Cleaner Materials最新文献

{"title":"Enhancing performance of recycled aggregate concrete with supplementary cementitious materials","authors":"Abba Fatiha ,&nbsp;Ezziane Karim ,&nbsp;Adjoudj Mhamed ,&nbsp;Abed Farid","doi":"10.1016/j.clema.2025.100298","DOIUrl":"10.1016/j.clema.2025.100298","url":null,"abstract":"<div><div>The substitution of natural coarse aggregates (NCA) by recycled coarse aggregates (RCA) is part of the environmental approach aimed at reducing waste and preserve natural resources. Unfortunately, RCA is of poor quality due to the presence of old mortar attached to its surface. It is characterized by its low density, high absorption, low rigidity and a poor quality interfacial transition zone (ITZ) which results in a lower quality concrete. This experimental study aims to introduce together with RCA aggregates supplementary cementitious materials (SCM) in order to reduce the decrease in mechanical performance, durability and microstructure of concrete. In a concrete based on RCA aggregates, ordinary cement was replaced with 20% natural pozzolan (NP), 10% limestone powder (LP), 20% ground granulated blast furnace slag (GGBFS) or 10% fumed silica (SF). Concrete was studied in terms of workability, superplasticizer requirements, mechanical strength, water absorption and microstructure. The results reveal that SCM significantly improves the performance of RAC concrete by promoting filling effects, nucleation, pozzolanic reactions and hydraulic activity. In the long term, RAC concrete has a 12% lower strength than OAC concrete. This decrease is reduced to only 3% when using LP and even results in 9% and 28% higher strengths when using GGBFS or SF. Similarly, an improvement in structural porosity up to 28% is observed, which led to a significant reduction in shrinkage strain, ranging from 20% to 44%.</div></div>","PeriodicalId":100254,"journal":{"name":"Cleaner Materials","volume":"15 ","pages":"Article 100298"},"PeriodicalIF":0.0,"publicationDate":"2025-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143208219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Selected residual biomass valorization into pellets as a circular economy-supported end-of-waste","authors":"Zane Vincevica-Gaile ,&nbsp;Maryna Zhylina ,&nbsp;Andrei Shishkin ,&nbsp;Linda Ansone-Bertina ,&nbsp;Linards Klavins ,&nbsp;Lauris Arbidans ,&nbsp;Linda Dobkevica ,&nbsp;Ivar Zekker ,&nbsp;Maris Klavins","doi":"10.1016/j.clema.2025.100295","DOIUrl":"10.1016/j.clema.2025.100295","url":null,"abstract":"<div><div>Among prospective directions to convert residual biomass into valuable products is pelleting, which can be followed by low-temperature pyrolysis, serving as an economically justified method for reducing the final waste stream. In this study, fresh and biochar pellets were obtained from selected residual biomass – waste derived from widespread industries such as energy production, food processing, and forestry and chemical processing in a mixture with peat processing residues used as a binder. Obtained pellets consisted of woody biomass ashes (ASP3 and ASP5) or coffee grounds (CSP3 and CSP5) at equal proportions mixed with spruce needles biomass (48.5 % or 47.5 %) by adding 3 % or 5 % of peat processing residues as a binder, respectively, as indicated. Biochar pellets were obtained by pyrolyzing fresh pellets at 500 °C with a heating rate of 5 °C/min. Chemical-physical properties (e.g., moisture content, ash content, chemical composition, porosity, density) of pellets were studied. The most promising for further use were assessed CSP3. In turn, ASP5 were characterized by relatively higher carbon framework density, surface area (6.889 <!--> <!-->m²/g), and water absorption (97.83 %), indicating their use as a sorbent applicable, e.g., for wastewater treatment, while others can be used in soil quality improvement and sustainable agriculture support. The conversion of residual biomass into fresh and biochar pellets serves as an efficient approach in end-of-waste following the targets of circular economy towards zero-waste production.