Solution For Recycling Research Articles

Investigation on Nitrogen Migration and Transformation during Hydrothermal Conversion of Glucose and Xylose in N-rich Solution Recycled from Hydrothermal treatment of Fiberboard

Nitrogen migration and transformation have been extensively studied during the thermochemical conversion of biomass, particularly N-rich biomass, due to concerns about nitrogen oxides pollution or the preparation of N-doped carbon materials. Nitrogen in fiberboard was extracted into an aqueous solution through low-temperature hydrothermal treatment to prepare the recycled aqueous solution. Subsequently, hydrothermal conversions of glucose and xylose were conducted in the recycled solution. The migration and transformation of nitrogen between hydrochars and aqueous phase were investigated. The results showed that the nitrogen retention rates of glucose hydrochars were higher than those of xylose hydrochars at low temperatures. As the temperature increased, the nitrogen retention rates of glucose and xylose hydrochars tended to converge, reaching their highest value at 220 °C. In hydrochars, nitrogen had a high content and was widely distributed on the surface of the carbon microspheres. The nitrogen content did not change significantly with increasing temperatures, but the nitrogen functional groups tended to become more thermostable. In addition, the char yields of glucose and xylose in fiberboard recycled solution were significantly higher than that in the ultrapure water at low temperatures, which indicates that the introduction of nitrogen promotes the formation of hydrochars. These findings favored the study on the nitrogen migration and transformation during hydrothermal conversions of lignocellulose in a N-rich environment.

Solar PV End-of-Life Waste Recycling: An Assessment of Mechanical Recycling Methods and Proposed Hybrid Laser and High Voltage Pulse Crushing Method

This research article investigates the recycling of end-of-life solar photovoltaic (PV) panels by analyzing various mechanical methods, including Crushing, High Voltage Pulse Crushing, Electrostatic Separation, Hot Knife Cutting, Water Jet Cutting, and Magnetic Separation. Each method’s effectiveness in extracting materials such as glass, silicon, metals (copper, aluminum, silver, tin, lead), and EVA was evaluated. The analysis reveals that no single method is entirely sufficient for comprehensive material recovery. Based on the data analysis, a new hypothetical hybrid method, Laser and High Voltage Pulse (L&HVP), is proposed, which integrates the precision of laser irradiation with the robustness of high voltage pulse crushing. The laser irradiation step would theoretically facilitate the removal of the ethylene-vinyl acetate (EVA) encapsulant, preparing the materials for subsequent separation. The high high-voltage pulse crushing would then selectively fragment and separate the remaining components, potentially enhancing material recovery efficiency while minimizing contamination. The proposed approach is grounded in the observed limitations of existing techniques. This method aims to offer a more comprehensive and sustainable solution for solar PV module recycling. Further research and experimentation are necessary to validate the effectiveness of the L&HVP method and its potential impact on the field of solar PV recycling.

Electrochemical recycling of recycled concrete powder: Selective recovery of calcium and silica to enable sustainable construction materials

Rapid urbanization produces billions of tons of concrete waste annually, with recycled concrete powder (RCP) posing significant challenges due to its high porosity and limited reusability. To overcome RCP’s inherent limitations and maximize resource utilization, we developed a novel “Recycled Concrete Powder Electrolyzer” for selective recovery of key components. This electrochemical method efficiently extracted Ca2＋ ions from RCP, achieving a 96% calcium extraction efficiency comparable to acid leaching. The process produced high-purity portlandite (94% purity; 65.58% yield) with crystal sizes below 30μm, ideal for cement manufacturing, while also recovering fine sand powder and silica-containing products. A Ca(NO3)2 electrolyte enhanced Ca2＋ migration and prevented membrane fouling, resulting in lower energy consumption compared to the NaNO3 system. By converting RCP into a carbon-free cement precursor and recovering valuable components, this approach demonstrates the feasibility of transforming problematic waste into sustainable construction materials. It offers a circular economy solution for concrete waste recycling, reducing landfill burden while providing a low-emission alternative for cement production.

