Author
Valeh Aghazadeh
Other affiliations: Tarbiat Modares University
Bio: Valeh Aghazadeh is an academic researcher from Sahand University of Technology. The author has contributed to research in topics: Leaching (metallurgy) & Chalcopyrite. The author has an hindex of 9, co-authored 28 publications receiving 280 citations. Previous affiliations of Valeh Aghazadeh include Tarbiat Modares University.
Papers
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TL;DR: In this paper, pyrite was added to act as a catalyst to enhance the leaching rate of the copper concentrate, and a copper recovery higher than 80% in 24h was achieved at a redox potential of 410mV vs Ag, AgCl, a temperature of 85°C, 15g/L of initial acid concentration, a solid content of 7.8% (w/v), a total initial iron concentration 5 ǫ g/L and pyritic to copper sulphide minerals mass ratio 2:1.
102 citations
TL;DR: This review discusses the recent trends in the research over the last 30 years to use clay minerals in natural and modified forms for removing different toxic organic/inorganic pollutants and shows the importance of modification methods and more extension of novel clay preparation based on nanotechnology which could raise the control of pollution.
Abstract: This review discusses the recent trends in the research over the last 30 years to use clay minerals in natural and modified forms for removing different toxic organic/inorganic pollutants. The natural and modified forms of clay minerals have an exceptional ability to remove different contaminants. However, the modification methods can improve the clay mineral adsorption properties that consequently increase more adsorption sites and functional groups to adsorb different environmental pollutants. This review shows the importance of modification methods and more extension of novel clay preparation based on nanotechnology which could raise the control of pollution. The syntheses of functionalized clays such as pillared clays and porous clay heterostructures introduce the new class of heterostructure materials with high adsorption capacity, capability, and selectivity. Due to the acceptable properties of heterostructure materials including high specific surface area, thermal and mechanical stability, and the existence of multifunctional groups to selective adsorption, this review collects more literature of research related to environmental protection issues. However, it is expected much attention to get a better understanding of the adsorption mechanism, regeneration, and recovery process of these materials.
68 citations
TL;DR: In this paper, pyrite is used as a catalyst of chalcopyrite leaching, and the results showed that maximum copper recovery (more than 95%) is obtained in less than 24 hours, stirring speed of 1150 rpm, pyritic to chal copyrite ratio 4, solution potential 410 mV, temperature 85 °C, and initial sulfuric acid concentration 45 g/L.
Abstract: Chalcopyrite leaching rate in atmospheric pressure and in sulfate media with ferric ion is low because of passive layer formation around chalcopyrite particles. In this investigation pyrite is used as a catalyst of chalcopyrite leaching. Because of galvanic interaction between chalcopyrite and pyrite, the chalcopyrite leaching rate is increased. Effects of parameters such as stirring speed, pyrite to chalcopyrite ratio, solution potential, temperature, and initial acid concentration were investigated. Results showed that maximum copper recovery (more than 95%) is obtained in less than 24 h, stirring speed of 1150 rpm, pyrite to chalcopyrite ratio 4, solution potential 410 mV, temperature 85 °C, and initial sulfuric acid concentration 45 g/L. Also, kinetic investigation showed that chalcopyrite dissolution in the presence of pyrite followed the shrinking core model and the reaction was controlled by the surface reaction. Activation energy (Ea) was calculated at 77.79 kJ/mol. Surface studies showed that in ...
47 citations
TL;DR: The Visual MINTEQ geochemical modeling software was applied to simulate the arsenic species under different pH, temperature and co-existing ions in mine wastewater obtained from dewatering unit in Zarshuran gold mine to investigate the adsorbability of arsenic under synthetic and real alkaline wastewater.
33 citations
TL;DR: In this paper, the textural, structural and surface properties of Al, Fe and Si hierarchical porous nano-bentonite heterostructure (PBH) derivated from Al-Fe pillared nano-branchite (Al, Fe-PILB).
23 citations
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TL;DR: There is general agreement in the literature that chalcopyrite leaching is significantly affected by solution redox potential with an optimum E(h) range suggesting the participation of leach steps that involve both oxidation and reduction.
338 citations
TL;DR: In this paper, the authors provide a fundamental understanding of the various mechanisms involved in microbial leaching of sulfide minerals and provide a brief look at the various factors affecting this process.
135 citations
TL;DR: This study observed the formation of a mechanically 'strong' coating on pyrite that suppressed the mineral's oxidation, and found that As mobility under acidic conditions was limited by its precipitation as ferric arsenate, scorodite, or a Fe/Al arsenate phase, including its strong adsorption to Fe-oxyhydroxides/oxides.
134 citations
TL;DR: In this paper, pyrite was added to act as a catalyst to enhance the leaching rate of the copper concentrate, and a copper recovery higher than 80% in 24h was achieved at a redox potential of 410mV vs Ag, AgCl, a temperature of 85°C, 15g/L of initial acid concentration, a solid content of 7.8% (w/v), a total initial iron concentration 5 ǫ g/L and pyritic to copper sulphide minerals mass ratio 2:1.
102 citations
TL;DR: The differences of mechanisms of the bioleaching and biooxidation on metal sulfides can be more clearly and explicitly understood by summarizing and comparing the two classic minerals, chalcopyrite and pyrite.
83 citations