Chirongwa cheZvenzvimbo neZvikushandisa zveNsimbi Iri Dense
Platinum isimbi yakasimba, yakasimbiswa uye isina ruvara inowanzoshandiswa muzvishongo zvekunaka kwayo, sirivha-sechimiro, uyewo mune zvechiremba, zvemagetsi, uye makemikari yekushandiswa nekuda kwezvinhu zvakasiyana-siyana uye zvakasiyana-siyana zvemakemikari uye masimba.
Properties
- Atomic Symbol: Pt
- Atomic Number: 78
- Element Category: Transition metal
- Kuwandisa: 21.45 g / cm 3
- Melting Point: 3214.9 ° F (1768.3 ° C)
- Boiling Point: 6917 ° F (3825 ° C)
- Kuoma kwaMos: 4-4.5
Mamiriro
Platinum yesimbi ine nhamba inobatsira, iyo inotsanangura kushandiswa kwayo mune zvakasiyana-siyana zvemabhizimisi. Icho chimwe chezvinhu zvakanyanyisa zvesimbi - zvinenge kaviri zvakaoma semutungamiri - uye zvakasimba kwazvo, zvichipa simbi yakaisvonaka yakagadzikana kusagadzikana. Mutevedzeri akanaka wegesi, platinum inogonawo kushandiswa uye ductile.
Platinum inofungidzirwa sesimbi inoshandiswa nehupenyu nokuti haisi inotyisa uye yakagadzikana, saka haigoni kuita, kana kuti inokanganisa miviri yomuviri. Ongororo ichangobva kuitika yakaratidzawo platinum kuti irege kukura kwemamwe masero anouraya.
Nhoroondo
Nhengo ye platinum boka resimbi (PGMs) , iyo inosanganisira platinum, yakashandiswa kupfekedza Casket yeThebes, guva reEgipita rakadzoka kusvika munenge 700 BC. Iyi ndiyo yekutanga kududzirwa kweplatinum, kunyange pre-Columbian South America yakaitawo zvishongo kubva kune ndarama uye platinum alloys .
VaSpanish vatongi vaive vekutanga veEurope kusangana nematare, kunyange vakaona kushaya njodzi mukutsvaka kwavo sirivha nekuda kwechimiro chakafanana. Vakataura nezvesimbi sezvakaita Platina - shanduro yePlata , shoko rechiSpanish rinoreva sirivha - kana Platina del Pinto nekuda kwekuwanikwa kwaro mumhenderekedzo pamahombekombe egungwa rePinto muzuva ranhasi Columbia.
Kunyange zvazvo akadzidza nemitauro yakawanda yeChirungu, French uye yeSpanish pakati pezana remakore rechi18, Francois Chabaneau ndiye wokutanga kubudisa mufananidzo wakachena weplatum metal muna 1783. Muna 1801, mutauro weChirungu William Wollaston akawana nzira yekubvisa zvakasimba simbi kubva ore, iyo yakafanana chaizvo neyakashandiswa nhasi.
Platinum yesimbi yakaita sirivha-yakaita seyo yakakurumidza kuiita chinhu chinokosha pakati pevahedheni uye vapfumi vakange vachitsvaga zvishongo zvakaitwa kubva kune zvigadzirwa zvinokosha zvekare.
Kuwedzera kwekutsvaga kwakaunza kuwanikwa kwemahombekombe makuru muUral Mountains muna 1824 uye Canada muna 1888, asi kuwana kuti zvichishandura ramangwana replatinum harina kuuya kusvika muna 1924 apo murimi weSouth Africa akakwidza muputi weplatinum mumvura. Izvi pakupedzisira zvakatungamirira kuongorori we geologist kuwanikwa kwaHans Merensky weBushveld yakaoma kunzwisisa, iyo huru pane platinum pasi.
Kunyange zvazvo mamwe maitiro ekushandiswa kweplatinum (semuenzaniso spark plug-coatings) aive achishandiswa pakati pezana remakore rechi20, dzakawanda zvemazuva ano magetsi, zvekurapa uye zvigadzirwa zvemotokari zvakangogadziriswa kubva muna 1974 apo mitemo yehutano yemhepo muUnited States yakatanga nguva yekuzvipira.
Kubvira panguva iyoyo, platinum yakavewo iyo inoshandiswa uye inotengeswa kuNew York Mercantile Exchange uye London Platinum uye Palladium Market.
Kugadzirwa
Kunyange zvazvo platinum yakawanda kakawanda inowanzoitika munzvimbo dzakachengetwa, platinum uye platinum boka resimbi (PGM) vanogadzira minda kazhinji vanobvisa simbi kubva kune sperrylite uye cooperite, maviri platinum ine ores.
Platinum inowanikwa pamwe chete nemimwe PGMs. MuSouth Africa's Bushveld complex uye nhamba shomanana yemamwe masimbi, maPGM anoitika muhuwandu hwakawanda kuitira kuti zvive zvekugadzirisa chete kubvisa zvidhina izvi; asi, kuRussia's Norilsk neCanada Sudbury inopa platinum nemamwe maPGM inotorwa sezvi-zvinogadzirwa nickel nemhangura .
Kubvisa platinum kubva kune ore zvose zviri zviviri uye basa guru. Inogona kutora kusvika kumwedzi 6 uye matani 7 kusvika ku12 ore kubudisa imwe troy ounce (31.135g) yeplatinum yakachena.
