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Electronic waste (e-waste) is one of the fastest-growing waste streams in the world and Europe is classified as the first producer in terms of per capita amount. To reduce the environmental impact of e-waste, it is important to recycle it. This work shows the possibility of reusing glassy substrates, derived from the MW-assisted acidic leaching of Waste Printed Circuit Boards (WPCBs), as an adsorbent material. The results revealed an excellent adsorption capability against methylene blue (MB; aqueous solutions in the concentration range 10 -5 M-2 × 10 -5 M, at pH = 7.5). Comparisons were performed with reference samples such as activated carbons (ACs), the adsorbent mostly used at the industrial level; untreated PCB samples; and ground glass slides. The obtained results show that MW-treated WPCB powder outperformed both ground glass and ground untreated PCBs in MB adsorption, almost matching AC adsorption. The use of this new adsorbent obtained through the valorization of e-waste offers advantages not only in terms of cost but also in terms of environmental sustainability.

The carbonation of alkaline industrial wastes is a pressing issue that is aimed at reducing CO 2 emissions while promoting a circular economy. In this study, we explored the direct aqueous carbonation of steel slag and cement kiln dust in a newly developed pressurized reactor that operated at 15 bar. The goal was to identify the optimal reaction conditions and the most promising by-products that can be reused in their carbonated form, particularly in the construction industry. We proposed a novel, synergistic strategy for managing industrial waste and reducing the use of virgin raw materials among industries located in Lombardy, Italy, specifically Bergamo-Brescia. Our initial findings are highly promising, with argon oxygen decarburization (AOD) slag and black slag (sample 3) producing the best results (70 g CO 2 /kg slag and 76 g CO 2 /kg slag, respectively) compared with the other samples. Cement kiln dust (CKD) yielded 48 g CO 2 /kg CKD. We showed that the high concentration of CaO in the waste facilitated carbonation, while the presence of Fe compounds in large amounts caused the material to be less soluble in water, affecting the homogeneity of the slurry.

There are several recycling methods to treat discharged lithium-ion batteries, mostly based on pyrometallurgical and hydrometallurgical approaches. Some of them are promising, showing high recovery efficiency (over 90%) of strategic metals such as lithium, cobalt, and nickel. However, technological efficiency must also consider the processes sustainability in terms of environmental impact. In this study, some recycling processes of spent lithium-ion batteries were considered, and their sustainability was evaluated based on the ESCAPE "Evaluation of Sustainability of material substitution using CArbon footPrint by a simplifiEd approach" approach, which is a screening tool preliminary to the Life Cycle Assessment (LCA). The work specifically focuses on cobalt recovery comparing the sustainability of using inorganic or organic acid for the leaching of waste derived from lithium-ion batteries. Based on the possibility to compare different processes, for the first time, some considerations about technologies optimization have been done, allowing proposing strategies able to save chemicals. In addition, the energy mix of each country, to generate electricity has been considered, showing its influence on the sustainability evaluation. This allows distinguishing the countries using more low-carbon sources (nuclear and renewables) for a share of the electricity mix, where the recycling processes result more sustainable. Finally, this outcome is reflected by another indicator, the eco-cost from the virtual pollution model 99' proposed by Vogtländer, which integrates the monetary estimation of carbon footprint.

The COVID-19 pandemic suddenly changed the lifestyle of billions of people. Face masks became indispensable to protect from the contagion providing a significant environmental impact. The aim of this work is to propose possible solutions to decrease masks' impact on the environment. For this reason, different masks (surgical and fabric) were considered, and the CO 2 emissions associated with the mask materials production were calculated. Carbon Footprint (CF) for each material composing the masks was evaluated through the database Ces Selector 2019. The software Qgis (version 2.18.20) allows us to elaborate the CO 2 emissions maps for each Italian region. Finally, for surgical masks, which are often imported from abroad, the CF related to transport was considered. It results that fabric masks are a sustainable solution to prevent contagion. The total CO 2 emission associated with the use of fabric masks from the beginning of the pandemic (March 2020) to December 2021 resulted in about 7 kton compared to 350 kton for surgical masks.

