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Sustainability, Circular Economy and Waste Recycling: Advances in Materials Research

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A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Green Materials".

Deadline for manuscript submissions: closed (20 February 2024) | Viewed by 30471

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Dr. Daniela Fico

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1. National Research Council-Institute of Heritage Science (CNR-ISPC), Ecotekne Campus, s.p. 6, Lecce-Monteroni, 73100 Lecce, Italy
2. Department of Engineering for Innovation, University of Salento, Building P, Ecotekne Campus, s.p. 6, Lecce-Monteroni, 73100 Lecce, Italy
Interests: cultural heritage; analytical chemistry; materials engineering; archaeometry; innovative and green materials; additive manufacturing; rehabilitation processes; building applications; coatings; 3D printing; bio-based polymers and composites; chromatographic and spectroscopic techniques; conservation and restoration; waste recycling; circular economy
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Dear Colleagues,

Today, ecological problems impose a limited production of plastics and non-biodegradable materials and their replacement by materials with a low environmental impact. Biodegradable macromolecules and their composites are desirable candidates for a wide range of applications to overcome the difficulties of waste disposal. Moreover, one of the most crucial trends in current research on the development of new materials is associated with the use of waste raw materials or industrial by-products. This approach takes into account not only ecological issues, but also economic ones, since recycled and waste materials are significantly cheaper than virgin raw materials and their use produces low-cost end products. The substitution in industries of raw materials that must necessarily be disposed of, by-products and waste with renewable and recyclable raw materials constitutes an important transition to Sustainable Development and the Circular Economy: topics that many countries have already introduced into their environmental agenda through the creation of specific legislation.

This Special Issue aims to highlight advanced research on the development of new eco-friendly materials and new technologies for Sustainability and the Circular Economy. Topics include, but are not limited to:

Biopolymers and biocomposites from natural raw materials;
Innovative materials from recycled waste and industrial by-products;
Synthesis, preparation and processing, applications;
Characterisation, properties and potential of new biodegradable and ecofriendly materials;
Studies on durability and biodegradability under various conditions and environments;
Life cycle assessment of new materials;
Circular economy, Sustainability, Innovative and Green materials.

Original research, Review articles, Case studies and Research papers focusing on chemical, Engineering and physical processes, developed of new green materials and other investigations are accepted. Papers focusing on topics such as Sustainability, Circular Economy, and Cost-effective Technologies for different applications, are also welcome.

I look forward to receiving your contributions.

Best regards,

Dr. Daniela Fico
Guest Editor

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Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Materials is an international peer-reviewed open access semimonthly journal published by MDPI.

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Keywords

circular economy
sustainability
waste
recycling
bio-based materials
ecofriendly materials and processes
green engineering

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Sustainability, Circular Economy and Waste Recycling: Advances in Materials Research (2nd Edition) in Materials (5 articles)

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Research

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13 pages, 1067 KiB

Open AccessArticle

The Use of Lightweight Aggregates in Geopolymeric Mortars: The Effect of Liquid Absorption on the Physical/Mechanical Properties of the Mortar

by Emilia Vasanelli, Silvia Calò, Alessio Cascardi and Maria Antonietta Aiello

Materials 2024, 17(8), 1798; https://doi.org/10.3390/ma17081798 - 14 Apr 2024

Viewed by 787

Abstract

Geopolymers have been proposed as a green alternative to Portland cement with lowered carbon footprints. In this work, a geopolymeric mortar obtained using waste materials is studied. Fly ash, a waste generated by coal combustion, is used as one of the precursors, and waste glass as lightweight aggregates (LWAs) to improve the thermal performance of the mortar. The experimental study investigates the effect of varying the alkali activating solution (AAS) amount on the workability, compressive strength, and thermal conductivity of the mortar. Indeed, AAS represents the most expensive component in geopolymer production and is the highest contributor to the environmental footprint of these materials. This research starts by observing that LWA absorbs part of the activating solution during mixing, suggesting that only a portion of the solution effectively causes the geopolymerization reactions, the remaining part wetting the aggregates. Three mixes were investigated to clarify these aspects: a reference mix with a solution content calibrated to have a plastic consistency and two others with the activating solution reduced by the amount absorbed by aggregates. In these cases, the reduced workability was solved by adding the aggregates in a saturated surface dry state in one mix and free water in the other. The experimental results evidenced that free water addiction in place of a certain amount of the solution may be an efficient way to improve thermal performance without compromising the resistance of the mortar. The maximum compressive strength reached by the mortars was about 10 MPa at 48 days, a value in line with those of repair mortars. Another finding of the experimental research is that UPV was used to follow the curing stages of materials. Indeed, the instrument was sensitive to microstructural changes in the mortars with time. The field of reference of the research is the rehabilitation of existing buildings, as the geopolymeric mortars were designed for thermal and structural retrofitting. Full article

