Aplicativo móvel de auxílio à captação de materiais recicláveis: desenvolvimento centrado no usuário / Mobile application to assist recyclable materials: user-centred development / Aplicación móvil para ayudar a materiales reciclables: desarrollo centrado en el usuario

Objetivo: Desenvolver um aplicativo móvel de auxílio à captação de materiais recicláveis. Métodos: Estudo metodológico, de desenvolvimento tecnológica centrado no usuário, realizado entre março e dezembro de 2020, a partir de cinco fases sequenciais: reconhecimento do contexto; idealização; prototipação; teste de usabilidade, complementado por um processo de validação e implementação. Participaram dessa produção tecnológica pesquisadores, desenvolvedores e integrantes de uma Associação de Materiais Recicláveis de Santa Maria, RS, Brasil. Resultados: As três fases iniciais resultaram num protótipo de aplicativo móvel. Na fase do teste de usabilidade verificouse, por meio de simulação intuitiva do protótipo, que o aplicativo é de manejo acessível, rápido e prático, podendo ser acessado por qualquer cidadão que dispõem de celular. Constatou-se, no processo de validação, que o dispositivo possui os requisitos necessários para o adequado funcionamento e interlocução entre doadores e associações receptoras de materiais recicláveis. Está disponível online após obter registro no Instituto Nacional da Propriedade Industrial. Conclusão: Revela-se que o desenvolvimento centrado no usuário é uma estratégia que amplia a difusão de conhecimento, possibilita a inclusão social e favorece o empoderamento. Como tecnologia social, o dispositivo móvel é capaz de potencializar melhores condições de trabalho e renda às associações de reciclagem. (AU)

Objective: To develop a mobile application to help the collection of recyclable materials. Methods: This is a methodological study, of user-oriented technological production, carried out between March and December 2020, from five phases: context recognition; idealization; prototyping; usability testing, complemented by a process of validation and implementation. Researchers, developers, and members of a Recyclable Materials Association in Santa Maria, RS, Brazil, participated in the collaborative production. Results: The three initial phases resulted in a prototype mobile application. In the usability test phase it was verified, through intuitive simulation of the prototype, that the application is accessible, fast and practical, and can be accessed by any citizen with a cell phone. It was verified, in the validation process, that the device has the necessary requirements for the proper functioning and dialogue between donors and associations that receive recyclable materials. It is available online after being registered with the National Institute of Industrial Property. Conclusion: It is revealed that user-centered development is a strategy that expands the dissemination of knowledge, enables social inclusion, and favors empowerment. As a social technology, the mobile device is capable of potentiating better work and income conditions for recycling associations. (AU)

Objetivo: Desarrollar una aplicación móvil para ayudar a capturar materiales reciclables. Métodos: Consiste en un estudio metodológico de producción tecnológica orientada hacia el usuario, ocurrido entre marzo y diciembre de 2020, basado en cinco fases: reconocimiento del contexto; idealización; creación de prototipos; prueba de usabilidad, complementada un proceso de validación e implementación. Participaron en la producción colaborativa investigadores, desarrolladores y miembros de una Asociación de Materiales Reciclables de Santa María, RS, Brasil. Resultados: Las tres fases iniciales resultaron en un prototipo de aplicación móvil. En la fase de prueba de usabilidad, se verificó, por medio de una simulación intuitiva del prototipo, que la aplicación es de uso accesible, rápida y práctica, y puede ser accedida por cualquier ciudadano que disponga de un teléfono celular. Se constató, en el proceso de validación, que el dispositivo cuenta con los requisitos necesarios para el correcto funcionamiento y diálogo entre donantes y asociaciones receptoras de materiales reciclables. Está disponible en línea tras obtener el registro en el Instituto Nacional de Propiedad Industrial. Conclusión: Resulta que el desarrollo centrado en el usuario es una estrategia que amplía la difusión del conocimiento, posibilita la inclusión social y favorece el empoderamiento. Como tecnología social, el dispositivo móvil es capaz de mejorar las condiciones laborales y los ingresos de las asociaciones de reciclaje. (AU)

Study on green closed-loop regeneration of waste lithium iron phosphate based on oxalic acid system.

