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1

Selective flotation separation of chalcopyrite and sphalerite by thermal pretreatment under air atmosphere

Zhou Hepeng, Geng Liang, Zhang Yongbing, Yang Zhizhao, He Kunzhong, Xie Fanxin

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 1

305--314

EN

Thermal pretreatment was performed to enhance the flotation separation of chalcopyrite and sphalerite under the air atmosphere for the first time. Microflotation experiment showed that the floatability of chalcopyrite vanished after thermal pretreatment at above 170℃. By contrast, the floatability of sphalerite was well maintained with a flotation recovery of 90%. In artificial mixed mineral flotation experiments, the separation of sphalerite and chalcopyrite was successfully realized by thermal pretreatment. Results of Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses indicated that the chalcopyrite surface was oxidized dramatically at 170℃, and hydrophilic species such as sulfate (SO42-), oxides (CuO and Fe2O3), and hydroxyl species (Fe(OH)3) were formed on the surface. Hence, the adsorption of potassium butyl xanthate on chalcopyrite decreased significantly after thermal pretreatment. The reason for the higher oxidation speed of chalcopyrite than that of sphalerite was also analyzed.

2

Zinc extraction from Ghazouat leach residues by using jarosite method

Begar Abdelhakim, Djeghlal Mohamed El Amine, Ould Hamou Malek

Mining Science

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2021

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Vol. 28

117--126

EN

In this paper, it was aimed to select and propose a feasible as well as an applicable method, for the extraction of zinc that was present in the disposed GHAZOUAT leach residues having 17.82 wt. % Zn and 20.82 wt. % Fe. After the determination of the components of the residue, the acid leaching was performed to reclaim Zn sequentially. The acid leaching experiments were carried out for Zn extraction by controlling acid concentration, reaction duration and temperature. At the optimum conditions, 240 g/L H2SO4 at 90 °C for 210 min, 80% of initial iron content was removed, and the resultant overall zinc extraction was usually superior than 96%.

3

Raman spectroscopy characterization of some Cu, Fe and Zn sulfides and their relevant surface chemical species for flotation

Vázquez-Sánchez Emmanuel E., Robledo-Cabrera Aurora, Tong Xiong, López-Valdivieso Alejandro

Physicochemical Problems of Mineral Processing

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2020

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Vol. 56, iss. 3

483--492

EN

Raman spectroscopy as a high-resolution characterization technique was used to analyze various pure metal sulfides immersed in water, namely pyrite (FeS2), chalcopyrite (CuFeS2), sphalerite (ZnS), marmatite (Zn1-XFeXS) and galena (PbS). The Raman characterization was undertaken in situ with the minerals immersed in water. Characteristic Raman spectrum that shows the vibrational modes of the atomic bonds in the mineral crystal structure is reported. This spectroscopic technique revealed that marmatite particles are composed of micro-size, perhaps nano-size, zones with different Fe and Zn content. With the intensity of the Fe-S and Zn-S Raman signals, the iron content of the zones was quantified. The copper ion up-take by marmatite particles was studied through this technique. It was found that the up-take of copper ions on the marmatite zones depended on their Fe content. Copper ion up-take occurred more preferentially on the zones of low Fe content than on those of high Fe content. The adsorption of the collector propyl xanthate on pyrite and chalcopyrite was also assessed by Raman spectroscopy. The Raman spectrum revealed that dixanthogen formed on the surface of these sulfides.

4

Density functional theory study of H2O adsorption on different sphalerite surfaces

Deng Zheng-bin, Tong Xiong, Huang Ling-yun, Xie Xian

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 1

82--88

EN

Effects of In, Ge, Fe substitution in the lattice of sphalerite on wettability were usually ignored, therefore the optimal flotation condition could be difficult to find due to lacking of sufficient theoretical study on water adsorption, resulting lower recoveries of different sphalerites. Adsorption of H2O on different sphalerite surfaces was studied using density functional theory (DFT) method. All computational models were built in a vacuum environment to eliminate the effects of oxygen and other factors. H2O molecule prefers to stay with ideal sphalerite, indium-beard sphalerite, germanium-beard sphalerite and marmatite surfaces rather than water. Compared with ideal sphalerite surface, Fe atom improves the hydrophilicity of surface, while In and Ge atoms reduce the hydrophilicity.

