Waste Valorization Research Articles

Deactivation Mechanism of Spent TiO2-Based Selective Catalytic Reduction (SCR) Catalysts and State-of-the-Art Recycling Technologies.

Nitrogen oxides (NOx) make up a group of gases that are mainly formed during the combustion of fossil fuels at high temperatures. NOx contributes to environmental degradation by forming acid rain and enhancing global warming. Exposure to air with a high concentration of NOx can aggravate respiratory diseases, particularly asthma. The elimination of NOx in practical applications mainly proceeds through selective catalytic reduction (SCR) of NOx with NH3 to harmless N2 and H2O. One practical issue of the SCR process is the deactivation of TiO2-based SCR catalysts. In addition, growing numbers of spent SCR catalysts present a serious waste-management challenge for recyclers at end of life. It is therefore crucial to disclose the deactivation mechanism of the spent TiO2-based NH3-SCR catalysts and propose effective recycling technologies for waste valorization. Here we outline the catalyst deactivation pathways for TiO2-based SCR catalysts and critically review methods of improving the direct sustainability of spent catalysts, in areas such as direct regeneration and recovery of spent catalysts. Through this review, the challenges, solutions, and future strategies for handling spent SCR catalysts are clarified for future studies of application on an industrial scale.

Addition of Carrot Pomace to Enhance the Physical, Sensory, and Functional Properties of Beef Patties

The global challenge of food waste necessitates innovative solutions, such as incorporating carrot pomace, a nutrient-rich by-product of carrot juice production, into beef patties to enhance their nutritional and functional properties. This study evaluated beef patties with carrot pomace added at 0%, 1.0%, 3.0%, and 4.2%, analyzing the proximate composition, pH, color, cooking yield, water-holding capacity (WHC), texture, and sensory attributes. Adding 3.0% and 4.2% pomace significantly reduced the moisture content by 5.5% and 3.3%, respectively, and decreased redness by 40% in the 4.2% patties. The cooking yield increased by 13.9% and 22.8%, and WHC improved by 8.5% and 15.7%, respectively, with these additions. The textural properties showed substantial reductions in hardness, cohesiveness, gumminess, and chewiness, particularly at 4.2%. The sensory evaluation indicated no significant differences in appearance, aroma, taste, or overall liking for patties with up to 3% pomace. In comparison, patties with 4.2% pomace received lower scores for overall liking and firmness. These findings suggest that incorporating up to 3% carrot pomace in beef patties enhances their functional properties and dietary fiber content without compromising the sensory quality. This offers a sustainable and practical approach to food waste valorization.

Pasta Enriched with De-oiled Sesame and Yellow Pepper Flours: Evaluation of Physicochemical Properties, Protein Quality, and Antioxidant Potential

Valorization of waste as a sustainable food additive to produce value-added products is a recent interest. De-oiled sesame flour (DSF) is underutilized despite its rich protein, fiber, and phenols content. Pasta has a poor nutritional value but is a good vehicle for fortification. Therefore, pasta was enriched with DSF at 10%, 20%, and 30%, in addition to 5% yellow pepper flour (YPF) to improve the taste (S10, S20, and S30, respectively). The enriched pasta was compared to control pasta (S0) made from 100% durum wheat semolina concerning the sensory attributes, cooking quality, physicochemical properties, and microstructure. S20 pasta demonstrated good cooking properties and a texture profile similar to the control, with high sensory appeal. It had the lowest cooking loss (7.60±0.10), gumminess (39.50±5.12 g), and chewiness (0.62±0.09 mJ), the highest water absorption and volume expansion (101.30±1.27% and 295.00±7.07%), a shorter cooking time (10.05±0.71 min) and hardness (73.00±5.66 g), with a moderate cohesiveness (0.54±0.03) (p<0.05). DSF increased the protein content of the enriched pasta significantly compared to the control (14.40±0.57g to 16.90±0.57g versus 13.20±0.28 g/100g). Besides, the protein quality was improved by adding 20% DSF: The essential amino acid index increased from 62.76±0.05% to 73.11±0.95% in S20 (p<0.05). Furthermore, the antioxidant activity was increased from 1.67±2.12% (control) to 28.75±1.53% (S20) (p<0.05). Besides, iron, calcium, and zinc were increased considerably (p<0.05). De-oiled sesame flour at 20% (S20) is a promising additive for pasta producers that offers acceptable physical changes, high nutritional value, and enhanced protein quality compared to control.