The recovery of valuable metals from used lithium batteries is essential from an environmental and resource management standpoint. However, the most widely used acid leaching method causes significant ecological harm. Here, we proposed a method of recovering Li and Fe selectively from used lithium iron phosphate batteries by using low-concentration organic acid and completing the closed-loop regeneration. Low-concentration oxalic acid is used to carry out PO43-, which is significantly less soluble in aqueous solution than Li, two-stage selective leaching Li, where the leaching rate of Li reaches 99 %, and the leaching rate of Fe is only 2.4 %. The leach solution is then decontaminated. The solubility of Li3PO4 in aqueous solution is much smaller than that of Li2C2O4, which was required to recover Li to change the pH and Li can be recovered as Li3PO4; Fe can be retrieved as FeC2O4·2H2O, and re-prepared into lithium iron phosphate.

Aromatic amine antioxidants (AAs) and p-phenylenediamines-quinones (PPD-Qs) in e-waste recycling industry park: Occupational exposure and liver X receptors (LXRs) disruption potential.

Recently, evidence of aromatic amine antioxidants (AAs) existence in the dust of the electronic waste (e-waste) dismantling area has been exposed. However, there are limited studies investigating occupational exposure and toxicity associated with AAs and their transformation products (p-phenylenediamines-quinones, i.e., PPD-Qs). In this study, 115 dust and 42 hand wipe samples collected from an e-waste recycling industrial park in central China were analyzed for 19 AAs and 6 PPD-Qs. Notably, the median concentration of ∑6PPD-Qs (1,110 ng/g and 1,970 ng/m2) was significantly higher (p < 0.05, Mann-Whitney U test) than that of ∑6PPDs (147 ng/g and 34.0 ng/m2) in dust and hand wipes. Among the detected analytes, 4-phenylaminodiphenylamine quinone (DPPD-Q) (median: 781 ng/g) and 1,4-Bis(2-naphthylamino) benzene quinone (DNPD-Q) (median: 156 ng/g), were particularly prominent, which were first detected in the e-waste dismantling area. Occupational exposure assessments and nuclear receptor interference ability, conducted through estimated daily intake (EDI) and molecular docking analysis, respectively, indicated significant occupational exposure to PPD-Qs and suggested prioritized Liver X receptors (LXRs) disruption potential of PPDs and PPD-Qs. The study provides the first evidence of considerable levels of AAs and PPD-Qs in the e-waste-related hand wipe samples and underscores the importance of assessing occupational exposure and associated toxicity effects.

Plastics in biogenic matrices intended for reuse in agriculture and the potential contribution to soil accumulation.

The spread of biogenic matrices for agricultural purposes can lead to plastic input into soils, raising a question on possible consequences for the environment. Nonetheless, the current knowledge concerning the presence of plastics in biogenic matrices is very poor. Therefore, the objective of the present study was a quali-quantitative characterization of plastics in different matrices reused in agriculture as manures, digestate, compost and sewage sludges. Plastics were quantified and characterized using a Fourier Transform Infrared Spectroscopy coupled with an optical microscope (µFT-IR) in Attenuated Total Reflectance mode. Our study showed the presence of plastics in all the investigated samples, albeit with differences in the content among the matrices. We measured a lower presence in animal matrices (0.06-0.08 plastics/g wet weight w.w.), while 3.14-5.07 plastics/g w.w. were measured in sewage sludges. Fibres were the prevalent shape and plastic debris were mostly in the micrometric size. The most abundant polymers were polyester (PEST), polypropylene (PP) and polyethylene (PE). The worst case was observed in the compost sample, where 986 plastics/g w.w. were detected. The majority of these plastics were compostable and biodegradable, with only 8% consisting of fragments of PEST and PE. Our results highlighted the need to thoroughly evaluate the contribution of reused matrices in agriculture to the plastic accumulation in the soil system.