5

Quantifying the spreading factor to compare the wetting properties of minerals at molecular level – case study: sphalerite surface

Mohseni M., Abdollahy M., Poursalehi R., Khalesi M. R.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 3

646--656

EN

Spreading of water droplet on sphalerite surface was quantified at molecular level and was utilized for comparison of the wetting properties of sphalerite protonated and hydroxylated surfaces. Molecular dynamic simulations were used to characterize the wetting of sphalerite (110) plane. Experimental contact angles of water droplet on sphalerite surfaces were measured and the results were compared with simulated contact angles to ensure that the simulations are accurate enough for calculation of spreading factors. Shape descriptors such as perimeter, area, Feret’s diameters and circularity were used to characterize the shape of droplet-sphalerite interface at molecular level. Using the shape descriptors, different spreading factors were defined and calculated spreading factors were correlated with simulated contact angle. It was shown that spreading factors which were defined as the volume of water droplet divided by the area and Feret’s diameters, with correlation coefficient of 0.98 and 0.97, can be used as accurate tools for wetting comparison of functionalized sphalerite surface at molecular scale. Proposed approach also can be used for investigations on the effect of surface chemical and physical anisotropies on preferred wetting in specific direction at molecular scales.

6

Interaction between sphalerite and pyrite and its effect on surface oxidation of sphalerite

Yang B., Xie X., Tong X., Lan Z., Cui Y.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 2

311--320

EN

The interaction between sphalerite and pyrite was investigated by dissolution test, X-ray photoelectron spectroscopy (XPS), zeta potential measurement and density functional theory (DFT) calculation. Dissolution tests indicated that sphalerite dissolution was promoted due to the galvanic interaction between sphalerite and pyrite. The Zn2+ ion concentration increased with increasing pyrite content and dissolved time. XPS analysis results demonstrated that a new oxidation product was formed on the sphalerite surface in the presence of pyrite in a pulp. Zeta potential measurements showed that the isoelectric point of sphalerite increased from 3.3 to 5.4 due to galvanic interaction. DFT calculation results suggested that electron transfer from sphalerite to pyrite occurred when they contacted. The Zn 4s and S 3p states of sphalerite lost electrons. The Fe 4p and 4s of pyrite states obtained electrons, and Fe 3d and S 3s states lost a small number of electrons. The surface oxidation of sphalerite was promoted due to the interaction with pyrite, and the collectorless floatability of sphalerite decreased.

7

Copper adsorption reaction rate and ion exchange ratio during the copper activation of sphalerite

Liu J., Luo D., Huang L., Wang Y., Wen S.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 2

377--385

EN

A theoretical analysis method of the solution chemistry characteristic of Cu(II) at various pH values was developed. Using such method, the existence form of Cu species and their proportions in aqueous solution can be clearly determined. After that, the copper adsorption and ion exchange ratio (E) during the copper activation of sphalerite were investigated. The results indicated that the copper activation of sphalerite can be divided into two stages, i.e., the fast activation stage (t ≤4 min) and slow activation stage (t >4 min). The general form of the copper adsorption rate was determined as ΓCu=K1ln(t) +Γ1, which is confirmed by the data fitting of the fast activation stage. The lower activation pH results in higher ion exchange efficiency for Cu substituting Zn. For a strong acid pH of 4.1, the E maintains about 1:1 in the entire activation time range and is not dependent on the activation time. However, the value of E is greater than 1 under weak acidic (pH=6.2) and alkaline (pH=9.1) pH conditions and it significantly depends on the activation time. For such conditions, E decreases with increase in the activation time, which supports the ion exchange mechanism, but within short activation time, it is not a 1:1 ion exchange process.

8

Wpływ struktury związków chemicznych typu (Zn,Fe)S na kinetykę i strukturę produktów procesu ich utleniania

Kulawik S., Michalski R., Kapias P.

Rudy i Metale Nieżelazne Recykling

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2014

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R. 59, nr 4

157--163

PL

Rozpoznanie optymalnych warunków procesu prażenia w warunkach fluidalnych, w zależności od rodzaju stosowanych surowców i ich własności, ma zasadniczy wpływ na własności chemiczne i strukturalne prażonki a tym samym, na uzysk cynku w metodzie hydrometalurgicznej. Aktualnie, światowa produkcja cynku oparta jest na przerobie koncentratów siarczkowych, w których sfaleryty (Zn,Fe)S są dominującym nośnikiem cynku. Przedstawiono preparatykę wytwarzania związku (Zn,Fe)S o różnej zawartości Fe, zbadano podstawowe własności spreparowanych sfalerytów, takie jak: struktura, temperatura zapłonu i kinetyka procesu utleniania. Zbadano własności fizykochemiczne i strukturalne produktów procesu utleniania spreparowanych sfalerytów. Stwierdzono wpływ zawartość żelaza w sfalerytach, oraz wpływ temperatury, na jakość produktów po procesie utleniania. Żelazo po procesie utleniania występuje w postaci trudno ługowanego ferrytu cynku — ZnFe2O4, którego ilość jest zależna od ilości żelaza w prażonym surowcu. Nie stwierdzono istotnego wpływu zawartości żelaza w sfalerycie na kinetykę ich utleniania.