Conversion of waste photovoltaic silicon into silicon-carbon nanocages for lithium batteries anodes preparation

As the global demand for renewable energy surges, the mass decommissioning and disposal of photovoltaic (PV) modules pose significant environmental and economic challenges. In particular, the accumulation of waste silicon from these modules calls for efficient recycling solutions. Silicon possesses a large volume expansion problem during repeated de-embedding of lithium, we instead utilize electrospinning technology to encapsulate the waste silicon in nanocages and introduce titanium dioxide and silver into the structure. A one-step calcination process produces nanoparticle-loaded nanofiber cages, with in situ TiO2 and Ag particles enhancing structural integrity. The silicon-carbon nanofiber (SATCNF) composite exhibits outstanding electrochemical performance, retaining a reversible capacity of 466.3 mAh/g after 50 cycles at a current density of 0.1 A/g. Furthermore, it demonstrates robust stability during high-rate charge and discharge cycles, maintaining substantial capacity even under elevated current densities. This work not only provides a pathway for mitigating the environmental burden of waste silicon but also contributes to advancements in LIB technology for sustainable energy storage.

Mechanism and performance of thermal radiation recycling for in-space 3D printed continuous carbon fibre-reinforced PEEK composites

ABSTRACT The benefits of space recycling lie in reducing launch mass and achieving self-sufficiency. For 3D printed continuous fibre-reinforced composites (CFRCs), a reverse melt recycling technology was proposed, involving heating resin opposite to the 3D printing path and continuously peeling-off the fibres from the melt. An infrared radiation heating recycling device suitable for a vacuum environment was designed and the temperature distributions were optimised, achieving recycling of continuous carbon fibre-reinforced polyether ether ketone (CF/PEEK) thin-walled rotational structures. The recycled filaments with diameters of 0.7 and 0.8 mm could achieve good surface quality and low pore defects. The porosity decreased from 11.2% of original samples to 5.7% of remanufactured samples, leading to improvements in mechanical properties with flexural strength and modulus increased by 4.8% and 50.8% respectively. Overall, the recycling technology emphasised a non-degradation recycling solution for 3D-printed CFRCs in space to form a full lifecycle application model for space composites.

Pollutant emission during pyrolysis of waste wind turbine blades: Nitrogen-containing components and polycyclic aromatic hydrocarbons

Serious attention was lacked for various pollutants formed in both gas and tar phase during pyrolysis recycling of waste wind turbine blades (WWTB), especially for components of carcinogenic bisphenol A (BPA) and potentially toxic polycyclic aromatic hydrocarbons (PAHs) in tar. Pyrolysis temperature within 400–600 °C would significantly impact pollutant formations. Additionally, CO2 had a potential to mitigate pollutants emission as an economic alternative for N2. This article investigated the influence of these factors on nitrogenous and PAHs components during WWTB pyrolysis through fixed bed and thermogravimetric experiments. The results showed that NO2 was dominated in nitrogen containing pollutants and was related to the evolution of pyrrole nitrogen oxides. It was found 550 °C as a turning temperature, at which the polycondensation reaction appeared significantly. This resulted in a markedly increase for toxic N-PAHs in tar. At this temperature, CO2 could be used to mitigate nitrogen pollutants. 25% CO2 reduced NOX emission about 26% and selectively promoted NH3 releasing to over 4.3 times and depressed HCN generating to 0.6 times. Moreover, the primary depolymerization product of organic pact in WWTB was BPA. Increasing residence time, temperature and CO2 concentration were beneficial for converting hazardous BPA to high valued P-Isopropenylphenol (IPP). The value of IPP:BPA could increase to over 2 in this experiment. It was aimed to provide not only an evaluation for the yield and migration of pollutants, but also an cleaner recycling solution through graded pyrolysis WWTB to mitigate pollution and maximize the value of by-products.

Optimization of the rural domestic waste recycling network based on the path planning site selection model

IntroductionIn the context of rural revitalization strategies, effectively managing rural waste is a critical task for achieving ecological environmental sustainability. The current state of garbage collection and transportation is examined in this paper, focusing on the rural waste management practices in Dongfeng County, Liaoyuan City, Jilin Province, through mathematical modeling.MethodsBy analyzing the rural domestic waste collection network, the volume of waste generated at various points is fuzzified using the fuzzy mathematical theory.ResultsThe results of path optimization for waste collection and transportation were derived from a case study, demonstrating the feasibility and practicality of the rural domestic waste recycling network model.DicussionAdditionally, sensitivity analysis was conducted to assess the impact of changes on the total cost. Potential solutions for rural waste recycling and treatment are offered in this paper, providing valuable insights for the development of a rural domestic waste recycling network in Jilin Province.

