Resource Recovery Research Articles

Recently, landfill mining (LFM) has emerged as a promising strategy for addressing the challenges of waste management, resource recovery, and climate change mitigation. This work explores the potential of landfill mining to transform traditional landfills from environmental liabilities into assets. By recovering nutrients, energy, and materials from landfill leachate, landfill mining can reduce greenhouse gas (GHG) emissions, particularly methane (CH 4 ), while contributing to the circular economy. This study evaluates the technologies applied in landfill mining, such as bioreactors, anaerobic digestion, and leachate recirculation, based on published literature from 2000 to 2025, focusing on their value in resource recovery. More specifically, this study aims at recovering renewable CH 4 energy from leachate and extracting macro-nutrients such as nitrogen (N), phosphorus (P), and potassium (K) which can be turned into commercial fertilizers. This study further analyzes the advantages of landfill mining, which include reducing CH 4 emissions by up to 30% and the potential energy value of 15 GWh from 1.5 million m 3 of CH 4 . The study also explores the socio-economic consequences of landfill mining, focusing on employment opportunities, improved waste management systems, and enhanced local community welfare. Additionally, this work discusses the technological, financial, and regulatory challenges that hinder the widespread adoption of landfill mining for promoting circular economy. Finally, this work calls for further investment, research, and policy development to unlock the full potential of landfill mining as a sustainable waste management strategy and a key contributor to resource recovery in the circular economy paradigm.

In recent years, public discourse on pesticide impacts has increasingly recognized institutional and structural racism as key drivers of health disparities in Black, Indigenous, and People of Color (BIPOC) communities. While pesticides are vital for crop protection from causing yield losses, extensive research highlights their adverse effects on environmental quality and human health. These impacts disproportionately burden BIPOC populations, making pesticides a major environmental justice (EJ) concern like many other environmental pollutants. Despite progress in understanding these effects and advancing EJ, significant technical, social, and policy gaps remain. The objective of this review is to systematically examine critical gaps in technical, social, and policy dimensions, as well as the environmental and human health impacts of pesticide exposure on BIPOC communities in the United States, through the lens of environmental justice. This review synthesizes 128 sources peer-reviewed articles, books, reports on pesticides, EJ, and BIPOC communities in the U.S. Key findings reveal uneven distribution of pesticide-related health and environmental burdens along racial, ethnic, and socioeconomic lines. Non-Hispanic Blacks and Mexican Americans exhibit higher pesticide biomarkers and greater exposure risks than non-Hispanic Whites. Structural racism and classism, rooted in historical systems, perpetuate these inequities, compounded by regulatory failures and power imbalances. In addition, the EPA has flagged 31 pesticide manufacturing facilities for “Significant Violations” of key environmental laws, including the Clean Air Act, Clean Water Act, and Resource Conservation and Recovery Act. These systemic issues underscore urgent needs for transparency, accountability, and equitable policy reform. An EJ framework exposes critical knowledge gaps and calls for structural changes to ensure equal protection and responsive policies for the most affected communities.

As global efforts towards green development intensify, eco-friendly materials have become pivotal to achieving sustainability. Wood, a natural, renewable, and environmentally benign biomass, holds great promise for green material applications due to its abundance and ecological benefits. Recent advances in functional modification techniques—such as oxidation, grafting, and nanoparticle incorporation—have significantly enhanced wood’s physical and chemical properties while introducing new environmental functions. These developments have expanded its applications in pollution control, resource recovery, and environmental restoration. In particular, modified wood exhibits outstanding adsorption capacity for heavy metal ions (Pb2+, Cd2+, Cu2+), offering an efficient and sustainable approach to water pollution remediation. This paper reviews the fundamental structure and properties of wood, summarizes recent progress in the development of functionalized wood for heavy metal ion adsorption, and analyzes the influence of various modification methods on adsorption performance. Finally, it outlines future directions for optimizing wood functionalization technologies, providing theoretical foundations and practical guidance for advancing their applications in wastewater treatment and heavy metal pollution control.