(This article belongs to the Special Issue Sustainability, Circular Economy and Waste Recycling: Advances in Materials Research)

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20 pages, 7504 KiB

Open AccessArticle

Synthesis and Surface Strengthening Modification of Silica Aerogel from Fly Ash

by Lei Zhang, Qi Wang, Haocheng Zhao, Ruikang Song, Ya Chen, Chunjiang Liu and Zhikun Han

Materials 2024, 17(7), 1614; https://doi.org/10.3390/ma17071614 - 1 Apr 2024

Cited by 3 | Viewed by 1235

Abstract

This study focuses on using activated fly ash to preparate silica aerogel by the acid solution–alkali leaching method and ambient pressure drying. Additionally, to improve the performance of silica aerogel, C₆H₁₆O₃Si (KH-570) and CH₃Si(CH₃O)₃ (MTMS) modifiers were used. Finally, this paper investigated the factors affecting the desilication rate of fly ash and analyzed the structure and performance of silica aerogel. The experimental results show that: (1) The factors affecting the desilication rate are ranked as follows: hydrochloric acid concentration > solid–liquid ratio > reaction temperature > reaction time. (2) KH-570 showed the best performance, and when the volume ratio of the silica solution to it was 10:1, the density of silica aerogel reached a minimum of 183 mg/cm³. (3) The optimal process conditions are a hydrochloric acid concentration of 20 wt%, a solid–liquid ratio of 1:4, a reaction time of two hours, and a reaction temperature of 100 °C. (4) The optimal performance parameters of silica aerogel were the thermal conductivity, specific surface area, pore volume, average pore size, and contact angle values, with 0.0421 W·(m·K)⁻¹, 487.9 m²·g⁻¹, 1.107 cm³·g⁻¹, 9.075 nm, and 123°, respectively. This study not only achieves the high-value utilization of fly ash, but also facilitates the effective recovery and utilization of industrial waste. Full article

(This article belongs to the Special Issue Sustainability, Circular Economy and Waste Recycling: Advances in Materials Research)

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14 pages, 5172 KiB

Open AccessArticle

Bio-Composite Filaments Based on Poly(Lactic Acid) and Cocoa Bean Shell Waste for Fused Filament Fabrication (FFF): Production, Characterization and 3D Printing

by Daniela Fico, Daniela Rizzo, Valentina De Carolis and Carola Esposito Corcione

Materials 2024, 17(6), 1260; https://doi.org/10.3390/ma17061260 - 8 Mar 2024

Cited by 6 | Viewed by 1570

Abstract

In this study, novel biocomposite filaments incorporating cocoa bean shell waste (CBSW) and poly(lactic acid) (PLA) were formulated for application in Fused Filament Fabrication (FFF) technology. CBSW, obtained from discarded chocolate processing remnants, was blended with PLA at concentrations of 5 and 10 wt.% to address the challenge of waste material disposal while offering eco-friendly composite biofilaments for FFF, thereby promoting resource conservation and supporting circular economy initiatives. A comprehensive analysis encompassing structural, morphological, thermal, and mechanical assessments of both raw materials and resultant products (filaments and 3D printed bars) was conducted. The findings reveal the presence of filler aggregates only in high concentrations of CBSW. However, no significant morphological or thermal changes were observed at either CBSW concentration (5 wt.% and 10 wt.%) and satisfactory printability was achieved. In addition, tensile tests on the 3D printed objects showed improved stiffness and load resistance in these samples at the highest CBSW concentrations. In addition, to demonstrate their practical application, several 3D prototypes (chocolate-shaped objects) were printed for presentation in the company’s shop window as a chocolate alternative; while retaining the sensory properties of the original cocoa, the mechanical properties were improved compared to the base raw material. Future research will focus on evaluating indicators relevant to the preservation of the biocomposite’s sensory properties and longevity. Full article

