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Eco-Friendly Materials for Civil Construction: Utilization and Advantages

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A special issue of Sustainability (ISSN 2071-1050). This special issue belongs to the section "Sustainable Materials".

Deadline for manuscript submissions: closed (1 August 2022) | Viewed by 29163

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Special Issue Editors

Prof. Dr. Carlos Maurício Fontes Vieira

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Guest Editor

Advanced Materials Laboratory-LAMAV, State University of the Northern Rio de Janeiro-UENF, Campos dos Goytacazes, RJ, Brazil
Interests: foundry; bricks; porosity; ceramics; microstructure and solid waste
Special Issues, Collections and Topics in MDPI journals

Prof. Dr. Gustavo de Castro Xavier

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Guest Editor

Laboratory of Civil Engineering, State University of North Fluminense, Campos dos Goytacazes, RJ, Brazil
Interests: red ceramics; mortars; industrial wastes; natural fibers; Durability

Prof. Dr. Henry Alonso Colorado Lopera

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Guest Editor

Engineering School, Universidad de Antioquia, Medellin, Colombia
Interests: solid waste management; hazardous waste; ceramics; circular economy; natural fibers

Prof. Dr. Sergio Neves Monteiro

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Guest Editor

Materials Science Department – Military Institute of Engineering – IME, Rio de Janeiro, Brazil
Interests: less common latural fibers; thermorigid composites; mechanicla properties; fabric reinforced composites; fracture mechanics
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Planet Earth is becoming unsustainable for a society with a lifestyle that is increasingly consumerist and predatory to the environment. The linear economy has failed as a viable form of human development, as it entails a huge generation of waste and a negative impact on the environment. We currently consume poorly designed and energy-inefficient products that do not have adequate reuse, and therefore, the development of sustainable materials is mandatory as one of the pillars for the transition from a linear to a circular economy.

This Special Edition is dedicated to papers from academic researchers and industry innovators working on multidisciplinary experiments as well as modeling related to environmental sustainability. Papers are also welcome on economic and social aspects that would promote changes in the behavior that lead to disseminating the sustainable development of building constructions to preserve the environment. In particular, papers on construction materials used worldwide are encouraged aiming at improving efficiency, productivity, and competitiveness in world markets.

For this Special Issue, both scientific and technical papers are welcome aiming at our advanced understanding of ecofriendly building materials, which might promote savings in energy as well as pollutant reduction in the extraction of raw materials, manufacturing processes, or in final applications. These building materials can be more durable and also incorporated with urban, agricultural, or industrial wastes.

The main topics covered in this Special Issue include (but are not limited to):

Characterization, processing, and technological properties of ecofriendly building materials;
Analysis of the lifecycle of building materials;
Waste-incorporated building materials;
Recycling and circular economy of building materials;
- Heavy ceramics with industrial and agro-industrial residues;
- Mortar with industrial wastes;
- Mortar with natural fibers;
- Alkali-activated materials with industrial wastes;
- Composite with natural fibers and wastes;
- Artificial rocks with industrial waste;
- Cleaner steel manufacturing process.

Original studies and reviews on subjects other than the aforementioned that are deemed to contribute to an advance in the knowledge of ecofriendly building materials, their utilization, and advantages are welcome in this Special Issue.

AREA

Area of materials and technology: clay, heavy clay ceramics, mortars, alkali-activated materials, composites, natural and synthetic fibers, structural reinforcement, recycled materials, byproducts, and steel.