Life cycle assessment of recycling waste crystalline silicon photovoltaic modules: A comparison between traditional and green solvent recycling processes

Crystalline silicon photovoltaic (PV) modules that have reached the end of their service life, if not effectively recycled, result in the loss of valuable resources such as silicon, silver, aluminum, and others. Moreover, improper disposal can lead to long-term environmental pollution. Therefore, the development of efficient and green recycling technologies for waste PV modules has become a key focus of current research. In this study, a life cycle assessment (LCA) of green solvent recycling (GSR) and traditional recycling technologies was conducted using the ReCiPe 2016 Mid-point evaluation method. The energy and resources consumed, along with the environmental impacts generated, were comparatively analysed, and their resource recovery benefits were calculated. Results show that GSR performs well in terms of environmental impact and even better in terms of resource recovery benefits. Leaching with 1,3-dimethyl-2-imidazolidinone (DMI) solvents reduces global warming potential by 487 kg CO2 eq compared to nitric acid used in chemical recycling. Deep eutectic solvents (DES) achieve higher leaching rates of up to 99 %, compared to metals recovered via mechanical separation, and reduce terrestrial ecotoxicity by 742 kg of 1,4-DCB. Of all energy and resource inputs, electricity consumption contributes the most to environmental impacts. In summary, this study offers a more environmentally friendly and effective recycling solution for the PV industry, supporting its green transformation and sustainable development.

Promoting Sustainable Household Engagement in Recycling via Blockchain-Based Loyalty Program

Recycling plays a crucial role in impacting national GDP and environmental sustainability. Given the complexities inherent in recycling processes, technology serves as a driving force for advancing and optimizing these practices. In the Kingdom of Saudi Arabia, substantial initiatives are underway to foster a green environment and promote a circular economy. However, at the time of writing this paper, existing regulations mandate recycling primarily for business sectors, with no corresponding requirements for household waste collection or segregation. As a result, a significant portion of recyclable waste remains unprocessed. This paper expands upon earlier studies carried out in Jeddah, analyzing the obstacles and variables impacting sustainable recycling solutions, along with the essential conditions to boost household involvement in recycling. This study explores the potential of blockchain technology to improve household engagement by developing a blockchain-based loyalty program. The proposed system leverages the decentralized, immutable, and transparent features of blockchain technology to reward individuals with tokens for the recycling waste they produce, thereby facilitating token tracking across the recycling value chain and enhancing transparency in the circular economy. This article delves into the technical architecture of the loyalty program, aligning its domain model elements with blockchain design heuristics and integrating it with a mobile application that aims to boost recycling engagement by applying social economy principles. This innovative approach promises to overcome the current regulatory and motivational barriers, as well as promote sustainable recycling habits at the household level.

Dissolution of nanoparticulate IrO2 in dilute acidic baths through a pre-reduction step: A method to recover Ir from electrocatalytic/catalytic bodies

We report a process for recycling Ir-based nanosized electrocatalysts through dissolution of Ir under mild conditions (in dilute acidic media at ∼100 °C) and show that otherwise corrosion-resistant Ir-Oxide nanoparticles may be activated for dissolution in dilute HCl using a pre-reduction step. Effects of the reaction parameters such as the type of reducing agent, dissolution bath composition, reaction temperature, etc. was investigated. Further, structural characterizations to investigate the effect of the prereduction step on the Ir-Oxide and on the dissolved Ir species were made. The dissolved Ir was processed further to synthesize a new Ir-Oxide electrocatalyst exhibiting electrochemical performance (mass activity for oxygen evolution reaction) similar to that of the commercial Ir-Oxide. The study provides a recycling solution for the Ir-based electrocatalysts from relevant catalytic bodies and may be used for achieving sustainable acidic electrolyzers.

A Business Management Model in the Circular Economy: Technological Solutions for Plastic Recycling