In recent years, industrial symbiosis (IS) has gained attention as a strategy to enhance circularity and to reduce the environmental impacts of solid waste management through resource reuse and recovery. Life Cycle Assessment (LCA) is increasingly used to evaluate the environmental performance of such inter-industry collaborations. Given the growing diversity of IS practices and LCA models, this updated review serves as a methodological reference, mapping existing approaches and identifying gaps to guide future research on the systematic assessment of circular strategies. Moreover, it investigates the environmental performance of IS approaches in the field, based on the LCA results of the analyzed case studies. We analyzed 48 peer-reviewed studies to examine how LCA has been applied to model and assess the environmental impacts and benefits of IS in the context of waste management. The literature revealed wide methodological variability, including differences in system boundaries, functional units, and impact categories, affecting comparability and consistency. Case studies confirm that IS can contribute to reducing environmental burdens, particularly with regard to climate change and resource depletion, though challenges remain in modelling the complex inter-organizational exchanges and accessing reliable data. Socio-economic aspects are increasingly considered but remain underrepresented. Future research should focus on methodological improvements, such as greater standardization and the better integration of indirect effects, to strengthen LCA in decision-making and to explore a wider range of scenarios reflecting different stakeholders, analytical perspectives, and the evolution of symbiotic systems over time.

Polyurethane (PU) foams are widely applied in cushioning, packaging, and construction, but their reliance on petroleum-based feedstocks and limited durability raises sustainability concerns. This study investigates the incorporation of ground tyre rubber (GTR) into flexible PU foams to enhance performance while promoting circular economy goals. Foams were synthesized via the free-rise method using polyethylene glycol (PEG 400) and isophorone diisocyanate (IPDI), with GTR fillers (≤0.4 mm) and silicone oil surfactant. Fourier-transform infrared spectroscopy confirmed successful urethane network formation, while scanning electron microscopy revealed that GTR disrupted cellular morphology, increasing porosity and heterogeneity. Mechanical analysis showed a substantial decline in compressive strength and modulus with increasing filler loading, attributed to poor filler matrix compatibility and uneven dispersion. Thermal analysis highlighted a dual effect where GTR suppressed the glass transition temperature, reflecting reduced microphase separation, yet improved thermal stability by delaying degradation onset and increasing residual char yield. Silicone oil partially mitigated structural collapse by refining cell morphology and enhancing compressive behavior. The results showed a trade-off between sustainability-driven waste rubber utilization and foam integrity. While GTR incorporation advances responsible resource recovery and contributes to Sustainable Development Goals (SDGs), unmodified fillers compromise mechanical reliability, limiting high-performance applications. Future work should emphasize interfacial engineering, including surface modification and compatibilizer integration, to reconcile environmental imperatives with performance requirements.

ABSTRACT The primary objective of this study was to develop an interpretable machine learning framework for accurate prediction of weight on bit (WOB) in horizontal wells. With the advancement of oil and gas technologies, horizontal drilling has become a key method for resource recovery, but drag in ultra-long sections reduces efficiency. Traditional WOB calculation methods rely on mathematical models and physical experiments, which are costly and complex. To address this, eight parameters, including well depth and hook load, were selected as model inputs. An ensemble tree model optimized by Bayesian algorithms was built to capture parameter – WOB relationships. SHapley Additive exPlanations (SHAP) were applied to interpret model outputs and assess parameter importance. Performance was evaluated using R2, MSE, MAE, and RMSE. The best-performing ensemble model was further integrated into a CNN-LSTM to enhance temporal feature learning. This hybrid approach achieved an R2 of 0.96, representing about a 10% improvement over standalone models. The proposed framework thus offers a reliable and interpretable tool for WOB prediction, providing valuable reference for improving drilling efficiency in horizontal well sections.

The current transition to the circular economy of construction is imperatively concerned with diminishing resource depletion, construction waste mitigation, and sustainability. The concept of modularity involves prefabrication of the building elements , accomplishing great efficiency and reduced environmental impact and therefore, creates a perfect ground for transitioning the ideals of the circular economy. The existing research suggested that modular buildings can take advantage of Design for Disassembly (DfD) principles in achieving up to 50% better rates of resource recovery compared to traditional construction methods, including embodied carbon and resource consumption. In addition, the use of material passports and blockchain - enabled tracking systems contributes to greater traceability of building components, ensuring that elements of a building are used at the end of their lifecycle. Through BIM, such designs can be optimized for circularity by enabling precise material quantification and adaptive reuse planning. There are still significant constraints holding up the realization of these benefits, including regulatory constraints, non - standardized modular component options, and financial disincentives relating to material reuse. This study therefore advocates policy intervention, financial incentives, and collaborative frameworks to address these barriers. The research moves forward by discussing some of the issues facing the construction industry and even embracing cutting - edge technological novelties by thinking about moving the industry closer to its transformative journey away from the linear "take - make - dispose" concept and into regenerative politics through circular action by highlighting all the benefits of circular, modular construction. The potential of sustainable architecture would be greatly transformed and promoted with how modular construction is applied, particularly to match circular economy principles which are aiming for a new level of resource efficiency.