Plastic Waste Valorization: Prospects for Green Hydrogen Production

: Plastic waste is a current issue worldwide that is already negatively influencing and threatening the lives of human beings, with residual micro- and nanoplastics entering water and soil bodies inducing recalcitrant pollution and health issues. The proposed perspective has been aimed to provide an overview of the potential of plastic waste valorization to green hydrogen and carbonaceous nanostructures. The overall concept additionally includes the utilization of the generated carbonaceous nanostructures to design advanced functional materials in combination with the obtained green hydrogen from plastic waste in a number of batch-to-flow catalytic hydrogenations to close the circle of sustainable integrated valorization of plastic waste. The concept also includes insightful Life-Cycle Assessment (LCA) and techno-economic studies in order to select the most relevant lines from the sustainability and cost-competitive standpoints.

Mortars produced with recycled aggregates from construction and demolition waste – analysis and construction site application

The valorisation of construction and demolition waste (CDW) as secondary raw material is an important step towards enhancing sustainability in the construction sector, combining environmental benefits with circular economy and sustainable management.The aim of this work is to analyse several mortars produced with different percentages of replacement of natural aggregates (NA) by recycled aggregates (RA) and propose a mix design methodology. First, an extensive literature review was performed and several studies conducted in recent years have been compiled, focusing on RA produced from CDW and incorporated as recycled fine aggregates in mortar matrices. Several properties have been analysed, such as: compressive, flexural and bond strengths, Young’s modulus, capillarity, and shrinkage. Results are discussed, in order to characterize: (i) the binder paste, considering the combination of binders and the respective water-binder and binder-aggregates ratios; and (ii) the different RA and respective proportions (through replacement ratio), quantifying the respective influences on mechanical and durability properties. Subsequently, a methodology is proposed that integrates the aforementioned parameters, thereby enabling the design of mortars with different binders, RA and proportions, tailored to the specific requirements of each application.It has been concluded that, depending on the binder performance (mainly resultant of binder type, combined with its proportion, and the water-binder ratio), RA can have variable influence on the mortar properties. Furthermore, by dividing the mortars under study into groups defined by Feret coefficient intervals according to the binder used and associating the RA with correction coefficients that do not exceed 0.15 per percentage of incorporated RA, it is possible to design the mortar mix according to the desired mechanical properties.

Sustainable valorization of agricultural waste into bioplastic and its end-of-life recyclability for biochar production: Economic profitability and life cycle assessment

While the industrial sectors have recently focused on producing bioplastic materials, the utilization of edible feedstocks and the generation of wastes and byproducts during the bioplastic synthesis process might delay achieving the environmental sustainability strategy. To overcome these limitations related to bioplastic industrialization, this study focuses on synthesizing bioplastics from waste sources, followed by recycling its end-of-life (e.g., spent and exhausted) material into biochar. Sweet potato peel waste, banana pseudo-stems, and cooking oil waste were used to extract starch, cellulose, and glycerol (a plasticizer) involved in bioplastic manufacturing, respectively. It was found that the cellulose content of 30% w w–1 in bioplastic maintained the best physicochemical, mechanical, and biodegradability properties, recommending a high applicability for food packaging. The exhausted bioplastic was then pyrolyzed to maintain a biochar yield of 32.60±0.89%, avoiding the risk of secondary pollution from waste material disposal. This biochar was utilized to treat wastewater generated from the bioplastic synthesis process, showing the optimum adsorption factors of biochar dosage= 3.81 g L–1, time= 102 min, and solution pH= 7.81. The combined bioplastic production, waste pyrolysis, and wastewater treatment scheme could earn profits from biomaterial sales, carbon credit, and pollution reduction shadow price, maintaining a 6.78-year payback period and a 12.09% internal rate of return. This integrated framework depicted better contributions to the mid-point/end-point life cycle assessment impact categories than the only bioplastic production scenario. This study contributed towards achieving several sustainable development goals (SDGs), including SDG#3: human health protection, SDG#6: wastewater treatment, and SDG#12: waste recycling.