Prof. Dr. Carlos Maurício Fontes Vieira
Prof. Dr. Gustavo de Castro Xavier
Prof. Dr. Henry Alonso Colorado Lopera
Prof. Dr. Sergio Neves Monteiro
Guest Editors

Manuscript Submission Information

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. Sustainability is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

ecofriendly ceramics
life cycle analysis
agro-industrial and urban waste added building materials
circular economy
energy efficiency
recycling
mining and sustainability

Published Papers (13 papers)

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Research

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19 pages, 7617 KiB

Open AccessArticle

Structural Behavior of LC-GFRP Confined Waste Aggregate Concrete Square Columns with Sharp and Round Corners

by Rattapoohm Parichatprecha, Kittipoom Rodsin, Krisada Chaiyasarn, Nazam Ali, Songsak Suthasupradit, Qudeer Hussain and Kaffayatullah Khan

Sustainability 2022, 14(18), 11221; https://0-doi-org.brum.beds.ac.uk/10.3390/su141811221 - 07 Sep 2022

Cited by 1 | Viewed by 1069

Abstract

Reusing construction brick waste to fabricate new concrete is an economical and sustainable solution for the ever-increasing quantity of construction waste. However, the substandard mechanical properties of the concrete made using recycled crushed brick aggregates (RBAC) have limited its use mainly to non-structural applications. Several studies have shown that the axial compressive performance of the concrete is a function of the lateral confining pressure. Therefore, this study proposes to use low-cost glass fiber-reinforced polymer (LC-GFRP) wraps to improve the substandard compressive strength and ductility of RBAC. Thirty-two rectilinear RBAC specimens were constructed in this study and tested in two groups. The specimens in Group 1 were tested without the provision of a corner radius, whereas a corner radius of 26 mm was provided in the Group 2 specimens. Specimens in both groups demonstrated improved compressive behavior. However, the premature failure of LC-GFRP wraps near the sharp corners in Group 1 specimens undermined its efficacy. On the contrary, the stress concentrations were neutralized in almost all Group 2 specimens with a 26 mm corner radius, except low-strength specimen with six layers of LC-GFRP. As a result, Group 2 specimens demonstrated a more significant improvement in peak compressive strength and ultimate strain than Group 1 specimens. An analytical investigation was carried out to assess the efficiency of existing compressive stress–strain models to predict the peak compressive stress and ultimate of LC-GFRP-confined RBAC. Existing FRP models were found unreliable in predicting the key parameters in the stress–strain curves of LC-GFRP-confined RBAC. Equations were proposed by using nonlinear regression analysis, and the predicted values of the key parameters were found in good agreement with the corresponding experimental values. Full article

(This article belongs to the Special Issue Eco-Friendly Materials for Civil Construction: Utilization and Advantages)

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15 pages, 4866 KiB

Open AccessArticle

Application of Glass Waste on Red Ceramic to Improve Sintering

by Geovana Delaqua, Juan Magalhães, Markssuel Marvila, Fernando Vernilli, Jr., Sérgio Monteiro, Henry Colorado and Carlos Vieira

Sustainability 2022, 14(16), 10454; https://0-doi-org.brum.beds.ac.uk/10.3390/su141610454 - 22 Aug 2022

Cited by 4 | Viewed by 1572

Abstract

Given the current huge generation of solid waste worldwide, alternative and innovative methodologies for incorporating these materials should be encouraged elsewhere. In this context, the objective of this research is to evaluate the use of glass waste as a substitute for sand as raw material in ceramics. Formulations containing from 0% to 20% of glass waste were produced, thus replacing natural sand. Extruded and calcined specimens were produced at temperatures of 800, 900 and 1000 °C. The characterization results demonstrated the compatibility and their potential for the glass waste for improving the properties of ceramics. Results of density, water absorption and flexural strength improved when 20% of glass waste was added due to the porosity reduction, provided by the formation of a liquid phase and then by a sintering, promoted by the glass waste. This resulted in coherent properties with ceramic applications in the form of tiles and blocks, at a calcining temperature of 800 °C. On the contrary, results without glass did not reach the necessary parameters even at 1000 °C. In conclusion, the feasibility of using glass waste has been proven, which, in addition to improving the material’s properties, provides economy benefits for the ceramic industry, with the calcination process at milder temperatures. Full article