In the context of the new energy vehicle industry's rapid growth, the large-scale abandoned of used power batteries has become a pressing issue that requires immediate attention. This paper developed a four-level used power battery reverse logistics network optimization model using bibliometric analysis, mixed research methods and system dynamics simulation. It focuses total cost minimization by integrating mixed-integer linear programming and variable neighborhood-genetic algorithm (VNS-GA). Taking the Northeast region of China as a case, this paper explores the spatiotemporal distribution feature of retired batteries and verifies its model effectiveness in cost control, transport optimization and resource recovery efficiency enhancement. The findings of the research shown that the model could effectively reduce total operation cost, improve capacity layer filling and regeneration processing efficiency, optimize operating routes and node distribution, reduce environmental risk in practice. This paper offered a theoretical foundation and practical guidance for the scientific planning and construction of regional used power battery recycling systems, as well as decision support for promoting the green and sustainable development of new energy vehicle industry in order to achieve national dual carbon strategic goals.

CoFe2O4 loaded onto red brick powder (CoFe2O4@RBP) was synthesized via coprecipitation followed by post-calcination and employed as a heterogeneous catalyst to activate peroxymonosulfate (PMS) for the degradation of methylene blue (MB), thereby valorizing red brick demolition waste within a circular economy pathway and aligning the study with sustainability-oriented resource recovery. The effects of pH, PMS concentration, catalyst dosage, and coexisting substances on MB removal were systematically investigated. Complete MB removal was achieved within 30 min, and the apparent rate constant for the CoFe2O4@RBP/PMS system was 0.22 min−1—slightly lower than that of CoFe2O4/PMS—while Co leaching was markedly reduced. The process performed well across a broad pH range (3.0–9.0). EPR and radical-quenching experiments indicate that SO4•− and HO• play a minor role, whereas the Co(II)–PMS complex is primarily responsible for MB degradation; accordingly, common coexisting species (SO42−, Cl−, NO3−, humic acid) exert negligible effects. The catalyst also maintained strong durability across numerous repetitions. These results highlight a cost-efficient route to PMS activation by coupling CoFe2O4 with construction waste-derived supports.

Electrochemical production of acid and base from water enables their use as regenerable reagents in closed-loop processes, with attractive applications including CO2 capture or mineralization and low-temperature production of Ca(OH)2. Conventional systems utilize ion exchange membranes (IEMs) to inhibit H+/OH- recombination, which leads to high resistive losses that compromise energy efficiency and poor tolerance for polyvalent metal ions that complicates applications involving mineral resources. Here we use ion transport modeling to guide the design of a system that uses a simple porous separator instead of IEMs. Using H2 redox reactions for H+/OH- production, we demonstrate acid-base production at useful concentrations in the presence of polyvalent impurities with lower energy demand and higher current density than reported IEM-based systems. Cells can be stacked by combining H2 electrodes into a bipolar gas diffusion electrode, which recirculates H2 with near-unity efficiency. We show that the cell outputs extract alkalinity from olivine and serpentine as Mg(OH)2 and Mg3Si2O6(OH)2, which remove CO2 from ambient air to form Mg carbonates. These studies establish the principles for membrane-free electrochemical acid-base production, enabling closed-loop resource recovery and material processing powered by renewable electricity.

Renewable electricity-driven electrocatalytic nitrate reduction for ammonia production is not only beneficial for the treatment of nitrogen-containing wastewater but also facilitates the recovery of valuable resources. Metal-organic frameworks (MOFs)-based electrocatalysts have been extensively investigated as promising nitrate reduction reaction (NO3 -RR) catalysts due to their structural and compositional tunability, as well as their highly dispersed active sites. Herein, the recent research advances made in MOFs and their-derived electrocatalysts for NO3 -RR are reviewed. In the discussions, an attempt is made to highlight the advantages of MOFs and their derivatives in NO3 -RR, focusing on key aspects including catalyst design strategies, reaction mechanisms, and approaches for enhancing catalytic performance. First, microstructure regulation enhances the catalytic activity of MOFs and their derivatives, and structure-activity relationships are analyzed for NO3 -RR. Then, by integrating theoretical calculations and advanced in situ characterization, we thoroughly summarized the key intermediates, rate-determining steps, and electron/proton transfer mechanisms in the NO3 -RR reaction pathway. Finally, we provide insights into future directions and prospects regarding the design, synthesis, and evaluation of MOFs-based electrocatalysts for enhanced NO3 -RR.

