Minerals Engineering最新文献

{"title":"Assessment of a bio-inspired frothing agent derived from Vitamin E in mineral processing","authors":"","doi":"10.1016/j.mineng.2024.108974","DOIUrl":"10.1016/j.mineng.2024.108974","url":null,"abstract":"<div><p>Frothers play a key role in froth flotation by stabilising bubbles, which serve as a platform for separation of minerals of interest. This paper presents D-α-Tocopherol Polyethylene Glycol 6000 Succinate (VitE_PEG6000), an eco-friendly green frother. VitE_PEG6000′s frothing performance was evaluated and benchmarked against MIBC using metrics such as the dynamic and static foam stability index (DFI, SFI), decay rate index (DRI), and critical coalescence concentration (CCC). The results show VitE_PEG6000 offers relatively high DFI of ∼ 405 s/mM and low CCC of ∼ 0.008 mM, classifying it as a powerful frother. Furthermore, NaCl enhances the foaming properties of VitE_PEG6000 by further lowering the surface tension and increasing dilational viscoelasticity. The outcome from this work suggests VitE_PEG6000 as a viable green frother, minimising environmental impact and hazards. Moreover, the compatibility of VitE_PEG6000 with NaCl, as the most dominant salt in groundwater and seawater allows the use of this novel frother with various water sources, thus reducing ecological footprints and fresh water usage.</p></div>","PeriodicalId":18594,"journal":{"name":"Minerals Engineering","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0892687524004035/pdfft?md5=324dec6ba1af6e92d1fd65f344eefb78&pid=1-s2.0-S0892687524004035-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142167832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding the Energy-Saving mechanism of ceramic balls in tumbling mills","authors":"","doi":"10.1016/j.mineng.2024.108982","DOIUrl":"10.1016/j.mineng.2024.108982","url":null,"abstract":"<div><p>This study investigates why ceramic balls achieve superior grinding performance compared to steel balls at lower densities and lower energy consumption. Particle motion analysis shows that increasing the filling level significantly improves the velocity distribution of the grinding media. The energy input from the mill is mainly converted into the kinetic and potential energy of the media, with potential energy being dominant. As the filling level increases, the efficiency of kinetic energy conversion improves. Collisions between media and mineral particles dominate energy transfer, and lower media density enhances collision energy distribution uniformity. Reducing media density decreases grinding energy consumption while maintaining the same grinding effect.</p></div>","PeriodicalId":18594,"journal":{"name":"Minerals Engineering","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142167830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pressure oxidative leaching of chromite in the NaOH-NaNO3-H2O binary sub-molten reaction medium","authors":"","doi":"10.1016/j.mineng.2024.108971","DOIUrl":"10.1016/j.mineng.2024.108971","url":null,"abstract":"<div><p>The liquid-phase oxidation of chromite ore in sub-molten medium is regarded as a clean and efficient method for the preparation of chromate. However, its industrial application is limited by the need for specialized equipment, stringent reaction conditions, and complex chromate-alkali separation processes. To enhance the leaching of chromite and achieve milder reaction conditions, this study introduces a novel NaOH-NaNO₃-H₂O binary sub-molten salt reaction system. Effects of reaction parameters on the leaching ratio of chromium were systematically studied. The results showed that a high chromium extraction rate up to 99 % was obtained within 240 min under the optimal reaction conditions: a reaction temperature of 513.15 K, a NaNO₃-to-ore mass ratio of 0.8:1, an alkaline-to-ore mass ratio of 4:1, an oxygen partial pressure of 2.0 MPa, a stirring speed of 800 rpm, and an alkali concentration of 50 wt%. Kinetics analysis revealed that the leaching process of chromite was controlled by the surface chemical reaction, with an apparent activation energy calculated as 31.58 kJ·mol⁻¹. Moreover, it was also found that the addition of NaNO₃ in the reaction system served a dual role purpose: diluting the viscosity of the reaction medium and acting as an oxygen carrier, which significantly enhanced the leaching efficiency of chromium. Additionally, the binary reaction medium exhibited stable usage performance. During 6 consecutive leaching runs, a chromium leaching rate of around 97 % could be maintained. Therefore, the NaOH-NaNO₃-H₂O binary sub-molten system shows great potential for applications in the highly efficient leaching of chromite ore.