Sustainable management of rice by-products: Environmental challenges, industrial applications, and circular bio-economy innovations

The agricultural sector plays an essential role in both human and economic growth, offering sustenance, employment, income, raw materials, technological progress, and sustainability. The growing awareness of the necessity to enhance agricultural production is gaining attention, primarily driven by the imperative to adequately nourish the continuously expanding global population. Diverse agricultural practices are causing harmful environmental consequences, posing a significant risk to ecological stability through issues such as soil degradation, water pollution, habitat loss, and biodiversity decline. Timely and effective agricultural waste management has become essential for preventing adverse environmental and health impacts. Biomass from rice crop harvesting and processing has been found in abundance around the world. Because of the abundance of this biomass in nature, researchers are harnessing it for various objectives, including global energy requirements, while supporting environmental sustainability. Due to this rationale, within the frameworks of emerging sustainable and circular models, the prioritization of agricultural waste valorization has gained prominence as a pivotal strategy aimed at advancing sustainable management and circular economy. This review mainly emphasizes on the rice bio-waste, its environmental and health-related issues, policies to control stubble burning, reduce pollution in the air, and sustainable management of the bio-waste into wealth using different approaches worldwide. We also investigated the potential contribution of rice-by-products wastes to bioenergy production (bioethanol, biogas, and biofuel), enzymes, nanoparticles, construction materials, animal husbandry, bioplastics, and other value-added products. We recommend that proper management of rice by-products may produce innovative bio-ingredients and biodegradable materials, and enhance green growth and a circular bioeconomy.

Plastic waste valorization for formic acid production: A comparison between the electrolysis and hydrogenation process

Plastic waste valorization for formic acid production: A comparison between the electrolysis and hydrogenation process

Antioxidant and neuroprotective potential of extracts from Hass avocado peel obtained through a biorefinery process: A sustainable strategy for the valorization of agro-food waste

This study presents a novel three-step biorefinery approach for extracting bioactive compounds from Hass avocado (Persea americana, Mill.) epicarp. By sequentially using supercritical CO2, CO2-expanded ethanol, and subcritical water, we efficiently recovered a diverse range of extracts with distinct phytochemical profiles and potent biological activities. Our innovative extraction strategy outperformed conventional methods, demonstrating the potential of biorefinery for sustainable valorization of agricultural byproducts. Medium and high extracts exhibited strong antioxidant and anticholinesterase activity. For example, the CO2-expanded ethanol extracts demonstrated an ABTS radical cation scavenging capacity of 3.01 ± 0.06 mmol Trolox equivalents/g and an SC50 value of 53.4 ± 1.2 μg/mL for anticholinesterase activity. These findings highlight the feasibility of integrating biorefinery processes into circular economy initiatives to create high-value bioproducts while minimizing waste.

From decay to decadence: Fungal alchemy in waste valorization

Fungal alchemy harnesses fungi's enzymatic efficiency to naturally degrade synthetic plastics. Enzymes like cutinase and lipase, secreted by Aspergillus and Penicillium, break down plastics, while lignocellulolytic enzymes and oxidant ions aid in this process. Aspergillus nidulans, Bjerkandera adusta, and Pleurotus ostreatus drive bioenergy and genetic engineering innovations for a sustainable eco-friendly approach to plastic waste management and waste valorization.

Design Process, Evaluation, and Sensitivity Analysis of an Activated Carbon Production Plant from Single-use Plastic Waste at the National University of Engineering

Objective: The objective of this study is to investigate the design process, economic evaluation, and sensitivity analysis for the construction of an activated carbon production plant from single-use plastic waste at the National University of Engineering. This project aims to transform plastic waste into a high-value-added product, thereby contributing to sustainability and aligning with circular economy principles. Theoretical Framework: The theoretical framework covers concepts related to the circular economy and sustainable waste management, emphasizing the need to reduce environmental impact through innovative alternatives such as recycling PET into activated carbon. Previous studies on pyrolysis and thermal or chemical activation of plastics for conversion into high-value materials are cited, establishing a solid foundation to contextualize the activated carbon production process. Method: The methodology adopted for this research includes a technical and economic study design based on the assessment of processes and equipment required for activated carbon production. An experimental approach is proposed, wherein plastic waste is collected, shredded, washed, dried, carbonized, activated, and finally packaged. Data collection involved detailed calculations of investment, energy consumption, and mass and energy balances for each stage of the production process. Results and Discussion: The results revealed that the project is economically viable, with a Net Present Value (NPV) of 59,733 USD and an Internal Rate of Return (IRR) of 13%. In the discussion, the project’s profitability is contextualized through a sensitivity analysis evaluating different scenarios of exchange rate and sale price. This analysis confirms that, in optimistic scenarios, the IRR can reach up to 341%, reducing the payback period to less than a year. Research Implications: The practical implications of this research include the potential to implement a circular economy model in educational institutions, promoting sustainability and efficient waste management. Theoretically, the study contributes to the field of plastic waste valorization through its transformation into activated carbon, which could positively impact sectors such as environmental management and industrial recycling. Originality/Value: This study contributes to the literature by presenting an innovative approach for plastic waste valorization into activated carbon within an educational institution, using pyrolysis and activation processes in a circular economy context. The relevance of this research lies in its practical applicability in academic settings and its potential impact on reducing plastic waste.