(This article belongs to the Special Issue Eco-Friendly Materials for Civil Construction: Utilization and Advantages)

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15 pages, 3549 KiB

Open AccessArticle

Engineered Stone Produced with Glass Packaging Waste, Quartz Powder, and Epoxy Resin

by Gabriela Nunes Sales Barreto, Elaine Aparecida Santos Carvalho, Vitor da Silva de Souza, Maria Luiza Pessanha Menezes Gomes, Afonso R. G. de Azevedo, Sérgio Neves Monteiro and Carlos Maurício Fontes Vieira

Sustainability 2022, 14(12), 7227; https://0-doi-org.brum.beds.ac.uk/10.3390/su14127227 - 13 Jun 2022

Cited by 10 | Viewed by 2231

Abstract

Engineered stone (ENS) is a type of artificial stone composed of stone wastes bonded together by a polymeric matrix. ENS presents a profitable alternative for solid waste management, since its production adds value to the waste by reusing it as raw material and reduces environmental waste disposal. The present work’s main goal is to produce an ENS based on quartz powder waste, glass packaging waste, and epoxy resin. The wastes were size-distributed by the fine sieving method. Then, the closest-packed granulometric mixture, as well as the minimum amount of resin that would fill the voids of these mixtures, was calculated. ENS plates were prepared with 15%wt (ENS-15) and 20%wt (ENS-20) epoxy resin by vibration, compression (10 tons for 20 min at 90 °C), and vacuum of 600 mmHg. The plates were sanded and cut for physical, chemical, and mechanical tests. Scanning electron microscopy analysis of fractured specimens was performed. ENS-15 presented 2.26 g/cm³ density, 0.1% water absorption, 0.21% apparent porosity, and 33.5 MPa bend strength and was resistant to several chemical and staining agents. The results classified ENS as a high-quality coating material, technically and economically viable, with properties similar to commercial artificial stones. Therefore, the development of ENS based on waste glass and quartz powder meets the concept of sustainable development, as this proposed novel material could be marketed as a building material and simultaneously minimize the amount of these wastes that are currently disposed of in landfills. Full article

(This article belongs to the Special Issue Eco-Friendly Materials for Civil Construction: Utilization and Advantages)

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18 pages, 4319 KiB

Open AccessArticle

Circular Economy of Construction and Demolition Waste: A Case Study of Colombia

by Henry A. Colorado, Andrea Muñoz and Sergio Neves Monteiro

Sustainability 2022, 14(12), 7225; https://0-doi-org.brum.beds.ac.uk/10.3390/su14127225 - 13 Jun 2022

Cited by 10 | Viewed by 2943

Abstract

This paper presents the results of research into construction and demolition (C&D) waste in Colombia. The data and analyses are shown in a local and Latin American context. As the situation in Colombia is quite similar to that in many developing countries worldwide, this research and its findings are potentially applicable to similar economies. Several factors were calculated and compared in order to evaluate which best fit the data from Colombia. We also included an experimental characterization and analysis of several key types of C&D waste from important infrastructure projects in Colombia, specifically by using the X-ray diffraction and scanning electron microscopy techniques. For the quantification of CDW, a calculation was performed based on the area and four factors of volume and density, followed by an econometric analysis of the detailed information using the Hodrick–Prescott filter, which revealed the CDW trends. Our results revealed that there are limitations regarding the availability of information and effective treatments for this waste, as well as shortcomings in education and other issues, not only for Colombia but also for other countries in Latin America. Full article

(This article belongs to the Special Issue Eco-Friendly Materials for Civil Construction: Utilization and Advantages)

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18 pages, 3011 KiB

Open AccessArticle

Comparison between Synthetic and Biodegradable Polymer Matrices on the Development of Quartzite Waste-Based Artificial Stone

by Carlos Paulino Agrizzi, Elaine Aparecida Santos Carvalho, Mônica Castoldi Borlini Gadioli, Gabriela Nunes Sales Barreto, Afonso R. G. de Azevedo, Sérgio Neves Monteiro and Carlos Maurício Fontes Vieira

