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With the rapid development of the lithium-ion battery (LIB) industry, the demand for core valuable elements in LIB has increased dramatically. A safe supply of corresponding metals is crucial to ensure the industry's sustainability. However, quantitative evaluation to reveal the supply risk including criticality of LIBs in China is still not available. In this regard, criticality analysis was carried out to identify the importance of a specific metal in the current LIBs supply chain of raw materials. Subsequently, a comprehensive methodology to evaluate supply sustainability is established in this research by considering the combined effects of material supply, economic fluctuations, and technology innovation in the time frame from 2015 to 2030. An integrated index called Chinese supply resilience is introduced, indicating that a low Chinese supply resilience has a high possibility of supply shortage of the corresponding metal while a high resilience level represents minor supply risk. The results show that insufficient material supply has already induced a severe shortage for lithium (Li) and cobalt (Co). Specifically, Chinese supply resilience of lithium moves from the threshold to the low resilience zone, whereas that for cobalt remains in the low area, both implying a high risk of supply shortage. Furthermore, three appropriate mitigation measures, that is, recycling of spent LIBs, substitution of raw materials, and an increase in domestic raw materials production are considered. Recycling demonstrates the most effective solution to alleviate the potential supply risk of corresponding materials. With this research, it may promote management efficiency on end-of-life LIBs for policy makers. Image 1 • The index of Chinese supply resilience is used to evaluate supply risk of materials. • Supply resilience for Li moves from the threshold to the low-resilience zone. • Supply resilience for Co remains in the low-resilience zone. • Effect of material supply, economy and technology innovation is analyzed. • Scenario analysis considering recycling, substitution and production is conducted. [ABSTRACT FROM AUTHOR]

Abstract The recovery of polyoxovanadate acid compounds has got increasing attention because of both sustainable necessities and material applications. In this paper, we proposed a recovery strategy of ammonium substituted polyoxovanadate acid compounds (ASPOVC) by solvent extraction from leaching/aqueous solution. It is noted that the state of the compound (solid or liquid) is possibly controllable by the type of amines (branched or linear amine chains), enlarging application fields of these compounds. Subsequently, the compounds were characterized by comprehensive techniques, from which the molecular structures with hydrogen bonds were described. The solubility parameters were calculated, and solid ASPOVC was the biggest among the four compounds, explaining formation reasons of different states. The amine extractants performed well-efficiency (more than 98.5%) for reutilization. This approach is believed to be promised for a sustainable recovery for high-value vanadium materials from waste water. Graphical abstract Image Highlights • A recovery strategy of ASPOVC was developed by solvent extraction. • The state of the compound was controllable by the type of primary amine. • The hydrogen bond extraction mechanism was verified by NMR and FTIR. • The solubility parameters were calculated, of which solid state compound was the biggest. [ABSTRACT FROM AUTHOR]

End-of-life light emitting diode (LED) associated with its electronic product is a new type of electronic waste (E-waste) and contains considerable amounts of valuable and hazardous metals. Although the quantity of a single LED is small, the total number of end-of-life LEDs is extremely significant that requires proper management and recycling from both resource and environmental points of view. Particularly, metals recycling from electronic waste has been considered as a preferred option to ensure sustainable supply of critical materials. In this research, it demonstrates a methodology to evaluate the criticality and recyclability of various types of end-of-life LEDs. Two factors, i.e. the resource index and technology index, were introduced into identifying the criticality of different types of waste LEDs, which indicates the potentials for effective metals recycling. Furthermore, combined statistical entropy and grading, the recyclability is assessed to identify the viability for metals recycling from different types of end-of-life LEDs. The results of the proposed evaluation methodology suggest that green/high luminous intensity LED exhibits significant potential for metal recycling and blue/high luminous intensity LED exhibits the lowest recycling difficulty. The aims of the research are expected to assist manufacturers and policy-makers improving the recycling effectiveness of waste LEDs especially in the metals recycling stage and developing effective waste management systems and strategies in the end-of-life stage. [ABSTRACT FROM AUTHOR]

Recovery of valuable metals from spent lithium-ion battery (LIB) is of both environmental and economic importance. Acidic leaching usually encounters issues of low selectivity or slow kinetics with considerable secondary waste generation during further purification. In this research, a closed-loop process with improved leaching selectivity for recycling of spent LiNi x Co y Mn 1-x-y O 2 battery using weak acidic leachant was demonstrated. To obtain optimal conditions of the leaching process, the effects of acid concentration, solid to liquid (S/L) ratio, temperature and reductant content were systematically investigated. Almost all Co, Li, Mn and Ni could be effectively recovered into the solution while Al remained in the residue as metallic form, after one-step leaching. The role of reductant during leaching was further evaluated which was found to be critical for the leaching kinetics. It is clear that the addition of reductant could alter the rate-controlling step of leaching from the ion diffusion in the residue layer to the surface chemical reactions. With high selectivity against impurities, this research proposed and verified a process to recover high purity Li 2 CO 3 from the cathode scrap of LIBs, and more than 90% of the global recovery rate of valuable metals can be achieved. [ABSTRACT FROM AUTHOR]

