachengetedza chimiro chavo uye chimiro chemhosva dzinopfuura 3000.

Muna 1908, Sir William Crookes akagadzira yekutanga iridium crucibles (midziyo inoshandiswa pakushandura kwekemikari yemakemikari), iyo yaakagadzira naJohnson Matthey, uye yakawana yakave nezvakanaka zvikuru pamusoro pemidziyo yakachena yeplatinum.

Yokutanga iridium-ruthenium thermocouples yakagadzirwa kumavambo ekuma1930 uye kuma1960 apera, kusimbiswa kwema dimensionally stable anodes (DSAs) zvakanyanya kuwedzera chido chechikamu.

Kubudirira kweeodhi, iyo inosanganisira titanini yakafukidzwa nePGM oksidi, yakanga iri kufambira mberi kukuru mumushonga wekloralkali yekubudisa chlorine uye caustic soda uye anode inoenderera kuva mutengi mukuru we iridium.

Kugadzirwa

Kufanana nePGMs yose, iridium inobviswa se-ne-chigadzirwa nickel , uye kubva kuPGM rich ores.

PGM inogarisa inowanzotengeswa kuti igadziridze iyo inonyanya kugadziriswa kwesimbi imwe neimwe.

Kana imwe nguva iripo sirivha, ndarama, palladium , uye platinum zvabviswa kubva munharaunda, masara akasara anonyungudutswa ne sodium bisulfate kuitira kuti abvise rhodium .

Izvo zvakasara zvinogadziriswa, izvo zvine iridium, pamwe ne ruthenium uye osmium, yakanyungudutswa ne sodium peroxide (Na ₂ O ₂ ) kubvisa ruthenium uye osmium salts, zvichisiya kusachena kwakakwana iridium dioxide (IrO ₂ ).

Nokupedza iridium dioxide mu aqua regia, mutezo weokisijeni unogona kubviswa paunenge uchibudisa mhinduro inonzi ammonium hexachloroiridate. Kusvibiswa kwekudziya mvura, inoteverwa nekupisa nehydrogen gesi, pakupedzisira kunoguma mu puredium iridium.

Kubudiswa kwepasi rose kwe iridium kunongowanikwa kusvika pamatani 3-4 pagore. Zvizhinji zveizvi zvinobva pakugadzirwa kwepurasitiki, kunyange zvazvo iri iridium inoshandiswa zvakare kubva mumashandisi ekugadzirisa uye zvigaro.

South Africa ndiyo inonyanya kukosha ye iridium, asi simbi inobviswawo kubva kune nickel ores muRussia neCanada.

Vaparimi vese vakakura vanosanganisira Anglo Platinum, Lonmin, uye Norilsk Nickel .

Applications

Kunyange zvazvo iridium inowanikwa mumhando dzakasiyana-siyana dzemishonga, kushandiswa kwayo-kushandiswa kunogona kuiswa muzvikamu zvina:

1. Electrical
2. Kemikari
3. Electrochemical
4. Zvimwe

Maererano naJohnson Matthey, kushandiswa kwemagetsi kunoshandisa anenge makumi matatu kubva muzana emafuta ema1980 000 anodyiwa mugore ra2013. Maitiro ekugadzira magetsi aiva makumi mapfumbamwe nezana emuzana eiridium inoshandiswa, asi makambani emakemikari akadya anenge 10 muzana. Zvimwe zvinoshandiswa zvakapoteredza zvakasara 42 kubva muzana zvekuda kwezvose.

_Sources

_{Johnson Matthey. PGM Market Review 2012.}

_{http://www.platinum.matthey.com/publications/pgm-market-reviews/archive/platinum-2012}

_{USGS. Mineral Commodity Summaries: Platinum Group Metals. Chinhu: http://minerals.usgs.gov/minerals/pubs/commodity/platinum/myb1-2010-plati.pdf}

_{Chaston, JC "Sir William Crookes: Tsvakurudzo pamusoro pe Iridium Crucibles uye Kuratidzira kweMikati Platinum". Platinum Metals Review , 1969, 13 (2).}