(This article belongs to the Special Issue Sustainability, Circular Economy and Waste Recycling: Advances in Materials Research)

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14 pages, 4524 KiB

Open AccessArticle

The Recovery of Vanadium Pentoxide (V₂O₅) from Spent Catalyst Utilized in a Sulfuric Acid Production Plant in Jordan

by Hiba H. Al Amayreh, Aya Khalaf, Majd I. Hawwari, Mohammed K. Hourani and Abeer Al Bawab

Materials 2023, 16(19), 6503; https://doi.org/10.3390/ma16196503 - 30 Sep 2023

Cited by 1 | Viewed by 2262

Abstract

Vanadium is a significant metal, and its derivatives are widely employed in industry. One of the essential vanadium compounds is vanadium pentoxide (V₂O₅), which is mostly recovered from titanomagnetite, uranium–vanadium deposits, phosphate rocks, and spent catalysts. A smart method for the characterization and recovery of vanadium pentoxide (V₂O₅) was investigated and implemented as a small-scale benchtop model. Several nondestructive analytical techniques, such as particle size analysis, X-ray fluorescence (XRF), inductively coupled plasma (ICP), and X-ray diffraction (XRD) were used to determine the physical and chemical properties, such as the particle size and composition, of the samples before and after the recovery process of vanadium pentoxide (V₂O₅). After sample preparation, several acid and alkali leaching techniques were investigated. A noncorrosive, environmentally friendly extraction method based on the use of less harmful acids was applied in batch and column experiments for the extraction of V₂O₅ as vanadium ions from a spent vanadium catalyst. In batching experiments, different acids and bases were examined as leaching solution agents; oxalic acid showed the best percent recovery for vanadium ions compared with the other acids used. The effects of the contact time, acid concentration, solid-to-liquid ratio, stirring rate, and temperature were studied to optimize the leaching conditions. Oxalic acid with a 6% (w/w) to a 1/10 solid-to-liquid ratio at 300 rpm and 50 °C was the optimal condition for extraction (67.43% recovery). On the other hand, the column experiment with a 150 cm long and 5 cm i.d. and 144 h contact time using the same leaching reagent, 6% oxalic acid, showed a 94.42% recovery. The results of the present work indicate the possibility of the recovery of vanadium pentoxide from the spent vanadium catalyst used in the sulfuric acid industry in Jordan. Full article

(This article belongs to the Special Issue Sustainability, Circular Economy and Waste Recycling: Advances in Materials Research)

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20 pages, 2347 KiB

Open AccessArticle

Sugar-Free, Vegan, Furcellaran Gummy Jellies with Plant-Based Triple-Layer Films

by Anna Stępień, Joanna Tkaczewska, Nikola Nowak, Wiktoria Grzebieniarz, Urszula Goik, Daniel Żmudziński and Ewelina Jamróz

Materials 2023, 16(19), 6443; https://doi.org/10.3390/ma16196443 - 27 Sep 2023

Cited by 3 | Viewed by 2703

Abstract

Increasing consumer awareness of the impact of nutrition on health and the growing popularity of vegan diets are causing a need to look for new plant-based formulations of standard confectionery products with high energy density and low nutritional value, containing gelatin. Therefore, the aim of this study was to develop vegan and sugar-free gummy jellies based on an algae-derived polysaccharide—furcellaran (FUR). Until now, FUR has not been used as a gel-forming agent despite the fact that its structure-forming properties show high potential in the production of vegan confectionery. The basic formulation of gummy jellies included the addition of soy protein isolate and/or inulin. The final product was characterized regarding its rheological, antioxidant, mechanical and physicochemical properties. Eco-friendly packaging for the jellies composed of a three-layer polymer film has also been developed. It was observed that the highest values of textural parameters were obtained in jellies containing the addition of soy protein isolate, whose positive effect was also found on antioxidant activity. Before drying, all furcellaran-based gel systems showed G’ and G” values characteristic of strong elastic hydrogels. Storing jellies for a week under refrigeration resulted in an increase in hardness, a decrease in moisture content and reduced water activity values. Overall, our study indicates the high potential of furcellaran both as a gelling agent in confectionery products and as a base polymer for their packaging. Full article

