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Carbon materials are widely recognized as highly promising electrode materials for various energy storage system applications. Coal tar residues (CTR), as a type of carbon-rich solid waste with high value-added utilization, are crucially important for the development of a more sustainable world. In this study, we employed a straightforward direct carbonization method within the temperature range of 700–1000°C to convert the worthless solid waste CTR into economically valuable carbon materials as anodes for potassium-ion batteries (PIBs). The effect of carbonization temperature on the microstructure and the potassium ions storage properties of CTR-derived carbons (CTRCs) were systematically explored by structural and morphological characterization, alongside electrochemical performances assessment. Based on the co-regulation between the turbine layers, crystal structure, pore structure, functional groups, and electrical conductivity of CTR-derived carbon carbonized at 900°C (CTRC-900H), the electrode material with high reversible capacity of 265.6 mAh·g−1 at 50 mA·g−1, a desirable cycling stability with 93.8% capacity retention even after 100 cycles, and the remarkable rate performance for PIBs were obtained. Furthermore, cyclic voltammetry (CV) at different scan rates and galvanostatic intermittent titration technique (GITT) have been employed to explore the potassium ions storage mechanism and electrochemical kinetics of CTRCs. Results indicate that the electrode behavior is predominantly governed by surface-induced capacitive processes, particularly under high current densities, with the potassium storage mechanism characterized by an "adsorption–weak intercalation" mechanism. This work highlights the potential of CTR-based carbon as a promising electrode material category suitable for high-performance PIBs electrodes, while also provides valuable insights into the new avenues for the high value-added utilization of CTR. [ABSTRACT FROM AUTHOR]

Pomegranate peel is an important source of polyphenols of remarkable interest in the food, pharmaceutical and cosmetic industry. The improved extraction of total polyphenolic compounds (TPC) from pomegranate peel by solid-state fermentation (SSF) was achieved. The Box, Hunter and Hunter (BHH) followed by the central composite design (CCD) processes were performed to assess the effect of the process variables on TPC release. The statistical designs indicate that the best TPC extraction (234.85 mg GAE/gdm) by means of SSF occurs at 42 °C, 50% moisture, 5.0 pH, mineral solution (g/L): NaNO3 (3.83), KH2PO4 (1.52), MgSO4 (4.66) and KCl (1.52) at 36 h. Under the best fermentation conditions TPC (248.78 ± 1.24 mgGAE/gdm) increased 5.96-fold more than values previously reported and antioxidant activity (AA) increased 5.81-fold compared to the value obtained before the SSF optimization. High-value citric acid, α and β punicalin, α and β punicalagin, punigluconin, galloyl-HHDP hexoside and ellagic acid molecules were identified. The increased extraction of TPC by SSF provides a suitable alternative for the valorization of pomegranate peel through the recovery of molecules with high added value with potential use in the food, pharmacy and cosmetic industries; a diversification in the use of food agroindustry by-products is obtained as an approach to the circular economy model through biotechnological processes. [ABSTRACT FROM AUTHOR]

Safe, efficient, and simultaneous treatment of toxic industrial sludge and anionic contaminant crisis in one route still remains a persistent global challenge. Herein, we proposed a facile waste-control-waste conceptual design strategy to develop low-cost and high-performance sludge-based adsorbent for not only recycling of toxic waste nickel-containing sludge (NCS) but for the efficient removal of anionic contaminants in wastewater. The as-designed Ni–Al layered double oxides/calcined NCS (Ni–Al LDOs/CNCS) (216.96 m2/g, 0.44 cm3/g) with hierarchical porous structure possessed a larger specific surface area and well-developed porosity compared with raw NCS (60.52 m2/g, 0.26 cm3/g). It was proved that a higher hydrothermal temperature (180 °C) and a longer hydrothermal time (24 h) both promote the in situ assembly of LDHs nanosheets on CNCS surface. Significantly, the sludge-based adsorbent displayed high adsorption capacity towards five representative anions including F− (~ 31.1 mg/g), SO42− (~ 37.7 mg/g), NO3− (~ 21.8 mg/g), Cl− (~ 28.0 mg/g), and H2PO4− (~ 35.8 mg/g). Furthermore, the adsorbent maintained desirable adsorption capacity even after 6 adsorption/desorption cycles. Therefore, this study could be potentially extended toward design of other industrial waste sludge–derived high value-added advanced materials and for wastewater treatment applications. [ABSTRACT FROM AUTHOR]

