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J.a. Johnson - One of the best experts on this subject based on the ideXlab platform.
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Optimisation of nickel extraction from Laterite Ores by high pressure acid leaching with addition of sodium sulphate
Minerals Engineering, 2005Co-Authors: J.a. Johnson, B.c. Cashmore, R.j. HockridgeAbstract:Extraction of nickel from Western Australian Laterite Ores via sulphuric acid leaching at 250 °C has been optimised by the addition of sodium sulphate. Leaching of a nontronitic nickel Laterite Ore in fresh water, with a sulphuric acid loading of 420 kg/t Ore extracted 93% of nickel from the Ore. When limonitic nickel Laterite Ore was leached in fresh water with an acid loading of 310 kg/t Ore, 92% of the total nickel was extracted. The nickel extractions were optimised at 96% for the nontronitic Ore and 95% for the limonitic Ore, at the above acid loadings, when process water sodium ion levels were increased to 4 g/L and 2 g/L, respectively. Further addition of sodium ion resulted in a gradual decrease in overall nickel extraction, as the leach liquor free acidity decreased. At higher acid loadings, the process water sodium ion levels required for optimum extraction were also higher, so as to prevent dissolution of aluminium.
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Pressure acid leaching of arid-region nickel Laterite Ore: Part IV: Effect of acid loading and additives with nontronite Ores
Hydrometallurgy, 2005Co-Authors: J.a. Johnson, R.g. Mcdonald, David M. Muir, J.-p. TranneAbstract:Abstract The extraction of nickel from nontronite-rich Laterite Ores is enhanced by either increasing the acid loading, or the addition of a small amount of sodium to the process water. The results of this study indicate that at least 15% less acid can be used to get the same extraction of nickel from a nontronite-rich Laterite Ore in process water containing 5 g/L sodium ion, compared with the same Ore in fresh process water. In addition, nickel extractions from a second nontronite-rich Laterite Ore were increased by up to 3% compared with fresh water, if process water sodium ion levels is present at 5–11 g/L at a given acid loading of 420 kg/t Ore.
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pressure acid leaching of arid region nickel Laterite Ore part i effect of water quality
Hydrometallurgy, 2003Co-Authors: B I Whittington, J.a. Johnson, R.g. Mcdonald, D M MuirAbstract:The effect of water salinity on the reactions occurring during pressure acid leaching of an arid-region Laterite Ore, using hypersaline water, seawater, sub-potable water and tap water, is examined. Particular emphasis is placed on the mineralogy of the residue and its implications with regard to residue volume/mass, overall acid consumption and nickel extraction. Analysis of a pressure acid leach residue by electron microprobe indicates that the residual nickel is present in phases that contain silicon and varying concentrations of aluminium, but are deficient in sulphur. Incomplete extraction of nickel from the Ore may not be attributed to any one mineral phase.
Lev Filippov - One of the best experts on this subject based on the ideXlab platform.
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Characterization of Weda Bay nickel Laterite Ore from Indonesia
Journal of Geochemical Exploration, 2019Co-Authors: Saeed Farrokhpay, Michel Cathelineau, Simon Blancher, Odile Laugier, Lev FilippovAbstract:The association of fine grained MgeNi silicates with oxy-hydroxides in Laterites and saprolites represents challenges for Ore processing, in particular, in nickel enrichment. The Weda Bay nickel deposit in Indonesia is a typical example of these complex Ores, where clays such as nontronites develop on polyphase serpentinite as protolith. Thus, Ores at Weda Bay have a very fine textured and complex mineralogy, which requires a comprehensive mineralogical identification through the use of a series of different types of analytical approaches (i.e. macroscopic and microscopic methods including SEM equipped with energy dispersive X-ray spectrometry (EDS), Raman spectroscopy, Infrared and X-ray fluOrescence spectroscopy, and QEMSCAN® mapping). Nickel rich saprolites were found to be principally composed of several types of MgeNi serpentines, quartz, clays (nontronite in particular) and little amounts of iron hydroxides. Besides, some parts of the deposit were characterized by the development of nontronites at the interface between the saprolite and the limonite zone. Above this zone, the limonite zone is dominated by iron hydroxides as expected, which replace all earlier silicates including serpentine, and contains a significant amount of nickel. The representative composite Ore sample contains several nickel bearers with variable nickel grade of 2 to 3%. Exceptionally richer phases such as polygonal Fe (Ni)-rich serpentine were also found with nickel grade of 5 to 10%. Serpentine types as well as other newly formed silicates such as Fe-Mg-(Ni) smectites, are intimately mixed, preventing any mineral separation. TherefOre, the only phases which can be separated are quartz and magnetite. This complicates the upgrading of nickel in Weda Bay Laterite Ore.
