Kutentha kwambiri kwa cyanidation njira yopezeranso zitsulo zamtengo wapatali kuchokera ku zida zamagalimoto

Introduction

Zitsulo za gulu la Platinum (PGMs), kuphatikizapo platinum (Pt), palladium (Pd), ndi rhodium (Rh), ndizofunikira kwambiri m'mafakitale osiyanasiyana. Mu makampani opanga magalimoto, zimagwira ntchito yofunika kwambiri mu ma catalytic converters, omwe ndi ofunikira pochepetsa mpweya woipa wochokera ku utsi wa magalimoto. Komabe, ma PGM ndi ochepa ndipo amagawidwa mosiyana, ndipo kutulutsa kwawo kuchokera ku miyala yoyambira nthawi zambiri kumakhala kovuta komanso kokwera mtengo. Zotsatira zake, kubwezeretsa ma PGM kuchokera kuzinthu zina, monga ma Automobile catalysts ogwiritsidwa ntchito , kwatchuka kwambiri. Kutulutsa kwa cyanide kutentha kwambiri kukubwera ngati njira yothandiza pa izi.

Udindo wa ma PGM mu Zothandizira Magalimoto

Ma catalytic converters apangidwa kuti asinthe zinthu zoipitsa poizoni mu mpweya wotulutsa utsi, monga Carbon monoxide (CO), hydrocarbons (HC), ndi nitrogen oxides (NOx), kukhala zinthu zosavulaza kwambiri monga carbon dioxide (CO₂), nitrogen (N₂), ndi madzi (H₂O). Ma PGM ndi zigawo zofunika kwambiri mu ma converters awa. Mwachitsanzo, Pt ndi Pd ndi othandiza pa okosijeni CO ndi HC, pomwe Rh imagwiritsidwa ntchito kwambiri pochepetsa NOx. Kufunika kwa ma PGM mumakampani opanga magalimoto kunali kwakukulu. Mu 1990, ma ounces 1.3 miliyoni a platinamu, ma ounces 230.000 a palladium, ndi ma ounces 330.000 a rhodium adagwiritsidwa ntchito popanga ma catalyst a magalimoto. Poganizira kukula kosalekeza kwa makampani opanga magalimoto pazaka zambiri, kuchuluka kwa ma PGM mu ma catalyst ogwiritsidwa ntchito ndi kwakukulu kwambiri, zomwe zimapangitsa kuti akhale chuma chachiwiri chofunikira.

Mfundo Zapamwamba - Kutentha kwa Cyanide Leaching

Cyanide Complexation

Leaching ya cyanide yakhala ikugwiritsidwa ntchito kwambiri m'migodi, makamaka pochotsa golide. Mfundoyi ili mu mphamvu ya ma cyanide ions (CN⁻) kupanga ma complexes okhazikika ndi zitsulo zina. Pankhani ya PGMs, pansi pa kutentha kwambiri ndi nyengo yoyenera ya alkaline, CN⁻ ikhoza kuchitapo kanthu ndi Pt, Pd, ndi Rh kuti apange zitsulo zosungunuka za cyanide. Kusokonezeka kumeneku kumapangitsa kuti ma PGM asungunuke kuchokera ku matrix olimba a chothandizira kuti athetse vutoli, ndikupangitsa kuti apatukane ndi kuchira.

Kutentha Kwambiri - Kupititsa patsogolo Kutentha

Kutentha kwapamwamba kumagwira ntchito yofunika kwambiri polimbikitsa njira yolerera. Kuonjezera kutentha Iyamba Kuthamanga anachita kinetics. Pa kutentha kwakukulu, kufalikira kwa cyanide ions pamwamba pa PGM particles kumawonjezeka, ndipo zotsatira za mankhwala zimachitika mofulumira kwambiri. Mwachitsanzo, kafukufuku wasonyeza kuti kutentha kwambiri kwa cyanide leaching ya PGMs kuchokera ku makina othandizira magalimoto, kukweza kutentha kuchokera ku 100 ° C kufika ku 150 ° C kumatha kuonjezera kwambiri leaching ya Pd ndi Pt. Komabe, ziyenera kudziwidwa kuti kutentha kwambiri kumatha kubweretsanso zovuta zina, monga kuchuluka kwa mphamvu zamagetsi komanso zomwe zingachitike.

Njira Yapamwamba - Kutentha kwa Cyanide Leaching kwa Ma Catalysts a Magalimoto

Kukonzekera kwa Catalysts

Pamaso pa kutentha kwa cyanide leaching process, zothandizira zamagalimoto zomwe zimagwiritsidwa ntchito nthawi zambiri zimafunika kukonzedwa kale. Gawo ili ndilofunika kwambiri kuti muwongolere bwino ntchito ya leaching. Choyamba, chothandizira ndi thupi wosweka ndi pansi kuchepetsa tinthu kukula, amene kumawonjezera enieni padziko ndi kuvumbula zambiri PGMs anachita. Kenaka, amatha kuthandizidwa ndi kutentha, monga kuwotcha, kuchotsa carbon ndi zonyansa zina pamwamba pa chothandizira, zomwe zimapangitsa kuti ma PGM azitha kupeza njira yothetsera cyanide.

Leaching Operation

Mu gawo lotulutsa, ma catalyst omwe adakonzedwa kale amayikidwa mu chotengera choyatsira ndi yankho lokhala ndi cyanide, nthawi zambiri Sodium Cyanide (NaCN). Chotengera choyatsira chimatenthedwa kutentha koyenera, nthawi zambiri pa 120 - 180 °C, ndipo kupanikizika kumasinthidwa malinga ndi zofunikira. Mpweya kapena chothandizira oxidizing nthawi zambiri chimagwiritsidwa ntchito kuti chilimbikitse oxidation ya PGMs ndikuwonjezera complexation reaction. Nthawi yotulutsa imasiyana malinga ndi kapangidwe ka choyatsira ndi momwe zimachitikira, nthawi zambiri kuyambira maola angapo mpaka maola opitilira khumi.

