Identification of processes in Cu-ore heap leaching using Cu isotopes and leachate chemistry at Tschudi mine, northern Namibia

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F60460709%3A41210%2F24%3A98433" target="_blank" >RIV/60460709:41210/24:98433 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00025798:_____/24:10169209 RIV/00216208:11310/24:10487035 RIV/61989592:15310/24:73627211

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0304386X24000963" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0304386X24000963</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.hydromet.2024.106356" target="_blank" >10.1016/j.hydromet.2024.106356</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Identification of processes in Cu-ore heap leaching using Cu isotopes and leachate chemistry at Tschudi mine, northern Namibia

Popis výsledku v původním jazyce

Copper isotopic fractionation (in ?65Cu) and leachate characterization were studied in the context of heap leaching at the Tschudi copper mine in northern Namibia. The leached solution is of Mg-SO4 type with high Al and Fe concentrations. The source of Mg and Al in the leachate can be from the alteration of micas such as Mg-bearing muscovite confirmed by X-ray diffraction and scanning electron microscopy; however, the source of Mg cannot be determined with certainty. The principal secondary minerals identified in the leached ore are gypsum and jarosite. The value of pH in leachate is ~1.21 and the concentration of dissolved Cu, occurring mostly as CuSO40 and Cu2+, is about 2 g/L. In comparison with unleached ore (avg. ?65Cu -1.47 ‰), leached ore exhibits lighter isotopic values (avg. ?65Cu -6.01 ‰) with apparent isotopic fractionation ?65Culeached ore-unleached ore of about -4.54 ‰. In contrast, there is isotopic enrichment of leachate in heavier 65Cu isotope (leachate ?65Cu 0.34 ‰) with apparent isotopic fractionation ?65Culeachate-unleached ore value of +1.81 ‰. These results are in good agreement with Cu isotopic fractionation and depletion in heavier 65Cu isotope reported for dissolution experiments in laboratory and groundwater linked to the porphyry copper ore deposits around the world. The leaching of heaps can be considered an analogy of upper part of gossans, but here the supergene enrichment zone is missing due to extremely low pH and oxidizing conditions.

Název v anglickém jazyce

Identification of processes in Cu-ore heap leaching using Cu isotopes and leachate chemistry at Tschudi mine, northern Namibia

Popis výsledku anglicky

Copper isotopic fractionation (in ?65Cu) and leachate characterization were studied in the context of heap leaching at the Tschudi copper mine in northern Namibia. The leached solution is of Mg-SO4 type with high Al and Fe concentrations. The source of Mg and Al in the leachate can be from the alteration of micas such as Mg-bearing muscovite confirmed by X-ray diffraction and scanning electron microscopy; however, the source of Mg cannot be determined with certainty. The principal secondary minerals identified in the leached ore are gypsum and jarosite. The value of pH in leachate is ~1.21 and the concentration of dissolved Cu, occurring mostly as CuSO40 and Cu2+, is about 2 g/L. In comparison with unleached ore (avg. ?65Cu -1.47 ‰), leached ore exhibits lighter isotopic values (avg. ?65Cu -6.01 ‰) with apparent isotopic fractionation ?65Culeached ore-unleached ore of about -4.54 ‰. In contrast, there is isotopic enrichment of leachate in heavier 65Cu isotope (leachate ?65Cu 0.34 ‰) with apparent isotopic fractionation ?65Culeachate-unleached ore value of +1.81 ‰. These results are in good agreement with Cu isotopic fractionation and depletion in heavier 65Cu isotope reported for dissolution experiments in laboratory and groundwater linked to the porphyry copper ore deposits around the world. The leaching of heaps can be considered an analogy of upper part of gossans, but here the supergene enrichment zone is missing due to extremely low pH and oxidizing conditions.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10505 - Geology

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2024

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

HYDROMETALLURGY

ISSN

0304-386X

e-ISSN

0304-386X

Svazek periodika

228

Číslo periodika v rámci svazku

OCT 2024

Stát vydavatele periodika

CZ - Česká republika

Počet stran výsledku

8

Strana od-do

—

Kód UT WoS článku

001268725200001

EID výsledku v databázi Scopus

2-s2.0-85197817592