Food Waste to Food Security: Transition from Bioresources to Sustainability

The transition from food waste to food security is a critical component of sustainability efforts. This approach focuses on repurposing organic waste products generated throughout the food supply chain into valuable resources. Food waste, encompassing everything from agricultural residues to post-consumer waste, represents a significant untapped potential that can be harnessed to enhance food security. By implementing strategies such as composting, bioconversion, and innovative recycling technologies, biowastes can be transformed into fertilizers, animal feed, and even new food products, thus closing the loop in the food system and aiding sustainable solutions for waste valorization. This transition not only addresses environmental concerns by reducing landfill waste and greenhouse gas emissions but also contributes to economic sustainability by creating new opportunities within the food production and waste management sectors. Ultimately, transforming food waste into a resource aligns with the broader goals of a circular economy, ensuring a sustainable, resilient, and food-secure future.

From Mine Waste to Construction Materials: A Bibliometric Analysis of Mining Waste Recovery and Tailing Utilization in Construction

This article presents a comprehensive scientometric analysis of mining waste valorization, focusing on tailings utilization in construction materials from 2010 to 2024. Through examination of 1096 Web of Science publications and utilizing CiteSpace mapping and network analyses, we analyze the intellectual structure of this field. Subject category analysis reveals materials science, construction technology, and environmental engineering as the dominant disciplines, interconnected through 168 links across 64 thematic nodes. Our co-citation analysis identifies 12 major research clusters, with materials science and environmental engineering serving as primary disciplinary pillars. Keyword co-occurrence analysis of 532 nodes connected by 1181 links highlights the field’s emphasis on fly ash, concrete applications, and mechanical properties. Recent citation bursts indicate growing research focus on thermal stability, heavy metal treatment, and innovative processing methods. Through synthesizing these scientometric indicators, this review provides strategic insights for advancing sustainable construction practices through mining waste utilization. Research gaps identified include long-term durability assessment, standardization needs, and scalability challenges. By synthesizing these diverse scientometric indicators, this review provides strategic insights for researchers, industry practitioners, and policymakers, contributing to the advancement of sustainable construction practices through mining waste utilization.

Rheological behavior of nepheline syenite beneficiation waste-based mortars

The valorization of mining waste through its application as a fine aggregate in mortar production offers significant environmental advantages. However, the rheological properties of this composite system must be thoroughly investigated to evaluate the technical viability of such use. To date, no studies have been reported on the consistency and flowability of mortars incorporating nepheline syenite beneficiation waste (NSW) as a fine aggregate substitute. Therefore, the aim of this study was to examine the rheological behavior of mortars where natural fine aggregate (NFA) was partially or fully replaced by NSW. The results indicated that incorporating NSW leads to a marked increase in mortar viscosity. Notably, when substitution rates exceed 50 %, there is a substantial decline in workability, adversely affecting mortar handling. This trend was evidenced by the consistency index test, where the consistency of mortars D75 (225 mm) and D100 (219 mm) decreased significantly compared to the control mortar D0 (280 mm). Additionally, at the reference rotational speed (190.98 rpm), the measured viscosities were as follows: 4.99 Pa s (D0), 5.96 Pa s (D25), 6.96 Pa s (D50), 8.07 Pa s (D75), and 8.78 Pa s (D100), further confirming the reduction in fluidity as NSW content increased. The key properties of NSW believed to influence these results include particle size distribution, surface area, and the shape, geometry, and surface characteristics of the particles. Based on the findings, it can be concluded that NFA can be replaced by up to 50 % with NSW without significantly compromising the rheological properties of the mortar, thus promoting sustainable development through waste utilization.