Chinese steel industry faces increasing pressure to reduce water consumption and wastewater impact. To perform the optimization of steel production process from the perspective of water use, this work describes a new superstructure-based water network optimization model using typical steel park as our study use. The water systems at different scales ( e.g. unit-scale, plant-scale and park-scale) in the water network and their interactions are modeled for optimization. To construct the optimization model: 1) All types of unit-scale typical water systems in the park are identified, and short-cut unit models are developed as the basic elements for network superstructure; 2) Intra- and inter-plant superstructures are further established to describe potential configurations of the water network at plant-scale and park-scale respectively; 3) Built up on the element models and superstructures, a Mixed Integer Non-Linear Programming model using total annual cost as objective is set up to investigate potentials for water network optimization in a steel park. To illustrate its applicability and effectiveness, an industrial case study is carried out, in which two schemes are illustrated, one scheme (termed as scheme A) considering only indirect integration between plants, the other (termed as scheme B) considering both direct and indirect integration strategy (mixed integration). In scheme A, due to the higher water efficiency and optimal configuration in the case study, the freshwater consumption and total annual cost are reduced by 22% and 21% respectively. Scheme B shows 23% savings in total annual cost, while the reduction of freshwater consumption keeps unchanged. Besides, the information about the integration strategies of all scales ( e.g. unit-, plant- and park-scale) can all be obtained, which is valuable for decision-making. [ABSTRACT FROM AUTHOR]

Proper understanding and evaluation of a metal production process is crucial for its further optimization. Economic evaluation is frequently used to estimate the practicality of a specific process based on the product life cycle assessment. However, it encounters difficulties to identify the importance of materials efficiency coupling with pollution control during evaluation on the effectiveness of process optimization. In this research, a factor defining the material recirculation is introduced to economic evaluation. Typical vanadium oxide production processes in China were evaluated by the economic evaluation model considering the whole production process, through defining a range of parameters, i.e., the materials cost, water cost, energy cost, waste treatment cost and auxiliary cost. Three V 2 O 5 production processes are analyzed and compared to each other. The production process of high purity V 2 O 5 has the best cost-effective products with high purity, the simplest production, the highest materials efficiency and the lowest cost for waste treatment. It is noticed that materials efficiency tends to be inversely proportional to waste treatment cost. Under comprehensive environmental assessment, proper pollutant control improves material recirculation percentage and reduces the expense for waste treatment which is an important aspect of economic evaluation. With this research, an optimization scheme is illustrated for the economic evaluation of typical metal production process which may provide guidance to industrial factories to optimize relevant production processes. Image 1 • A material recirculation factor is introduced to economic evaluation model. • Typical vanadium oxide production processes were evaluated. • Comprehensive environmental assessment analyzed environmental impact of the waste. • The high recirculation percentage can effectively decrease the total cost. [ABSTRACT FROM AUTHOR]

Manufacturing of chips and their associated products is a complex and multi-step process where evaluation on the materials and environmental efficiencies is difficult, and a typical life cycle assessment cannot fulfil the role. In this research, a multiple evaluation scheme in view of green manufacturing is developed by combining critical evaluation, mass flow analysis and environmental impact assessment, in order to define the green degree for chips and lamps production of light-emitting diodes (LED). Mass and energy flow are identified with a subsequent critical evaluation for the whole process to determine the importance of 160 kinds of substances, energies, waters, pollutants, and procedures. In 96 kinds of substances, the organics and metal contained substances have higher criticality and accounting for 33.49% and 56.54%, respectively. To understand the effects of critical pollutants, a comprehensive environmental assessment factor (CEA) is then implemented, and waste water in chip preparation section has larger CEA value. As a result, ten green manufacturing level is defined through a grading decision function, and LED filament lamp reaches a higher manufacturing level than surface-mounted device (SMD) based LED lamp. By defining three scenarios, the manufacturing level of largest environmental effect scenarios is 7, reflecting the CEA of the pollutants is the most critical parameter. With this evaluation system, the green manufacturing level of one manufacturing section or different manufacturing processes can be evaluated, which can guide the identification and classification of LED lamps and other products. [Display omitted] • A multiple evaluation scheme in view of green manufacturing was developed. • Critical evaluation, mass flow analysis and environmental assessment were combined. • The green manufacturing level of LED filament lamp is higher than SMD LED lamp. • Environmental impact of the pollutants largely affects the green level of LED lamp. [ABSTRACT FROM AUTHOR]