</p></div>","PeriodicalId":18594,"journal":{"name":"Minerals Engineering","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142164353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Steel mill solid waste transformation: Optimizing converter sludge recycling through RHF technology","authors":"","doi":"10.1016/j.mineng.2024.108970","DOIUrl":"10.1016/j.mineng.2024.108970","url":null,"abstract":"<div><p>Current methods for treating converter sludge include reintroducing it into the sintering or pelletizing process. However, this method leads to the enrichment of zinc in the blast furnace, which affects the stability of the production operation. To solve this problem, a direct reduction process utilizing multi-solid waste collaborative rotary hearth furnace (RHF) has been implemented in steel plants to recover and safely dispose of valuable components in waste. The laboratory results show that the dezincization rate of the metallized pellets is 99.12 % and the metallization rate is 80.51 % under the premise of reducing 50 °C by calcination at 1200 °C for 15 min in the nitrogen atmosphere. In the industrial test conducted in RHF production line of Shagang from March 2022 to August 2023, the temperature in the high temperature zone was reduced by 50 °C, and the time in the high temperature zone was controlled to 15 min. The industrial test results showed that the residual zinc content in the metallized pellets was 0.63 %, and the metallization rate was about 75.12 %. These particles can be used as feedstock or coolant in the steelmaking process. The average grade of by-product zinc oxide coarse powder can reach 65.88 %, which can be further processed into zinc products with remarkable economic benefit. Through RHF integrated management of converter sludge and other solid waste in steel mills, metallized pellets and high-value products can be produced, which can effectively reduce solid waste in steel enterprises and improve resource utilization.</p></div>","PeriodicalId":18594,"journal":{"name":"Minerals Engineering","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142164352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The relationship between protons and the aqueous oxidation of pyrite by molecular oxygen","authors":"","doi":"10.1016/j.mineng.2024.108968","DOIUrl":"10.1016/j.mineng.2024.108968","url":null,"abstract":"<div><p>The reaction of pyrite (FeS₂) with dissolved oxygen (DO) in acidic media (pH 2.5, 3.0 and 4.0) was studied at 25 °C. In this regard, a series of experimental (potentiodynamic polarization, Electrochemical Impedance Spectroscopy (EIS) or cyclic voltammetry) and theoretical (quantum calculations) approaches were used. It was found that the proton concentration ([H⁺]) has not a significant influence on the oxidative dissolution of FeS₂. The oxidation current density (j_ox) varies little when the pH increases from 2.5 (j_ox = 1.02 μA cm⁻²) to 4.0 (j_ox = 0.80 μA cm⁻²), the order of reaction with respect to [H⁺] being 0.05 ± 0.10. EIS spectra indicate that the pyrite oxidation with dissolved oxygen is controlled by a surface electron transfer reaction. The results of quantum calculations show that protons spontaneously adsorb to the pyrite surface. The density of states of adsorbed protons is located far from Fermi level (between −0.3 and −0.2 Hartree) indicating that they are not available for subsequent reactions. The results of quantum analysis outline the main reasons why protons do not play a discernible role in the oxidation of pyrite with DO and the formation of acid mine drainage.</p></div>","PeriodicalId":18594,"journal":{"name":"Minerals Engineering","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142148357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Utilization of phosphorylated starch as a selective depressant for serpentine in the flotation of nickel sulfide ore","authors":"","doi":"10.1016/j.mineng.2024.108906","DOIUrl":"10.1016/j.mineng.2024.108906","url":null,"abstract":"<div><p>Serpentine is the primary gangue for the flotation enrichment of pentlandite. In this study, phosphorylated starch (PS) was synthesized via the esterification reaction of sodium phosphate with starch and employed as the depressant in separating pentlandite and serpentine through flotation. Micro-flotation results indicated that PS exhibited superior selective depressing effects on serpentine compared to causticized starch (CS). Electrostatic repulsion between pentlandite and serpentine interrupted their hetero-coagulation, as demonstrated by zeta potential measurements and DLVO calculations. Adsorption experiments demonstrated that PS selectively adsorbed onto the serpentine surface rather than on the pentlandite surface. The analysis result of X-ray photoelectron spectroscopy (XPS) and density functional theory calculations (DFT) suggested that PS strongly adsorbed onto the serpentine (magnesium active sites) surface (0<!