Mekhoa ea ho Ntlafatsa Litšepe tsa Bohlokoa tse kang Khauta le Silevera
Ho hlwekiswa ha ditshipi tsa bohlokwa tse kang kgauta (Au) le silefera (Ag) ke tshebetso ya bohlokwa bakeng sa ho eketsa bohlweki ba ditshipi tse tswang majweng a bohlokwa, di-concentrate, kapa thepa e sebedisitsweng hape (mohlala, mabenyane a sebedisitsweng, ditshila tsa elektroniki, le ditshila tsa diindasteri). Ka lebaka la boleng ba tsona bo hodimo ba moruo le tshebediso e pharalletseng mabenyaneng, di-elektroniki, meriana le matsete, maemo a bohlweki ba kgauta le silefera hangata a hlokeha hore a be hodimo haholo, mohlala, 99,9% (3N) kapa esita le 99,99% (4N). Ho fihlella maemo ana, ho sebediswa mekgwa e fapaneng ya ho hlwekisa, e kgethilweng ho latela mofuta wa thepa e tala, dikahare tsa ho se hlweke, sekala sa tlhahiso, ditjeo, le polokeho le dintho tse nahannweng ka tikoloho.
1. Mehato e Akaretsang ea ho Hloekisa: Ho tloha ho Concentrate ho ea ho Tšepe e Hloekileng
Ka kakaretso, ho hlwekisa khauta le silevera ho kenyelletsa mekhahlelo e 'maloa. Ea pele ke ho lokisa thepa: ho sila, ho sila, ho arohana ka 'mele (mohlala, matla a khoheli kapa ho phaphamala), le ho omisa. Thepa e ntan'o sebetsoa ka ho ntša (ho qhibilihisa kapa ho qhibilihisa) ho tlosa tšepe ea bohlokoa lefikeng kapa matrix ea motsoako. Kamora moo, ho hloekisoa ho etsoa ho tlosa litšila leha e le life tse setseng ho fihlela tekanyo e lakatsehang e fihletsoe.
Ho hlwekisa khauta le silevera ho ka etswa ka pyrometallurgy (ho futhumatsa/ho qhibilihisa), hydrometallurgy (e thehilweng tharollong ya dikhemikhale), kapa electrometallurgy (electrolysis). Ha e le hantle, indasteri hangata e kopanya mekgwa e mmalwa bakeng sa bokgoni le dihlahiswa tsa boleng bo hodimo.
2. Ho Hloekisa ka Pyrometallurgy (Ho Qhibilihisa le ho Arohanya)
a) Karohano ea ho qhibilihisa le ho se qhibilihise (Ho qhibilihisa)
Marung a itseng a tšepe kapa metsoako, litšepe tsa bohlokoa li kopantsoe ka ho li qhibilihisa ka phallo. Sepheo ke ho etsa tšepe e metsi kapa matte e jereng khauta/silefera, ha litšila li fetisetsoa ho slag. Mokhahlelo ona o sebetsa e le "khohlano ea pele," empa ka kakaretso ha o hlahise tšepe e hloekileng haholo.
b) Ho arola silifera/khauta ho loto ka cupellation
Mokhoa oa khale o ntseng o sebelisoa haholo ke cupellation, e kenyeletsang ho futhumatsa motsoako oa loto (Pb) ka tšepe ea bohlokoa tlas'a maemo a oxidizing. Loto e oxidize ho PbO2 (litharge) 'me e monngoa ka har'a thepa e nang le masoba (cupel), ha khauta le silevera tse bohlokoa haholo li sala morao. Mokhoa ona o sebetsa hantle bakeng sa lisampole tse itseng 'me o boetse o sebelisoa ho lekoeng, empa tšebeliso ea oona tekanyong ea indasteri ea sejoale-joale e lekanyelitsoe ke mathata a mosi o tsoang le tlhoko ea taolo ea ts'ebetso.
c) Karohano: Ho Arohanya Khauta le Silevera
Haeba khauta le silevera li le teng e le motsoako (mohlala, ka har'a metsoako ea elektronike kapa mabenyane), ho hlokahala mokhoa oa ho arola lintho tsena tse peli. Ka tloaelo, ho arola ho kenyelletsa ho qhala silevera ka asiti e itseng ka mokhoa o ikhethileng, ho siea khauta e sa qhibilihe. Ho tloha moo, silevera e ka boela ea sebelisoa hape, 'me khauta e ka sebelisoa hape ho fihlela bohloeki.
Pyrometallurgy e matla bakeng sa ho sebetsana le bongata bo boholo le thepa e rarahaneng, empa tšebeliso ea matla le taolo ea mosi o tsoang ke lintho tse tšoenyang haholo.