(This article belongs to the Special Issue Sustainability, Circular Economy and Waste Recycling: Advances in Materials Research)

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21 pages, 16237 KiB

Open AccessArticle

Carbon-Fiber-Recycling Strategies: A Secondary Waste Stream Used for PA6,6 Thermoplastic Composite Applications

by Marco Valente, Matteo Sambucci, Ilaria Rossitti, Silvia Abruzzese, Claudia Sergi, Fabrizio Sarasini and Jacopo Tirillò

Materials 2023, 16(15), 5436; https://doi.org/10.3390/ma16155436 - 3 Aug 2023

Cited by 3 | Viewed by 1769

Abstract

With a view to achieving sustainable development and a circular economy, this work focused on the possibility to valorize a secondary waste stream of recycled carbon fiber (rCF) to produce a 3D printing usable material with a PA6,6 polymer matrix. The reinforcing fibers implemented in the research are the result of a double-recovery action: starting with pyrolysis, long fibers are obtained, which are used to produce non-woven fabrics, and subsequently, fiber agglomerate wastes obtained from this last process are ground in a ball mill. The effect of different amounts of reinforcement at 5% and 10% by weight on the mechanical properties of 3D-printed thermoplastic composites was investigated. Although the recycled fraction was successfully integrated in the production of filaments for 3D printing and therefore in the production of specimens via the fused deposition modeling technique, the results showed that fibers did not improve the mechanical properties as expected, due to an unsuitable average size distribution and the presence of a predominant dusty fraction ascribed to the non-optimized ball milling process. PA6,6 + 10 wt.% rCF composites exhibited a tensile strength of 59.53 MPa and a tensile modulus of 2.24 GPa, which correspond to an improvement in mechanical behavior of 5% and 21% compared to the neat PA6,6 specimens, respectively. The printed composite specimens loaded with the lowest content of rCF provided the greatest improvement in strength (+9% over the neat sample). Next, a prediction of the “optimum” critical length of carbon fibers was proposed that could be used for future optimization of recycled fiber processing. Full article

(This article belongs to the Special Issue Sustainability, Circular Economy and Waste Recycling: Advances in Materials Research)

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15 pages, 9876 KiB

Open AccessEditor’s ChoiceArticle

The Effect of Process Conditions on Sulfuric Acid Leaching of Manganese Sludge

by Jafar Safarian, Ariel Skaug Eini, Markus Antonius Elinsønn Pedersen and Shokouh Haghdani

Materials 2023, 16(13), 4591; https://doi.org/10.3390/ma16134591 - 25 Jun 2023

Viewed by 1577

Abstract

Manganese sludge, an industrial waste product in the ferroalloy industry, contains various components and holds significant importance for sustainable development through its valorization. This study focuses on characterizing a manganese sludge and investigating its behavior during sulfuric acid leaching. The influence of process conditions, including temperature, acid concentration, liquid to solid ratio, and leaching duration, was examined. The results revealed that Mn, Zn, and K are the main leachable components, and their overall leaching rates increase with increasing temperature, liquid to solid ratio, and time. However, the acid concentration requires optimization. High leaching rates of 90% for Mn, 90% for Zn, and 100% for K were achieved. Moreover, it was found that Pb in the sludge is converted to sulfate during the leaching, which yields a sulfate concentrate rich in PbSO₄. The leaching process for Mn and Zn species appears to follow a second or third order reaction, and the calculation of rate constants indicated that Mn leaching kinetics are two to five times higher than those for Zn. Thermodynamic calculations were employed to evaluate the main chemical reactions occurring during leaching. Full article

(This article belongs to the Special Issue Sustainability, Circular Economy and Waste Recycling: Advances in Materials Research)

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20 pages, 6692 KiB

Open AccessArticle

Preliminary Study of Preheated Decarburized Activated Coal Gangue-Based Cemented Paste Backfill Material

by Renlong Tang, Bingchao Zhao, Chuang Tian, Baowa Xu, Longqing Li, Xiaoping Shao and Wuang Ren