A Comprehensive Evaluation of Dioxins and Furans Occurrence in River Sediments from a Secondary Steel Recycling Craft Village in Northern Vietnam.

This first study investigated the presence of dioxins and furans in river sediments around a craft village in Vietnam, focusing on Secondary Steel Recycling. Sediment samples were collected from various locations along the riverbed near the Da Hoi Secondary Steel Recycling village in Bac Ninh province. The analysis was conducted using a HRGC/HRMS-DFS device, detecting a total of 17 dioxin/furan isomers in all samples, with an average total concentration of 288.86 ng/kg d.w. The concentrations of dioxin/furan congeners showed minimal variation among sediment samples, ranging from 253.9 to 344.2 ng/kg d.w. The predominant compounds in the dioxin group were OCDD, while in the furan group, they were 1,2,3,4,6,7,8-HpCDF and OCDF. The chlorine content in the molecule appeared to be closely related to the concentration of dioxins and their percentage distribution. However, the levels of furan isomers did not vary significantly. The distribution of these compounds was not dependent on the flow direction, as they were mainly found in solid waste and are not water-soluble. Although the hepta and octa congeners had high concentrations, when converted to TEQ values, the tetra and penta groups (for dioxins) and the penta and hexa groups (for furans) contributed more to toxicity. Furthermore, the source of dioxins in sediments at Da Hoi does not only originate from steel recycling production activities but also from other combustion sites. The average total toxicity was 10.92 ng TEQ/kg d.w, ranging from 4.99 to 17.88 ng TEQ/kg d.w, which did not exceed the threshold specified in QCVN 43:2017/BTNMT, the National Technical Regulation on Sediment Quality. Nonetheless, these levels are still concerning. The presence of these toxic substances not only impacts aquatic organisms in the sampled water environment but also poses potential health risks to residents living nearby.

Recycling composted human feces as biofertilizer for crop production: Assessment of soil and lettuce plant tissue contamination by Escherichia coli and human adenovirus.

Using waste from sewage systems, particularly human excreta, could save resources and increase soil fertility, contributing to nutrient management. However, because of the pathogenic content in human feces, this resource can pose health risks to farmers and consumers. Therefore, this work analyzed the behavior of the microorganisms: Escherichia coli ATCC13706 and human adenovirus (HAdV-2) in the soil and the internal part of the plant tissue during the vegetative stage after applying spiked composted human feces as biofertilizer. In a greenhouse, we simulated the application of the biofertilizer in lettuce cultivation by spiking three concentrations of E. coli (6.58, 7.31, and 8.01 log10 CFU.g-1) and HAdV-2 (3.81, 3.97, and 5.92 log10 PFU.g-1). As a result, we achieved faster decay in soil at higher concentrations of E. coli. We estimated linear decay rates of -0.07279, -0.09092, and -0.115 days, corresponding to T90s of 13.7, 11.0, and 8.6 days from higher to smaller concentrations of E. coli, respectively. The estimated periods for the inactivation of 4 logarithmic units of E. coli bacteria in soil are longer than the cultivation period of lettuce for all concentrations studied. Concerning the bacterial contamination in plants, we found E. coli in the internal part of the leaves at the highest concentration tested during the first three weeks of the experiment. Furthermore, HAdV-2 was found in roots at a stable concentration of 2-2.3 log10 PFU.g-1 in five of the six samples analyzed. Therefore, bacterial infection could pose a risk, even if fresh greens are washed before consumption, especially for short-term cultures. Regarding viral infection, a positive result in the roots after disinfection may pose a risk to root and tubercule vegetables. These discoveries highlight the importance of conducting comprehensive evaluations of hygiene practices in incorporating organic amendments in crops, explicitly aiming to minimize the risk of post-contamination.

