Resource Recovery Research Articles (Page 10)

In this study, a commercial anion-exchange resin (D301), known for high regenerability but limited selectivity, was chemically modified to enhance its sorption performance. The modification included graft polymerization of glycidyl methacrylate followed by thiourea functionalization, yielding a new sorbent, TD301, with chelating functional groups. Characterization using SEM/EDS, IR spectroscopy, XPS, and zeta potential measurements confirmed the successful introduction of sulfur- and nitrogen-containing groups, increased surface roughness, and decreased surface charge in the pH range 2–6. These changes shifted the sorption mechanism from nonspecific ion exchange to selective coordination. Sorption properties of TD301 were evaluated in mono- and bimetallic Mo–W systems, as well as in solutions obtained from real ore decomposition. The modified sorbent showed fast sorption kinetics and high selectivity for Mo(VI) at pH 1.5, while retaining high W(VI) uptake at pH 0.5. In binary systems, separation factors (α) reached 128.4, greatly exceeding those of unmodified D301. In real leachates (Mo ≈ W ≈ 0.04 g/L), TD301 selectively extracted W at pH 0.66 and Mo at pH 1.5. These findings demonstrate that TD301 is an effective sorbent for pH-dependent Mo/W separation in complex matrices, with potential for resource recovery, wastewater treatment, monitoring, and suitability for repeated use.

Copper slag (CS), a prominent industrial by-product derived from copper sulphide concentrate smelting, contains valuable copper minerals. Mineralogical analysis revealed 0.56% arsenical copper/chalcopyrite, 1.29% chalcocite, 0.25% cuprite, and 0.24% bornite as the primary copper-bearing phases. Given the rapid depletion of readily exploitable copper resources, CS has emerged as a significant source for copper production. A systematic investigation was conducted to establish optimal operational parameters for classification, grinding, and flotation. This study encompassed diverse scenarios and laboratory tests, with a particular focus on reagent application, including types and consumption rates. The findings demonstrated that Na2S is used to activate copper oxide minerals that are difficult to recover after a period of grinding, increasing the recovery rate of CS from 53.92% to 87.58%, and the two-stage grinding process is beneficial for precise control of the particle size, considering both energy efficiency and mineral recovery rate. Upon conducting a comprehensive investigation into the closed-circuit flotation process for copper recovery from CS under optimal conditions, it was determined that the copper concentrate achieved a grade of 21.24% and a recovery rate of 36.31%. Additionally, the grade of copper in the flotation tailings was diminished to 0.20%. The synchronous enrichment of copper significantly curtails total emissions in pyrometallurgical processing, mitigating pollution from CS flotation tailings. This study offers a scientific foundation for sustainable CS tailing management, promoting resource recovery and reduced environmental impact.

The landfill mining and reclamation (LFMR) project is increasingly recognized as crucial for achieving sustainable waste management and supporting global environmental goals, such as the United Nations Sustainable Development Goals related to clean energy, responsible consumption, and sustainable cities. This study evaluated the potential of combustible polymer composites (CPCs) derived from landfill mining waste for energy recovery and chemical recycling as well as resource recovery potential of soil-like fractions (SLFs). Through physico-chemical analysis and pyrolysis reaction with catalytic upgrading process, the study evaluates the suitability of CPCs for energy recovery as a solid recovered fuel (SRF) and chemical recycling feedstock. For assessing the SLFs for potential use as recycled aggregates and cover materials, total organic carbon, heavy metal concentration, and biodegradability were investigated. CPCs exhibited varied SRF and chemical feedstock qualities depending on site-specific polymer composition, while SLFs met environmental criteria for both inert waste and stabilization soil classification. The findings not only highlight technical feasibility, but also provide a transferable evaluation framework supporting ‘circular economy’ policies. Therefore, LFMR projects can contribute to sustainable waste management and energy production and provide solutions for effective material recycling, aligning with global environmental and resource conservation goals.