Objectives: this article develops a model for managing business processes in a circular economy using technologies for plastic recycling. Theoretical Framework: The theoretical idea and basis of the article consists in the development of project management methodology, process approach in the closed-loop economy, development of methods and economic tools aimed at effective resource management taking into account waste reduction and increased reuse of plastic fractions in Municipal Solid Waste (MSW). The application of digital technologies and solutions in the context of business process management in the field of plastics recycling will be substantiated, which will allow to identify new opportunities and reserves for optimising business processes in this field, increasing the efficiency of resource use, improving the environment and reducing costs. Method: the work uses a project approach, a process approach, digital modeling methods, and the “polluter pays” method. To implement the process approach, it is proposed to use the concept of Business Process Management (BPM). Competent business process management allows the company to react quickly to changing market conditions and customer orientation. Digital modelling in this paper means the representation of actions in the form of business processes in the organisation of solid waste management, the 'polluter pays' method means the economic assessment and accounting of environmental damage in waste management in the costs of business processes. Results and Discussion: The results of the study can be used to introduce the process approach to plastics recycling in individual regions and countries for the development of a green economy. According to the estimates of the authors, the optimisation and cost reduction of business processes, taking into account the environmental factor and the increase of the revenue part of the project from the reuse and inclusion in the economic turnover of plastic waste recycling products on the scale of the considered city (population of 1800 thousand people, area of 2856 ha, 18.14 tonnes of plastic waste accumulated per day) will reduce the costs of business process management by more than 200 thousand euros. Research Implications: the results of the study can be used to justify projects for the processing and recycling of solid municipal waste, including plastic waste, to introduce environmentally friendly production, to reduce the negative impact on the environment, to develop a process approach to the organisation of all activities for the collection of plastic waste in the city, district. In addition, the application of the proposed approach allows to obtain economic benefits for companies through the sale of secondary resources for the processing of plastic waste, as well as to reduce the negative impact on the environment. Originality/ Value: The originality of the research and its value lies in a new scientific formulation of the problem of reducing environmental pollution from plastic waste through the use of business processes in the field of plastic recycling and digital solutions, as well as the possibility of practical application of the results obtained in the field of green economy.

Enhancing physico-chemical water quality in recycled dairy effluent through microbial consortium treatment

The dairy industry, notorious by generating wastewater rich in organic and nitrogenous content, necessitates sustainable recycling solutions. Biological treatment emerges as a cost-effective and chemical-free alternative. This study delves into the potential of microbial consortium, a microbial consortium, for recycling dairy effluent, aiming at water reclamation and environmental sustainability. Effluent samples from Madurai's Dairy Industry underwent microbial consortium treatment in a recycling prototype, with treatment efficacy assessed through physicochemical parameters and contaminant removal efficiency.Guided by a biodegradability index of 4.51, the study showcased EM's impact, revealing a notable decrease in pH levels, fostering an alkaline environment (2.35 ± 0.06 ppt). Dissolved oxygen increased significantly to 4.50 ppm, indicating improved aerobic conditions. EM treatment led to substantial reductions in calcium (53 %), magnesium (95 %), nitrogen (22 %), sulfate (79 %), phosphate (86 %), BOD (78 %), and COD (82 %). In contrast, dairy effluent treated without microbial consortium during the sludge activation process exhibited negligible water quality improvement.These findings underscore microbial consortium efficacy in advancing biological treatment of dairy effluent, demonstrating a significant reduction in contaminants and showcasing its potential for sustainable water reclamation. Improved alkalinity, dissolved oxygen, and nutrient content further signify positive impacts on ecosystem health. Microbial consortium emerges as a promising avenue for recycling dairy effluent, offering an economically viable and environmentally friendly solution. The study emphasizes the crucial role of microbial treatments in achieving efficient water reclamation, contributing to a cleaner and sustainable environment. Future research and broader implementation of microbial consortium in dairy industry wastewater management are recommended for enhanced environmental benefits.

Advanced E-Waste Facility Locator: Harnessing Convolutional Neural Networks for Sustainable Environmental Impact and Recycling Solutions

Advanced E-Waste Facility Locator: Harnessing Convolutional Neural Networks for Sustainable Environmental Impact and Recycling Solutions

Modern Methods of Asbestos Waste Management as Innovative Solutions for Recycling and Sustainable Cement Production

Managing asbestos waste presents a significant challenge due to the widespread industrial use of this material, and the serious health and environmental risks it poses. Despite its unique properties, such as resistance to high temperatures and substantial mechanical strength, asbestos is a material with well-documented toxicity and carcinogenicity. Ensuring the safe removal and disposal of asbestos-containing materials (ACM) is crucial for protecting public health, the environment, and for reducing CO2 emissions resulting from inefficient waste disposal methods. Traditional landfill disposal methods have proven inadequate, while modern approaches—including thermal, chemical, biotechnological, and mechanochemical methods—offer potential benefits but also come with limitations. In particular, thermal techniques that allow for asbestos degradation can significantly reduce environmental impact, while also providing the opportunity to repurpose disposal products into materials useful for cement production. Cement, a key component of concrete, can serve as a sustainable alternative, minimizing CO2 emissions and reducing the need for primary raw materials. This work provides insights into research on asbestos waste management, offering a deeper understanding of key initiatives related to asbestos removal. It presents a comprehensive review of best practices, innovative technologies, and safe asbestos management strategies, with particular emphasis on their impact on sustainable development and CO2 emission reduction. Additionally, it discusses public health hazards related to exposure to asbestos fibers, and worker protection during the asbestos disposal process. As highlighted in the review, one promising method is the currently available thermal degradation of asbestos. This method offers real opportunities for repurposing asbestos disposal products for cement production; thereby reducing CO2 emissions, minimizing waste, and supporting sustainable construction.