</div></div>","PeriodicalId":100254,"journal":{"name":"Cleaner Materials","volume":"15 ","pages":"Article 100295"},"PeriodicalIF":0.0,"publicationDate":"2025-01-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of manufacturing variables on the mechanical performance of recycled glass-enhanced composites","authors":"Nathaphon Buddhacosa ,&nbsp;Thevega Thevakumar ,&nbsp;Everson Kandare ,&nbsp;Sujeeva Setunge ,&nbsp;Dilan Robert","doi":"10.1016/j.clema.2025.100297","DOIUrl":"10.1016/j.clema.2025.100297","url":null,"abstract":"<div><div>This study investigated the influence of various manufacturing conditions – including moulding pressure, post-curing, and aging – on the microstructure and mechanical properties (flexural and tensile) of epoxy matrix composites incorporating recovered glass particles at weight fractions ranging from 84 wt% to 90 wt%. The study focused on understanding how these conditions affect the interfacial bonding between the glass particles, epoxy matrix, and void content to establish a correlation between microstructure and mechanical performance before and after ceramification. The findings revealed that increasing moulding pressure from 1.1 MPa to 6.6 MPa reduced void content, increased composite density, and significantly improved flexural properties. The impact of post-curing on the composites’ flexural performance was also examined, and it was found that adjusting the epoxy matrix weight fraction from 6 wt% to 12 wt% further influenced the composite’s mechanical properties. X-ray computed tomography (CT) and scanning electron microscopy (SEM) analyses revealed changes in composite porosity and interfacial bonding, enabling the correlation of these microstructural changes with variations in mechanical properties for both non-ceramified and ceramified composites. Ceramification induced additional microstructural changes, including the formation of voids, which influenced the composites’ mechanical properties. Additionally, the effect of integrating steel wire mesh with 6.5 mm apertures on the mechanical performance of the glass/epoxy composites, both before and after ceramification, was explored.</div></div>","PeriodicalId":100254,"journal":{"name":"Cleaner Materials","volume":"15 ","pages":"Article 100297"},"PeriodicalIF":0.0,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Carbonation reaction of recycled concrete aggregates (RCA): CO2 mass consumption under various treatment conditions","authors":"Hossein Sousanabadi Farahani ,&nbsp;Amin Hosseini Zadeh ,&nbsp;Jiong Hu ,&nbsp;Chris Hawkins ,&nbsp;Seunghee Kim","doi":"10.1016/j.clema.2025.100296","DOIUrl":"10.1016/j.clema.2025.100296","url":null,"abstract":"<div><div>Concrete is a key building material around the world due to its excellent strength and durability. Recycling demolished concrete for new construction materials may play a significant role in sustainable development. Producing recycled concrete aggregates (RCA) from waste concrete is one approach for such an initiative. However, using RCA may pose challenges, such as reduced density, lower elastic modulus and strength, and increased water absorption. Recently, the carbonation of RCA has emerged as a method to address those concerns. This study explores the carbon sequestration capacity of RCA through carbonation, examining various parametric conditions, including initial CO₂ pressure, relative humidity, temperature, and pre-treatment approach. Both lab-scale and large-scale carbonation tests were conducted. Additionally, a cost analysis and CO₂ footprint assessment were performed. The findings showed that applying higher initial CO₂ pressures (<em>e.g.</em>, 40–60 psi) and optimal relative humidity (∼55 %) could significantly enhance the carbonation efficiency of RCA. Elevating temperature also led to accelerated CO₂ consumption, being more effective on the lab scale. The economic analysis presented potential cost benefits when substituting natural aggregates with CO₂-treated RCA. All in all, these results suggest that the carbonation of RCA may provide significant environmental benefits through carbon sequestration, promoting sustainable construction practices.