This study investigates the operational performance and optimization of a real greywater treatment system utilizing aluminum (Al)-based electrocoagulation (EC). The EC process was systematically evaluated and optimized through Response Surface Methodology (RSM) using the Box–Behnken Design (BBD), focusing on three critical parameters: pH, current density, and electrolysis time. Greywater samples collected from domestic sources were characterized by key physicochemical parameters including pH, COD, TSS, turbidity-ty, and electrical conductivity. The electrochemical treatment was conducted using a batch reactor equipped with Al electrodes in a monopolar configuration. Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), X-ray Diffraction (XRD), and Fourier-Transform Infrared Spectroscopy (FTIR) were employed to characterize both the electrodes and the generated sludge. Results revealed a maximum COD removal efficiency of 86.34% under optimized conditions, with current density being the most influential factor, followed by its significant interaction with pH. The developed quadratic model exhibited high predictive accuracy (R2 = 0.96) and revealed significant nonlinear and interaction effects among the parameters. Sludge characterization confirmed the presence of amorphous aluminum hydroxide and oxyhydroxide phases, indicating effective coagulant generation and pollutant capture. The treated greywater met physicochemical criteria for non-potable reuse, such as agricultural irrigation, supporting resource recovery objectives. These findings demonstrate that EC is a low-waste, chemically efficient, and scalable process for decentralized wastewater treatment, aligning with the goals of sustainable chemical engineering.

ABSTRACTGrowing environmental threats like carbon emissions, industrial wastes, and climate change introduce a paradigm shift toward circular economy (CE). The concept of CE offers a sustainable approach to waste reduction by extending the life of existing resources and promoting their re‐use. The present study aims to improve operational efficiency while minimizing its environmental impact. The key strategies include industrial symbiosis (sharing resources between industries), resource loop closure (reducing material loss), and non‐ownership models (like product‐as‐a‐service). The proposed framework was tested using agent‐based and computable general equilibrium (CGE) modeling across industrial sectors in Asia. In this regard, real‐time data amid region‐specific characteristics were integrated, while standardized metrics were applied to measure performance outcomes. Results indicated a 25% reduction in waste generation, a 30% increase in resource recovery, and a 15% drop in energy consumption. Furthermore, the operational performance was improved by 40% due to efficient use of resources. The study highlights how the proposed model can reduce environmental impact and improve the decision‐making of industrialists and policymakers by using data‐driven simulations. Moreover, the proposed framework is well aligned with SDG 12 (Responsible Consumption and Production) and SDG 13 (Climate Action), thus offering a sustainable path toward climate‐resilient and resource‐efficient industrial systems.

ABSTRACT Rapid urbanization and the expanding hospitality sector have led to a significant increase in food waste, posing complex social, environmental, and economic challenges. This study evaluates food waste generation and management practices in five restaurants in Rawalpindi, Pakistan, which produce approximately 1,000 tons of waste daily, with 60% being food waste. Findings indicate that only two establishments utilize effective waste management strategies, revealing a critical gap in sustainable practices. The research advocates for innovative techniques like waste segregation and recycling to enhance resource recovery and mitigate food waste contributions to landfills, emphasizing the need for improvements in the hospitality sector.

ABSTRACT This study presents the Pingjiang River Water Purification Project in Suzhou, a historic city facing water quality challenges due to urbanization. The project integrates advanced physical treatment techniques to restore water quality and ecological health while preserving the city's cultural heritage. The core component, the water purification plant, employs hollow-fibre ultrafiltration membrane technology to treat river water, achieving significant reductions in turbidity, suspended solids, total phosphorus, and chroma, along with improved transparency. Additionally, the plant's underground layout minimizes the land footprint, while sludge generated through the process is repurposed for brick manufacturing, supporting resource recovery. This study conducts a life cycle assessment to evaluate the environmental impacts of the plant's water purification process. Results show that electricity consumption, polyaluminium chloride, and sodium hypochlorite are the top contributors to environmental impacts, with a global warming potential of 0.207 kg CO2 eq/m3. However, the plant also offsets impacts through phosphorus removal and sludge reuse. Recommendations include optimizing chemical inputs, improving energy efficiency, and integrating renewable energy. The findings highlight the project's role in balancing water quality improvement with environmental tradeoffs and co-benefits, providing insights for sustainable urban river restoration in culturally significant contexts.

CdS-mediated electron dynamics in light-assisted anaerobic digestion: Simultaneous cadmium sequestration and methane enrichment by alkali pretreatment.