R.g. Mcdonald - One of the best experts on this subject based on the ideXlab platform.
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Acid resistance of goethite in nickel Laterite Ore from Western Australia. Part I. The relationship between goethite morphologies and acid leaching performance
Hydrometallurgy, 2013Co-Authors: Xiaodong Wang, R.g. Mcdonald, Robert D. Hart, Arie Van RiessenAbstract:Abstract Nickel containing goethite in Laterite Ores shows extreme variability in heap leaching performance. This has been difficult to characterise making utilisation of these Ores for heap leaching problematic. The variability of the leaching performance is demonstrated for selected samples using atmospheric pressure leaching. Quantitative mineralogical analysis based on X-ray diffraction, crystallite morphology from transmission electron microscopy imaging and the chemical composition measured by energy dispersive X-ray spectrometry of the pre- and post-leached Laterite Ore samples suggests acid resistant (slow leaching) goethite is paragenetically interlaced with silica or kaolinite. Caustic digestion is shown to be effective in breaking up cementation frameworks and liberating the goethite interlaced by silica or kaolinite. Large single domain goethite and high chromium substituted goethite are also identified in the slow leaching samples. A better understanding of the microstructure of the acid resistant Laterite Ores is expected to lead to improvement in the hydrometallurgical processing for these Ores.
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Pressure acid leaching of arid-region nickel Laterite Ore: Part IV: Effect of acid loading and additives with nontronite Ores
Hydrometallurgy, 2005Co-Authors: J.a. Johnson, R.g. Mcdonald, David M. Muir, J.-p. TranneAbstract:Abstract The extraction of nickel from nontronite-rich Laterite Ores is enhanced by either increasing the acid loading, or the addition of a small amount of sodium to the process water. The results of this study indicate that at least 15% less acid can be used to get the same extraction of nickel from a nontronite-rich Laterite Ore in process water containing 5 g/L sodium ion, compared with the same Ore in fresh process water. In addition, nickel extractions from a second nontronite-rich Laterite Ore were increased by up to 3% compared with fresh water, if process water sodium ion levels is present at 5–11 g/L at a given acid loading of 420 kg/t Ore.
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pressure acid leaching of arid region nickel Laterite Ore part i effect of water quality
Hydrometallurgy, 2003Co-Authors: B I Whittington, J.a. Johnson, R.g. Mcdonald, D M MuirAbstract:The effect of water salinity on the reactions occurring during pressure acid leaching of an arid-region Laterite Ore, using hypersaline water, seawater, sub-potable water and tap water, is examined. Particular emphasis is placed on the mineralogy of the residue and its implications with regard to residue volume/mass, overall acid consumption and nickel extraction. Analysis of a pressure acid leach residue by electron microprobe indicates that the residual nickel is present in phases that contain silicon and varying concentrations of aluminium, but are deficient in sulphur. Incomplete extraction of nickel from the Ore may not be attributed to any one mineral phase.
Jonas Addaimensah - One of the best experts on this subject based on the ideXlab platform.
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atmospheric acid leaching mechanisms and kinetics and rheological studies of a low grade saprolitic nickel Laterite Ore
Hydrometallurgy, 2016Co-Authors: Jennifer Maccarthy, Ataollah Nosrati, William Skinner, Jonas AddaimensahAbstract:Abstract Improved atmospheric acid leaching (AL) of complex, low grade nickel (Ni) Laterite Ores warrants greater knowledge of the exact processes underpinning Ni and pay metal cobalt (Co) extraction rates, acid consumption and pulp handleability. In this study, the influence of agitation rate (600–1000 rpm) and temperature (70 and 95 °C) on the isothermal, batch acid leaching and rheological behaviour of saprolitic Ni Laterite slurry (40 wt.% solid) was investigated over 4 h at pH 1. The leaching behaviour was distinctly incongruent and reflected strong temperature-dependent Ni/Co extraction, acid consumption and the proliferation of gangue minerals' constituent elements (e.g., Na, Mg, Al, Fe). Whilst the total mass of acid consumed per ton of dry Ore processed was greater at higher temperature, the total kg acid consumed per kg Ni and Co extracted was markedly lower. In all cases, the slurries displayed time-dependent, non-Newtonian, shear thinning rheological behaviour. The pulp viscosities and shear yield stresses were generally greater at lower than at higher temperature, with both increasing dramatically in the course of 4 h leaching. Agitation rate in the range 600–1000 rpm had no noticeable impact on Ni and Co leaching rates, confirming the insignificance of volume diffusion limitation. Although high pulp shear viscosities in the range 37–120 mPa s were observed in the course of leaching, they did not have an impact on Ni and Co leaching mechanisms and kinetics from the saprolitic Laterite Ore. The mechanism of saprolitic Laterite Ore leaching appears to follow a chemical reaction controlled, shrinking cOre model with apparent activation energies of 75.5 ± 3.8 and 81.2 ± 4.1 kJ/mol, respectively, for the release of Ni and Co.
