The increasing importance of recycling end-of-life photovoltaic modules is demonstrated by the rising quantity of discarded crystalline silicon solar cells that contain valuable metals. Despite advanced recycling methods, the surplus of broken Si wafers poses challenges for reintegration into new module manufacturing. The present study introduces a novel recycling process that addresses this issue and promotes sustainable waste processing, focusing on the untapped resources of Si wafer breakage and environmentally harmful red mud. The proposed method uses these two critical waste materials to enable a silicothermal reduction, yielding ferrosilicon-based alloys. To comprehensively analyze the influence of the iron oxide source on alloy composition, a readily available iron oxide pigment (Bayferrox 110) is implemented as a reference material. Fe–Si-based alloys containing 15 to 65 wt % Si are produced by the silicothermal reduction with soda ash as a flux, at a temperature of 1600 °C. The use of Bayferrox as an iron oxide source facilitates the production of Fe–Si alloys that are free from additional impurities. Moreover, the use of red mud as the source of iron oxide leads to the production of Fe–Si–Ti alloys, containing up to 8.6 wt % of Ti. The inclusion of Ti in the ferrosilicon-based alloy elevates the market value of the resulting products, emphasizing the commercial viability of the suggested recycling process. By simultaneously utilizing two critical waste materials, namely, red mud and Si wafer breakage, this novel recycling strategy demonstrates significant potential, especially in view of a circular and holistic waste management.

Among the two types of lithium batteries, non-rechargeable primary-type batteries, and secondary-type rechargeable lithium-ion batteries (LIB), there have been efforts to recycle lithium only for LIB. Primary lithium batteries experience a vast market expansion with a present market volume of 2500-3200 t Li/a. Owed to a lack of apt technology, approx. 25% of this lithium is disposed of as lithium foil punching residues and is not recycled. The non-uniform lithium metal waste qualities, the high hazard potential when handling metallic lithium as well as the intake of impurities through the processing procedure are the main reasons why lithium from this source has not been recycled, yet. These problems have been solved through thermally converting lithium into Li2O and Li3N, followed by dissolution in water and precipitation with CO2, allowing for obtaining Li2CO3 already in battery-grade quality as a crude product (>99.5% purity) after precipitation. Accompanying iodine is recovered in analytical grade quality through sublimation. By means of design of experiments (DoE), a process has been developed and optimized that displays broad input material variability and consumes only water and CO2 as process chemicals. 83 +/- 2.5% isolated yield of Li2CO3 was obtained by conducting the oxidation at 400 degrees C with 0.25 g residue of whatever origin for 2.5 h. As the products bg-Li2CO3, I2, and Fe2O3 are all marketable it is almost zero waste.

The design of new composite materials using extreme biomimetics is of crucial importance for bioinspired materials science. Further progress in research and application of these new materials is impossible without understanding the mechanisms of formation, as well as structural features at the molecular and nano-level. It presents a challenge to obtain a holistic understanding of the mechanisms underlying the interaction of organic and inorganic phases under conditions of harsh chemical reactions for biopolymers. Yet, an understanding of these mechanisms can lead to the development of unusual-but functional-hybrid materials. In this work, a key way of designing centimeter-scale macroporous 3D composites, using renewable marine biopolymer spongin and a model industrial solution that simulates the highly toxic copper-containing waste generated in the production of printed circuit boards worldwide, is proposed. A new spongin-atacamite composite material is developed and its structure is confirmed using neutron diffraction, X-ray diffraction, high-resolution transmission electron microscopy/selected-area electron diffraction, X-ray photoelectron spectroscopy, near-edge X-ray absorption fine structure spectroscopy, and electron paramagnetic resonance spectroscopy. The formation mechanism for this material is also proposed. This study provides experimental evidence suggesting multifunctional applicability of the designed composite in the development of 3D constructed sensors, catalysts, and antibacterial filter systems.

Sulphuric acid is the chemical with highest production rates in the world. At present, it is mainly synthesized using vanadium pentoxide as catalyst, which determines the applied production process particularly in terms of gas pre-treatment and heat management. For processes, which cannot be run with vanadium pentoxide, alternative catalysts are required to make different SO2 qualities accessible to sulphuric acid production. Ferric oxides are a very promising alternative, since they combine higher thermal with improved chemical stability. Within this study, various ferric oxides were examined with regard to conversion rates and structural changes during application. Effects of crystal structure, particle size as well as thermal treatment and the influence of precipitation conditions were studied. Although conversion rates are very promising, it has become apparent, though, that these materials cannot compete with vanadium pentoxide in terms of conversion rate as well as long-time stability, yet. Nevertheless, from the results of this study, it is clear that high potential lies in focused catalyst optimisation.

