The Hadamengou gold deposit is located in western part of the northern margin of the North China craton. It is a hydrothermal deposit related to alkaline magmatism. Dissolution of Au, Fe from pyrite and iron oxide （i...The Hadamengou gold deposit is located in western part of the northern margin of the North China craton. It is a hydrothermal deposit related to alkaline magmatism. Dissolution of Au, Fe from pyrite and iron oxide （including magnetite and hematite） individual minerals in the three main types of ore shows： in iron oxides （magnetite and hematite）, Au and Fe were dissolved simultaneously and their solubilities are positively correlated, which means Au is mainly chemical-bonded （lattice gold） and/or colloidal-adsorbed in iron oxides; while in pyrite, on the contrary, Au dissolution obviously lags behind Fe and the solubility of Au shows negative relationship with that of Fe, which indicates Au is mainly hosted as grains of elemental gold （or native gold） within pyrite. Previous studies revealed that the Hadamengou gold deposit is characterized by intensive K-feldspathization and holds high content of iron oxides occasionally replaced by sulfides, which was caused by oxidizing K-enriched alkaline fluids under a stretching geodynamic setting. These geological features, together with the high Au-content in iron oxides, comparable with that of the Olympic Dam deposit in South Australia, suggest that this deposit is the first example of iron oxide-type gold deposits in China.展开更多
The present study deals with the nickel extraction and iron dissolution from nickeliferous laterite by a process of sulfation-roasting-leaching.To optimize the roasting process,response surface methodology(RSM)was uti...The present study deals with the nickel extraction and iron dissolution from nickeliferous laterite by a process of sulfation-roasting-leaching.To optimize the roasting process,response surface methodology(RSM)was utilized which employed two-level and two-factor full factorial central composite design(CCD).The factors of roasting temperature and time were studied. Experiments were carried out for fitting two non-linear regression models of nickel extraction and iron dissolution.Predicted values obtained were close to experimental values,indicating the suitability of the models.Three-dimensional surface plots and contour plot were helpful to predicting the results by performing only limited set of experiments.An area of nickel extraction from 75%to 78% and iron dissolution from 5%to 10%is obtained by an overlaid contour plot.The samples roasted at different temperatures and for different durations were characterized by XRD,which show a good agreement to iron dissolution analysis.展开更多
基金This research was supported by Gold specialties Science Foundation of Finance Ministry （Grant Nos. 22800802039）；Yang Liqin, Niu Cuiyi and Zhao Yinyin are thanked for theirs participation in part of the work for this paper.
文摘The Hadamengou gold deposit is located in western part of the northern margin of the North China craton. It is a hydrothermal deposit related to alkaline magmatism. Dissolution of Au, Fe from pyrite and iron oxide （including magnetite and hematite） individual minerals in the three main types of ore shows： in iron oxides （magnetite and hematite）, Au and Fe were dissolved simultaneously and their solubilities are positively correlated, which means Au is mainly chemical-bonded （lattice gold） and/or colloidal-adsorbed in iron oxides; while in pyrite, on the contrary, Au dissolution obviously lags behind Fe and the solubility of Au shows negative relationship with that of Fe, which indicates Au is mainly hosted as grains of elemental gold （or native gold） within pyrite. Previous studies revealed that the Hadamengou gold deposit is characterized by intensive K-feldspathization and holds high content of iron oxides occasionally replaced by sulfides, which was caused by oxidizing K-enriched alkaline fluids under a stretching geodynamic setting. These geological features, together with the high Au-content in iron oxides, comparable with that of the Olympic Dam deposit in South Australia, suggest that this deposit is the first example of iron oxide-type gold deposits in China.
文摘The present study deals with the nickel extraction and iron dissolution from nickeliferous laterite by a process of sulfation-roasting-leaching.To optimize the roasting process,response surface methodology(RSM)was utilized which employed two-level and two-factor full factorial central composite design(CCD).The factors of roasting temperature and time were studied. Experiments were carried out for fitting two non-linear regression models of nickel extraction and iron dissolution.Predicted values obtained were close to experimental values,indicating the suitability of the models.Three-dimensional surface plots and contour plot were helpful to predicting the results by performing only limited set of experiments.An area of nickel extraction from 75%to 78% and iron dissolution from 5%to 10%is obtained by an overlaid contour plot.The samples roasted at different temperatures and for different durations were characterized by XRD,which show a good agreement to iron dissolution analysis.