Plastic waste management in recycling facilities: Intentionally generated MPs as an emerging contaminant.

There is little knowledge about microplastic (MP) pollution in plastic recycling facility (PRF) wastewater. In this study, MPs in the wastewaters of four PRFs located in Türkiye were characterized for size, shape, color, and polymer types after sieving from 5,000 µm to the lowest 75 µm with seven sieves. The wet peroxide oxidation procedure was applied before attenuated total reflectance fourier transform infrared spectroscopy analysis for polymer identification. Polyethylene, and polypropylene were the dominant (75 % of total count) MP types within 22 polymer types. Average hit qualities of polymers increased from 69 % to above 84 % for the device software (OPUS) and open software (OpenSpecy). The abundance of MPs was determined as 53,987 MPs/L and 0.8 g MP/L for mixed PRFs 7,582 MPs/L and 4.6 g/L for the LDPE recycling facility, and 2,196 MPs/L and 0.06 g MPs/L for the granulation cooling water by count and weight, respectively. Small-sized MPs are found in the bottom sample much more than the surface and effluent samples in the washing tank. This indicated that MPs adsorbed the pollutants settled in the washing tank due to adsorbed pollution/biofilm. A maximum of 4.6 kg MP/ton of plastic recycled can be discharged as MPs that can be recovered. Considering the plastics recycling capacity, discharged MPs in these PRFs are possibly above 30,000 tons.

Bubble Turbulent Gas-Permeable Membrane for Ammonia Recovery from Swine Wastewater: Mass Transfer Enhancement and Antifouling Mechanisms.

Recovering ammonium from swine wastewater employing a gas-permeable membrane (GM) has potential but suffers from the limitations of unattractive mass transfer and poor-tolerance antifouling properties. Turbulence is an effective approach to enhancing the release of volatile ammonia from wastewater while relying on interfacial disturbance to interfere with contaminant adhesion. Herein, we design an innovative gas-permeable membrane coupled with bubble turbulence (BT-GM) that enhances mass transfer while mitigating membrane fouling. Bubbles act as turbulence carriers to accelerate the release and migration of ammonia from the liquid phase, increasing the ammonia concentration gradient at the membrane-liquid interface. In comparison, the ammonium mass transfer rate of the BT-GM process applied to real swine wastewater is 38% higher than that of conventional GM (12 h). Through a computational fluid dynamics simulation, the turbulence kinetic energy of BT-GM system is 3 orders of magnitude higher than that of GM, and the effective mass transfer area is nearly 3 times that of GM. Seven batches of tests confirmed that the BT-GM system exhibits remarkable antifouling ability, broadens its adaptability to complex water quality, and practically promotes the development of sustainable resource recycling.

Correlation analysis and predicting modeling of pyrolysis gas based on landfill excavated waste pyrolysis characteristics.

The contribution of excavated waste to waste management is multifaceted, including minimization, non-hazardous disposal, access to useable land resources, improved waste management techniques and public environmental awareness, consistent with recent circular economy initiatives. Pyrolysis can be converted into tar, pyrolysis gas and char with recyclable utilization, enriching the application of pyrolysis technology in the field of excavation waste. In this study, the pyrolysis system includes horizontal tube furnace, gas collection device and Micro GC. The excavated waste was pyrolyzed at a temperature of 500∼900 °C with a heating rate of 10 °C/min. Pyrolysis gases include H2, CO, CO2, CH4, C2H4, C2H6 and C3H8. Pyrolysis was divided into four stages, the main decomposition range is 230∼500 °C, with a weight loss rate of 68.49% and a co-pyrolysis behavior. As the temperature increases, the tar and char decreased and the gas production increased significantly, and the pyrolysis gas reached 47.02% at 900 °C. According to Pearson correlation coefficient analysis, the generation of H2 and CO is positively correlated with temperature. Therefore, the target products can be influenced by changing the parameters, when considering the practical utilization of the excavated waste pyrolysis products. On this basis, the prediction models were built by polynomial fitting method. This model can reduce the experimental exploration cycle, reduce the cost, and accurately predict the pyrolysis gas, which has practical guidance for the application of pyrolysis industry, and provides a theoretical basis for the resource recycling and energy recovery of landfill.