Materials 2023, 16(6), 2354; https://doi.org/10.3390/ma16062354 - 15 Mar 2023

Cited by 3 | Viewed by 1658

Abstract

This study proposes a novel idea of the use of coal gangue (CG) activation and preheated decarburized activated coal CG-based cemented paste backfill material (PCCPB) to realize green mining. PCCPB was prepared with preheated decarburized coal CG (PCG), FA, activator, low-dose cement, and water. This idea realized scale disposal and resource utilization of coal CG solid waste. Decarbonization and activation of CG crushed the material to less than 8 mm by preheated combustion technology at a combustion temperature of 900 °C and a decarbonization activation time of 4 min. The mechanism of the effect of different Na₂SO₄ dosages on the performance of PCCPB was investigated using comprehensive tests (including mechanical property tests, microscopic tests, and leaching toxicity tests). The results show that the uniaxial compressive strength (UCS) of C-S2, C-S3, and C-S4 can meet the requirements of backfill mining, among which the UCS of C-S3 with a curing time of 3 d and 28 d were 0.545 MPa and 4.312 MPa, respectively. Na₂SO₄ excites PCCPB at different curing time, and the UCS of PCCPB increases and then decreases with the increase in Na₂SO₄ dosage, and 3% of Na₂SO₄ had the best excitation effect on the late strength (28 d) of PCCPB. All groups’ (control and CS1-CS4 groups) leachate heavy metal ions met the requirements of groundwater class III standard, and PCCPB had a positive effect on the stabilization/coagulation of heavy metal ions (Mn, Zn, As, Cd, Hg, Pb, Cr, Ba, Se, Mo, and Co). Finally, the microstructure of PCCPB was analyzed using FTIR, TG/DTG, XRD, and SEM. The research is of great significance to promote the resource utilization of coal CG residual carbon and realize the sustainable consumption of coal CG activation on a large scale. Full article

(This article belongs to the Special Issue Sustainability, Circular Economy and Waste Recycling: Advances in Materials Research)

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14 pages, 5220 KiB

Open AccessArticle

Study on the Effect of Temperature on the Crystal Transformation of Microporous Calcium Silicate Synthesized of Extraction Silicon Solution from Fly Ash

by Dong Kang, Zhijie Yang, De Zhang, Yang Jiao, Chenyang Fang and Kaiyue Wang

Materials 2023, 16(6), 2154; https://doi.org/10.3390/ma16062154 - 7 Mar 2023

Cited by 5 | Viewed by 1815

Abstract

In this study, microporous calcium silicate was synthesized from a silicon solution of fly ash extracted by soaking in strong alkali as a silicon source. By means of XRD, TEM, FTIR, and thermodynamic calculations, the crystal evolution and growth process of microporous calcium silicate were studied under the synthesis temperature of 295~365 K. The results show that calcium silicate is a single-chain structure of the Si–O tetrahedron: Q1 type Si–O tetrahedron is located at both ends of the chain, and the middle is the [SiO₄⁴⁻] tetrahedron connected by [O²⁻] coplanar, and Ca²⁺ is embedded in the interlayer structure of calcium silicate. The formation rate and crystallization degree of calcium silicate hydrate were positively correlated with temperature. When the synthesis temperature was 295 K, its particle size was about 8 μm, and when the synthesis temperature was 330 K, a large number of amorphous microporous calcium silicate with a particle size of about 14 μm will be generated. When the temperature was above 350 K, the average particle size was about 17 μm. The microporous calcium silicate showed obvious crystalline characteristics, which indicate that the crystallization degree and particle size of microporous calcium silicate could be controlled by a reasonable synthesis temperature adjustment. Full article

(This article belongs to the Special Issue Sustainability, Circular Economy and Waste Recycling: Advances in Materials Research)

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Review

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25 pages, 12311 KiB

Open AccessReview

Materials Enabling Methane and Toluene Gas Treatment

by Tong Lv and Rui Wang

Materials 2024, 17(2), 301; https://doi.org/10.3390/ma17020301 - 7 Jan 2024

Viewed by 1337

Abstract

This paper summarizes the latest research results on materials for the treatment of methane, an important greenhouse gas, and toluene, a volatile organic compound gas, as well as the utilization of these resources over the past two years. These materials include adsorption materials, catalytic oxidation materials, hydrogen-reforming catalytic materials and non-oxidative coupling catalytic materials for methane, and adsorption materials, catalytic oxidation materials, chemical cycle reforming catalytic materials, and degradation catalytic materials for toluene. This paper provides a comprehensive review of these research results from a general point of view and provides an outlook on the treatment of these two gases and materials for resource utilization. Full article