Utilizing Used Cooking Oil for Aromatherapy Candle Production

Background: Environmental pollution from used cooking oil poses significant challenges. Specific Background: Improper disposal of this waste contributes to ecological damage, highlighting the need for effective recycling solutions. Knowledge Gap: Community awareness and skills in transforming used cooking oil into valuable products are limited. Aims: This study aimed to train local residents in recycling used cooking oil into aromatherapy candles, reducing pollution and enhancing economic prospects. Results: The training, facilitated by university students, successfully informed participants about the hazards of used cooking oil and demonstrated candle-making. Participants reported high satisfaction and a willingness to apply their new skills. Novelty: This initiative presented a practical method for converting waste into a marketable product, addressing both environmental and economic issues. Implications: The program not only raised environmental awareness but also empowered the community with sustainable business opportunities, fostering innovation in waste management and improving local economies. Highlights : Pelatihan mengajarkan keterampilan mengolah limbah minyak menjadi produk bernilai. Inisiatif ini meningkatkan kesadaran lingkungan di masyarakat. Produk lilin aromaterapi berpotensi meningkatkan perekonomian lokal. Keywords: Pencemaran, Minyak, Lilin, Aromaterapi, Pelatihan

Asymmetrically Coordinated Cu Dual-Atom-Sites Enables Selective CO2 Electroreduction to Ethanol.

Electrochemical reduction of CO2 (CO2RR) to value-added liquid fuels is a highly attractive solution for carbon-neutral recycling, especially for C2+ products. However, the selectivity control to preferable products is a great challenge due to the complex multi-electron proton transfer process. In this work, a series of Cu atomic dispersed catalysts are synthesized by regulating the coordination structures to optimize the CO2RR selectivity. Cu2-SNC catalyst with a uniquely asymmetrical coordinated CuN2-CuNS site shows high ethanol selective with the FE of 62.6% at -0.8V versus RHE and 60.2% at 0.9V versus RHE in H-Cell and Flow-Cell test, respectively. Besides, the nest-like structure of Cu2-SNC is beneficial to the mass transfer process and the selection of catalytic products. In situ experiments and theory calculations reveal the reaction mechanisms of such high selectivity of ethanol. The S atoms weaken the bonding ability of the adjacent Cu to the carbon atom, which accelerates the selection from *CHCOH to generate *CHCHOH, resulting in the high selectivity of ethanol. This work indicates a promising strategy in the rational design of asymmetrically coordinated single, dual, or tri-atom catalysts and provides a candidate material for CO2RR to produce ethanol.

Removal of iron and aluminum from hydrometallurgical NMC-LFP recycling process through precipitation

There is a need to develop removal strategies for typical battery impurities–iron and aluminum–from actual hydrometallurgical recycling solutions. In this work, the investigated solution originated from lithium nickel manganese cobalt oxide (NMC) rich black mass, while iron phosphate (LFP) was used as an in situ reductant. It was found that the presence of phosphate ions supported selective iron precipitation already at pH = 2.0 (T = 60 °C, t = 3 h, NaOH), with nearly complete iron removal (97.8 %). The precipitate was rich in iron (21.5 wt%) and phosphorus (13.4 wt%); it also contained 0.7 wt% Ni and 0.3–0.4 wt% Mn, Co, Al, and Li. It is suggested that the presence of phosphate in minor amounts may cause this co-precipitation of battery metals. With the aim of combined precipitation of iron (100 %) and aluminum (91.0 %), the pH was increased up to 4.5. Although 90.8 % of fluoride precipitated, the remaining fluorides may have kept the aluminum partially in soluble form as Al-F complexes. The formed precipitate had lower iron (18.4 wt%) and phosphorus (11.4 wt%) content, whereas the impurity contents and thus the battery metals losses were slightly higher: Ni, Mn, Co, Al, and Cu were each between 1.1–1.9 wt% and Li and F < 1 wt%. In the precipitates investigated, iron was found predominantly as iron phosphate (FePO4), whereas a minor fraction also precipitated as iron fluoride (FeF3). The precipitated aluminum existed mainly as AlOOH. The results presented here will help to build iron and aluminum removal strategies for industrial battery recycling solutions, and also provide insights into the dominant iron and aluminum phases forming the precipitates.

