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In the recycling of end-of-life rare-earth magnets, the recovery of non-rare earth constituents is often neglected. In the present study, strong cation and anion exchange resins were tested batchwise for the recovery of the non-rare-earth constituents of permanent magnets (copper, cobalt, manganese, nickel and iron) from synthetic aqueous and ethanolic solutions. The cation exchange resin recovered most of metal ions from aqueous and ethanolic feeds, whereas the anion exchange resin could selectively recover copper and iron from ethanolic feeds. The highest uptake of iron and copper was found for 80 vol% and 95 vol% multi-element ethanolic feeds, respectively. A similar trend in selectivity of the anion resin was observed in breakthrough curve studies. Batch experiments, UV-Vis, FT-IR and XPS studies were performed to elucidate the ion exchange mechanism. The studies indicate that the formation of chloro complexes of copper and their exchange by the (hydrogen) sulfate counter ions of the resin have an important role in the selective uptake of copper from the 95 vol% ethanolic feed. Iron(II) was largely oxidized to iron(III) in ethanolic solutions and was expected to be recovered by the resin in the form of iron(II) and iron(III) complexes. The moisture content of the resin did not have a significant role on the selectivity for copper and iron., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The mineral composition and surface physico-chemical properties, i.e., specific surface area (SSA), cation exchange capacity (CEC), and surface charge of recent sediments and their submicron mineral fractions from different sedimentological environments of the Eastern Adriatic were investigated. The influence of organic matter on these properties was also investigated. It was shown that illite and mixed-layered clay minerals (MLCM) were ubiquitous and showed no size-related preferences while the occurrence of smectites, chlorites, and kaolinites varied. The smectites content increased and the chlorites decreased slightly with decreasing particle size. The sediments from the carbonate-rich environment contained no smectites or chlorites and had the highest kaolinite content. For the first time, in the recent sediments of the Adriatic Sea the poorly- and the well-crystallised kaolinite (Kl and Kl D ) were distinguished. While Kl predominates in the submicron-sized fraction, Kl D occurred only in micron-sized fractions. Authigenic aragonite of submicron-sized was determined in a distinct environment of the semi-enclosed marine lake. The differences in mineral composition and particle size of sediments and their separated fractions were reflected in a wide range of the SSA and CEC values obtained. The highest values of SSA and CEC were determined in the phyllosilicates-rich submicron-sized fractions range, 109 m 2 g -1 and 87.4 cmol + kg -1 , respectively. The submicron-sized fraction from aragonite-rich marine lake showed the lowest values of SSA (56.4 m 2 g -1 ) and CEC (38.8 cmol + kg -1 ), which are still unexpectedly high for carbonate-rich environments. The removal of organic matter resulted in a significant increase in SSA and CEC, up to 150% and 76%, respectively., Competing Interests: Declaration of competing interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

This study investigates the geochemical characteristics of recent shallow-water aragonite-rich sediments from the karstic marine lakes located in the pristine environment on the island of Mljet (Adriatic Sea). Different trace elements were used as authigenic mineral formation, palaeoredox and pollution indicators. The distribution and the historical record of trace elements deposition mostly depended on the sedimentological processes associated with the formation of aragonite, early diagenetic processes governed by the prevailing physico-chemical conditions and on the recent anthropogenic activity. This study demonstrated that Sr could be used as a proxy indicating authigenic formation of aragonite in a marine carbonate sedimentological environment. Distribution of the redox sensitive elements Mo, Tl, U and Cd was used to identify changes in redox conditions in the investigated lake system and to determine the geochemical cycle of these elements through environmental changes over the last 100 years. The significant enrichment of these elements and the presence of early formed nanostructured authigenic framboidal pyrite in laminated deeper parts of sediment in Malo Jezero, indicate sporadic events of oxygen-depleted euxinic conditions in the recent past. Concentrations of trace elements were in the range characteristic for non-contaminated marine carbonates. However, the increase in the concentrations of Zn, Cu, Pb, Sn, Bi in the upper-most sediment strata of Veliko Jezero indicates a low level of trace element pollution, resulting from anthropogenic inputs over the last 40 years. The presence of butyltin compounds (BuTs) in the surface sediment of Veliko Jezero additionally indicates the anthropogenic influence in the recent past., (Copyright © 2016 Elsevier Ltd. All rights reserved.)