Integrating circular economy (CE) principles into battery design is critical for enhancing sustainability in energy storage, as lithium‐ion batteries grow essential for renewable energy and electric mobility. However, raw material depletion, hazardous waste, and inefficient end‐of‐life (EoL) practices threaten long‐term resource and environmental sustainability. This study reviews 94 sources, synthesizing material flow analyses, design innovations, recycling technologies, and policy frameworks to assess CE applications across the battery lifecycle. Fourthemes emerge: 1) recovery of critical materials like lithium, cobalt, and nickel via emerging recycling methods that reduce energy consumption and environmental impact; 2) design innovations such as modularity and disassembly‐oriented approaches that enable reuse and efficient resource recovery; 3) second‐life battery use in stationary renewable energy systems to extend lifespan and lower costs; and 4) regulatory mechanisms, including extended producer responsibility and digital product passports to support circular practices. Key barriers include limited recycling infrastructure, complex chemistries hindering disassembly, lack of data transparency, and fragmented regulations reducing producer accountability. Promising solutions involve low‐impact recycling, standardized modular designs, blockchain‐based material traceability, and harmonized policies enforcing EoL responsibility. The study proposes a forward‐looking framework combining technological innovation and policy reform driven by interdisciplinary collaboration to transform batteries into regenerative assets aligned with CE goals.

The extraction of uranium from seawater is crucial for sustainable nuclear energy development but is challenged by its ultralow concentration, the presence of competing ions, and the high energy demands of conventional methods. Membrane separation is a promising alternative, owing to its in simplicity, low energy consumption, and scalability. However, current membranes fail to achieve the selectivity and efficiency required for uranium capture. Herein, this study introduces a bioinspired graphene oxide-red blood cells (GO-RBC) membrane, that mimics vascular transport for ultra-selective uranium extraction. In the innovative GO-induced remodeling of red blood cell, hemoglobin (Hb) adsorbs onto the hydrophobic regions of GO and, phospholipids self-assemble into concentric hydrophilic rings around Hb. This unique "island-reef" structure within the membrane channels forces ions to follow an S-shaped path, thereby enhancing interactions with Hb. In addition, Hb catalytically reduces U(VI) to U(IV), enabling trapping of uranium while allowing competing ions to pass through. The membrane achieves an unprecedented U/V selectivity (110.6), far outperforming current technologies. Moreover, the GO-RBC membrane exhibited exceptional antifouling properties, mechanical robustness, and long-term stability. This study provides a scalable, energy-efficient solution for uranium extraction from seawater, further opening new pathways for the development of biomimetic membranes for application in resource recovery.

Acid mine drainage (AMD) remediation facilities can producetreatmentbyproducts with near ore grade concentrations of rare-earth elements(REEs), cobalt, and manganese. High concentrations of these criticalmetals in treatment solids are often associated with hydrous manganeseoxides (HMOs) through adsorption and/or coprecipitation. Chemicaland microbial oxidation processes can influence HMO formation, mineralogy,and sorption efficiency. Here, we investigate the adsorption of rare-earthelements and yttrium (REY), cobalt, and nickel over 31 days by (1)abioticHMO (δ-MnO2 and c-disordered H+ birnessite) producedby chemical oxidation and (2) bitotic HMO produced by Mn-oxidizingfungi, Paraphaeosphaeria sporulosa and Stagonospora sp. After 31 days, ∼70% of REYwas adsorbed by abiotic HMO, whereas >99% of REY was adsorbed bybioticHMO and/or fungal biomass within 7 days. Biotic HMO also adsorbed∼30% Ni and ∼75% Co; however, Co and Ni adsorption byabiotic HMO was negligible. Both biotic and abiotic HMOs were initiallypoorly crystalline. However, over the course of the experiment, abioticHMO was transformed to more crystalline phases, resulting in a reducedadsorption capacity and significant desorption of Co and Ni. In contrast,the biotic HMO remained stable and resistant to structural changesover time. This study demonstrates that biotic HMOs are highly efficientat adsorbing Co and REY and that fungal biomass can also play a significantrole in this process, particularly for REY.

Treatment Intensification of Digester Dewatering Sidestreams via Pilot- and Demonstration-Scale Revolving Algal Biofilms at Municipal Water Resource Recovery Facilities

Comparative recovery of carbon, nitrogen, and phosphorus from food waste via anaerobic digestion and Black Soldier Fly Larvae.

