Sustainable technologies for the recycling and upcycling of precious metals from e-waste.

E-waste is the fastest growing solid waste in the world. Each year, over 50 million tonnes of e-waste are produced, with its rate increasing by 3-5 % annually. Currently, only 17 % of e-waste is properly recycled, leaving the majority managed unsustainably, thereby causing detrimental environmental and economic effects.

A review on the recycling of spent lithium iron phosphate batteries.

Lithium iron phosphate (LFP) batteries have gained widespread recognition for their exceptional thermal stability, remarkable cycling performance, non-toxic attributes, and cost-effectiveness. However, the increased adoption of LFP batteries has led to a surge in spent LFP battery disposal. Improper handling of waste LFP batteries could result in adverse consequences, including environmental degradation and the mismanagement of valuable secondary resources.

A novel process for multi-stage continuous selective leaching of lithium from industrial-grade complicated lithium-ion battery waste.

Lithium-ion batteries are widely used in fields such as electric vehicles, portable electronic devices, energy storage systems, and medical equipment, and their indispensable and irreplaceable characteristics are highly regarded. However, extensive disposal of lithium-ion batteries occurs due to severe electrochemical property degradation. These waste batteries, as high-grade secondary resources, have become exceedingly valuable, especially given their lithium content far exceeding the mineable grade from conventional mining processes.

Direct selective leaching of lithium from industrial-grade black mass of waste lithium-ion batteries containing LiFePO cathodes.

Demand for lithium-ion batteries (LIBs) is projected to maintain unprecedented acceleration for decades, towards satisfying international climate and source objectives. LIB wastes pose a threat to the environment, but also may be considered a strategic, high-grade resource. Yet, recycling the black mass of waste LIBs, which contains plastic, C, Li, Fe, Ni, Co, Mn, Cu, and Al, is very complex.

Adsorption of sulfur on Lanxess Lewatit® AF 5 resin during the acidic albion leaching process for chalcopyrite.

Elemental sulfur is one of the major byproducts of the acidic Albion leaching process for chalcopyrite. It is a challenging component in the leach solution as it impedes gold recovery from the residue. Lanxess Lewatit® AF 5 (AF 5) is a microporous carbon-based resin, which is being investigated for the removal of elemental sulfur during this leaching process.

Thermal treatment of Lanxess Lewatit® AF 5 resin used in the atmospheric chalcopyrite leaching process: Regeneration and sulfur recovery.

Elemental sulfur is a key component in the acidic Albion chalcopyrite atmospheric leaching process and is a challenging issue in the residue. It has been proposed to use Lanxess Lewatit® AF 5 (AF 5) catalyst during the leaching of copper concentrates in the acidic Albion leach process, to eliminate the elemental sulfur from the leach residue. When using AF 5 during leaching, the copper and the iron recoveries were above 95% and 80%, respectively.

Toward Sustainable Solution for Biooxidation of Waste and Refractory Materials Using Neutrophilic and Alkaliphilic Microorganisms-A Review.

The significant increase in economic concern and environmental restrictions has resulted in increasing interest in biotechnological solutions. The application of acidophilic, sulfur-oxidizing microorganisms in biomining and in the treatment of waste matrices has been extensively explored. However, to surmount the current challenges encountered by the industrial use of acidophiles, there is an opportunity for neutrophilic and alkaliphilic microorganisms to be comprehensively considered for the biooxidation of refractory sulfide materials.

Efficient Gold Recovery from Cyanide Solution Using Magnetic Activated Carbon.

Activated carbon has been used for gold recovery in the gold mining industry commercially for decades. The high specific surface area and porosity, good affinity to aurocyanide ions, and abundant resources make activated carbon an efficient and economical material for the adsorption of aurocyanide. However, the separation of activated carbon from the slurry is usually a challenge, and the adsorption rate of activated carbon is limited by the coarse particle size.

Gold Leaching from an Oxide Ore Using Thiocyanate as a Lixiviant: Process Optimization and Kinetics.

Thiocyanate (SCN) is a promising alternative to cyanide as a lixiviant for gold extraction and is 1000 times less toxic than cyanide. In this study, the following leaching parameters were tested to optimize the gold recovery for the first time from an oxide ore using the response surface methodology: initial thiocyanate concentration (10-500 mM), initial Fe concentration (10-500 mM), and pulp density (10-50% w/v). The maximum gold recovery (96%) was achieved with 500 mM thiocyanate, 100 mM Fe, and 50% pulp density at 25 °C and pH = 2 for 24 h.

Leaching characteristics and stability assessment of sequestered arsenic in flue dust based glass.

Arsenic (As), a toxicant, present in flue dust, tailings, and mine drainages generated from mineral processing and smelting processes represents high environmental risk due to its high mobility. Around 42-50% As is found in flue dust in the form of AsO. The vitrification of As results in the formation of stable inert glass material and supposed to reduce the risk of As release to the environment.

Hydrothermal Monodisperse Microspherulite Pyrite: Novel Synthesis Process and Electrochemical Study of Its Oxidation.

A simple one-step hydrothermal method was developed to synthesize pyrite (FeS) sheet- and bulklike pyrite mineral. The Fe/S molar ratio determines the phase of FeS, including pyrite and marcasite. The reaction temperature and time are key factors to regulate the structure, morphology, and size of pyrite.

Green catalytic process for in situ oxidation of Arsenic(III) in concentrated streams using activated carbon and oxygen gas.

Arsenic(III) oxidation is a critical pre-treatment step for overall arsenic immobilization in concentrated industrial arsenic streams. Activated carbon (AC) catalysis is a green, economical and efficient method to oxidize As(III) from waters with high arsenic concentration prior to its removal through precipitation or adsorption. This research investigates AC-catalyzed oxidation process for oxidizing aqueous solutions of As(III) and proposed the possible reaction pathway.

In-situ oxidative arsenic precipitation as scorodite during carbon catalyzed enargite leaching process.

This study explores the in-situ precipitation of scorodite (FeAsO.2HO) during the atmospheric enargite leaching in acid chloride media. The temperature, oxygen sparging rate and the different fractions of the catalyst and ferric ions were the effective parameters on the scorodite precipitation process.