Inqubo yokushisa okuphezulu kwe-cyanidation yokuthola izinsimbi eziyigugu kuma-catalyst ezimoto

Isingeniso

Izinsimbi zeqembu le-Platinum (ama-PGM), okuhlanganisa i-platinum (Pt), i-palladium (Pd), kanye ne-rhodium (Rh), zibaluleke kakhulu ezimbonini ezahlukene. Embonini yezimoto, zidlala indima ebalulekile kuma-catalytic converters, abalulekile ekunciphiseni ukukhishwa okuyingozi okuvela emkhathini wezimoto. Kodwa-ke, ama-PGM ayivelakancane futhi asatshalaliswa ngokungalingani, futhi ukukhishwa kwawo kuma-ore ayinhloko kuvame ukuba yinkimbinkimbi futhi kuyabiza. Ngenxa yalokho, ukubuyiselwa kwama-PGM emithonjeni yesibili, njenge- Automobile catalysts esetshenzisiwe , kuye kwathola ukunakwa okwandayo. Ukukhishwa kwe- cyanide emazingeni okushisa aphezulu kuvela njengendlela engaba khona yale njongo.

Iqhaza lama-PGM kuma-Automobile Catalysts

Ama-converter e-automobile catalytic aklanyelwe ukuguqula ukungcola okunobuthi kumagesi okukhipha umoya, njenge -Carbon monoxide (CO), ama-hydrocarbon (HC), nama-nitrogen oxides (NOx), abe izinto ezingalimazi kangako njenge-carbon dioxide (CO₂), i-nitrogen (N₂), kanye namanzi (H₂O). Ama-PGM ayizingxenye ezibalulekile ezisebenzayo kula ma-converter. Isibonelo, i-Pt ne-Pd ziyasebenza eku-oxidizeni i-CO₂ kanye ne-HC, kuyilapho i-Rh isetshenziswa kakhulu ekunciphiseni i-NOx. Isidingo sama-PGM embonini yezimoto sikhulu. Ngo-1990, kwasetshenziswa ama-ounces ayizigidi ezingu-1.3 e-platinum, ama-ounces angu-230.000 e-palladium, kanye nama-ounces angu-330.000 e-rhodium ekwakhiweni kwama-catalyst ezimoto. Uma kucatshangelwa ukukhula okuqhubekayo kwemboni yezimoto eminyakeni edlule, inani eliqongelelekayo lama-PGM kuma-catalyst asetshenzisiwe likhulu kakhulu, okwenza abe umthombo wesibili obalulekile.

Izimiso Zokushisa Okuphezulu - I-Cyanide Leaching

I-Cyanide Complexation

I-Cyanide leaching isetshenziswe kakhulu embonini yezimayini, ikakhulukazi ekukhishweni kwegolide. Umgomo ulele ekhonweni lama-ion e-cyanide (CN⁻) ukwenza izakhiwo ezizinzile ngezinsimbi ezithile. Endabeni yama-PGM, ngaphansi kwezinga lokushisa eliphezulu nezimo ezifanele ze-alkaline, i-CN⁻ ingasabela nge-Pt, i-Pd, ne-Rh ukuze yakhe izakhiwo ze-cyanide ezincibilikayo. Lokhu kusabela okuyinkimbinkimbi kuvumela ama-PGMs ukuba ahlakazwe kusukela ku-matrix eqinile ye-catalyst ibe yisisombululo, kube lula ukuhlukaniswa nokuthola izinqubo ezilandelayo.

High - Izithuthukisi Zokushisa

Izimo zokushisa eziphezulu zidlala indima ebalulekile ekukhuthazeni inqubo yokucwilisa. Ukwandisa izinga lokushisa kusheshisa i-kinetics yokusabela. Emazingeni okushisa aphezulu, izinga lokusabalalisa lama-ion e-cyanide ebusweni bezinhlayiya ze-PGM liyakhula, futhi ukusabela kwamakhemikhali kwenzeka ngokushesha okukhulu. Isibonelo, ucwaningo luye lwabonisa ukuthi ekushiseni okuphezulu kwe-cyanide leaching ye-PGMs kusuka ku-catalyst yezimoto, ukuphakamisa izinga lokushisa kusuka ku-100 °C kuya ku-150 °C kungakhuphula kakhulu ukusebenza kahle kwe-Pd ne-Pt. Kodwa-ke, kufanele kuqashelwe ukuthi amazinga okushisa aphakeme kakhulu angase alethe izinselele ezithile, njengokwenyuka kokusetshenziswa kwamandla kanye nokusabela okungenzeka okuseceleni.