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temperature influence of atmospheric acid leaching behaviour of saprolitic nickel Laterite Ore
Chemeca 2013: Challenging Tomorrow, 2013Co-Authors: Jennifer Maccarthy, Ataollah Nosrati, William Skinner, Jonas AddaimensahAbstract:Atmospheric acid leaching (AL) of low-grade lateritic Ores may encounter serious difficulties due to the presence of high acid consuming serpentinized/clay minerals, leading to pulp gelation and poor mixing, and low value metal recovery. This study investigates the influence of temperature on temporal AL behaviour of saprolitic nickel (Ni) Laterite Ore. Isothermal (70 vs. 95 degreesC), batch, H2SO4 acid leaching studies were performed on 40 wt.% solid dispersions for 4 h at pH 1. The impact of leaching on product particle size, surface area and pulp chemistry and rheology was investigated. At 70 degreesC, the release of < 25 % of Ni and cobalt (Co) into solution, accompanied by incongruent leaching of Mg, Na, Fe, Al, and Si from host gangue mineral phases, was observed. Whilst all the leached species concentrations increased with time, Si concentration which was initially high decreased significantly, presumably due to the formation of secondary mineral species. The slurry's viscosity and shear yield stress increased systematically in the course of leaching, leading to gelation. At 95 degreesC, the percent Ni and Co released increased markedly to 89 and 78 %, respectively, with a very significant increase in concentrations of the other elements except Si, which showed a marked decrease. Higher temperature also led to greater acid consumption rate, particle size reduction with increased specific surface area. For saprolitic Ores, there is the need to enhance processing techniques to improve Ni/Co recovery and reduce acid consumption/pulp gelation.
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drum agglomeration behavior of nickel Laterite Ore effect of process variables
Hydrometallurgy, 2012Co-Authors: Ataollah Nosrati, Jonas Addaimensah, David J. RobinsonAbstract:Abstract Heap leaching is a promising, economically viable processing pathway for extracting nickel (Ni) and cobalt (Co) from complex, low grade Laterite Ores. Producing a stable heap with high permeability and sustainable lixiviant percolation rate is a key requirement to ensure efficient leaching operation for maximum value metal recovery. Agglomeration of fine Ore particles to produce robust granules with desirable attributes (e.g., size distribution and strength and porosity) is a critically important precursor to the heap leaching process. In this study, the effect of binder type/composition and dosage, drum speed, temperature and batch time on drum agglomeration behavior of siliceous goethite (SG) Ni Laterite Ore was investigated. Isothermal, batch agglomeration performed with tap water and 30, 44 and 98%w/w H2SO4 solutions as binders revealed the key role of binder dosage and acidity in controlling Ore particle wettability, granule nucleation and growth behavior. Increasing the binder acidity from zero (tap water) to 30, 44 and 98%w/w H2SO4 led to a higher binder dosage to initiate and maintain a moderate rate of agglomeration. This accordingly reflected decreasing growth rates with increasing binder acidity where 98%w/w H2SO4 resulted in complete suppression of granule growth. At a fixed binder acidity and dosage, both higher temperature and drum speeds led to faster agglomeration rates. The impact of binder acidity and dosage on agglomerates' wet strength appeared to be insignificant. Acid-bound, wet agglomerates' integrity/stability in solution was, however, greater at lower binder dosage and/or binder acidity. The findings foster our understanding of how various, primary process variables may be prudently controlled to produce Ni Laterite agglomerates with desirable properties and behavior, as a key step to enhance heap leaching.
Fangqin Cheng - One of the best experts on this subject based on the ideXlab platform.
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Spinel ferrite transformation for enhanced upgrading nickel grade in Laterite Ore of various types
Minerals Engineering, 2021Co-Authors: Jian-ming Gao, Fangqin ChengAbstract:Abstract Upgrading nickel grade in low-grade nickeliferous Laterite Ores befOre metallurgical extraction process is of utmost importance. However, most of nickel exists mainly in the form of isomorphism in serpentine or goethite, resulting in difficulty in upgrading of nickel by physical separation methods. In this paper, spinel ferrite transformation for enhanced upgrading nickel grade in Laterite Ore of various types was proposed. The mineral phase transformation and migration of valuable metals for various Laterite Ores during calcination process was investigated, as well the influences of mineral phases and chemical compositions on magnetic properties, separation efficiency, and nickel contents in separated Laterite Ore. The results show that spinel nickel ferrite mainly composed of nickel oxide and iron oxide could be completely formed after calcined at 800, 1000 and 900 °C for limonite, saprolite and transition Laterite Ore, respectively. With the increase of calcination temperature, the crystallinity and saturation magnetization Ms value of as-calcined samples become improved, leading to increased nickel recovery, while the nickel content in magnetic fraction is first increased and then slightly decreased. Under the optimum calcination conditions, the nickel recovery for limonite, saprolite and transition Laterite Ore could reach 68.5%, 68.9% and 67.3%, respectively, while the nickel contents in magnetic fraction are 3.01%, 3.23% and 3.15% with increasing by 1.82, 2.27 and 2.11 times, respectively. This paper could provide theOretical basis and technology support for enhanced upgrading of valuable metals from complex associated mineral resources.