An electrochemical-assisted leaching process using boron-doped diamond (BDD) electrodes was developed to recover valuable metals from photovoltaic modules. With BDD electrodes peroxydisulfate is generated from sulfuric acid to oxidatively dissolve copper, tin and silver from solar cell contacts. Since the oxidant is regenerated in the developed process, no additional hazardous and volatile chemicals are required, and the process can be operated solely by electricity. In addition, the dissolved metals can be electrochemically recovered at the cathode of the same cell.

Due to environmental restriction laws in oil production and processing, there is a high demand for the oil industry to reduce the use of chemical demulsifiers and to employ safer, less toxic materials. The purpose of this research is to investigate whether Alginite, a naturally occurring and abundant oil-shale rock, can be utilised as an alternative, environmentally friendly and low-cost material to demulsify various water-in-crude oil emulsions (W/O). Three W/O emulsions were prepared using saline water with respectively light, medium and heavy crude oils. The properties of the crude oils were analysed and the effectiveness of Alginite to demulsify the corresponding W/O emulsions was investigated. The results confirm that naturally occuring Alginite exhibits exceptional water-removing capacity even from emulsions containing heavy crude oil, leaving only < 1.0 wt.-% water in the remaining demulsified oil, which satisfies the required specification for industrial applications. Alginite was shown to reduce viscosity and to deform the dispersed phase in W/O emulsions even in the absence of flow. The results of this work indicate that Alginite is of significant interest in petroleum research, in industrial oil processing as well as in environmental remediation.

The production of printed circuit boards using the printing process produces considerable quantities of copper-containing etching solutions. The copper is recovered from the ammoniacal etching baths by cementation with aluminum waste at >= 99 % Cu yield rates. Instead of the usual landfilling, the aluminum-containing solution is processed into a coagulant which can be used in the treatment of mining tailings and wastewater. The aluminum oxychloride produced in this way was characterized in detail and its effectiveness as a flocculant for a finely dispersed system (kaolin suspension) was investigated and confirmed in a jar test.

Chemie Ingenieur TechnikVolume 92, Issue 3 p. 306-306 VorschauFree Access Vorschau: Chem. Ing. Tech. 4/2020 First published: 21 February 2020 https://doi.org/10.1002/cite.202070306AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume92, Issue3March 2020Pages 306-306 RelatedInformation

AbstractBei der Leiterplattenproduktion nach dem Druckverfahren fallen erhebliche Mengen kupferhaltiger Ätzlösungen an. Die Kupferrückgewinnung aus den ammoniakalischen Ätzbädern erfolgt über eine Zementation mit Aluminiumschrott mit Ausbringungsraten ≥ 99 % Cu. Anstelle der bis dato üblichen Deponierung wird die dabei anfallende aluminiumhaltige Lösung zu einem Koagulationsmittel für die Behandlung von Bergbautailings und Abwasser aufbereitet. Das hergestellte Flockungsmittel wurde eingehend charakterisiert und die Wirksamkeit als Koagulant für feindisperse Systeme im Jar‐Test untersucht und bestätigt.

In order to develop a valorization strategy for lignin, commercially available Kraft lignin was converted with sub- and supercritical water in a high-pressure vessel. The effects of reaction temperature and phase state on product formation were investigated by GC-MS analysis. The basic information of these experiments serves to develop processes for the production of aromatic-based chemicals from biomass.

In the production of aluminum oxide from the Na-aluminum silicate nepheline, despite integrated process control large quantities of residual material are produced, which must be sent to landfill. With the help of a recovery of pirssonite, it is possible to extract calcium carbonate and silica hydrogel from the nepheline sludge and, thus, considerably reduce the sludge volume. The recovered calcium carbonate can be recycled into the preparation process and the silica hydrogel can be used for the production of building materials and geopolymers.

Chemical demulsifiers are commonly applied to demulsify stable crude oil/water emulsions formed during production, extraction and transportation. The present work was carried out using a new demulsifying agent based on natural Alginite, a crude oil shale from Hungary. A model W/O emulsion, which was stable over 2 months, was prepared from 50 wt.-% crude oil (Brent type) and 50 wt.-% of brine. This emulsion was successfully split by an addition of 0.5 wt.-% Alginite within one minute. Emulsion viscosity and water content decreased and water droplet size increased rapidly after addition of Alginite verifying the demulsifying effect. After two hours, the water content of the oil was below 1 wt.-%. Alginite recycling succeeds by thermal treatment. When Alginite was calcined up to 1000 degrees C, demulsification efficiency decreased compared to the native material. Experiments with mildly thermally treated Alginite (500 degrees C), which still contains carbonates, showed that the kerogen contained in natural Alginite contributes to demulsification significantly. Chemical analysis of the separated oil showed conformity with industrial specifications.