</div></div>","PeriodicalId":100254,"journal":{"name":"Cleaner Materials","volume":"15 ","pages":"Article 100296"},"PeriodicalIF":0.0,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Self-cleaning stone Façades using TiO2 Microwave-Synthesised Coatings","authors":"David Henriques Bento ,&nbsp;Maria Leonor Matias ,&nbsp;Maria Magalhães ,&nbsp;Catarina Quitério ,&nbsp;Ana Pimentel ,&nbsp;Dora Sousa ,&nbsp;Pedro Amaral ,&nbsp;Carlos Galhano ,&nbsp;Elvira Fortunato ,&nbsp;Rodrigo Martins ,&nbsp;Daniela Nunes","doi":"10.1016/j.clema.2025.100294","DOIUrl":"10.1016/j.clema.2025.100294","url":null,"abstract":"<div><div>This study explores the development and characterization of self-cleaning coatings using titanium dioxide (TiO₂) nanoparticles for natural stone façades, particularly limestone. An energy-efficient, eco-friendly, fast (30 min), and low temperature (110 °C) microwave-assisted solvothermal method is reported for synthesising TiO₂ nanoparticles. These nanoparticles were integrated into coatings that were further applied to limestone substrates via spray-coating, maintaining the stone’s appearance while enhancing its self-cleaning properties. Characterization techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM), energy-dispersive X-ray spectroscopy (EDX), UV–VIS spectroscopy and Brunauer-Emmett-Teller (BET) surface area analysis were used to fully characterize the nanopowder. The anatase phase of TiO₂ nanoparticles and a band gap energy of about 3.24 eV were confirmed. SEM and STEM observations revealed that the nanopowder is formed by spherical particles with very fine nanocrystals highly agglomerated, however ensuing a high specific surface area of 199 m²/g. The self-cleaning properties of the coated limestone were assessed using static contact angle measurements. The results showed a significant enhancement in hydrophilicity, with the static contact angle of the coated limestone substrate reducing to nearly zero even without UV exposure, indicating complete wettability. The coating was also subjected to adhesion tests, confirming the presence of TiO₂ nanoparticles even after multiple cycles. The photocatalytic activity of the developed coating was evaluated using rhodamine B and methyl orange as model pollutants under solar radiation. The coating effectively degraded both model pollutants, and the photocatalytic cycling tests revealed a stable performance after multiple cycles. This research provides a promising approach for creating sustainable and low-maintenance building materials, contributing to preserving natural stone façades and reducing environmental impact in the construction industry.</div></div>","PeriodicalId":100254,"journal":{"name":"Cleaner Materials","volume":"15 ","pages":"Article 100294"},"PeriodicalIF":0.0,"publicationDate":"2025-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fiber-reinforced geopolymers made with recycled aggregates for screed flooring and repair applications","authors":"Joud Hwalla ,&nbsp;Hilal El-Hassan ,&nbsp;Joseph J. Assaad ,&nbsp;Tamer El-Maaddawy","doi":"10.1016/j.clema.2025.100293","DOIUrl":"10.1016/j.clema.2025.100293","url":null,"abstract":"<div><div>The increase in greenhouse gas emissions from cement production, along with limited landfill capacity for construction waste, has driven research into finding sustainable alternatives to replace cement and natural aggregates. While cement replacement with geopolymeric binders in mortar and concrete has been proven feasible, replacing natural aggregates with recycled counterparts has led to performance losses. To offset this drawback, different additives, including fibers, have been incorporated into such construction materials. This study evaluates the feasibility of using steel fiber (SF)-reinforced geopolymer (GP) composites incorporating recycled fine aggregates (RFA) for screed flooring and repair applications. GP mixes were prepared with RFA mass substitution up to 100 %, alongside SF volume of 0.5 % and 1 %. Flow values of 125 ± 25 mm were attained within 35 to 70 min. The 7-day compressive strength of GP composites reached 74.0 % to 96.2 % of their 28-day values. RFA substitution reduced compressive strength, elastic modulus, tensile strength, pull-off bond strength, and energy absorption and increased impact indentation and abrasion mass loss by up to 56, 69, 60, 23, 68, 266, and 2025 %, respectively. Conversely, SF addition improved most of these properties except for compressive and pull-off bond strength, which slightly decreased. GP composites made with 0 %, 25 %, and 50 % RFA satisfied the strength requirements for use in structural repair, while those with higher RFA replacement were suitable for non-structural use. Based on BS 8204, GP mixes were categorized as Category A screed flooring except the plain mix made with 100 % RFA, which was categorized as Category B.