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high efficiency leaching of valuable metals from saprolite Laterite Ore using pickling waste liquor for synthesis of spinel type ferrites mfe2o4 with excellent magnetic properties
Journal of materials research and technology, 2021Co-Authors: Jian-ming Gao, Fangqin ChengAbstract:Abstract High-efficiency leaching of valuable metals from nickeliferous Laterite Ore for preparation of functional materials is one of the most important high-value utilization pathways. In this paper, facile preparation of multi-metal spinel-type ferrites (MFe2O4) from saprolite Laterite Ore after pickling waste liquor leaching process was proposed. The effects of pickling waste liquor leaching parameters including acid concentration, leaching temperature and time, liquid–solid ratio and iron ion concentration on leaching efficiency for Fe, Ni, Mg, Mn and Co from saprolite Laterite Ore and the molar ratio (RFe/M) of iron ions to divalent metal ions such as Ni2+, Mn2+, Mg2+, etc. in the leach liquors were systematically investigated. After complete leaching, spinel-type ferrites were synthesized from leach liquors and the influence of RFe/M and pH value as well Zn ion doping on phase compositions, morphological structure and magnetic performance of as-synthesized samples were also characterized and analyzed. Under the optimized leaching conditions, the leaching efficiency of Ni, Co, Mn, Fe and Mg could reach 93.2%, 90.8%, 94.3%, 95.5% and 85.3%, respectively. With the concentration of iron ions in pickling waste liquors increasing from 60 to 160 g·L−1, the RFe/M value increases from 1.88 to 4.32. The pH values for synthesis of spinel-type ferrites with high purity from leach liquors with RFe/M of 1.85 and 2.04 are 8.0 and 11.0, respectively, and the saturation magnetization Ms values of as-synthesized ferrites increase gradually with the increasing of pH value. Zn ions in pickling waste liquors could be doped and fixed in spinel-type ferrites to improve Ms values of as-synthesized ferrites, and the Ms value could reach the highest as 58.6 emu·g−1 when Zn ions doping amount is 0.4. Value-added utilization of pickling waste liquor and saprolite Laterite Ore could be realized by the proposed process. This paper might provide theOretical and technical support for low-cost synthesis of spinel-type ferrites from polymetallic resources.
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facile and large scale fabrication of mg ni fe al 2o4 heterogeneous photo fenton like catalyst from saprolite Laterite Ore for effective removal of organic contaminants
Journal of Hazardous Materials, 2020Co-Authors: Xing Han, Fangqin Cheng, Mei Zhang, Shiye Liu, Xiangtao Huo, Min GuoAbstract:Abstract A facile and cost effective acid leaching-coprecipitation method was developed to prepare spinel-type (Mg,Ni)(Fe,Al)2O4 from saprolite Laterite Ore in large scale. The as-prepared (Mg,Ni)(Fe,Al)2O4 exhibited excellent photo-Fenton-like catalytic activity in decomposing different kinds of organic dyes and antibiotic tetracycline in the present of oxalic acid (H2C2O4). The influential factors of RhB degradation efficiency were investigated, including the (Mg,Ni)(Fe,Al)2O4 dosage, H2C2O4 concentration and the intensity of simulated sunlight. Meanwhile, the reaction mechanism of (Mg,Ni)(Fe,Al)2O4/H2C2O4/simulated sunlight system was also proposed. As the formation of highly photochemical [≡Fe(C2O4)3]3− complex ions on the surface of the (Mg,Ni)(Fe,Al)2O4, the obtained (Mg,Ni)(Fe,Al)2O4 showed degradation efficiency (η) over 90.0 % for common organic dyes and antibiotic tetracycline within 180 min under the optimum conditions. The η and TOC removal for RhB were still over 98.0 % and 46.0 % after five reuse cycles, respectively. The excellent catalytic performance and recyclability make the (Mg,Ni)(Fe,Al)2O4 fabricated from natural saprolite Laterite Ore mOre competitive in dealing with wastewaters contaminated by organic pollutants.