Phosphate rocks are a critical resource for the European Union, and alternative sources to assure the future production of a new generation of fertilizers are to be assessed. In this study, a statistical approach, combined with a sustainability evaluation for the recovery of materials from waste containing phosphorus (P), is presented. This work proposes a strategy to recover P and silica (SiO 2 ) from rice husk poultry litter ash (RHPLA). The design of experiment (DoE) method was applied to maximize the P extraction using hydrochloric acid (HCl), with the aim to minimize the contamination that can occur by leachable heavy metals present in RHPLA, such as zinc (Zn). Two independent variables, the molar concentration of the acid, and the liquid-to-solid ratio (L/S) between the acid and RHPLA, were used in the experimental design to optimize the operating parameters. The statistical analysis showed that a HCl concentration of 0.34 mol/L and an L/S ratio of 50 are the best conditions to recover P with low Zn contamination. Concerning the SiO 2 , its content in RHPLA is too low to consider the proposed recovery process as advantageous. However, based on our analysis, this process should be sustainable to recover SiO 2 when its content in the starting materials is more than 80%.

The Sustainable Development Goals (SDGs) have been proposed to give a possible future to humankind. Due to the multidimensional characteristic of sustainability, SDGs need research activities with a multidisciplinary approach. This work aims to provide a critical review of the results concerning sustainable materials obtained by Italian researchers affiliated to the National Interuniversity Consortium of Materials Science and Technology (INSTM) and their contribution to reaching specific indicators of the 17 SDGs. Data were exposed by using the Web of Science (WoS) database. In the investigated period (from 2016 to 2020), 333 works about sustainable materials are found and grouped in one of the following categories: chemicals (33%), composites (11%), novel materials for pollutants sequestration (8%), bio-based and food-based materials (10%), materials for green building (8%), and materials for energy (29%). This review contributes to increasing the awareness of several of the issues concerning sustainable materials but also to encouraging the researchers to focus on SDGs' interconnections. Indeed, the mapping of the achievements can be relevant to the decision-makers to identify the opportunities that materials can offer to achieve the final goals. In this frame, a "Sustainable Materials Partnership for SDGs" is envisaged for more suitable resource management in the future.

This work proposes new eco-materials for the adsorption of diclofenac (DCF). The large consumption of this nonsteroidal anti-inflammatory drug combined with the inefficiency of wastewater treatment plants (WWTPs) leads to its presence in aquatic environments as an emerging pollutant. The adsorption technique is widely used for pharmaceutical removal. Moreover, due to the large effect of commercial adsorbents, in the frame of the Azure Chemistry approach, new sustainable materials are mandatory for removal as emerging pollutants. The work proposes three adsorbents that were obtained from different stabilization methods of fly ash derived from an incinerator plant; the stabilization techniques involved the use of various industrial by-products such as bottom ash, flue gas desulphurization residues, coal fly ash, and silica fume. The best performance, although less than activated carbon, was obtained by COSMOS (COlloidal Silica Medium to Obtain Safe inert: the case of incinerator fly ash), with a removal efficacy of approximately 76% with 15 g/L of material. Several advantages are expected not only from the DCF removal but also from an economic perspective (the newly obtained adsorbents are eco-materials, so they are cheaper in comparison to conventional adsorbents) and in terms of sustainability (no toxic reagents and no heating treatment are involved). This work highlights the adsorption performance of the new eco-materials and their potential use in WWTPs.