3. Ho Hloekisa ka Hydrometallurgy (Ho Qhibiliha le ho Pula ka Khetho e Ikgethileng)
Hydrometallurgy e sebelisa lik'hemik'hale tharollong ho qhala khauta/silefera ebe e e arola litšila. Melemo ea eona e kenyelletsa khetho e phahameng le ts'ebeliso ea eona ho mefuta e mengata ea lisebelisoa tse tala, ho kenyeletsoa le lisebelisoa tse sebelisitsoeng hape.
a) Ho silafala ha Khauta (Ho silafala ha Khauta)
E 'ngoe ea mekhoa e tsebahalang haholo ea ho ntša khauta ke cyanidation, moo khauta e qhibilihang ka har'a tharollo ea cyanide moo oksijene e leng teng, e leng se etsang motsoako o qhibilihang. Hang ha khauta e le ka har'a tharollo, ho hlaphoheloa ho etsoa ka:
– Ho monya khabone e kentsweng tshebetsong (CIP/CIL): kgauta e tlangwa ke khabone, ebe e lokollwa (elution) mme e a potlaka.
– Pula ea zinki (Merrill–Crowe): khauta e ntšoa ka tharollo ka thuso ea zinki, e loketseng litharollo tse hlakileng tse nang le khauta e itseng.
Kamora ho hlaphoheloa, khauta ka kakaretso e ntse e hloka ho hloekisoa haholoanyane (mohlala, ka ho e qhibilihisa ka har'a li-dore bars, ebe e hloekisoa ka electro-chemical).
Ntlha ea bohlokoa: tšebeliso ea cyanide e laoloa haholo ka lebaka la chefo ea eona, kahoo mehaho ea sejoale-joale e sebelisa litsamaiso tse koetsoeng, ho ntša chefo lithōleng, le tlhokomelo e tiileng ea tikoloho.
b) Ho Qhibiliha ha Silevera: Nitrate le Thiosulfate
Silevera e etsa matswai/di-complex tse qhibilihang habonolo. Ditshebetsong tse ding, silivera e ka qhibilihisoa e le silefera nitrate mecheng e itseng, ebe e kgutliswa ka pula (mohlala, e le AgCl) kapa e fokotswa ho ba tshepe. Mekgwa e meng e kenyelletsa ditsamaiso tse rarahaneng tse kang thiosulfate tlasa maemo a laolwang. Kgetho ya reagent e susumetswa ke mofuta wa thepa le ditshila tse teng.
c) Ho Hloekisa le ho Hloekisa Tharollo ka Khetho e Ikhethileng
Ka mora hore tshepe e qhibilihe, tharollo hangata e na le ditshila (koporo, tshepe, zinki, nikeli). Mekhoa e sebediswang e kenyeletsa:
– Phetoho ea pH ho thibela li-hydroxide tse litšila.
– Ho eketsa metsoako e etsang hore ho be le metsoako e itseng e sa qhibiliheng.
– Phapanyetsano ea li-ion ho tšoara metsoako ea tšepe ka mokhoa o ikhethileng.
– Ho ntšoa ha di-solvent mererong e itseng ea indasteri.
Katleho ea hydrometallurgy e itšetlehile ka taolo ea k'hemistri ea tharollo: pH, bokhoni ba redox, mocheso le mahloriso a reagent.
4. Ho Hloekisa ka Elektrone: Maemo a Phahameng a Bohloeki
Ho fihlela bohloeki bo phahameng haholo, indasteri e sebelisa haholo ho hloekisa ka motlakase. Molao-motheo: litšepe tse sa hloekang li sebelisoa e le li-anode, tse qhibilihang nakong ea electrolysis. Litšepe tse hloekileng li lula holim'a cathode, ha litšila tse itseng li ntse li sala kapa li monngoa ka har'a seretse.
a) Ts'ebetso ea Wohlwill bakeng sa Khauta
Wohlwell ke ts'ebetso ea ho hloekisa khauta ka motlakase e khonang ho hlahisa khauta e hloekileng haholo (ho fihlela ho 99,99%). Dore ea khauta (khauta e se nang letho) e sebelisoa e le anode, 'me khauta e hloekileng e oela holim'a cathode. Litšila tse kang silevera hangata li etsa precipitate e sa qhibiliheng 'me li bokellana e le slime ea anode, e ntan'o sebetsoa ho fumana litšepe tse ling tsa bohlokoa (ho kenyeletsoa le litšepe tsa sehlopha sa silevera le platinum).