Sustainability 2022, 14(11), 6388; https://0-doi-org.brum.beds.ac.uk/10.3390/su14116388 - 24 May 2022

Cited by 16 | Viewed by 2026

Abstract

The development of artificial stone from the agglutination of polymeric resin using industrial wastes can be a viable alternative from a technical, economic, and sustainable point of view. The main objective of the present work was to evaluate the physical, mechanical, and structural properties of artificial stones based on quartzite waste added into a synthetic, epoxy, or biodegradable polyurethane polymer matrix. Artificial stone plates were produced through the vacuum vibration and compression method, using 85 wt% of quartzite waste. The material was manufactured under the following conditions: 3 MPa compaction pressure and 90 and 80 °C curing temperature. The samples were characterized to evaluate physical and mechanical parameters and microstructure properties. As a result, the artificial stone plates developed obtained ≤0.16% water absorption, ≤0.38% porosity, and 26.96 and 10.7 MPa flexural strength (epoxy and polyurethane resin, respectively). A wear test established both artificial quartzite stone with epoxy resin (AS-EP) and vegetable polyurethane resin (AS-PU) high traffic materials. Hard body impact resistance classified AS-EP as a low height material and AS-PU as a very high height material. The petrographic slides analysis revealed that AS-EP has the best load distribution. We concluded the feasibility of manufacturing artificial stone, which would minimize the environmental impacts that would be caused by this waste disposal. We concluded that the production of artificial rock shows the potential and that it also helps to reduce environmental impacts. Full article

(This article belongs to the Special Issue Eco-Friendly Materials for Civil Construction: Utilization and Advantages)

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11 pages, 1641 KiB

Open AccessArticle

Development of Sustainable Artificial Stone Using Granite Waste and Biodegradable Polyurethane from Castor Oil

by Maria Luiza Pessanha Menezes Gomes, Elaine Aparecida Santos Carvalho, Gabriela Nunes Sales Barreto, Rubén Jesus Sánchez Rodriguez, Sérgio Neves Monteiro and Carlos Maurício Fontes Vieira

Sustainability 2022, 14(11), 6380; https://0-doi-org.brum.beds.ac.uk/10.3390/su14116380 - 24 May 2022

Cited by 9 | Viewed by 2468

Abstract

Brazil is one of the world’s major ornamental stone producers. As a consequence, ornamental stone wastes are generated on a large scale and are usually open air disposed. Thus, it is important to develop novel material reusing these accumulated wastes, aiming to minimize environmental impact. The development of artificial stones made with ornamental stone wastes agglomerated by a synthetic polymer represents an excellent alternative and, therefore, is currently the subject of several works. This work seeks to develop an innovative artificial stone containing 85%wt of granite waste and 15%wt of vegetable polyurethane from castor oil, a biodegradable resin, from a renewable source. The purpose is creating a sustainable material, technically viable to be applied as a civil construction coating. To manufacture the artificial stone plates, granite and polyurethane were mixed and transferred to a metallic mold subjected to vibration, vacuum and, later, hot compression. The artificial stone presented low water absorption (0.13%) and apparent porosity (0.31%) as well as a favorable 17.31 MPa bend strength. These results were confirmed through the excellent particles/matrix adhesion displayed in the micrographs, in addition to great chemical resistance. Full article

(This article belongs to the Special Issue Eco-Friendly Materials for Civil Construction: Utilization and Advantages)

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24 pages, 3005 KiB

Open AccessArticle

Ornamental Stone Processing Waste Incorporated in the Production of Mortars: Technological Influence and Environmental Performance Analysis

by Pamella Inácio Moreira, Josinaldo de Oliveira Dias, Gustavo de Castro Xavier, Carlos Maurício Vieira, Jonas Alexandre, Sergio Neves Monteiro, Rogério Pinto Ribeiro and Afonso Rangel Garcez de Azevedo