Reduction of the environmental and health consequences of cigarette butt recycling by removal of toxic and carcinogenic compounds from its leachate.

Cigarette butt is a hazardous waste, and its management faces many challenges. The generation of leachate containing many pollutants including heavy metals is one of the limitations of recycling cigarette butts. The aim of this study was to reduce organic compounds and heavy metals in leachate resulting from cigarette butt recycling in an electrocoagulation reactor. For this purpose, two samples, including freshly smoked cigarette butts and littered cigarette butts, were processed and the treatment of leachate resulting from them was studied in an electrocoagulation reactor. The efficiency of leachate treatment was investigated in the treatment time of 10-40 min and current intensity of 20-100 mA. The results showed that the minimum reduction of chemical oxygen demand and turbidity was 25.3% and 33.4%, respectively. Increasing the current intensity and treatment time increased the efficiency of removing turbidity and chemical oxygen demand up to 47.1% and 41.2%, respectively, in optimum conditions. The reduction of nickel, chromium, cadmium, and lead in the lowest current density and minimum treatment time was more than 90%, which increased to more than 99% with the increase of the current density and treatment time. The use of electrocoagulation is a suitable solution to reduce heavy metals in leachate resulting from cigarette butt recycling, while the proper reduction of organic compounds in this type of leachate requires further treatment processes.

Recycling thermally deactivated asbestos cement in mortar: A possible route towards a rapid conclusion of the "asbestos problem".

The "asbestos problem" arises from the fact that asbestos is still abundant in many buildings and represents a hazard for human health. Current strategies adopted by law aiming at mitigating this hazard are far from being ideal. A smarter solution would be an energy sustainable detoxification treatment followed by recycling. If adopted, it would preserve the environment from pollution, natural resources from depletion and human health from hazard. Asbestos-cement slates were thermally deactivated through a sustainable process and reused in mortar for plaster applications. We found that the addition up to 7 wt% of the deactivated product does not affect significantly the water demand; does not affect thixotropy, stickiness and spreadability of the plastic mixture; slightly increases the strength of the mortar; does not compromise mechanical properties after aging. Considering the huge amount of traditional mortar employed worldwide, a rapid end of the "asbestos problem" is envisaged.

Consumer behavior in the model of the circular economy in the field of handling discarded items.

The circular economy is a way of eliminating the shortage of raw materials that Europe is currently facing. However, it is necessary to explicitly identify the problems that prevent greater involvement in the CE. This article is focused on consumers and how they treat discarded or non-functional items. The aim was to fill the research gap, i.e. to compile a suitable CE model and define a methodology that would ensure the efficient disposal of non-functional or unsuitable items by consumers. An original methodology was drawn up to conduct the representative research, designed to lead to the practical application of the proposed CE model. The research explored how consumers treat non-functional or unsuitable items, the costs they incur in discarding, renovating, reusing, and recycling such items, and the alternative costs of unsorted municipal waste. After the data had been implemented into the model the circular economy was proven to have an economic benefit for the national economy in all groups. However, the economic disadvantage for consumers was also calculated, where the cost of involvement in the CE is higher than the cost of unsorted municipal waste. This means that people are motivated to play a part in the CE more by their own responsible approach to life, or social pressure from those around them. Based on this research it may be said that economic aspects are one reason that consumers tend to be reluctant to get more involved in the CE. Unless there is a significant rise in the cost of municipal waste that would motivate consumers to move towards the CE for financial reasons, in order to support the CE consumers need to be better stimulated, educated and informed as much as possible through the media.

Process and systematic study of gold recovery from flexible printed circuit boards (FPCBs) using a choline chloride-ethylene glycol system.