In this paper, the high value‐added (ultra‐low degree of polymerization [ULDP]) polyvinyl alcohol (PVA) product was successfully prepared by oxidative chain scission method with sodium hypochlorite as an oxidant. When the molar ratio of PVA to NaClO is not less than 1:1.8, the reaction is stirred for several hours (≥2 h) at a temperature not exceeding 50°C. After precipitation and washing in methanol, PVA with polymerization degree of 38–150 can be obtained after drying. The infrared spectrum (IR) and nuclear magnetic hydrogen spectrum (1H‐NMR) test proved that the product obtained by this method is indeed PVA. The results of 1H‐NMR also showed that the chain broken has no selectivity and the stereoregularity of hydroxyl group did not change significantly. Through radical quenching experiment and electron paramagnetic resonance (EPR) analysis, it is proved that OCl− is the main active oxide, ·Cl makes the oxidative chain scission process can be realized quickly, and ·OH is an indispensable factor for obtaining ULDP PVA. Under the combined action of these three, high value‐added PVA with ULDP was successfully prepared. Additionally, the sodium hypochlorite oxidized the ·OH captured by 5,5‐dimethyl‐1‐pyrroline‐n‐oxide (DMPO‐OH) to 2‐hydroxy‐5,s‐dimethyl‐1‐pyrroline‐N‐oxide (HDMPO‐OH) in an alkaline environment. [ABSTRACT FROM AUTHOR]

A wide variety of biomass is available all around the world. Most of the biomass exists as a by-product from manufacturing industries. Pulp and paper mills contribute to a higher amount of these biomasses mostly discarded in the landfills creating an environmental burden. Biomasses from other sources have been used to produce different kinds and grades of biomaterials such as those used in industrial and medical applications. The present review aims to investigate the availability of biomass from pulp and paper mills and show sustainable routes for the production of high value-added biomaterials. The study reveals that using conventional and integrated biorefinery technology the ample variety and quantity of waste generated from pulp and paper mills can be converted into wealth. As per the findings of the current review, it is shown that high-performance carbon fiber and bioplastic can be manufactured from black liquor of pulping waste; the cellulosic waste from sawdust and sludge can be utilized for the synthesis of CNC and regenerated fibers such as viscose rayon and acetate; the mineral-based pulping wastes and fly ash can be used for manufacturing of different kinds of biocomposites. The different biomaterials obtained from the pulp and paper mill biomass can be used for versatile applications including conventional, high performance, and smart materials. Through customization and optimization of the conversion techniques and product manufacturing schemes, a variety of engineering materials can be obtained from pulp and paper mill wastes realizing the current global waste to wealth developmental approach. [ABSTRACT FROM AUTHOR]

The aim of the research was to assess the impact of a new structure of human capital on high value-added economic sectors in European countries. The conducted theoretical and empirical research has shown that the proposed new concept of human capital has a place to be. Three dimensions of human capital, such as quality, quantity and value, have different impacts on different sectors of European economies. Based on empirical data, the multiple linear regression model was chosen as a method that the best-fit structure of the data collected. The proposed econometric model revealed that the value of human capital is the most important component among three having very close statistical interconnections with qualitative dimensions. It was researched that Scandinavian countries scored the highest level of value dimension of human capital as well as high value-added in the economy. Open, trusted, tolerant, culturally diverse societies create preconditions for a rise for creative culture, which is a source for the formation of technological innovations and adaptation in high value-added economic sectors. Moreover, because of this value-added chain, technological innovations penetrate traditional industries as mining brings the reduction of cost, the increase in productivity and value-added, safety, and shared value in society through environmental issues. [ABSTRACT FROM AUTHOR]

Steel slag is a large amount of residual material produced in the process of steel manufacturing. With the requirements of sustainable development in China, the utilization of steel slag has become a hot issue. Through an in-depth study on steel slag, it is apparent that it has been widely used in various fields in recent years. The resource utilization of steel slag is not only conducive to resource conservation, but also conducive to sustainable production and environmental protection. In this paper, the common ways of resource utilization of steel slag in construction, agriculture, industry, and catalysis are reviewed. Steel slag as a solid waste with great development potential and large output is expected to be widely developed into high value-added products such as catalytic material in the future. [ABSTRACT FROM AUTHOR]