EN

Recognition of optimal roasting conditions in the fluidized bed, depending on used raw materials type and their properties, has a principal influence on chemical and structural properties of roasted ore and yield of zinc, using hydrometallurgical method. Currently, global production of zinc is based on processing of sulfide concentrates, in which (Zn,Fe)S sphalerites are dominant zinc bearing elements. The studies were carried out on the laboratory scale. The paper presents preparation of (Zn,Fe)S with different Fe content and examination of such basic properties of the prepared sphalerites, as: structure, ignition temperature and oxidation kinetics. Physicochemical and structural properties of the products from oxidation process of prepared sphalerites were examined. The influence of iron content in sphalerites and temperature on quality of the products after oxidation was observed. Iron after oxidation has a form of leaching-resistant zinc ferrite — ZnFe2O4 and its quantity depends on iron content in the roasted raw material. No significant impact of iron content in sphalerite on kinetics of their oxidation was observed.

9

Effect of organic matter on the color of sphalerite from the Silesia-Cracow lead-zinc deposits, Poland

Rybicki M.

Contemporary Trends in Geoscience

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2012

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Vol. 1, iss. 1

57--61

EN

Using gas chromatography-mass spectrometry (GC-MS) sphalerite samples from lead and zinc mines of the Silesian-Cracow region were studied in terms of the effect of organic matter on their coloration. The results indicate no correlation between the abundance and chemical composition of organic matter and sphalerite coloration. TOC values for investigated samples are in the range of 0.5-1.28%. A basic feature characterizing all samples is very similar distribution of n-alkanes, with a predominance of short-chain n-alkanes (from n-C13 to n-C21) over long-chain n-alkanes (from n-C25 to n-C35). Among the isoprenoids pristane dominates over phytane (Pr/Ph ratio in one sample is even 8.95), which does not correspond to previous studies (Karwowski et al. 2001) and may be due to the multi-source nature of organic matter present in sphalerite inclusions from the Silesian-Cracow Zn-Pb deposits. The occurrence of hopanes with 17β,21β(H) stereochemistry indicates a low maturity of test samples.

PL

Przy zastosowaniu chromatografii gazowej sprzężonej ze spektrometrią mas (GC-MS) zbadano próbki sfalerytu z kopalń cynku i ołowiu regionu śląsko-krakowskiego pod kątem wpływu materii organicznej na ich barwę. Otrzymane wyniki wskazują na brak korelacji między ilością oraz składem chemicznym materii organicznej a barwą sfalerytu. Wartości TOC dla badanych próbek mieszczą się w przedziale 0.5-1.28%. Charakterystyczną cechą wszystkich próbek jest bardzo zbliżona dystrybucja nalkanów, z wyraźną przewagą n-alkanów krótkołańcuchowych (od n-C13 do n-C21) nad długołańcuchowymi. Wśród izoprenoidów pristan dominuje nad fitanem (stosunek Pr/Ph w jednej próbce wynosi nawet 8.95), co nie odpowiada wynikom poprzednich badań (Karwowski et al. 2001) i może być spowodowane wieloźródłowym charakterem inkluzji materii organicznej w sfalerytach ze śląsko-krakowskich złóż Zn-Pb. Obecność hopanów o strukturze 17β,21β(H) wskazuje na bardzo niską dojrzałość termiczną badanych próbek.

10

Okruszcowanie Pb i Zn w złożu rud miedzi - kopalnia Lubin

Stala-Szlugaj K.