Pyrolysis and beyond: Sustainable valorization of plastic waste

The recycling of plastics through pyrolysis has garnered significant attention as a waste management approach, particularly given upcoming regulations and the urgent need for absolute sustainability. This review paper evaluates pyrolysis's technological, environmental, and regulatory aspects, emphasizing the need to prioritize environmental impact over purely economic considerations. While it is recognized that financial challenges have constrained many past attempts at scaling pyrolysis systems, this paper argues that a shift in focus toward sustainability criteria is essential for the technology's long-term viability. Prioritizing environmental outcomes is critical given the pressing issues like plastic pollution, which presents significant threats to ecosystems and human health. A comprehensive assessment of environmental impacts is vital for technologies intended for large-scale deployment, ensuring that they align with global sustainability goals. This perspective is especially pertinent in light of the current United Nations Environment Programme (UNEP) global plastic pollution treaty negotiations, where there is a contentious debate over the true circularity of chemical recycling. Environmentalists and several nations advocate for significant reductions in plastic production and bans on single-use plastics. At the same time, oil-producing countries and petrochemical companies push for circularity in the plastic economy. The paper explores the promise and limitations of pyrolysis technology for valorizing plastic wastes, comparing its efficacy with other waste management methods. Biomass pyrolysis is discussed due to its significant synergies with plastic pyrolysis and its potential for carbon sequestration through biochar. However, the discussion on biomass pyrolysis is limited in scope, with the paper's primary focus on waste plastic pyrolysis. The paper discusses the challenges and opportunities in utilizing pyrolysis for waste plastics, which are considered along with regulatory and geopolitical aspects. Environmental impacts, including life cycle analysis and planetary boundary considerations, are examined to understand why pyrolysis has yet to achieve widespread adoption. A case study on Plastic Energy, SABIC, and Unilever highlights current industry status, technological advancements, and information gaps. Finally, a comprehensive framework is proposed to achieve net-zero emissions, improve air quality, and ensure absolute environmental sustainability in plastic recycling. Recommendations are provided for the plastic industry and research institutions to support the transition towards sustainable waste management practices.

Simultaneous saccharification and fermentation of municipal cardboard waste for bioethanol production using immobilized cellulases and xylanases onto Cu-MOF

This study aims to establish a cost-effective and environmentally friendly method for bioethanol production by optimizing enzymatic hydrolysis of cardboard waste, a significant component of municipal solid waste, in combination with fermentation by Saccharomyces cerevisiae. The use of a cellulases and xylanases enzyme blend, sourced from Thermobifida fusca and Bacillus pumilus, respectively, enhances saccharification efficiency. Pre-treatment with 2 % NaOH results in a substantial 66 % saccharification efficiency at a 5 % solid/substrate loading. Further improvement in hydrolysis efficiency is achieved through enzyme immobilization on Cu-BTC-MOFs, which were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Field Emission Scanning Electron Microscopy (FESEM). The immobilized enzyme blend increases saccharification efficiency to 78 %, compared to 66 % for free enzyme systems. Reusability studies demonstrate a gradual reduction in saccharification efficiency across successive cycles, reaching 71.29 % by the twelfth cycle. When applied in a simultaneous saccharification and fermentation (SSF) setup under optimized conditions, the system yields a notable bioethanol production with a yield of 0.55 g/g and a productivity of 0.20 g/L·h. This study offers potential applications in sustainable bioethanol production and waste valorization by enhancing enzymatic hydrolysis and fermentation of municipal cardboard waste. The approach demonstrates promise for scaling bioenergy production and contributes to addressing waste management challenges, supporting green energy initiatives.

Ni/PiNe Heterogeneous Catalyst from Biomass Waste: Low-Loading, Ligand-Free Suzuki-Miyaura Cross-Coupling.

An efficient Ni-based heterogeneous catalyst from pine needles urban waste valorization was designed and developed with a resource recycling strategy. The Ni/PiNe catalyst was fully characterized and tested in the Suzuki-Miyaura coupling under microwave irradiation. Although Ni is a promising candidate for replacing Pd-based catalytic systems, it generally requires a high catalyst amount and the exploitation of ligands and additives to enhance the reaction rate. On the contrary, with our new Ni/PiNe, 30 different products were efficiently synthesized with an isolated yield of up to 93%, using a very low catalyst amount and in the absence of ligands. Furthermore, the Ni/PiNe catalyst also showed good durability for consecutive cycles and an impressive TON value (1140). In addition to the catalytic efficiency in short reaction time and to the stability and durability under MW irradiation, the Ni/PiNe allowed for further optimization, achieving a low E-factor value (14.0), thus highlighting the potential in further reducing the waste and costs associated to the process.