Sustainability 2022, 14(10), 5904; https://0-doi-org.brum.beds.ac.uk/10.3390/su14105904 - 13 May 2022

Cited by 7 | Viewed by 1747

Abstract

The technological performance and environmental advantages of replacing sand by ornamental stone processing waste (OSPW) in the production of mortars for civil construction were studied. Technological properties associated with the standard consistency index, squeeze flow and bulk densities as well as the determination of water retention and calorimetry analysis were evaluated in the mortars’ fresh state, whereas capillarity tests as well as mechanical resistance by flexural and compression tests were determined in the hardened state for mortars incorporated with 10, 30 and 60 wt.% of OSPW substituting sand. Three different types of Portland Cements were considered in the incorporated mortars production. For these mortars environmental analysis, their corresponding life cycle assessment results were compared to that of conventional waste-free (0% OSPW) control mortar. It was found that the OPSW incorporation acts as nucleation sites favoring a hydration process, which culminates after 28 days of curing in the formation of more stable phases identified as hydrated calcium silicates by X-ray diffraction (XRD) amorphous halo. It was also revealed that both flexural and compression improved resistance for the incorporated mortars after 28 curing days. In particular, the calorimetry and XRD results explained the better mechanical resistance (12 MPa) of the 30 wt.% OSPW incorporated mortar, hardened with Portland Cement V, compared not only to the control, but also to the other incorporated mortars. As for the environmental analysis, the replacement of sand by OSPW contributed to the reduction in associated impacts in the categories of land use (−5%); freshwater eutrophication (−9%); marine eutrophication (−6%) and global warming (−5%). Full article

(This article belongs to the Special Issue Eco-Friendly Materials for Civil Construction: Utilization and Advantages)

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16 pages, 3895 KiB

Open AccessArticle

Feasibility Analysis of Mortar Development with Ornamental Rock Waste for Coating Application by Mechanized Projection

by Ana Luiza Paes, Jonas Alexandre, Gustavo de Castro Xavier, Sérgio Neves Monteiro and Afonso Rangel Garcez de Azevedo

Sustainability 2022, 14(9), 5101; https://0-doi-org.brum.beds.ac.uk/10.3390/su14095101 - 23 Apr 2022

Cited by 6 | Viewed by 1491

Abstract

The industrial production of lime generates greenhouse gases, which contributes to increase the global warming. Therefore, the present study evaluated the feasibility of replacing lime by ornamental rock waste (ORW) as a by-product of the related stone industry, and developed a cost-effective mortars. These new low-costing mortars are intended as fresh fluid paste coatings to be applied on walls by the mechanized projection technique. The ornamental rock waste was collected from a marble and granite industry as ground stone. It was finely crushed before mixing with cement, sand, water and superplasticizer in amounts of 1.0% (R01), 1.2% (R02) and 1.3% (R03), to prepare the mortars, which had the mixture, cement: ORW: sand, 1:1:4 in wt.%. These novel mortars were characterized in both fresh, for well projection, and hardened state, to evaluate the properties after curing performance. The results showed that mortar R03, achieved the best results and did not present cracks in the hardened state. Its water retention was found above 30%. Both tensile strength of 0.312 MPa and compressive strength 7.88 MPa, which are above the corresponding minimum required by the standard for external coating. Water absorption by immersion of 19.37% and void content of 20.23% were close to the corresponding values for hydrated lime mortar. Dry shrinkage showed that the new R03 mortar reached more than 90% of their total retraction at 7 days of cure without sign of cracking. These findings revealed the R03/ornamental rock waste -based mortar applied by mechanized projection as a promising sustainable substitute for common lime-based mortar. Full article

(This article belongs to the Special Issue Eco-Friendly Materials for Civil Construction: Utilization and Advantages)

