101 research outputs found
Cleaner metallurgical industry in Serbia: a road to the sustainable development
Since the sustainable development has been a global and fundamental objecttive, a metallurgical industrial sector faces some of the most difficult sustainability challenges of any industrial sector. On the other hand, the metallurgical production in Serbia is a very important part of the economy. Due to present facilities and technologies, metallurgical companies face a great challenge to fulfill the requirements introduced by legislature referring to the cleaner production and sustainable development. The state of art in the production, facilities, pollution with some answers to imposed challenges is presented
Towards sustainable processing of columbite group minerals: elucidating the relation between dielectric properties and physico-chemical transformations in the mineral phase
Current methodologies for the extraction of tantalum and niobium pose a serious threat to human beings and the environment due to the use of hydrofluoric acid (HF). Niobium and tantalum metal powders and pentoxides are widely used for energy efficient devices and components. However, the current processing methods for niobium and tantalum metals and oxides are energy inefficient. This dichotomy between materials use for energy applications and their inefficient processing is the main motivation for exploring a new methodology for the extraction of these two oxides, investigating the microwave absorption properties of the reaction products formed during the alkali roasting of niobium-tantalum bearing minerals with sodium bicarbonate. The experimental findings from dielectric measurement at elevated temperatures demonstrate an exponential increase in the values of the dielectric properties as a result of the formation of NaNbO3-NaTaO3solid solutions at temperatures above 700 °C. The investigation of the evolution of the dielectric properties during the roasting reaction is a key feature in underpinning the mechanism for designing a new microwave assisted high-temperature process for the selective separation of niobium and tantalum oxides from the remainder mineral crystalline lattice
Role of boehmite/solution interface in boehmite precipitation from supersaturated sodium aluminate solutions
Differential precipitation of copper and nickel from acidic polymetallic aqueous solutions
Effect of synthesis parameters on precipitation of nanocrystalline boehmite from aluminate solutions
Thermodynamic determination of the stability area of boehmite in Al2O3-Na2O-H2O and Al2O3-H2O systems
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