--> <!-->0<!--> <!-->1) through chelation, forming phospho-oxygen-magnesium (P-O-Mg) bonds, instead of adsorbing on pentlandite. In conclusion, in the flotation process of sulfide ores from serpentine, PS may be regarded as an effective and selective depressant.</p></div>","PeriodicalId":18594,"journal":{"name":"Minerals Engineering","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142230459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrometallurgical recovery of vanadium and calcium from electric arc furnace slag in hydrogen based steelmaking","authors":"","doi":"10.1016/j.mineng.2024.108966","DOIUrl":"10.1016/j.mineng.2024.108966","url":null,"abstract":"<div><p>A two-stage direct leaching method has been applied to selectively recover calcium (Ca) and vanadium (V) from electric arc furnace slag obtained from pilot-scale smelting of hydrogen-reduced iron. Nitric acid-ammonium nitrate-water (HNO₃-NH₄NO₃-H₂O) medium was used in the first stage to produce leachate in which Ca and magnesium (Mg) composed over 99 wt% of the dissolved elements. Sodium carbonate-sodium hydroxide-water (Na₂CO₃-NaOH-H₂O) and ammonium carbonate-water ((NH₄)₂CO₃-H₂O) were investigated as alternative media for the V leaching stage. The effects of the medium composition, temperature, and liquid-to-solid ratio on element recoveries and selectivity were studied for both stages with the aid of experimental designs. Regression models were fitted that could adequately reproduce the general trends in the data and allowed the optimization of the process within the studied variable space. Under optimum conditions, 55 % Ca was recovered with 91 % selectivity. In the subsequent V leaching stage, (NH₄)₂CO₃-H₂O proved to be a more promising medium, achieving V recovery of 39 % and selectivity of 90 % under the optimum conditions.</p></div>","PeriodicalId":18594,"journal":{"name":"Minerals Engineering","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0892687524003959/pdfft?md5=fdbd0dd89b67762ec1c73e196a58a3ea&pid=1-s2.0-S0892687524003959-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142148340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Selective depression of galena in the galena and chalcopyrite system by the Fe(II)-activated persulfate process","authors":"","doi":"10.1016/j.mineng.2024.108969","DOIUrl":"10.1016/j.mineng.2024.108969","url":null,"abstract":"<div><p>The separation of galena (PbS) from chalcopyrite (CuFeS₂) requires strong oxidants for the depression of PbS, due to the excellent hydrophobicity of PbS. In this work, an advanced oxidation process, i.e., S₂O₈²⁻/Fe²⁺ treatment, was employed to selectively depress PbS. The parameters of the S₂O₈²⁻/Fe²⁺ process were determined via flotation tests as follows: pH 3, 1:1 S₂O₈²⁻: Fe²⁺ molar ratio, and 10 min reaction time. The S₂O₈²⁻/Fe²⁺ treatment selectivity decreased the hydrophobicity of the PbS surface. UV–vis spectroscopy results revealed that SO₄^<img>− (major species) and ^<img>OH radicals were produced in solution by the activation of Fe²⁺. The SO₄^<img>−/^<img>OH radicals reacted with the PbS surface, generating the SO₄²⁻ and PbSO₄ species. These species coated the PbS surface, forming a hydrophilic PbS surface and inhibiting the PbS flotation. By contrast, the S₂O₈²⁻/Fe²⁺ treatment generated only a minimal amount of SO₄²⁻ (5.98 % of the total S species) on the CuFeS₂ surface. Therefore, the CuFeS₂ surface was hydrophobic and CuFeS₂ particles could still be floated into the foam phase. This study provides a promising method for the selective depression of PbS in the PbS-CuFeS₂ mixture.</p></div>","PeriodicalId":18594,"journal":{"name":"Minerals Engineering","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142138175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Leaching strategies for the recovery of Co, Ni, Cu and Zn from historical tailings","authors":"","doi":"10.1016/j.mineng.2024.108967","DOIUrl":"10.1016/j.mineng.2024.108967","url":null,"abstract":"<div><p>Energy transition from fossil- to a material-intensive energy system is highly dependent on the availability of Co and Ni. This has increased interest towards non-traditional raw material streams such as mining waste. In this work, leaching experiments were conducted on historical flotation tailings with low concentrations of Co (0.081 wt%), Ni (0.055 wt%), Cu (0.15 wt%) and Zn (0.17 wt%). This low grade may challenge the feasibility of industrial operation, and therefore water, and commonly used mineral acids, were investigated as lixiviants for the process. The electrochemical leaching behaviour was studied using various oxidants (O₂, Cu²⁺, Fe³⁺ and H₂O₂). The results showed that a substantial amount of Co (21 %) and Ni (37 %) could be leached using water, with no additional oxidants or pH adjustment (80 °C, 5 min). In water leaching, the system stabilized inherently to <em>pH</em>=3.7 and the redox potential to <em>E_h</em> &lt; 0.3 V vs Ag/AgCl. This indicates that during the 32–67 years of piling, the weathering conditions had caused natural oxidation of Co– and Ni-bearing minerals such as pyrrhotite and pentlandite. The leaching yields of Co and Ni were slightly increased (5 % units for Co, 10 % units for Ni) by introducing additional acid (1 M) into the leaching system. Further addition of oxidants did not increase the leaching yield of Co, suggesting that the dissolution of Co-bearing minerals followed the chemical leaching mechanism. In contrast, some of the Ni leaching was found to be electrochemical in nature, as extraction increased up to 63 % with the use of strong oxidative (cupric chloride) conditions – most likely due to partial chalcopyrite or pentlandite leaching. Undissolved Co and Ni remained in refractory minerals such as chalcopyrite or pyrite. In addition to Co and Ni, 52 % of Zn and 37 % of Cu were also found to be soluble under acidic conditions. When considering the use of historical flotation tailings as a feed stream in hydrometallurgical processing, direct water leaching may provide an attractive and robust leaching strategy, with spontaneous inherent pH adjustment. An increase in solid-to-liquid ratio or solution circulation (higher acidity) could increase percentual Co and Ni yield and enable enrichment of the target metals in the pregnant leach solution (PLS). If flotation is considered for concentration of Co– and Ni-bearing minerals, water leaching prior to flotation is recommended, to improve both the flotation performance and overall flotation and metal recovery.</p></div>","PeriodicalId":18594,"journal":{"name":"Minerals Engineering","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0892687524003960/pdfft?md5=7011585ad159b26abb68a191f1dd8aae&pid=1-s2.0-S0892687524003960-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142148339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on selective depression of pullulan on specularite/chlorite flotation","authors":"","doi":"10.1016/j.mineng.2024.108972","DOIUrl":"10.1016/j.mineng.2024.108972","url":null,"abstract":"<div><p>The inherent similarities in the physicochemical properties and floatability of specularite and chlorite pose challenges in their effective flotation separation. Exploration and utilization of efficient depressants is vital to improve the flotation separation performance. In this study, pullulan gum (PG) was employed as a depressant in the flotation separation of specularite and chlorite, employing dodecylamine (DDA) as a collector. PG’s inhibitory impact on the flotation performances of these minerals was evaluated through extensive flotation tests and systematically explored its inhibiting mechanism via various surface analytical measurements. Flotation experiments revealed that PG significantly depressed the floatability of specularite while exerting minimal effect on chlorite. Zeta potential tests and surface wettability analyses illustrated strong adherence of PG to specularite, hindering subsequent DDA adsorption, while its impact on DDA adsorption onto chlorite was negligible. Additionally, adsorption capacity measurements confirmed markedly higher PG adsorption onto specularite than chlorite. Further analyses via Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), and density functional theory (DFT) calculations indicated weak adsorption of PG on chlorite, contrasting with strong chemical adhesion observed between PG and specularite. This disparity resulted in distinct flotation behaviors of these minerals. Consequently, selective depression of specularite flotation and effective flotation separation from chlorite were achieved. Thus, PG emerges as an efficient and eco-friendly depressant, showcasing promise in enabling the flotation-based separation of specularite and chlorite.</p></div>","PeriodicalId":18594,"journal":{"name":"Minerals Engineering","volume":null,"pages":null},"PeriodicalIF":4.9,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142148356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}