A Recycling Alternative for Expanded Polystyrene Residues Using Natural Esters

The objective of this research is to provide a new recycling method for one of the most consumed plastics today, since it is used for the manufacture of a wide variety of industrial products, which leads to an environmental problem caused by incorrect handling and final disposal.The dissolution of expanded polystyrene waste (WEP) was evaluated by using natural esters for its post treatment and recovery. The use of omega-3 as a natural solvent creates an opportunity to take advantage of natural biomass, since it can be obtained from the residues from the fishing activity, this being an economic advantage for obtaining raw material and also friendly with the environment.For the development of this research, expanded polystyrene containers were used, as well as omega-3 and glyceryl tributyrate as natural solvents and ethyl butyrate as synthetic solvent, methanol and isopropanol for recovery and cleaning of the polystyrene. The characterization of the recovered material was carried out with thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and infrared spectroscopy (FTIR) techniques. The experimental data obtained indicated that the use of these esters is a good alternative for the recycling of expanded polystyrene.

Material Flux through an Innovative Recycling Process Treating Different Types of End-of-Life Photovoltaic Panels: Demonstration at Pilot Scale

A quantitative assessment of the material flux emerging from a pilot plant for the treatment of end-of-life photovoltaic panel waste was reported. The process included the manual dismantling of aluminum frames, mechanical treatment for size reduction, and the physical treatment of the milled materials for the release of coarse glass from the encapsulant polymer. Demonstration activities were performed using 1 ton of Si-, 1 ton of CdTe-, and 1 ton of CIGS-based photovoltaic panels (investigated separately), confirming the ability of the process to treat different photovoltaic technologies. The characterization of the input materials was performed and compared with previous literature data. The major bottleneck in the definition of an effective process option for the treatment of different panel technologies was emphasized by the high heterogeneity reported. Mass balances for the proposed process were derived by the recovered material flow. It was highlighted that in processes based on mechanical treatments, producing predominantly coarse fractions allows for the facile separation of most of the valuable components. In this perspective, the present work offers further insights into the design of recycling process to reach increased profitability/sustainability, especially considering the distributions of valuable metals in the process products.

Review of Achieved Purities after Li-ion Batteries Hydrometallurgical Treatment and Impurities Effects on the Cathode Performance

This paper is a product purity study of recycled Li-ion batteries with a focus on hydrometallurgical recycling processes. Firstly, a brief description of the current recycling status was presented based on the research data. Moreover, this work presented the influence of impurities such as Cu, Fe and Mg on recovered cathode materials performance. The impact of the impurities was described depending on their form (metallic or ionic) and concentration. This work also reviewed hydrometallurgical recycling processes depending on the recovered material, obtained purity and recovery methods. This purity data were obtained from both research and battery industry actors. Finally, the purity study was completed by collecting data regarding commercial battery-grade chemical compounds and active lithium cathode materials, including required purity levels and allowed impurity limitations.

Using Graphene Oxide Based Materials for Thermal Sorption

In this work, some nanocomposite materials based on graphene oxide (GO) (Al2O3/GO, Fe3O4/GO, Fe3O4–Al2O3/GO) were prepared and characterized by X-ray and infrared spectra, SEM and EDX analysis. GO based materials were dispersed into salty water and the thermal absorption ability of mixtures was measured. Results showed that thermal sorption of composite materials was greater than that of single materials. Fe3O4-Al2O3/GO gives the highest thermal absorption efficiency (the temperature difference between the blank sample and the sample containing Fe3O4-Al2O3/GO with content of 0.5 mg/mL is 6°C). The influence of the material content in salty water on the thermal sorption efficiency was investigated and a suitable concentration of 0.5 mg/mL was found. 98% of Fe3O4-Al2O3/GO was recovered with the magnet because of its magnetic property and thermal absorption of recovered material are similar to that of the fresh material. The research results show the potential of using these nanocomposite materials to increase the efficiency of thermal sorption in the process of distilling salty water into fresh water.