The traditional hydrometallurgy technology has been widely used to recover precious metals from electronic waste. However, such aqueous recycling systems often employ toxic/harsh chemicals, which may cause serious environmental problems. Herein, an efficient and environment-friendly method using a deep eutectic solvent (DES) mixed system of choline chloride-ethylene glycol-CuCl2·2H2O is developed for gold (Au) recovery from flexible printed circuit boards (FPCBs). The Au leaching and precipitation efficiency can reach approximately 100 % and 95.3 %, respectively, under optimized conditions. Kinetic results show that the Au leaching process follows a nucleation model, which is controlled by chemical surface reactions with an apparent activation energy of 80.29 kJ/mol. The present recycling system has a much higher selectivity for Au than for other base metals; the two-step recovery rate of Au can reach over 95 %, whereas those of copper and nickel are < 2 %. Hydrogen nuclear magnetic resonance spectroscopy (HNMR) and density functional theory (DFT) analyses confirm the formation of intermolecular hydrogen bonds in the DES mixed system, which increase the system melting and boiling points and facilitate the Au leaching process. The Au leaching system can be reused for several times, with the leaching efficiency remaining > 97 % after five cycles. Moreover, ethylene glycol (EG) and choline chloride (ChCl) act as aprotic solvents as well as coordinate with metals, decreasing the redox potential to shift the equilibrium to the leaching side. Overall, this research provides a theoretical and a practical basis for the recovery of metals from FPCBs.

Recovery of aluminum oxide and iron oxide from aluminum electrolysis iron-rich cover material and preparation of aluminum fluoride.

In aluminum electrolysis, the iron-rich cover material is formed on the cover material and the steel rod connecting the carbon anode. Due to the high iron content in the iron-rich cover material, it differs from traditional cover material and thus requires harmless recycling and treatment. A process was proposed and used in this study to recovery F, Al, and Fe elements from the iron-rich cover material. This process involved aluminum sulfate solution leaching for fluorine recovery and alkali-acid synergistic leaching for α-Al2O3 and Fe2O3 recovery were obtained. The optimal leaching rates for F, Na, Ca, Fe, and Si were 93.92, 96.25, 94.53, 4.48, and 28.87%, respectively. The leaching solution and leaching residue were obtained. The leaching solution was neutralized to obtain the aluminum hydroxide fluoride hydrate (AHFH, AlF1.5(OH)1.5·(H2O)0.375). AHFH was calcined to form a mixture of AlF3 and Al2O3 with a purity of 96.14%. The overall recovery rate of F in the entire process was 92.36%. Additionally, the leaching residue was sequentially leached with alkali and acid to obtain the acid leach residue α-Al2O3. The pH of the acid-leached solution was adjusted to produce a black-brown precipitate, which was converted to Fe2O3 under a high-temperature calcination, and the recovery rate of Fe in the whole process was 94.54%. Therefore, this study provides a new method for recovering F, Al, and Fe in iron-rich cover material, enabling the utilization of aluminum hazardous waste sources.

Analysis of Poly(ethylene terephthalate) degradation kinetics of evolved IsPETase variants using a surface crowding model.

Poly(ethylene terephthalate) (PET) is a major plastic polymer utilized in the single-use and textile industries. The discovery of PET-degrading enzymes (PETases) has led to an increased interest in the biological recycling of PET in addition to mechanical recycling. IsPETase from Ideonella sakaiensis is a candidate catalyst, but little is understood about its structure-function relationships with regards to PET degradation. To understand the effects of mutations on IsPETase productivity, we develop a directed evolution assay to identify mutations beneficial to PET film degradation at 30 °C. IsPETase also displays enzyme concentration-dependent inhibition effects, and surface crowding has been proposed as a causal phenomenon. Based on total internal reflectance fluorescence microscopy and adsorption experiments, IsPETase is likely experiencing crowded conditions on PET films. Molecular dynamics simulations of IsPETase variants reveal a decrease in active site flexibility in free enzymes and reduced probability of productive active site formation in substrate-bound enzymes under crowding. Hence, we develop a surface crowding model to analyze the biochemical effects of three hit mutations (T116P, S238N, S290P) that enhanced ambient temperature activity and/or thermostability. We find that T116P decreases susceptibility to crowding, resulting in higher PET degradation product accumulation despite no change in intrinsic catalytic rate. In conclusion, we show that a macromolecular crowding-based biochemical model can be used to analyze the effects of mutations on properties of PETases and that crowding behavior is a major property to be targeted for enzyme engineering for improved PET degradation.

