Daniele La Corte

Recovered ammonia, extracted from waste streams such as industrial leachates and organic waste, represents a unique opportunity to harness a sustainable, carbon-free energy resource. This paper focuses on the energy potential of ammonia recovered from waste, emphasizing its role as a critical element in the transition to a low-carbon economy. Integrating recovered ammonia into energy systems enables industries to reduce dependence on conventional ammonia production, lower greenhouse gas emissions, and advance circular economy practices. The study reviews advanced technologies for recovering ammonia from waste, as well as its application in combustion processes and fuel cells. Particular emphasis is placed on optimizing ammonia combustion to minimize nitrogen oxide (NOx) emissions and on utilizing recovered ammonia in direct ammonia fuel cells and hydrogen generation for fuel cells. Challenges associated with scaling waste recovery technologies and integrating recovered ammonia into existing energy infrastructures are critically examined. By providing an in-depth assessment of the environmental and economic benefits of using recovered ammonia as an energy source, this paper highlights its potential to decarbonize sectors such as transportation, industry, and power generation.

The literature indicates that utilizing pyrometallurgical methods for processing spent LiCoO₂ (LCO) batteries can lead to cobalt recovery in the forms of Co₃O₄, CoO, and Co, while lithium can be retrieved as Li₂O or Li₂CO₃. However, the technology’s high energy consumption has also been noted as a challenge in this recovery process. Recently, an innovative and sustainable approach using microwave (MW) radiation has been proposed as an alternative to traditional pyrometallurgical methods for treating used lithium-ion batteries (LiBs). This method aims to address the shortcomings of the conventional approach. In this study, the treatment of the black mass (BM) from spent LCO batteries is explored for the first time using MW–materials interaction under an air atmosphere. The research reveals that the process can trigger carbothermic reactions. However, MW makes the BM so reactive that it causes rapid heating of the sample in a few minutes, also posing a fire risk. This paper presents and discusses the benefits and potential hazards associated with this novel technology for the recovery of spent LCO batteries and gives information about real samples of BM. The work opens the possibility of using a microwave for raw material recovery in spent LIBs, allowing to obtain rapid and more efficient reactions.

An archaeometallurgical characterization of two iron smelting tap slags recovered from the early medieval site of Ponte di Val Gabbia I (Brescia, northern Italy) was performed. The main goal was to infer from the slags the working conditions of the ancient bloomery furnace in terms of temperature and oxygen chemical potential. The petrology of both slags was investigated by light optical microscopy and scanning electron microscopy, while their chemical compositions were measured via scanning electron microscopy coupled with X-ray dispersive spectroscopy. High-resolution Raman micro-spectrometry was used to confirm the identification of the mineralogical phases. The software Rhyolite-MELTS was used to compute the liquidus temperatures of the two slags, which were found to be 1120 °C and 1146 °C. These temperatures approximate the working temperature of the bloomery furnace. A thermodynamic-based approach was adopted to estimate the redox conditions of the reducing atmosphere of the smelting furnace, revealing that the two slags formed in different redox environments. Specifically, the resulting oxygen chemical potentials were −382.61 kJ/mol and −243.80 kJ/mol at the liquidus temperatures of 1120 °C and 1146 °C, respectively.