Serpentinite Mud Volcanism and Exhumation of Forearc- and Lower Plate Material in the Mariana Convergent Margin System (IODP Expedition 366)

<p>Serpentine seamounts located in the forearc region of a subduction zone represent an excellent natural laboratory for studying the geochemical processes acting along convergent plate margins as well as the forearc structure and the related fault patterns. Active serpentinite mud volcanoes are currently restricted only to the Izu-Bonin-Mariana system, where old (presumably Cretaceous) oceanic lithosphere is subducting in the absence of an accretionary prism.</p><p>IODP Expedition 366 recovered cores from three serpentinite mud volcanoes at increasing distances from the Mariana trench (Yinazao, Fantangisña and Asùt Tesoro). Most of the material consists of serpentinite mud containing lithic clasts from the underlying forearc crust and mantle as well as from the subducting Pacific plate. Pelagic sediments and volcanic ash deposits underlying the mud volcanoes were also recovered. Recycled materials from the subducted slab are found at all three mud volcanoes and consist of metavolcanics, metamorphosed pelagic sediments including cherty limestone as well as fault rocks.</p><p>Preliminary investigation of lithic clasts from the furthest Asùt Tesoro Seamount revealed metavolcanics as well as serpentinized ultramafics with well-preserved primary mineral assemblages containing olivine, orthopyroxene and spinel.</p><p>Recovered clasts from the summit of the adjacent Fantangisña Seamount contain mainly sedimentary rocks of probable Pacific plate provenance. These consist of red cherty limestone breccia, red shale and mud-siltstone transected by a network of carbonate veins. In contrast, recovered material from the flank shows a wider variety including ultramafic rocks with various degrees of serpentinization and matrix composed of mesh and bastite textures, mafic metavolcanics as well as low-grade metasediments (cherty limestones). Interestingly, garnet with andradite composition occurs throughout the matrix of the ultramafics, indicating serpentinization temperatures of at least 225 °C.</p><p>Petrological analysis of metabasalt clasts from the flank of Fantangisña shows changes in the mineral composition within the different core intervals. The composition of clinopyroxene varies between aegirine-augite and omphacite, but augite and diopside are also present. The presence of phengite with Si content of up to 3.5 a.p.f.u. as well as the Na-content in pyroxene indicate minimum pressure of 0.7 GPa at ~250 °C. Additionaly, this estimation is supported by the presence of prehnite, chlorite and pumpellyite. </p><p>Furthermore, providing a detailed characterization of the fluids composition and transport would allow the better constraining of the tectonic and metamorphic history as well as the physical properties of the subducting Pacific Plate. Additional data on that will be presented.</p>

Characterization of K6Ta10.8O30 Microrods with Tetragonal Tungsten Bronze-Like Structure Obtained from Tailings from the Penouta Sn-Ta-Nb Deposit

In this work, a deep characterization of the properties of K6Ta10.8O30 microrods has been performed. The starting material used to grow the microrods has been recovered from mining tailings coming from the Penouta Sn-Ta-Nb deposit, located in the north of Spain. The recovered material has been submitted to a thermal treatment to grow the microrods. Then, they have been characterized by scanning electron microscopy, X-ray diffraction, micro-Raman and micro-photoluminescence. The results of our study confirm that the K6Ta10.8O30 microrods have a tetragonal tungsten bronze-like crystal structure, which can be useful for ion-batteries and photocatalysis.

Crossroads and Barriers on the Roman Border: Institutional Authority, Roman Heritage and the “Đerdap” Projects

Institutional authority, Roman heritage and the “Đerdap” projects Although “the archaeological research in the Đerdap area represents the most important crossroad in Serbian archaeology” (Bikić i Šarić 2017, 67), the role of the two large research projects Đerdap I and II in the development of the discipline and the local archaeological community remains to be thoroughly reconsidered. In search for the answer whether the vast corpus of archaeological material and information gained in the course of these projects influenced the shift in interpretation of the Roman past and in presentation of the Roman frontier on the Danube, the paper presents certain scientific and research aspects and the consequences of the projects for the interpretive framework of the Roman period. It may be expected that, just as the fieldwork itself was a large opportunity for professional training and growing, the huge amount of information on the Roman border collected during the projects became a constant source for further consideration and disciplinary growth. The innovations introduced – multi-disciplinarity, interdisciplinarity, preventive conservation and integral protection of heritage – foreshadowed the space for testing of ideas. However, the archaeological record of the Roman period, approached from the culture-historical point of view, dominant at the time, is still principally interpreted according to the concepts formed in 19th century and significantly reconsidered over the last couple of decades. The majority of the recovered material is not published yet, the limited access to the “finds in boxes” obliges current researchers to work on the base of available publications, and the confidence in “discoveries” induces the transfer of ideas of original researchers without further reconsideration. The abandonment of the concept of Romanization is slow, mainly due to the institutional “keepers”, as illustrated by chosen examples, e.g. the monograph Vivere Militare est. From Populus to Emperors – living on the Frontier (Golubović, Mrđić 2018) and the exhibition Roman Limes and Cities in Serbia, organized on the occasion of the 24th International Limes-Congress, as well as the new permanent display of the National Museum, opened in 2018. It may be concluded that the constant affirmation of institutional authority, where the archaeological heritage of the Roman frontier acts as an academic symbolic capital, is more important than multivocal interpretation and presentation.