This study quantitatively evaluated the adsorption performance of natural bentonite for removing three dye classes-cationic (Basic dye: BEZACRYL RED GRL), anionic (Reactive dye: AVITERA LIGHT RED SE), and non-ionic (Disperse dye: BEMACRON BLUE HP3R) from synthetic textile wastewater. Batch adsorption experiments were conducted under varying conditions of contact time (15-90 min), adsorbent dosage (20-60 g L⁻1), pH (4 and 12), and temperature (25-100 °C), with dye concentrations quantified by UV-Vis spectroscopy. At a contact time of 30 min and room temperature (25 °C), maximum removal efficiencies reached 99.98% and 99.93% for cationic dye, 65.26% and 77.13% for anionic dye, and 94.04% and 79.40% for non-ionic dye at pH 4 and pH 12, respectively. For non-ionic dyes, the removal efficiency improved slightly at elevated temperature (nearly at 60 °C). Kinetic analysis showed that cationic dye adsorption followed the pseudo-second-order (PSO) model (R2 = 0.9999), indicating a chemisorption mechanism driven by electrostatic interactions with negatively charged bentonite basal planes. Non-ionic dye adsorption fitted better to the pseudo-first-order (PFO) model (R2 = 0.9821), consistent with physisorption via van der Waals forces and hydrogen bonding. Anionic dye adsorption showed poor fits to both models (R2 < 0.60), reflecting weak uptake due to electrostatic repulsion from the negatively charged bentonite surface. Equilibrium data were best described by the Langmuir isotherm, suggesting monolayer adsorption with maximum capacities of 0.486, 0.373, and 0.483 mg g⁻1 for cationic, anionic, and non-ionic dyes, respectively. Recovered dyes were reused in textile printing, producing stable and vibrant prints for cationic and non-ionic dyes, with slightly reduced intensity for anionic dyes. This work demonstrates bentonite's dual role as an efficient, low-cost adsorbent and a means for resource recovery, providing novel insights into simultaneous wastewater treatment and dye reuse across multiple dye classes.

Wastewater solids management is a key contributor to the operational cost and greenhouse gas (GHG) emissions of water resource recovery facilities (WRRFs). This study proposes a 'waste-to-energy' strategy using a hydrothermal liquefaction (HTL)-based system to displace conventional energy- and emission-intensive practices. The proposed system directs HTL-produced biocrude to oil refineries and recovers regionally tailored nitrogen and phosphorus fertilizers. In an independent facility analysis, 576 WRRFs in the contiguous U.S. (CONUS) could deploy financially viable HTL-based wastewater solids management, simultaneously achieving cost savings of 4.81M [4.04M to 5.51M] $·day-1 and a GHG reduction of 1,300 [351 to 2,140] tonne CO2 eq·day-1 while offsetting ∼ 1 to 2% of synthetic fertilizers. Key sustainability drivers include the biochemical composition of solids and internal rate of return (IRR), though IRR becomes less impactful at larger WRRFs. In a hub analysis, shared processing of wastewater solids at HTL-based treatment centers expands financially driven decarbonization opportunities to WRRF networks with solids mass flow rates higher than 5 to 7 tonne·day-1 and average transportation distances less than 80 to 155 km. Overall, this study highlights the potential of HTL-based systems for financially viable wastewater solids management while reducing GHG emissions and achieving targeted resource recovery in the CONUS.

Crystal seed-augmented microporous cathode design for enhanced phosphorus crystallization and energy-efficient recovery.

Polyvinylidene fluoride (–[CH2CF2]n–, PVDF) waste poses significant environmental challenges due to its recalcitrant nature and widespread use. This study addresses the end-of-life management of PVDF by introducing a novel, sustainable mechanochemical approach for its valorisation. We investigated the degradation of PVDF into value-added materials using ball milling with anhydrous AlCl3 to achieve a quantitative mineralisation producing AlF3 and halide-functionalised graphite, along with gaseous products (HCl and CH4). Mechanistic key steps involve Lewis-acid catalysed C–F bond activation, dehydrofluorination and aromatisation. This approach provides an effective solution for PVDF waste management while offering a promising route for the production of high-value materials from polymer waste streams. Our findings contribute to sustainable practices in polymer recycling and resource recovery, respond to pressing environmental concerns associated with fluoropolymer disposal, and demonstrate the potential to convert polymer wastes into useful products.