Danho rokutanga mune izvi nderokupwanya platinum rine ore uye kuisita mumagetsi ane mvura; imwe nzira inonzi "froth flotation".
Panguva yekufamba, mhepo inoputirwa mumvura-slurry. Platinum particles makemikari anosungira kune oksijeni uye inomira kune imwe nzvimbo mu froth iyo yakagadzirirwa kuti iwedzere kunatswa.
Kana imwe yakasvava, iyo yakakanyiwa yakave inenge iine pasi pe1% platinum. Icho chinotonhora kunopfuura 2732F ° (1500C °) mumagetsi emagetsi uye mhepo inoputirwazve zvakare, kubvisa tsvina nesimbi nesarufu.
Electrolytic uye makemikari maitiro anoshandiswa kubvisa nickel, mhangura uye cobalt , zvichiita kuti pave nekufunganya kwe 15-20% PGMs.
Aqua regia (inokonzerwa ne nitric acid uye hydrochloric acid) inoshandiswa kuparadza platinum yechipfuva kubva mumigodhi inogadziriswa nekugadzira chlorine inosungira platinum kuumba chloroplatinic acid.
Muchitsauko chekupedzisira, ammonium chloride inoshandiswa kuchinja chloroplatinic acid kusvika kuammonium hexachloroplatinate, iyo inogona kupiswa kuti iumbe pure platinum yakachena.
Mashoko akanaka ndeokuti haasi platinum yose inobudiswa kubva kunzvimbo dzepamusoro mune ino yakareba uye inodhura hurongwa. Maererano nenhamba dzeUnited States Geological Survey (USGS), inenge 30% yemamiriyoni 8,53 emaplatinum akabudiswa munyika yose muna 2012 yakabva kune mamwe mabhuku.
Nehurongwa hwayo huri muzinda weBushveld, South Africa ndiyo inonyanya kubudisa mupiki weplatinum, inopa zvinopfuura 75% zvezvinoda zvenyika, nepo Russia (25 tonnes) neZimbabwe (7.8 tonnes) zvakarewo vhizha guru. Anglo Platinum (Amplats), Norilsk Nickel uye Impala Platinum (Implats) ndivo vakakura zvikuru vanogadzira platinum metal.
Applications
Nokuda kwesimbi yakashambadzirwa gore negore inongova matani 192, platinum inowanikwa mukati, uye inotsanangurira kugadzirwa kwe, zvinhu zvakawanda zvezuva nezuva.
Iyo yakashandiswa zvikuru, inotora makumi mana kubva muzana yezvokudiwa, iyo indasitiri yezvishongo iyo inonyanya kushandiswa mualloy inoita goridhe chena. Inofungidzirwa kuti inopfuura 40% yemhete dzechato dzinotengeswa muUnited States dzine platinum. IU.SA, China, Japan, uye India ndiyo misika huru yezvigadzirwa zveplatinum.
Platinum's corrosion resist and high-temperature stability inoita kuti zvive zvakanaka sechinhu chinokonzera mukugadzirisa makemikari. Zvinokonzera kukurumidza kushandiswa kwemakemikari pasina ivo pachavo kushandiswa kwemakemikari mukuita.
Platinum's main application in this sector, accounting for about 37% of total demand for the metal, is in catalytic converters for automobiles. Vashanduri vechiCataltic vanopedza makemikari anokuvadza kubva pakuneta kwekubudisa mhepo kuburikidza nekuita maitiro anoshandura zvinodarika 90% emahydrocarboni (carbon monoxide uye oxidhi ye nitrojeni) mune zvimwe, zvishoma zvisingakuvadzi, mishonga.
Platinum inoshandiswawo kushandisa nitric acid uye petroli; kuwedzera ma octane mazinga ari mafuta.
Mumakambani emagetsi, platinum crucibles inoshandiswa kuita semiconductor makristal for lasers, asi zvinyorwa zvinoshandiswa kugadzira magnetic disks pamakombiyuta akaoma uye kuchinjana mavhisi mumotokari yekudzivirira.
Kuda kubva kumakambani ezvokurapa kuri kukura sa platinum inogona kushandiswa iyo yose iyo inogadzirisa zvinhu mumagetsi emagetsi emhepo, pamwe chete nemapiritsi emakemikari uye retinal, uye nokuda kwemaitiro ayo anopesana nekenza mune zvinodhaka (eg carboplatin uye cisplatin).
Pasi apa pane mamwe mazita emamwe maitiro akawanda eplatinum:
- Ne rhodium, yakashandiswa kuita yakakwirira-kutema thermocouples
- Kugadzira optically pure, girazi rakaputika reTV, LCD, uye vatariri
- Kugadzira threads yegirazi ye fiber optics
- Muchidimbu chinoshandiswa kuumba mazano emotokari uye aeronautic spark plugs
- Sekutsiva chinzvimbo chegoridhe mune zvemagetsi
- Mukupfekedzwa kwe ceramic capacitors mune zvemagetsi
- Muchidimbu chemazinga ekushisa kwejet fuel nozzles uye missile mapepa emhino
- Muzvinyorwa zvemazino
- Kuita michero yakakwirira
- Mu utsi uye carbon monoxide detectors
- Kugadzira silicones
- Mukupfekedza razors
Sources:
Wood, Ian. 2004. Platinum . Benchmark Books (New York).
I International Platinum Group Metals Association (IPA).
Chinhu: http://ipa-news.com/
USGS: Platinum Group Metals.
Chinhu: http://minerals.usgs.gov/minerals/pubs/commodity/platinum/