Blood lead, cadmium and hair mercury concentrations and association with soil, dust and occupational factors in e-waste recycling workers in Bangladesh.

BACKGROUND: Electronic waste (e-waste) recycling activities release toxic metals, which pose substantial hazard to the environment and human health. We evaluated metal concentrations in biological and environmental samples, and examined the associations between biological lead (Pb), cadmium (Cd), and mercury (Hg) with soil and dust metals, and other possible determinants, among populations exposed and non-exposed to e-waste in Bangladesh. METHODS: A total of 199 e-waste workers and 104 non-exposed individuals were recruited. We measured blood Pb (BPb) and Cd (BCd) concentrations and total Hg (THg) from hair samples. Data were collected on occupational, and behavioral factors. We fitted an elastic net regression (ENET) to model the relationship between a set of influencing factors and metals as outcome variables while controlling for potential covariates. RESULTS: The median concentrations of BPb (11.89 µg/dL) and BCd (1.04 µg/L) among exposed workers were higher than those of non-exposed workers (BPb: 3.63 µg/dL and BCd: 0.83 µg/L respectively). A 100 ppm increment in soil Pb level was associated with an increase in ln-Pb (transformed) in blood (ß = 0.002; 95% CI = 0.00, 0.02). Similarly, ln-BCd level increased (ß = 0.02; 95% CI = 0.001, 0.07) with every ppm increase in dust Cd level. The number of years worked in e-waste activities was associated with elevated ln-BPb (ß = 0.01; 95% CI = 0.01, 0.02) and ln-BCd levels (ß = 0.003; 95% CI = 0.00, 0.05). Smoking significantly contributed to elevated levels of ln-BCd (ß = 0.46; 95% CI = 0.43, 0.73). An increment of 100 kg of e-waste handling per week led to an increase in ln-BPb levels (ß = 0.002; 95% CI = 0.00, 0.01), while respondents knowledge about adverse impact on e-waste reduced the ln-BPb level (ß = -0.14; 95% CI = -0.31, -0.03). Fish consumption frequency had a positive association with THg in hair. CONCLUSIONS: Our data show the need for workplace controls to reduce exposure to Pb and Cd with a broader view of exposure source taken.

Comprehensive Technology for Recycling and Regenerating Materials from Spent Lithium Iron Phosphate Battery.

The lithium iron phosphate (LFP) battery has been widely used in electric vehicles and energy storage for its good cyclicity, high level of safety, and low cost. The massive application of LFP battery generates a large number of spent batteries. Recycling and regenerating materials from spent LFP batteries has been of great concern because it can significantly recover valuable metals and protect the environment. This paper aims to critically assess the latest technical information available on the echelon utilization and recycling of spent LFP batteries. First, it focuses on the progress of disassembly, evaluation and detection, regrouping, and application in echelon utilization. Then, the recycling technologies, including pretreatment, direct repair, and material regeneration, of spent LFPs are summarized. Finally, the paper proposes some challenges in the echelon utilization and recycling of spent LFP batteries, and concludes with recommendations for an intelligent, refined, and clean LFP battery circulation system that are required to ensure the sustainable development of spent LFP battery recycling.

Coupling redox flow desalination with lithium recovery from spent lithium-ion batteries.