</div></div>","PeriodicalId":100254,"journal":{"name":"Cleaner Materials","volume":"15 ","pages":"Article 100293"},"PeriodicalIF":0.0,"publicationDate":"2025-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Concrete carbon mixing – A systematic review on the processes and their effects on the material performance","authors":"Marco Davolio,&nbsp;Giovanni Muciaccia,&nbsp;Liberato Ferrara","doi":"10.1016/j.clema.2025.100292","DOIUrl":"10.1016/j.clema.2025.100292","url":null,"abstract":"<div><div>The need for concrete industry to meet the climate neutrality target raised the attention towards carbon capture and utilization (CCU) technologies. Among the various solutions, cementitious materials can benefit from enforced carbonation, a thermodynamically stable reaction that permanently sequesters carbon dioxide into cement compounds. A possible enforced carbonation process is concrete carbon mixing, which involves the addition of pumping systems into concrete production lines to inject carbon dioxide into the material while in a fresh state. Various studies attempted to improve the efficiency of the process and to increase the quantity of fixed carbon dioxide. The current literature was systematically analysed to provide an overview of process parameters, possible injection systems, and properties of carbonated cementitious products. The studies were classified according to the injection stage: carbonation of the mixing water, carbonation of the cement slurry, or injection during concrete mixing with all the components. Concrete carbon mixing has proven to be promising for carbon dioxide sequestration through enforced carbonation, as the injection process enhanced the properties of the final product in most instances. In addition, other relevant aspects of carbon dioxide sequestration processes were discussed. Firstly, the methods and formulations to determine the CO₂ uptake were presented together with cross-comparison studies. Moreover, the methodological aspects of life cycle assessment (LCA) applied to concrete carbon mixing processes were discussed, showing the lack of systematic studies. In conclusion, simplified evaluations demonstrated the economic viability of carbon dioxide injection in fresh concrete, supporting future industrial deployment and discussing the challenges for the upscaling.</div></div>","PeriodicalId":100254,"journal":{"name":"Cleaner Materials","volume":"15 ","pages":"Article 100292"},"PeriodicalIF":0.0,"publicationDate":"2025-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing double-layer rubber composites for eco-friendly laminates: A thermal-mechanical characterization","authors":"Thanwit Naemsai ,&nbsp;Chatree Homkhiew ,&nbsp;Theerawat Petdee ,&nbsp;Chainarong Srivabut","doi":"10.1016/j.clema.2024.100290","DOIUrl":"10.1016/j.clema.2024.100290","url":null,"abstract":"<div><div>This study investigated the optimal design of double-layer rubber composites for eco-friendly laminates. A comprehensive methodology was used, combining material selection, manufacturing processes, and structural optimization to create composites with improved conductivity, strength, durability, and environmental sustainability. The Box-Behnken design methodology was utilized to optimize the formulation of these composites, yielding an optimal solution characterized by a desirability score of 0.714. This optimal formulation consists of a blowing agent content of 12 parts per hundred rubber (phr), wood sawdust content of 80 phr, and a processing temperature of 110 °C. The projected performance characteristics for this optimal composite formulation include a thermal conductivity of 0.023 watts per meter-kelvin (W/mK), a peeling force of 0.728 kN, a puncture force of 97.84 N, and a shearing force of 0.344 kN. Furthermore, an analysis of dimensionless parameters identified a favorable thickness ratio of 0.5 for the double-layer laminate wall panels, which corresponds to a total thickness of 10 mm. This finding is consistent with the principles of green building, facilitating resource efficiency. By adopting a holistic design approach, this study demonstrates a viable strategy for developing high-performance and sustainable double-layer rubber composites tailored for eco-friendly laminates, thus contributing to advancements in green building solutions.