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Topic Review
Recovery of Palladium from the Spent Automobile Catalysts
The spent automobile catalysts (SAC) is the major secondary source of palladium and the production of SAC is increasing rapidly over years. The price of palladium keeps rising over the years, which demonstrates its preciousness and urgent industrial demand. Recovering palladium from the spent automobile catalysts benefits a lot from economic and environmental protection aspects.  Hydrometallurgical methods such as chloride leaching with oxidants possess a high selectivity of palladium and low consumption of energy, and are cost-effective and flexible for different volume feeds compared with pyrometallurgical methods. The recovery ratios of palladium and other platinum-group metals should be the focus of competition since their prices have been rapidly increased over the years, and hence more efficient extractants with high selectivity of palladium even in the complexed leachate should be proposed in the future. 
  • 1.6K
  • 12 Apr 2022
Topic Review
Primary Rare Earth Elements Resources
Rare earth elements (REEs) are national strategic resources widely applied in industries such as petrochemicals, electronics, national defense and new energy. The primary REE resources are monazite, bastnaesite, xenotime and ion-adsorption type rare earth ore.
  • 157
  • 15 Sep 2023
Topic Review
Potential Challenges to Agronomic Biofortification
Agronomic biofortification is the strategy to enhance the micronutrient contents in the edible parts of food crops through the application of mineral fertilizers. Agronomic biofortification can enrich crops with multiple elements, but the most common ones are Fe, Se, Zn, and I. It may be a suitable approach to reach resource-poor rural populations, provided they have access to chemical fertilizers. Soil-to-plant transfer and the accumulation of minerals in the edible portion of food crops determine the success of biofortification. In addition, the bioavailability of minerals from biofortified crops in the body influences the effectiveness of biofortification programs.
  • 1.5K
  • 07 Nov 2023
Topic Review
Potential Alternative Resources for Rare Earth Elements
Seventeen elements in the periodic table including fifteen lanthanides (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu) and Sc, as well as Y are often collectively referred to as rare earth elements (REE). The depleting REE ores and increasing mining costs are prompting us to consider alternative sources for these valuable metals, particularly from waste streams. Although REE concentrations in most of the alternative resources are lower than current REE ores, some sources including marine sediments, coal ash, and industrial wastes, such as red mud, are emerging as promising with significant concentrations of REE.
  • 391
  • 13 Apr 2023
Topic Review
Platinum Group Elements Geochemistry and Mineralogy
Platinum (Pt), palladium (Pd), rhodium (Rh), iridium (Ir), ruthenium (Ru) and osmium (Os) are known as the platinum group elements (PGE). These metals are characterized by peculiar physical and chemical properties, such as high melting points, resistance to oxidation and corrosion, strong conductivity and ductility. 
  • 1.1K
  • 21 Dec 2022
Topic Review
Plagioclase
Plagioclase is a series of tectosilicate (framework silicate) minerals within the feldspar group. Rather than referring to a particular mineral with a specific chemical composition, plagioclase is a continuous solid solution series, more properly known as the plagioclase feldspar series. This was first shown by the German mineralogist Johann Friedrich Christian Hessel (1796–1872) in 1826. The series ranges from albite to anorthite endmembers (with respective compositions NaAlSi3O8 to CaAl2Si2O8), where sodium and calcium atoms can substitute for each other in the mineral's crystal lattice structure. Plagioclase in hand samples is often identified by its polysynthetic crystal twinning or 'record-groove' effect. Plagioclase is a major constituent mineral in the Earth's crust, and is consequently an important diagnostic tool in petrology for identifying the composition, origin and evolution of igneous rocks. Plagioclase is also a major constituent of rock in the highlands of the Moon. Analysis of thermal emission spectra from the surface of Mars suggests that plagioclase is the most abundant mineral in the crust of Mars. Its name comes from Ancient Greek plágios (πλάγιος 'oblique') + klásis ((κλάσις 'fracture'), in reference to its two cleavage angles.
  • 2.0K
  • 25 Nov 2022
Topic Review
Phosphate Minerals
Phosphate minerals contain the tetrahedrally coordinated phosphate (PO43−) anion along sometimes with arsenate (AsO43−) and vanadate (VO43−) substitutions. Chlorine (Cl−), fluorine (F−), and hydroxide (OH−) anions that also fit into the crystal structure. The phosphate class of minerals is a large and diverse group, however, only a few species are relatively common.
  • 698
  • 14 Nov 2022
Topic Review
Oxide Minerals
The oxide mineral class includes those minerals in which the oxide anion (O2−) is bonded to one or more metal alloys. The hydroxide-bearing minerals are typically included in the oxide class. The minerals with complex anion groups such as the silicates, sulfates, carbonates and phosphates are classed separately. Simple oxides: Hydroxide subgroup:
  • 530
  • 08 Nov 2022
Biography
Orson Anderson
From 1964 to the early 1970s, Orson Anderson led a research program at the Lamont Geological Observatory in the newly-emerging field of “mineral physics”. In collaboration with colleagues Edward Schreiber and Naohiro Soga, Orson exploited the techniques of physical acoustics to study the behavior of the sound velocities of minerals at elevated pressures and temperatures. This research progra
  • 489
  • 27 Sep 2022
Topic Review
Nickel Laterite Deposit
Tectonic emplacement of variably serpentinized ultramafic host rock on land and subsequent chemical weathering under humid tropical to subtropical conditions results in the formation of nickel laterite deposits. Nickel laterites typically occur as weathering mantle over ophiolite complexes, as well as komatiites and layered complexes in Archean to Phanerozoic stable cratonic platforms.
  • 1.5K
  • 01 Apr 2022
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