Development of a sustainable stabilized macadam road base using steel slag as supplementary cementitious material

As the main waste product of iron and steel industry, steel slag possesses considerable cementitious activity, making it a promising alternative to cement in Cement Stabilized Macadam (CSM). However, CSM was inevitably exposed to groundwater and rainwater when served as the pavement base course, leading to concerns over poor early strength and potential pollutant leakage, which are the main factors that may hinder the widespread utilization of steel slag in CSM base. To address these issues, this study investigated the feasibility of using steel slag powder to produce CSM. Steel Slag Powder-Cement Stabilized Macadam (SSCSM) samples were prepared and the hydration products, microstructure, mechanical properties, water damage resistance and heavy metal ions leaching behavior were investigated. The results show that the nucleation effect of steel slag powder accelerates the early hydration, but the C-S-H produced by hydration is not sufficient to form a stable hydration product network, so the microstructure of SSCSM is looser than that of CSM. The addition of steel slag powder improved the shrinkage performance of SSCSM, and the mechanical properties and heavy metal ion leaching concentration of SSCSM meet the engineering application requirements when the steel slag powder replacement level does not exceed 30 %. It was also found that the addition of steel slag powder promoted the development of pores in SSCSM samples after dry-wet cycles, resulting in the reduction of water damage resistance. Compared with conventional CSM, the use of SSCSM can not only reduce 4 % of raw material cost and 23.5 % of equivalent CO2 emission, but also mitigate the heavy metal ions leaching risk associated with steel slag, making it an effective and sustainable solution for steel slag recycling.

Integrating microwave pyrolysis and hydrotreating for converting low-density polyethylene into jet fuel

With the increasing plastic waste and its environmental impact, finding effective recycling solutions is essential. Cracking plastic waste followed by hydrogenation could be a promising method for producing jet fuels. In the present work, microwave-assisted pyrolysis (MAP) with MgO combined with hydrotreating with a Ni/Biochar catalyst was firstly proposed to convert low-density polyethylene (LDPE) into jet fuel. The pyrolysis process yielded 48.5 wt% of liquid product, with C5−C15 hydrocarbons and olefins accounting for 87.6% and 65.5%, respectively. During the hydrotreating process with 10% Ni/Biochar at 300°C of temperature and 2 MPa of initial H2 pressure, the pyrolysis oil was successfully hydrotreated, resulting in 98.4% paraffins and 1.6% aromatics with liquid yield of 80.6 wt%. Among them, C5−C15 hydrocarbons created 96.1%. The kinetic analysis indicated an activation energy of 89.9 kJ/mol for hydrogenated LDPE pyrolysis oil (HPPO). Characterization of the Ni/Biochar catalyst after reaction showed a BET surface area of 438 m2/g, similar to that of the fresh catalyst, with minimal coke formation noted via XRD, TEM, and TG analyses. XPS and FTIR indicated negligible oxidation of Ni0 during hydroprocessing. After 6 cycles, the catalyst remained high abundance for paraffins and C5−C15 hydrocarbons, namely, 98.4% and 94.0%, respectively, demonstrating its stability.

Effect of fly ash on mechanical properties and microstructural behaviour of injected moulded recycled polypropylene composites

The global challenges of plastic waste and fly ash accumulation demand innovative recycling solutions. In Malaysia, the consumption of 11.2 million tonnes of coal annually generates approximately 2 million tonnes of fly ash, while the recycling of Polypropylene (PP) is hindered by thermo-oxidative and shear-induced degradation during mechanical recycling, resulting in reduced mechanical properties. This study addresses these issues by fabricating recycled PP composites incorporating varying fly ash contents, using a single cycle of mechanical recycling with extrusion and injection moulding methods. The composites were comprehensively tested for tensile, flexural, and compressive strengths, as well as microstructural behaviour. The results reveal a complex relationship between fly ash content and mechanical performance: while tensile strength decreases with increasing fly ash, flexural strength and strain peak at 5 % and 9 % fly ash, respectively. Compressive strength also shows a slight increase up to 7 % fly ash, indicating an optimal range for enhancing mechanical performance. Furthermore, mathematical models were proposed to predict the mechanical properties of rPP – fly ash composites, providing a valuable tool for future material design. These findings demonstrate that optimization of fly ash content can mitigate the effects of polymer degradation, offering a sustainable solution to improving the mechanical performance of this composite.