Nanofiltration (NF) stands as a pivotal method for lithium resource recovery. Nonetheless, traditional NF membranes predominantly rely on size exclusion and the Donnan effect, necessitating elevated operating pressures and encountering substantial hurdles in terms of ion selectivity for lithium ions. Inspired by the host-guest recognition of crown ethers toward alkali metal ions, we prepared a crown ether-functionalized loose NF membrane (CE-LNF) via interfacial polymerization of diamino-dibenzo-14-crown-4 (DAB14C4) and trimesoyl chloride on a chloromethylated polysulfone substrate. The preparation conditions of the CE-LNF membranes were systematically optimized. Results revealed that the polyamide (PA) layer structure could be precisely tuned by changing the solvent and concentration of DAB14C4. The diffusion dialysis process with low energy consumption was applied in the Mg2+/Li+ separation experiment. Interestingly, the CE-LNF membrane achieved a unique "Li+ repulsion-Mg2+ permeation" result owing to the efficient host-guest recognition of Li+ by DAB14C4 on the PA layer. During the diffusion process, the transmembrane flux of Mg2+ (0.5 mol·m-2·h-1) surpassed that of Li+ (0.01 mol·m-2·h-1) by 50-fold, leading to a significant reduction in the Mg2+/Li+ ratio in the feed (from 19.5:1 to 5.2:1) and generating a Mg2+-enriched permeate. This work proposes a novel strategy for Mg2+/Li+ separation, where CE-LNF-based continuous diffusion dialysis serves as an energy-efficient, nonpressure-driven pretreatment for high Mg2+/Li+ ratio brines. The process not only produces high-purity Mg2+ solutions but also facilitates subsequent Li+ recovery via secondary CE-LNF diffusion or conventional extraction methods.

Silicon carbide (SiC) membranes combine exceptional chemical, thermal, and mechanical stability but suffer from surface inertness that precludes functionalization. Conversely, MOFs offer unmatched molecular selectivity but are typically powders, severely limiting their practical use. To address this, we develop a generalizable route to fabricate ultrastable MOF@SiC membranes via sequential oxidation and acidification, creating abundant Si-OH sites on SiC surfaces that covalently bond with Zr-MOF crystals; the bonding mechanism between MOFs and substrates has been extensively studied. Comparing modulators, acetic acid yields higher MOF crystallinity while hydrochloric acid produces uniform, defect-rich coatings with loadings up to 89.8 g m-2. These composites endure prolonged ultrasonication and concentrated acid exposure with negligible MOF loss and exhibit wear resistance comparable to that of commercial SiC membranes. As a proof of concept for noble metal recovery, Pd(II) uptake from strongly acidic media follows rapid pseudo-second-order kinetics, achieves high adsorption capacity, and shows strong selectivity against competing ions. Thermodynamic analysis confirms a spontaneous, exothermic, and ordering adsorption process. By clarifying interfacial bonding and growth control via acid modulators, this work establishes a foundation for functionalizing inert ceramic membranes with MOFs, enabling scalable applications in separation, catalysis, and resource recovery under extreme conditions.

The Jialing River is a representative and typical canalized tributary in the upper Yangtze River basin. In the context of the 10-year fishing ban, it is imperative to elucidate the dynamics and assembly of fish communities in the Jialing River. In this study, field surveys were conducted during the flood and dry seasons from 2021 to 2025 at the Cangxi section of the Jialing River. Fifty fish species belonging to three orders and six families were collected in the study area, with Chanodichthys oxycephaloides, Hemibarbus labeo, Xenocypris davidi, and Siniperca chuatsi identified as dominant species. In addition, fish communities in this region exhibited significant temporal variations, clustering into flood season and dry season groups (p < 0.05). The result suggested that diversity indices were consistently higher in the flood season than the dry season and an increasing trend was observed during the sampling periods. Community assembly analysis revealed that the fish communities were mainly characterized by phylogenetic clustered structure, indicating environmental filtering as the deterministic process in the study area. Despite the steady recovery of fish biodiversity and resource following the fishing ban in the study area, further attention must be directed to other anthropogenic disturbances, especially habitat fragmentation. This study provides a scientific reference for fisheries management after the fishing ban in the Jialing River.