</div></div>","PeriodicalId":100254,"journal":{"name":"Cleaner Materials","volume":"15 ","pages":"Article 100290"},"PeriodicalIF":0.0,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Waste plastic management: Recycling and the environmental health nexus","authors":"Sodiq Adeyeye Nafiu ,&nbsp;Musa O. Azeez ,&nbsp;Khaled M. AlAqad ,&nbsp;Taofiq Abdulraheem Olarewaju ,&nbsp;Emmanuel Amuntse Yerima ,&nbsp;Abdulkadir Tanimu","doi":"10.1016/j.clema.2024.100291","DOIUrl":"10.1016/j.clema.2024.100291","url":null,"abstract":"<div><div>The increasing production of plastic materials and their subsequent disposal as waste have necessitated the development of effective waste management strategies. Among various approaches, the recycling of plastic waste has gained significant attention as an environmentally friendly alternative to landfilling and incineration. This manuscript explores the different methods of plastic recycling and their associated environmental and health impacts. Despite its economic advantages, mechanical recycling poses environmental and health risks, particularly due to the release of microplastics. These microplastics can contaminate the environment and enter the<!--> <!-->human body through inhalation and ingestion, leading to potential health hazards. Thus, strategies for mitigating microplastic pollution, including advanced sorting technologies and the implementation of IoT and RFID systems for efficient waste management were discussed. Furthermore, the environmental impacts of chemical recycling processes, especially concerning toxic chemical additives and greenhouse gas emissions, are examined. The findings highlight the need for improved waste management practices and the adoption of mitigation measures to reduce the environmental footprint of plastic waste recycling and promote public health.</div></div>","PeriodicalId":100254,"journal":{"name":"Cleaner Materials","volume":"15 ","pages":"Article 100291"},"PeriodicalIF":0.0,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recycling of mine tailings as supplementary cementitious material: Impact of mine tailings’ mineralogy on hydration behaviour and phase assemblage of Ordinary Portland cement blends","authors":"Godfrey Mawire ,&nbsp;Robbie McDonald ,&nbsp;Peter Austin ,&nbsp;Abhijit Mukherjee ,&nbsp;Lionel Esteban ,&nbsp;Navdeep K Dhami","doi":"10.1016/j.clema.2024.100288","DOIUrl":"10.1016/j.clema.2024.100288","url":null,"abstract":"<div><div>This study investigated the influence of mineral tailings’ mineralogy on hydration behaviour and phase assemblage of cured cement in ternary blends comprising Ordinary Portland cement (OPC), blast furnace slag (BFS) and tailings. The identification and quantification of mineral phases was achieved through Quantitative X-ray diffraction (QXRD) analysis, while the evaluation of mineral thermal stability was conducted using thermogravimetric analysis with mass spectrometry (TGA-MS). Isothermal calorimetry revealed that the tailings influenced the OPC heat flow profile during early-stage hydration, with minerals like dehydroxylated Fe-chlorite and alunite hydraulic properties contributing to the early-stage reaction mechanism. The bulk slow-reacting minerals in the tailings affected both the phase assemblage and the hydration mechanism of OPC by releasing elemental species that could be incorporated in the C-S-H phases. The chemical composition of the C-S-H formed in the blended cement varied and had a low Ca/Si ratio &lt; 1.3, enabling guest elements to be incorporated. Correlative Electron Microscopy Automated Mineralogy (CEM-AM) was utilised to analyse and map the distribution of the secondary C-S-H phases within the paste matrix. The findings give insight into the nature of hydrates formed in a ternary blend with tailings, which directly affect the cured cement’s performance and service life properties.</div></div>","PeriodicalId":100254,"journal":{"name":"Cleaner Materials","volume":"15 ","pages":"Article 100288"},"PeriodicalIF":0.0,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133206","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}