Gospodarka Surowcami Mineralnymi

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2002

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T. 18, z. 3

15-28

PL

W niniejszym artykule, na podstawie badań mineralogicznych i chemicznych podjęto próbę charakterystyki mineralizacji Pb i Zn w złożu rud miedzi, w obrębie kopalni Lubin. Badania przeprowadzono na 39 profilach pionowych do badań mineralogicznych i chemicznych. Próby do badań mineralogicznych pobierane były w taki sposób, aby reprezentowały wszystkie typy skał występujących w badanym fragmencie złoża (tj. piaskowiec, łupek i dolomit), a próby do badań chemicznych - rudę piaskowcową, łupkową i węglanową (n = 124 próby bruzdowe). Podjęto również próbę określenia charakterystyki występowania Pb, Zn i Cu w pobranych profilach pionowych oraz prześledzenia poziomego rozprzestrzenienia ołowiu i cynku w obrębie bilansowego złoża rud miedzi w badanym fragmencie kopalni Lubin.

EN

The study on Pb and Zn mineralization in typical section of copper ore deposit (southern part of the Lubin-Małomice area) are presented in the paper. The samples were collected in 39 vertical profiles, and next have been done the mineralogical and chemical researches. The study samples represented all of the lithological types of rocks, i.e. the sandstone, the Kupferschiefer and the dolomite. The samples for chemical analysis have been collected using channel sampling method, and represent all of the lithological types of copper ores. The sandstone sections were divided into two parts: upper (0.5 m of thickness) and lower (over part). The mineralogical study has proved, that in southern part of the Lubin-Małomice area the copper sulfides are the major Cu-phases, and minor are chalcocite, covellite and digenite. The main Pb and Zn minerals are sphalerite and galena, which in the study are occur occasionally, and the highest concentrations were observed in the Kupferschiefer and in the upper most part at the sandstone. Both, horizontal and vertical distribution of Pb, Zn and Cu were studied in the all collected vertical profiles. In the most of these profiles (80%), the maximal concentration of Pb, Zn and Cu has been observed within the Kupferschiefer ore. The horizontal distribution of Pb and Zn within the sandstone-ore, shale-ore and in economic deposit in researched part of the deposit have also been studied. There were not observed any new rules regulating the distribution of lead and zinc in studied area of copper ore deposit. The lead and zinc concentration are less than 0.01% in the area of more than a half of studied part of the copper ore deposit. However, it was noticed that the areas of highest lead concentrations - >0.36% Pb and zinc concentrations - >0.14% Zn forms the isolated centers, which area are from 0.15 to 2.0 km2 in case of Pb and up to 0.009 km2 in case of Zn.

11

Występowanie cynku i ołowiu w typowym profilu rud miedzi - kopalnia Lubin Wschodni

Stala-Szlugaj K.

Geologia / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

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2001

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T. 27, z. 2--4

435-455

PL

Badaniami objęto typowy fragment złoża rud miedzi, zlokalizowany w obrębie kopalni Lubin Wschodni (pochylnie: E-2 i L-731). Pobrano 35 profili pionowych do badań mineralogicznych oraz chemicznych. W profilach mineralogicznych pobierano próby reprezentujące wszystkie typy litologiczne skał, tj. piaskowiec, łupek i dolomit. Na profile do badań chemicznych złożyły się próby bruzdowe (ciągłe) reprezentujące poszczególne typy litologiczne rudy miedzi (rudę piaskowcową, łupkową i węglanową), przy czym rudę piaskowcową podzielono na część górną (0,5 m) oraz dolną. W pobranych profilach pionowych zbadano rozmieszczenie Zn, Pb i Cu. Oznaczono podstawowe parametry statystyczne zawartości tych metali oraz przedstawiono mapę Zn i Pb w rudzie piaskowcowej, łupkowej oraz w złożu bilansowym w badanym fragmencie złoża.

EN

Typical section of the copper ore deposit (the Lubin Wschodni mine inclines: E-2 and L-731) are discussed in the paper. The samples were collected in 35 vertical profiles, and the mineralogical and chemical researches were done. The samples for mineralogical researches represented all of the lithological types of rocks, i.e. the sandstone, the Kupferschiefer and the dolomite. The samples for chemical researches have been taken by continuous method, and represented all of the lithological types of copper ore (sandstone-ore, shale-ore and carbonate-ore). The sandstone-ore was divided into two parts: upper (0.5 m of thickness) and lower. In such collected vertical profiles were tested the distribution of Zn, Pb and Cu, and also were calculated the basic statistical factors, which characterize the content of these elements. Based on this results, contour maps of Zn and Pb in sandstone-ore, shale-ore and in economic deposit respectively were constructed.

12

Sphalerite-galena aggregates from the Pb-Zn-Ag-Au veins of the Beregovo ore field

Emetz A., Skakun L.

Biuletyn Państwowego Instytutu Geologicznego

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2001

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nr 396

43-44