Conversion of fish processing wastewater into fish feed ingredients through submerged cultivation of Aspergillus oryzae

Fish processing towards production of fillet gives rise to wastewater streams that are ultimately directed to biogas production and/or wastewater treatment. However, these wastewater streams are rich in minerals, fat, and proteins that can be converted to protein-rich feed ingredients through submerged cultivation of edible filamentous fungi. In this study, the origin of wastewater stream, initial pH, cultivation time, and extent of washing during sieving, were found to influence the amount of recovered material from the wastewater streams and its protein content, following cultivation with Aspergillus oryzae. Through cultivation of the filamentous fungus in sludge, 330 kg of material per ton of COD were recovered by sieving, corresponding to 121 kg protein per ton of COD, while through its cultivation in salt brine, 210 kg of material were recovered per ton of COD, corresponding to 128 kg protein per ton of COD. Removal ranges of 12–43%, 39–92%, and 32–66% for COD, total solids, and nitrogen, respectively, were obtained after A. oryzae growth and harvesting in the wastewater streams. Therefore, the present study shows the versatility that the integration of fungal cultivation provides to fish processing industries, and should be complemented by economic, environmental, and feeding studies, in order to reveal the most promising valorization strategy. Graphic abstract

Recovering Lithium from the Cathode Active Material in Lithium-Ion Batteries via Thermal Decomposition

In this study, calcination tests were performed on a mixed sample of lithium cobalt oxide and activated carbon at 300–1000 C under an argon atmosphere. The tests were conducted to discover an effective method for recovering lithium and cobalt from the cathode active material used in lithium-ion batteries. Additionally, the effect of soluble fluorine on the purification of lithium carbonate was investigated by the addition of lithium fluoride to an aqueous lithium hydroxide solution and a CO2 flow test was performed. The lithium recovery was ≥90% when the calcination occurred at temperatures of 500–600 C. However, the percent recovery decreased at temperatures ≥700 C. It was demonstrated that in order to increase the recovery while maintaining 99% purity of lithium carbonate in the recovered material, it was imperative to increase the temperature of the solution and to limit the F/Li ratio (mass%/mass%) in the solution to a value that did not exceed 0.05.

A Critical Review of Wastewater Resource Recovery Implementation in Indonesia

Wastewater has been recognized as a resource due to its large quantities, and it contains many valuable resources that can be converted into valuable material. Reusing or recovering resources from wastewater can reduce the environmental footprint of wastewater treatment, minimize the contamination and ensure the availability of valuable resources for the human being. The ultimate aim of wastewater resource recovery (WRR) is to create a sustainable and resilient community which is very relevant in Indonesia as this country experiences many natural or human-made disaster. To have an effective implementation, therefore, it is crucial to identify the barriers or supporting factors in its implementation of Wastewater Resource Recovery, which can be different for many regions. Through extensive literature studies, this study intends to review the possibility of WRR implementation in Indonesia. This study discusses Indonesia policy/regulation about wastewater management across all-region in Indonesia, identify barriers in WRR, compares global trends of wastewater management to Indonesia practice and list wastewater resources that potentially can be recovered in Indonesia. From the review, barriers of WRR implementation in Indonesia is most probably due to the policy and regulation of wastewater management which many of them did not support the option of WRR, instead of suggesting only safe discharge option. However, some regulations have mentioned the utilization of wastewater by-product, but it is limited only to treated water utilization. Other obstacles are social acceptance and distance between recovered material supply and demand. Social acceptance includes the human perception regarding the health risk associated with wastewater by-product. Religion also could be a potential barrier that needs to be handled in the implementation of WRR. This study could give new insight into the current state of wastewater resource recovery initiative in Indonesia; thus the strategy to overcome the barriers could be designed.