Presently, diatomite is the dominant filter aid in the food and beverage industry due to its high porosity and satisfactory filtration resistance. However, its use is also regarded critically because of carcinogenic dust, possible trace emissions of heavy metals such as arsenic and, as an outcome of intensified environmental regulations, a future increase of disposal costs of the filtration waste. Therefore, improving cake filtration through the application of new filter aids and techniques substituting or reducing diatomite is a dynamic field of research. The present work was carried out using a new material as filter aid for beer filtration based on the natural rock alginite. Alginite is an immature oil shale from Gerce, Hungary. It consists of fossil organic and inorganic matter. To ensure compliance with the quality requirements and for the purpose of improving filtration properties of alginite, the material has to be thermally activated and washed. The obtained material A1000 is free from organic matter, shows only minor ion leaching and no swellability. In a laboratory filter system, beer was filtered with A1000 and diatomite as reference. The A1000 as filter aid leads to short filter service life because of a higher cake resistance due to beta-glucan retention. Cake resistance was successfully reduced by adding commercial filter aids, such as diatomite and perlite, respectively. The smallest cake resistance was observed upon mixing A1000 and perlite. A bright and stable beer was obtained using both A1000 and A1000 mixtures, what brings industrial filtrations with long filter service life within reach. Even more important, A1000 removes polyphenols during filtration, which is beneficial for an enhanced beer stability. From the disposal point of view, the agricultural use of filter cakes appears promising, because both alginite and perlite are well-proven soil conditioners. Hence, alginite use has the prospective of realising filtration processes in food and beverage industry with enhanced economy.

Automobile exhaust catalysts and electronic equipment, for instance, are rich in platinum group metals (PGMs). At the end of their lifecycles catalytic converters are smelted in electric arc furnaces (EAF) for PGM recovery. With approx. 40ppm, PGM depleted EAF slags still contain significantly higher amounts of PGMs than common primary sources (3–10ppm), in contrast to which the material is oxidic or elementary. Until present, there is no utilisation potential for oxidic EAF slag material. Flotation emerged as a possible option for enriching PGMs from EAF slag. Highest enrichment factor (107±9) was determined for Pt by flotation with sodium O,O′-diethyl dithiophosphate (Na-DEDTP) as collector and polypropylene glycol (PPG) as frother. The Pt content of the concentrate was approx. 1500ppm at a recovery rate up to 17±4%.

Chemie Ingenieur TechnikVolume 88, Issue 9 p. 1323-1323 Poster Modifizierte Rotschlamm-Granulate zur adsorptiven Entfernung von Schwermetallen und Phosphat aus wässrigen Systemen Dr. rer. nat. H. Schmidt, Corresponding Author Dr. rer. nat. H. Schmidt horst.schmidt@chemie.tu-freiberg.de TU Bergakademie Freiberg, Institut für Anorganische Chemie, Leipziger Straße 29, 09599 Freiberg, DeutschlandTU Bergakademie Freiberg, Institut für Anorganische Chemie, Leipziger Straße 29, 09599 Freiberg, DeutschlandSearch for more papers by this authorS. Hippmann, S. Hippmann TU Bergakademie Freiberg, Institut für Technische Chemie, Leipziger Straße 29, 09599 Freiberg, DeutschlandSearch for more papers by this authorProf. Dr. rer. nat. habil. M. Bertau, Prof. Dr. rer. nat. habil. M. Bertau TU Bergakademie Freiberg, Institut für Technische Chemie, Leipziger Straße 29, 09599 Freiberg, DeutschlandSearch for more papers by this authorProf. Dr. rer. nat. habil. W. Voigt, Prof. Dr. rer. nat. habil. W. Voigt TU Bergakademie Freiberg, Institut für Anorganische Chemie, Leipziger Straße 29, 09599 Freiberg, DeutschlandSearch for more papers by this author Dr. rer. nat. H. Schmidt, Corresponding Author Dr. rer. nat. H. Schmidt horst.schmidt@chemie.tu-freiberg.de TU Bergakademie Freiberg, Institut für Anorganische Chemie, Leipziger Straße 29, 09599 Freiberg, DeutschlandTU Bergakademie Freiberg, Institut für Anorganische Chemie, Leipziger Straße 29, 09599 Freiberg, DeutschlandSearch for more papers by this authorS. Hippmann, S. Hippmann TU Bergakademie Freiberg, Institut für Technische Chemie, Leipziger Straße 29, 09599 Freiberg, DeutschlandSearch for more papers by this authorProf. Dr. rer. nat. habil. M. Bertau, Prof. Dr. rer. nat. habil. M. Bertau TU Bergakademie Freiberg, Institut für Technische Chemie, Leipziger Straße 29, 09599 Freiberg, DeutschlandSearch for more papers by this authorProf. Dr. rer. nat. habil. W. Voigt, Prof. Dr. rer. nat. habil. W. Voigt TU Bergakademie Freiberg, Institut für Anorganische Chemie, Leipziger Straße 29, 09599 Freiberg, DeutschlandSearch for more papers by this author First published: 29 August 2016 https://doi.org/10.1002/cite.201650326Citations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume88, Issue9Special Issue: ProcessNet-Jahrestagung und 32. DECHEMA-Jahrestagung der Biotechnologen 2016September, 2016Pages 1323-1323 RelatedInformation