Electrochemical redox flow desalination is an emerging method to obtain freshwater; however, the costly requirement for continuously supplying and regenerating redox species limits their practical applications. Recycling of spent lithium-ion batteries is a growing challenge for their sustainable utilization. Existing battery recycling methods often involve massive secondary pollution. Here, we demonstrate a redox flow system to couple redox flow desalination with lithium recovery from spent lithium-ion batteries. The spontaneous reaction between a battery cathode material (LiFePO4) and ferricyanide enables the continuous regeneration of the redox species required for desalination. Several critical operating parameters are optimized, including current density, the concentrations of redox species, salt concentrations of brine, and the amounts of added LiFePO4. With the addition of 0.5920 g of spent LiFePO4 in five consecutive batches, the system can operate over 24 h, achieving 70.46 % lithium recovery in the form of LiCl aqueous solution at the concentration of 6.716 g·L-1. Simultaneously, the brine (25 mL, 10000 ppm NaCl) was desalinated to freshwater. Detailed cost analysis shows that this redox flow system could generate a revenue of ¥ 13.66 per kg of processed spent lithium-ion batteries with low energy consumption (0.77 MJ kg-1) and few greenhouse gas emissions indicating excellent economic and environmental benefits over existing lithium-ion battery recycling technologies, such as pyrometallurgical and hydrometallurgical methods. This work opens a new approach to holistically addressing water and energy challenges to achieve sustainable development.

Valorization of non-edible fruit seeds into valuable products: A sustainable approach towards circular bioeconomy.

Global imperatives have recently shown a paradigm shift in the prevailing resource utilization model from a linear approach to a circular bioeconomy. The primary goal of the circular bioeconomy model is to minimize waste by effective re-usage of organic waste and efficient nutrient recycling. In essence, circular bioeconomy integrates the fundamental concept of circular economy, which strives to offer sustainable goods and services by leveraging biological resources and processes. Notably, the circular bioeconomy differs from conventional waste recycling by prioritizing the safeguarding and restoration of production ecosystems, focusing on harnessing renewable biological resources and their associated waste streams to produce value-added products like food, animal feed, and bioenergy. Amidst these sustainability efforts, fruit seeds are getting considerable attention, which were previously overlooked and commonly discarded but were known to comprise diverse chemicals with significant industrial applications, not limited to cosmetics and pharmaceutical industries. While, polyphenols in these seeds offer extensive health benefits, the inadequate conversion of fruit waste into valuable products poses substantial environmental challenges and resource wastage. This review aims to comprehend the known information about the application of non-edible fruit seeds for synthesising metallic nanoparticles, carbon dots, biochar, biosorbent, and biodiesel. Further, this review sheds light on the potential use of these seeds as functional foods and feed ingredients; it also comprehends the safety aspects associated with their utilization. Overall, this review aims to provide a roadmap for harnessing the potential of non-edible fruit seeds by adhering to the principles of a sustainable circular bioeconomy.

Thermal utilization techniques and strategies for secondary aluminum dross: A review.

Secondary aluminum ash (SAD) disposal is challenging, particularly in developing countries, and presents severe eco-environmental risks. This paper presents the treatment techniques, mechanisms, and effects of SAD at the current technical-economic level based on aluminum ash's resource utilization and environmental properties. Five recovery techniques were summarized based on aluminum's recoverability in SAD. Four traditional utilization methods were outlined as per the utilization of alumina in SAD. Three new utilization methods of SAD were summarized based on the removability (or convertibility) of aluminum nitride in SAD. The R-U-R (recoverability, utilizability, and removability) theory of SAD was formed based on several studies that helped identify the fingerprint of SAD. Furthermore, the utilization strategies of SAD, which supported the recycling of aluminum ash, were proposed. To form a perfect fingerprint database and develop various relevant techniques, future research must focus on an extensive examination of the characteristics of aluminum ash. This research will be advantageous for addressing the resource and environmental challenges of aluminum ash.