Valorisation of the urban plastic waste in high-quality recyclates is an imperative challenge in the new paradigm of the circular economy. In this scenario, a key role in the improvement of the recycling process is exerted by the optimization of waste sorting. In spite of the enormous developments achieved in the field of automated sorting systems, the quest for the reduction of cross-contamination of incompatible polymers as well as a rapid and punctual sorting of the unmatched polymers has not been sufficiently developed. In this paper, we demonstrate that a miniaturized handheld near-infrared (NIR) spectrometer can be used to successfully fingerprint and classify different plastic polymers. The investigated urban plastic waste comprised polyethylene (PE), polypropylene (PP), poly(vinyl chloride) (PVC), poly(ethylene terephthalate) (PET), and poly(styrene) (PS), collected directly in a recycling plastic waste plant, without any kind of sample washing or treatment. The application of unsupervised and supervised chemometric tools such as principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) on the NIR dataset resulted in a complete classification of the polymer classes. In addition, several kinds of PET (clear, blue, coloured, opaque, and boxes) were correctly classified as PET class, and PE samples with different branching degrees were properly separated.

Mineral carbonation, involving reactions of alkaline earth oxides with CO 2, has received great attention, as a potential carbon dioxide sequestration technology. Indeed, once converted into mineral carbonate, CO 2 can be permanently stored in an inert phase. Several studies have been focalized to the utilization of industrial waste as a feedstock and the reuse of some by-products as possible materials for the carbonation reactions. In this work municipal solid waste incineration fly ash and other ashes, as bottom ash, coal fly ash, flue gas desulphurization residues, and silica fume, are stabilized by low-cost technologies. In this context, the CO 2 is used as a raw material to favor the chemical stabilization of the wastes, by taking advantage of the pH reduction. Four different stabilization treatments at room temperature are performed and the carbonation reaction evaluated for three months. The crystalline calcium carbonate phase was quantified by the Rietveld analysis of X-ray diffraction (XRD) patterns. Results highlight that the proposed stabilization strategy promotes CO 2 sequestration, with the formation of different calcium carbonate phases, depending on the wastes. This new sustainable and promising technology can be an alternative to more onerous mineral carbonation processes for the carbon dioxide sequestration.

A new technology was recently developed for municipal solid waste incineration (MSWI) fly ash stabilization, based on the employment of all waste and byproduct materials. In particular, the proposed method is based on the use of amorphous silica contained in rice husk ash (RHA), an agricultural byproduct material (COSMOS-RICE project). The obtained final inert can be applied in several applications to produce "green composites". In this work, for the first time, a process for pre-treatment of rice husk, before its use in the stabilization of heavy metals, based on the employment of Instant Pressure Drop technology (DIC) was tested. The aim of this work is to verify the influence of the pre-treatment on the efficiency on heavy metals stabilization in the COSMOS-RICE technology. DIC technique is based on a thermomechanical effect induced by an abrupt transition from high steam pressure to a vacuum, to produce changes in the material. Two different DIC pre-treatments were selected and thermal annealing at different temperatures were performed on rice husk. The resulting RHAs were employed to obtain COSMOS-RICE samples, and the stabilization procedure was tested on the MSWI fly ash. In the frame of this work, some thermal treatments were also realized in O2-limiting conditions, to test the effect of charcoal obtained from RHA on the stabilization procedure. The results of this work show that the application of DIC technology into existing treatment cycles of some waste materials should be investigated in more details to offer the possibility to stabilize and reuse waste.

This paper reports the results on the use of an innovative inert, based on stabilized fly ash from municipal solid waste incineration as a filler for polypropylene. The starting material, which contains large quantities of leachable Pb and Zn, was stabilized by means of an innovative process using rice husk ash as a waste silica source, together with other fly ashes, such as coal fly ash and flue gas desulfurization residues. The use of all waste materials to obtain a new filler makes the proposed technology extremely sustainable and competitive. The new composites, obtained by using the stabilized material as a filler for polypropylene, were characterized and their mechanical properties were also investigated. A comparison with a traditional polypropylene and calcium carbonate based compound was also done. This research activity was realized in the frame of the COSMOS-RICE project, financed by the EU Commission.