Valorisation

Recycling large-tonnage copper slag as a secondary source of iron in the form of magnetite is limited by the liberation of finely disseminated phases, whereas particle shape has so far been regarded as a consequence of breakage rather than a controllable feed parameter. In the finite element model, particle contours were taken from optical micrographs, while the third dimension and…

The rapid increase in the production and consumption of electronic and electrical equipment has resulted in a significant global increase in electronic waste (e-waste). This complex waste stream has valuable rare earth elements, precious metals, and base metals, positioning it as an important secondary resource for the recovery of critical metals. With proper extraction and recovery technologies, e-waste presents a…

Hydrogen processing of magnetic scrap (HPMS) is a promising short-loop route for recycling end-of-life NdFeB permanent magnets; however, the resulting hydrogenated powder requires vacuum degassing before reuse. This study defines a phenomenological degassing window for HPMS jet-milled powder from end-of-life wind-turbine magnets by screening degassing temperature (650–900 °C), heating rate (1–3 °C/min), and dwell time (5–60 min) under vacuum. Pressure–temperature…

To address the marked differences in the host phases of phosphorus and vanadium, severe ore sliming, and the difficulty of synergistic recovery from the low-grade phosphorus–vanadium-associated ore in Mazharweina, Xinjiang, process mineralogical analysis, phosphorus flotation condition tests, and acid leaching-solvent extraction tests were conducted to investigate phosphorus and vanadium recovery from this ore. The results showed that the P2O5 and…

Spent lithium-ion battery (LIB) cathodes were investigated as a multimetallic resource for catalyst precursor synthesis. Cathode material was leached under ultrasound using citric or sulfuric acid, with and without H2O2, to compare metal recovery, stability, and thermal transformation. Sulfuric acid with H2O2 achieved the highest extraction efficiencies, with 93.10% Co and 97.15% Mn, while Li extraction exceeded 95%. Maximum sulfuric…

Upcycling of post-consumer aluminum scrap into high-quality wire conductors, such as those used in modern electric vehicle applications, is severely constrained by iron (Fe) accumulation, which may induce wire breakage during high-speed drawing. To define the metallurgical limits for the utilization of secondary 1xxx-series aluminum, this study systematically investigates Fe enrichment behavior, intermetallic phase evolution, and the relationship between phase…

Part 1 of this study identified the recovery of ultrafine particles as the main bottleneck in the decanter centrifuge dewatering of bauxite tailings. This study (Part 2) develops a semi-empirical framework that reconstructs the Whiten partition parameters (corrected cut size d50c, sharpness α, and hydraulic bypass Rf) and the cake solids content from bench-scale characterization, operating and equipment parameters, and…

Platinum group metals (PGMs) are key components of automotive emission-control catalysts, and spent automotive catalysts (SACs) are their main secondary source. This paper reviews hydrometallurgical, pyrometallurgical, magnetic-separation, biometallurgical, and ionic-liquid/deep-eutectic-solvent (IL/DES) routes and compares them for recovery, selectivity, energy demand, reagent hazard, technology readiness, and scalability, using values re-checked against accessible primary sources. Smelting with Cu- or Fe-based collectors is…

The recycling rate of steel across different industry sectors in the United States was calculated using statistical dynamic material flow models, covering the period from 1950 to 2060. Analysis focused on four industry sectors: construction, industrial goods, automotive, and appliances. Findings indicate that steel recycling rates are consistently high across most sectors, reaching approximately 90%. However, the construction sector presents…

The authors invite discussion on the thermodynamic feasibility of the proposed melt chemistry before formal submission.

Reactivity, durability, and standardisation of alkali-activated and geopolymer binders for structural use.