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13 pages, 3846 KiB

Open AccessArticle

Novel Sustainable Castor Oil-Based Polyurethane Biocomposites Reinforced with Piassava Fiber Powder Waste for High-Performance Coating Floor

by Juliana Peixoto Rufino Gazem de Carvalho, Noan Tonini Simonassi, Felipe Perissé Duarte Lopes, Sergio Neves Monteiro and Carlos Maurício Fontes Vieira

Sustainability 2022, 14(9), 5082; https://0-doi-org.brum.beds.ac.uk/10.3390/su14095082 - 23 Apr 2022

Cited by 6 | Viewed by 1741

Abstract

The search for new greener materials that contribute to a more sustainable world motivated the present study in which novel biocomposites with 10, 20 and 30 vol% of piassava fiber powder waste reinforcing castor oil-based polyurethane (COPU) intended for a high-performance coated floor (HPCF) were developed. The novel biocomposites were characterized by flexural, Izod impact and wear standard tests as well as Fourier transform infrared spectroscopy (FTIR) and fracture analysis using scanning electron microscopy (SEM). Both flexural modulus and strength displayed marked increases reaching more than 800 and 500%, respectively, compared to plain COPU for 30 vol% piassava powder incorporation. FTIR bands indicated the existence of interaction between the piassava constituents and COPU. However, SEM fractographs disclosed the presence of bubbles attributed to retained gases during the COPU curing. Consequently, the Izod impact resistance showed a 50% decrease while the wear was more than three times accentuated for 30 vol% piassava powder biocomposite. These results met the specified values of corresponding standards and revealed a promising new greener material for HPCFs. Full article

(This article belongs to the Special Issue Eco-Friendly Materials for Civil Construction: Utilization and Advantages)

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14 pages, 42663 KiB

Open AccessArticle

Composite Soil Made of Rubber Fibers from Waste Tires, Blended Sugar Cane Molasses, and Kaolin Clay

by Juan E. Jiménez, Carlos Mauricio Fontes Vieira and Henry A. Colorado

Sustainability 2022, 14(4), 2239; https://0-doi-org.brum.beds.ac.uk/10.3390/su14042239 - 16 Feb 2022

Cited by 7 | Viewed by 1778

Abstract

The use of different chemical and biological admixtures to improve the ground conditions has been a common practice in geotechnical engineering for decades. The use of waste material in these mixtures has received increasing attention in the recent years. This investigation evaluates the effects of using recycled tire polymer fibers (RTPF) and sugar molasses mixed with kaolin clay on the engineering properties of the soil. RTPF were obtained from a tire recycling company, while the molasses were extracted from a sugar cane manufacturer, both located in Colombia. RTPF is a waste and therefore its utilization is the first positive impact of this research, a green solution for this byproduct. Treated kaolin clay is widely used in many industrial processes, such as concrete, paper, paint, and traditional ceramics. The characterization was conducted with scanning electron microscopy, compression strength, particle-size distribution, x-ray diffraction, compressive and density tests. The results showed that the unconfined compressive strength improved from about 1.42 MPa for unstabilized samples, to 2.04 MPa for samples with 0.1 wt% of fibers, and 2.0 wt% molasses with respect to the dry weight of the soil. Furthermore, it was observed that soil microorganisms developed in some of the samples due to the organic nature of the molasses. Full article

(This article belongs to the Special Issue Eco-Friendly Materials for Civil Construction: Utilization and Advantages)

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12 pages, 2247 KiB

Open AccessCommunication

Ubim Fiber (Geonoma baculífera): A Less Known Brazilian Amazon Natural Fiber for Engineering Applications

by Belayne Zanini Marchi, Michelle Souza Oliveira, Wendell Bruno Almeida Bezerra, Talita Gama de Sousa, Verônica Scarpini Candido, Alisson Clay Rios da Silva and Sergio Neves Monteiro