Exploit and elucidate chaperone assisted PET hydrolase for upcycling plastics

Polyethylene terephthalate (PET) is the most abundant plastic waste in the environment. Currently, a new biocatalyst PETase, was discovered in 2016 from Ideonella sakaiensis bacteria, owned the high ability to digest PET through a mild and sustainable process. However, the high-level production of PETase in the model Escherichia coli remains a challenge and limits its application. Therefore, we employed the native molecular chaperones from Ideonella sakaiensis to improve the quality and quantity of an outstanding PETase variant, FAST-PETase (FA) at the first time. We selected GroELS from E. coli (EcG) and I. sakaiensis (IsG) using three genetic designs while the co-expressing FA with IsG chaperone increased soluble FA and elevated its activity by 25%. On the other hand, through the genome mining of I. sakaiensis, we identified a lipase secretion chaperone (IsLsC) at the upstream of native PETase. When co-expressing IsLsC and FA, the degradation efficiency toward PET film was up to 51.7 % within one day at 50 °C. More LsC-like chaperones could be explored from the sequence similarity network (SSN) with corresponding function to IsLsC. Finally, molecular docking and dynamic simulation exploited a hydrogen bond formation between FA and IsLsC to stabilizing the overall structure. The discovery of a novel chaperone offers a promising strategy for attractive PETase engaging in PET waste valorization.

Novel and sustainable valorization of biogenic waste into microbial protein based fish dietary ingredient in bioreactor: Process optimization and sustainable utilization

Waste valorization is the concept of sustainability, and microbial floc is the valorised product of sustainable aquaculture. It converts nitrogenous waste into nutritious microbial protein that can replace fish meal partially or completely as feed for aquatic animals. The current study focuses on optimizing the process of production of microbial protein using aquaculture waste in a bioreactor and its utilization as feed for genetically improved farmed tilapia (GIFT) reared in inland saline groundwater with various inclusion levels. The retention time, aeration, and microbial flocculant (chitosan) were optimized to intensify the reaction, using a response surface methodology approach based on a full factorial experimental design. The chosen responses for evaluation were crude protein (CP), crude lipid (CL), and floc volume (FV). The interaction between aeration and retention time was found to play a significant role in the percentage of crude protein and crude lipid of microbial floc (p<0.001). The floc volume was significantly influenced by retention time and chitosan concentration (p<0.05). The process was optimized with 4 days of retention time, 30 ppm of chitosan concentration, and intermittent aeration (0.5 hr aeration and 0.5 hr no aeration), which resulted good quality microbial floc with a maximum CP of 24.74 %, a maximum CL of 2.13 %, and a FV of 13.75 ml. A completely randomized design with the inclusion of 0 %, 10 %, 20 %, and 30 % microbial floc (produced in a bioreactor) in feed was followed to evaluate the growth performance of GIFT. Among these, microbial flocs with a 20 % inclusion level showed a good growth trajectory. This study has shown that 20 % microbial floc meal in the diet is optimum for the growth of GIFT in inland saline groundwater. This study sustainably supports the waste valorization concept with microbial protein production in a bioreactor that is a suitable feed for GIFT.

Agricultural waste valorisation – Novel Areca catechu L. residue blended with PVA-Chitosan for removal of chromium (VI) from water – Characterization, kinetics, and isotherm studies

Arecanut, an industrial crop prevalent in tropical regions such as India, Sri Lanka, and parts of Southeast Asia, generates significant agricultural waste during processing. This study explores a waste-to-wealth approach by incorporating arecanut organic residue into Polyvinyl alcohol (PVA) - Chitosan blends via an eco-friendly continuous stirring method to develop an adsorbent film for removing chromium (VI) from water. Morphological analyses confirmed enhanced surface area, porosity, and roughness in the blended films. XRD and FTIR analyses indicated a semi-crystalline nature with a decrease in the characteristic peak intensity of PVA and chitosan, confirming the incorporation of arecanut residue. Optimal conditions identified OR-4 film, using 0.4 g of adsorbent, achieving 88.68 % removal of 173 mg/L chromium (VI) at pH 9.0, within 45 minutes at 40°C. SEM images demonstrated significant surface roughness reduction before and after adsorption, confirming chromium adsorption. Kinetic studies revealed a pseudo-second-order model and adsorption isotherms confirmed film surface heterogeneity. This research advances eco-friendly materials for water purification and offers a sustainable solution for managing agricultural residues.