Kupatukana ndi Kubwezeretsanso ma PGM

Pambuyo pa leaching, yankho lili ndi PGM yosungunuka - cyanide complexes. Kuti mubwezeretse ma PGM, njira zosiyanasiyana zolekanitsa zitha kugwiritsidwa ntchito. Njira imodzi yodziwika bwino ndiyo kuchotsa zosungunulira, pomwe chotsitsa choyenera cha organic chimagwiritsidwa ntchito posankha ma PGMs ku mowa wa cyanide leach. Mwachitsanzo, zakumwa zina za ayoni zawonetsa kusankha kwabwino pakulekanitsa Pt ndi Pd ku chakumwa cha leach. Njira ina ndi mvula. Posintha pH ya yankho kapena kuwonjezera zinthu zina zotulutsa mpweya, ma PGM amatha kutulutsidwa munjira ngati mchere wachitsulo kapena ma complexes, omwe amatha kuyengedwanso kuti apeze ma PGM oyera.

Ubwino Wapamwamba - Kutentha kwa Cyanide Leaching

High Kuchira Mwachangu

Poyerekeza ndi njira zachikhalidwe zopezera ma PGM kuchokera ku zida zamagalimoto, kutentha kwambiri kwa cyanide leaching kumatha kuchira kwambiri. Kafukufuku wasonyeza kuti pansi pamikhalidwe yabwino, mitengo ya Pt, Pd, ndi Rh imatha kufika pa 90%, ndipo nthawi zina, pafupifupi 100%. Mwachitsanzo, mu kafukufuku wokhudzana ndi kutentha kwa cyanide leaching ya PGMs kuchokera ku otembenuzidwa otopa, autoclave leaching pa 150 ° C, ndi mpweya wochepa wa mpweya wa 200 psi ndi nthawi ya 120 min, inapereka> 90% PGMs 'kusungunuka.

Kusankha

Cyanide ili ndi gawo lina la kusankha pakuphatikizana ndi ma PGM. Pamikhalidwe yoyenera, imatha kuchitapo kanthu ndi Pt, Pd, ndi Rh kwinaku ikulumikizana pang'ono ndi zinthu zina zambiri mu matrix othandizira, monga zida za ceramic ndi zitsulo zina zoyambira. Kusankha kumeneku kumachepetsa njira yolekanitsa yotsatila ndikuthandizira kupeza ma PGM ndi chiyero chapamwamba.

Mavuto ndi Mayankho

Kuopsa kwa Cyanide

Kugwiritsiridwa ntchito kwa cyanide mu leaching kumagwirizana ndi zovuta zachilengedwe ndi chitetezo chifukwa cha poizoni wake wambiri. Cyanide ikhoza kukhala yovulaza thanzi la munthu komanso chilengedwe ngati sichisamalidwa bwino. Kuti athetse vutoli, njira zotetezera zolimba zimayendetsedwa muzochita zamakampani. Mwachitsanzo, machitidwe otsekedwa - otsekedwa amapangidwa kuti achepetse kutulutsidwa kwa cyanide m'chilengedwe. Kuphatikiza apo, chithandizo cha cyanide - chomwe chili ndi madzi oyipa ndikofunikira. Ukadaulo waukadaulo woyeretsa madzi akuwonongeka, monga oxidation wamankhwala ndi chithandizo chachilengedwe, atha kugwiritsidwa ntchito kuwola cyanide kukhala zinthu zosavulaza kwambiri asanatulutse madzi oyipa.

Kugwiritsa Ntchito Mphamvu Kwambiri

Kufunika kwa kutentha kwakukulu kwa njirayi kumabweretsa kugwiritsa ntchito mphamvu zambiri. Pofuna kuchepetsa vutoli, kuyesayesa kukuchitika kuti akwaniritse zomwe zikuchitika. Mwachitsanzo, pakuwongolera bwino kutentha, kupanikizika, ndi nthawi yochitira, mphamvu zamagetsi zimatha kuchepetsedwa ndikusunga bwino kwambiri. Kuphatikiza apo, kupanga zida zotenthetsera zopangira mphamvu zambiri komanso kugwiritsa ntchito njira zobwezeretsanso zinyalala kungathandizenso kupititsa patsogolo mphamvu zamagetsi pakutentha kwapamwamba kwa cyanide leaching process.

Kutsiliza

Kuchotsa cyanide yochokera ku kutentha kwambiri kukuwonetsa kuthekera kwakukulu kobwezeretsa zitsulo zamtengo wapatali , makamaka ma PGM, kuchokera ku ma catalyst a magalimoto. Kumapereka mphamvu zambiri zobwezeretsa komanso kusankha, zomwe ndizofunikira kwambiri pakubwezeretsanso zinthu zamtengo wapatalizi pazachuma komanso moyenera. Ngakhale kuti pali mavuto monga poizoni wa cyanide ndi kugwiritsa ntchito mphamvu zambiri, kafukufuku wopitilira ndi zatsopano zaukadaulo zikuchitika kuti athetse mavutowa. Chifukwa cha kufunikira kwakukulu kwa ma PGM komanso kugogomezera kwakukulu pakubwezeretsanso zinthu ndi kuteteza chilengedwe, kuchotsa cyanide yochokera ku kutentha kwambiri ikuyembekezeka kukhala ndi gawo lofunika kwambiri mtsogolo mwa makampani obwezeretsanso zinthu zama catalyst a magalimoto.