Bacterial Biodegradation of Hydrocarbon-Rich Wastes: Strategies for Environmental Remediation and Resource Recovery

Substance use disorder (SUD) is a significant public health challenge with multifaceted etiologies and limited effective relapse prevention strategies. For individuals recovering from substance use disorder, self-help or personal coping mechanism has been identified as a powerful tool in achieving and maintaining recovery. However, the role of personal coping mechanism in addiction treatment remains under-explored, with limited awareness and practical application of how these practices and involvement can be integrated into recovery programs and relapse prevention particularly in the context of substance use disorder. This qualitative study explored the role of self-help or personal coping mechanism as a complementary resource for recovery in substance use disorder, especially in the cultural context of Pakistan. This study explores the experiences of 12 individuals who have maintained recovery from substance use disorder ranging from two to five years. These participants were selected from Islamabad and Khyber Pakhtunkhwa, Pakistan. Through in-depth interviews, and thematic analysis of (Braun and Clark 2012 model) participants shared their perspectives and experiences that how personal coping practices such as time management, taking shower, joining good company, no pocket money, self-control and living clean provided motivation to quit substance use, sustain recovery, and achieve inner peace and self-respect. The findings highlight personal coping as an essential resource for relapse prevention, even in rural and under-served settings where conventional healthcare for substance use disorders may be inaccessible. The study also underscores the potential of personal coping-based interventions as complementary approaches to addiction treatment and relapse prevention offering valuable insights into the development of culturally and contextually relevant recovery strategies.

Catalytic resource recovery for transformation of the wastewater industry

The transition toward a Circular Economy (CE) presents a transformative solution to global sustainability challenges by promoting resource efficiency, waste minimization, and material regeneration. This study explores the pivotal role of chemical engineering in advancing circular practices through innovative waste valorization and resource recovery strategies. Key technologies—including biomass conversion, plastic and electronic waste recycling, and food waste bioprocessing—are analyzed for their capacity to mitigate environmental impacts and close material loops. Chemical engineering principles such as catalysis, separation processes, and process intensification underpin these approaches, enhancing energy efficiency and resource utilization. Integration of digital tools, artificial intelligence (AI), and system optimization further enables real-time process control and sustainability assessment. However, widespread CE implementation faces barriers including technological limitations, high capital costs, and fragmented regulations. Overcoming these challenges requires interdisciplinary collaboration among industry, academia, and policymakers to develop scalable, cost-effective solutions. The study emphasizes the importance of next-generation catalysts, bio-based processing, and data-driven systems in achieving a resilient, low-waste industrial future. By bridging science, technology, and policy, chemical engineering can catalyze the global transition to a sustainable and circular economy.

The disposal of ammonia-laden wastewater from the palm oil industry presents a significant environmental challenge leading to water quality deterioration and adverse effects on aquatic ecosystems. The conventional methods for ammonia removal are often costly and complex necessitating the exploration of alternative solutions. This study investigates the use of palm empty fruit bunch (EFB) biochar as a sustainable adsorbent for the removal of ammonia from palm oil mill secondary effluent (POMSE). Employing Response Surface Methodology (RSM) with a Central Composite Design (CCD), the study has optimized key parameters including adsorbent dosage, initial ammonia concentration and carbonization temperature. The results demonstrated that palm EFB biochar effectively reduced ammonia levels, achieving removal efficiencies of approximately 30% at a dosage of 2 g/L and up to 43% at 4 g/L under optimal conditions (initial ammonia concentration of 292.5 mg/L and carbonization temperature of 500°C). The adsorption process conformed to the Langmuir isotherm model, indicating monolayer adsorption on a homogeneous surface. Characterization techniques such as Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) spectroscopy confirmed the structural integrity and functional interactions of the biochar with ammonia molecules. Additionally, the study explored the regeneration capabilities of the palm EFB biochar, highlighting its potential for repeated use in wastewater treatment applications. This research underscores the viability of utilizing agricultural waste as an effective and sustainable solution for ammonia removal, contributing to environmental sustainability and resource recovery in the palm oil industry.

kappa-Carrageenan-based hydrogel for leachate wastewater treatment and resource recovery

Enhanced treatment of low C/N domestic wastewater in a membrane photobioreactor: Operational control of microalgal-bacterial symbiosis for synergistic pollutant and antibiotic resistance genes removal.

Exploring the potential of sewage sludge for gasification and resource recovery: A review

Applying nutrient recovery from unused wastewater to overcome fertilizer shortage for global food security.