(This article belongs to the Special Issue Sustainability, Circular Economy and Waste Recycling: Advances in Materials Research)

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32 pages, 1718 KiB

Open AccessReview

Alternative to Conventional Solutions in the Development of Membranes and Hydrogen Evolution Electrocatalysts for Application in Proton Exchange Membrane Water Electrolysis: A Review

by Klara Perović, Silvia Morović, Ante Jukić and Krešimir Košutić

Materials 2023, 16(18), 6319; https://doi.org/10.3390/ma16186319 - 20 Sep 2023

Cited by 7 | Viewed by 3148

Abstract

Proton exchange membrane water electrolysis (PEMWE) represents promising technology for the generation of high-purity hydrogen using electricity generated from renewable energy sources (solar and wind). Currently, benchmark catalysts for hydrogen evolution reactions in PEMWE are highly dispersed carbon-supported Pt-based materials. In order for this technology to be used on a large scale and be market competitive, it is highly desirable to better understand its performance and reduce the production costs associated with the use of expensive noble metal cathodes. The development of non-noble metal cathodes poses a major challenge for scientists, as their electrocatalytic activity still does not exceed the performance of the benchmark carbon-supported Pt. Therefore, many published works deal with the use of platinum group materials, but in reduced quantities (below 0.5 mg cm⁻²). These Pd-, Ru-, and Rh-based electrodes are highly efficient in hydrogen production and have the potential for large-scale application. Nevertheless, great progress is needed in the field of water electrolysis to improve the activity and stability of the developed catalysts, especially in the context of industrial applications. Therefore, the aim of this review is to present all the process features related to the hydrogen evolution mechanism in water electrolysis, with a focus on PEMWE, and to provide an outlook on recently developed novel electrocatalysts that could be used as cathode materials in PEMWE in the future. Non-noble metal options consisting of transition metal sulfides, phosphides, and carbides, as well as alternatives with reduced noble metals content, will be presented in detail. In addition, the paper provides a brief overview of the application of PEMWE systems at the European level and related initiatives that promote green hydrogen production. Full article

(This article belongs to the Special Issue Sustainability, Circular Economy and Waste Recycling: Advances in Materials Research)

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32 pages, 2590 KiB

Open AccessEditor’s ChoiceReview

Microplastics Derived from Food Packaging Waste—Their Origin and Health Risks

by Kornelia Kadac-Czapska, Eliza Knez, Magdalena Gierszewska, Ewa Olewnik-Kruszkowska and Małgorzata Grembecka

Materials 2023, 16(2), 674; https://doi.org/10.3390/ma16020674 - 10 Jan 2023

Cited by 45 | Viewed by 8893

Abstract

Plastics are commonly used for packaging in the food industry. The most popular thermoplastic materials that have found such applications are polyethylene (PE), polypropylene (PP), poly(ethylene terephthalate) (PET), and polystyrene (PS). Unfortunately, most plastic packaging is disposable. As a consequence, significant amounts of waste are generated, entering the environment, and undergoing degradation processes. They can occur under the influence of mechanical forces, temperature, light, chemical, and biological factors. These factors can present synergistic or antagonistic effects. As a result of their action, microplastics are formed, which can undergo further fragmentation and decomposition into small-molecule compounds. During the degradation process, various additives used at the plastics’ processing stage can also be released. Both microplastics and additives can negatively affect human and animal health. Determination of the negative consequences of microplastics on the environment and health is not possible without knowing the course of degradation processes of packaging waste and their products. In this article, we present the sources of microplastics, the causes and places of their formation, the transport of such particles, the degradation of plastics most often used in the production of packaging for food storage, the factors affecting the said process, and its effects. Full article

(This article belongs to the Special Issue Sustainability, Circular Economy and Waste Recycling: Advances in Materials Research)

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