Inqubo Yokushisa Okuphezulu - I-Cyanide Leaching yama-Auto Catalysts

Ukwelashwa Kwangaphambili Kwama-Catalysts

Ngaphambi kwenqubo yokukhishwa kwezinga lokushisa eliphezulu kwe-cyanide, ama-catalyst ezimoto asetshenziswayo ngokuvamile adinga ukunakekelwa kusengaphambili. Lesi sinyathelo sibalulekile ukuthuthukisa ukusebenza kahle kwe-leaching. Okokuqala, ama-catalysts achotshozwa ngokomzimba futhi aphansi ukuze kuncishiswe usayizi wezinhlayiyana, okwandisa indawo ethile futhi kudalule ama-PGM amaningi ukuze aphendule. Khona-ke, bangase baphathwe ngokushisa okushisayo, njengokugazinga, ukususa ikhabhoni nokunye ukungcola ebusweni be-catalyst, okwenza ama-PGM afinyeleleke kalula kusixazululo se-cyanide.

Ukusebenza kwe-Leaching

Esigabeni sokukhipha, ama-catalyst alungisiwe ngaphambilini afakwa esitsheni sokusabela esinesixazululo esiqukethe i-cyanide, ngokuvamile i-Sodium Cyanide (NaCN). Isitsha sokusabela sibe sesishiswa ekushiseni okuphezulu okufanele, ngokuvamile esibangeni esingu-120 - 180 °C, bese ingcindezi ilungiswa ngokuya ngezidingo. I-oksijini noma i-oxidizing agent ivame ukungeniswa ukukhuthaza ukucwiliswa kwama-PGM nokuthuthukisa ukusabela kokuhlanganiswa. Isikhathi sokukhipha siyahlukahluka kuye ngokwakheka kwe-catalyst kanye nezimo zokusabela, ngokuvamile kusukela emahoreni amaningana kuya emahoreni angaphezu kweshumi.

Ukwehlukaniswa kanye Nokubuyiswa kwama-PGM

Ngemuva kwenqubo yokukhishwa, isixazululo siqukethe i-PGM encibilikisiwe - i-cyanide complexes. Ukubuyisela ama-PGM, izindlela zokuhlukanisa ezihlukahlukene zingasetshenziswa. Indlela eyodwa evamile iwukukhipha i-solvent, lapho i-extractant ye-organic efanelekile isetshenziswa ngokukhetha ukukhipha ama-PGM otshwaleni be-cyanide leach. Isibonelo, uketshezi oluthile lwe-ionic lubonise ukukhetha okuhle kokuhlukanisa i-Pt ne-Pd kusukela kuphuzo oludakayo. Enye indlela imvula. Ngokulungisa inani le-pH lesixazululo noma ngokungeza ama-ejenti athile angenisa imvula, ama-PGM angancipha aphume esixazululweni ngendlela yosawoti wensimbi noma ama-complexes, angabuye acwengisiswe ukuze kutholwe ama-PGM amsulwa.

Izinzuzo Zokushisa Okuphezulu - I-Cyanide Leaching

High Recovery Ngempumelelo

Uma kuqhathaniswa nezindlela ezithile zendabuko zokubuyisela ama-PGM kuma-catalyst ezimoto, izinga lokushisa eliphezulu le-cyanide leaching lingafinyelela amazinga aphezulu okutakula. Ucwaningo luye lwabonisa ukuthi ngaphansi kwezimo ezithuthukisiwe, amazinga okukhishwa kwe-Pt, Pd, kanye ne-Rh angafinyelela ngaphezu kwama-90%, futhi kwezinye izimo, asondele ku-100%. Isibonelo, ocwaningweni olumayelana nokushisa okuphezulu kwe-cyanide leaching yama-PGM kusuka kuziguquli ezikhathele ze-autocatalytic, i-autoclave leaching ku-150 °C, enomfutho wengxenye ye-oksijini engu-200 psi kanye nesikhathi se-120 min, inikeze> 90% ukuchithwa kwe-PGMs.