Molemo oa ts'ebetso ena ke boleng bo holimo haholo ba sehlahisoa, empa e hloka taolo e ntle ea electrolyte le meralo ea motheo.
b) Tsamaiso ea Moebius bakeng sa Silevera
Bakeng sa silevera, mokhoa o tsebahalang oa ho hloekisa ka motlakase ke mokhoa oa Moebius. Silevera ea anode ea qhibiliha 'me ea fetoha likristale tsa silevera tse hloekileng holim'a cathode. Litšila tse kang khauta ha li qhibilihe 'me li bokelloa e le seretse sa anode, e leng se etsang hore li sebelisoe ka thoko. Mokhoa ona o sebetsa hantle 'me o sebelisoa hangata limela tsa ho hloekisa silevera.
Ho hlwekisa ka motlakase ho ipabola ho hlahiseng "boemo ba bullion" kapa "litšepe tse ntle," empa ho hloka phepelo ea motlakase, taolo ea tharollo, le ho sebetsana le seretse sa anode se nang le litšepe tsa bohlokoa hammoho le litšila tse kotsi.
5. Ho Hloekisa ho tsoa ho Thepa e Sebedisitsweng Botjha (Merafo ya Ditoropo)
Ka ho phahama ha matlakala a elektroniki, tlhoekiso ea khauta le silevera ho tsoa "merafong ea litoropo" e ntse e e-ba ea bohlokoa le ho feta. Liboto tsa potoloho (li-PCB), lihokelo, le likarolo tse itseng li na le khauta/silefera e nyane empa e le ea bohlokoa. Ts'ebetso ena ka kakaretso e kenyelletsa:
1. Kalafo ea pele ea mechine: ho hlopha, ho sila, karohano ea hona joale ea makenete/eddy.
2. Ho ntsha leaching ka tsela e kgethilweng: ho qhala tshepe ya motheo pele (mohlala, koporo), ebe ho ntshuwa kgauta/silefera.
3. Ho ntlafatsa ho eketsehileng: ho ntsha pula ka tsela e kgethilweng kapa ho ntlafatsa ka motlakase.
Mathata a maholo a ho sebelisa hape ke ho rarahana ha thepa (lipolasetiki, li-resin, li-brominated flame retardants) le monyetla oa ho hlahisa litšila tse kotsi. Ka hona, mekhoa ea sejoale-joale ea ho sebelisa hape e totobatsa litsamaiso tse koetsoeng, ho sefa le kalafo e thata ea litšila.
6. Taolo ea Boleng: Teko ea Dikahare le Setifikeiti
Lihlahisoa tsa khauta e hloekileng le silevera hangata li netefatsoa ka mekhoa ea tlhahlobo e kang:
– Teko ea mollo (bakeng sa ho fumana hantle hore na khauta/silefera e kae).
– XRF (X-ray fluorescence) bakeng sa tlhahlobo e potlakileng ea sebopeho.
– ICP-OES/ICP-MS bakeng sa ho nepahala ho hoholo maemong a litšila tse sa bonahaleng.
Ho phaella moo, bullion bakeng sa mmaraka wa matsete hangata e hloka setifikeiti, ditempe tsa fektheri (koena/fektheri), dinomoro tsa serial, le maemo a itseng a bohloeki.
7. Lintlha tsa Polokeho le Tikoloho
Ho hlwekisa tšepe ea bohlokoa ho pepesetsa indasteri lik'hemik'hale tse senyang le tse chefo, hammoho le mesi e ka bang teng. Mekhoa e metle e kenyelletsa:
– Sistimi ea ho kenya moea le sesepa sa khase.
– Kalafo ea metsi a litšila le ho ntša chefo ea reagent.
– Tšebeliso ea PPE le mekhoa ea tšohanyetso.
– Litlhahlobo tsa tikoloho le ho latela melao.
Mekhoa ea sejoale-joale e boetse e khothaletsa li-reagent tse sireletsang tikoloho haholoanyane, tšebeliso e ntle ea matla le ho hlaphoheloa ha lik'hemik'hale ts'ebetsong.
Qetello
Mekhoa ea ho hloekisa khauta le silevera e kenyelletsa motsoako oa pyrometallurgy, hydrometallurgy, le electrometallurgy, 'me ho hloekisa ka motlakase ke senotlolo sa ho fihlela bohloeki bo phahameng ka ho fetisisa. Khetho ea mokhoa e itšetlehile ka mohloli oa thepa - ebang ke oli, motsoako, kapa litšila tse sebelisitsoeng hape - hammoho le lipheo tsa bohloeki le tsa ho boloka litšenyehelo. Mehleng ea kajeno ea indasteri, ho hloekisa ha ho hloke feela litšepe tsa bohlokoa tsa boleng bo holimo empa hape le polokeho, ho latela melao le boikarabello ba tikoloho. Ka tsoelo-pele ea theknoloji, lits'ebetso tsa ho hloekisa li ntse li tsoela pele ho ea litsamaisong tse khethiloeng haholoanyane, tse bolokang matla le tse tšoarellang ntle le ho beha boleng ba khauta le silevera e hlahisoang kotsing.