Ukukhetha

I-Cyanide inezinga elithile lokukhetha ekuhlanganiseni nama-PGM. Ngaphansi kwezimo ezifanele, ingasabela ngokukhethayo nge-Pt, Pd, kanye ne-Rh kuyilapho inokusebenzelana okuncane nezinye izici eziningi ku-matrix ye-catalyst, njengezingxenye ze-ceramic nezinye izinsimbi eziyisisekelo. Lokhu kukhetha kwenza kube lula inqubo yokuhlukanisa elandelayo futhi kusize ukuthola ama-PGM ngobumsulwa obuphakeme.

Izinselele Nezixazululo

Ubuthi beCyanide

Ukusetshenziswa kwe-cyanide enqubweni ye-leaching kuhlotshaniswa nokukhathazeka okubalulekile kwemvelo nokuphepha ngenxa yobuthi bayo obukhulu. I-Cyanide ingaba yingozi empilweni yomuntu nasendaweni ezungezile uma ingaphathwa ngendlela efanele. Ukubhekana nalolu daba, izinyathelo zokuphepha eziqinile ziyasetshenziswa ohlelweni lwezimboni. Isibonelo, amasistimu we-loop avaliwe aklanyelwe ukunciphisa ukukhululwa kwe-cyanide endaweni. Ukwengeza, ukwelashwa kwe-cyanide - equkethe amanzi angcolile kubalulekile. Ubuchwepheshe obuthuthukisiwe bokuhlanza amanzi angcolile, obufana ne-chemical oxidation nokwelashwa kwebhayoloji, bungasetshenziswa ukubola i-cyanide ibe izinto eziyingozi kancane ngaphambi kokukhipha amanzi angcolile.

Ukusetshenziswa Kwamandla Okuphezulu

Imfuneko yokushisa ephezulu yenqubo iholela ekusetshenzisweni kwamandla okuphezulu. Ukunciphisa le nkinga, kwenziwa imizamo yokwandisa izimo zokusabela. Isibonelo, ngokulawula okunembile kwezinga lokushisa, ukucindezela, nesikhathi sokusabela, okokufaka kwamandla kungancishiswa kuyilapho kugcinwa ukusebenza kahle kokucwiliswa kwamanzi. Ngaphezu kwalokho, ukuthuthukiswa kwemishini yokushisa esebenza kahle kakhulu yamandla kanye nokusetshenziswa kwezinhlelo zokubuyisa ukushisa okulahlwayo nakho kungasiza ekuthuthukiseni ukusebenza kahle kwamandla kwenqubo yokushisa ephezulu ye-cyanide leaching.

Isiphetho

Ukukhuculula i-cyanide emazingeni okushisa aphezulu kubonisa amandla amakhulu okubuyisa izinsimbi eziyigugu , ikakhulukazi ama-PGM, kuma-catalyst ezimoto. Kunikeza ukusebenza kahle kokubuyisela kanye nokukhetha okuphezulu, okubalulekile ekusetshenzisweni kabusha kwezomnotho nokusebenza kahle kwalezi zinsiza eziyigugu. Nakuba kunezinselele ezifana nobuthi be-cyanide kanye nokusetshenziswa kwamandla aphezulu, ucwaningo oluqhubekayo kanye nokusungula izinto ezintsha kwezobuchwepheshe kuyenziwa ukuze kuxazululwe lezi zinkinga. Njengoba isidingo esikhulayo sama-PGM kanye nokugcizelela okwandayo ekusetshenzisweni kabusha kwezinsiza kanye nokuvikelwa kwemvelo, ukukhuculula i-cyanide emazingeni okushisa aphezulu kulindeleke ukuthi kudlale indima ebaluleke kakhulu esikhathini esizayo semboni yokuvuselela kabusha yama-catalyst ezimoto.