Sustainability 2022, 14(1), 421; https://0-doi-org.brum.beds.ac.uk/10.3390/su14010421 - 31 Dec 2021

Cited by 10 | Viewed by 2137

Abstract

The production of synthetic materials generally uses non-renewable forms of energy, which are highly polluting. This is driving the search for natural materials that offer properties similar to synthetic ones. In particular, the use of natural lignocellulosic fibers (NLFs) has been investigated since the end of 20th century, and is emerging strongly as an alternative to replace synthetic components and reinforce composite materials for engineering applications. NLFs stand out in general as they are biodegradable, non-polluting, have comparatively less CO₂ emission and are more economically viable. Furthermore, they are lighter and cheaper than synthetic fibers, and are a possible replacement as composite reinforcement with similar mechanical properties. In the present work, a less known NLF from the Amazon region, the ubim fiber (Geonoma bacculifera), was for the first time physically characterized by X-ray diffraction (XRD). Fiber density was statistically analyzed by the Weibull method. Using both the geometric method and the Archimedes’ technique, it was found that ubim fiber has one of the lowest densities, 0.70–0.73 g/cm³, for NLFs already reported in the literature. Excluding the porosity, however, the absolute density measured by pycnometry was relatively higher. In addition, the crystallinity index, of 83%, microfibril angle, of 7.42–7.49°, and ubim fiber microstructure of lumen and channel pores were also characterized by scanning electron microscopy. These preliminary results indicate a promising application of ubim fiber as eco-friendly reinforcement of civil construction composite material. Full article

(This article belongs to the Special Issue Eco-Friendly Materials for Civil Construction: Utilization and Advantages)

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Review

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19 pages, 2178 KiB

Open AccessEditor’s ChoiceReview

Sustainability and Circular Economy Perspectives of Materials for Thermoelectric Modules

by Manuela Castañeda, Elkin I. Gutiérrez-Velásquez, Claudio E. Aguilar, Sergio Neves Monteiro, Andrés A. Amell and Henry A. Colorado

Sustainability 2022, 14(10), 5987; https://0-doi-org.brum.beds.ac.uk/10.3390/su14105987 - 15 May 2022

Cited by 9 | Viewed by 2966

Abstract

The growing demand for energy and the environmental problems derived from this problem are arousing interest throughout the world in the development of clean and efficient alternative energy sources, which involve ecological processes and materials. The materials used in the processes associated with thermoelectric generation technology will provide solutions to this situation. Materials related to energy make it possible to generate energy from waste heat residues, which are derived from various industrial processes in which significant fractions of residual energy are deposited into the environment. However, despite the fact that thermoelectric technology represents some relative advantages in relation to other energy generation processes, it in turn faces some technical limitations such as its low efficiency with respect to the high costs that its implementation demands today, and this has been the subject of intense research in recent years. On the other hand, the sustainability of the processes when analyzed from a circular economy perspective must be taken into account for the implementation of this technology, particularly when considering its large-scale implementation. In this article, a systematic search focused on the sustainability of thermoelectric modules is carried out as a step towards a circular economy model. The review aims to examine recent developments and trends in the development of thermoelectric systems in order to promote initiatives in favor of the environment. The aim of this study is to present a current overview, including trends and limitations, in research related to thermoelectric materials. As a result of this analysis, it was found that aspects related to costs and initiatives related to circular economy models have been little explored, which represents not only an opportunity for the development of new approaches in the conception of thermoelectric systems, but also for the conception of optimized designs that address the current limitations of this technology. Full article

(This article belongs to the Special Issue Eco-Friendly Materials for Civil Construction: Utilization and Advantages)

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17 pages, 2410 KiB

Open AccessReview

Environmental Impact and Sustainability of Calcium Aluminate Cements

by John F. Zapata, Afonso Azevedo, Carlos Fontes, Sergio Neves Monteiro and Henry A. Colorado

Sustainability 2022, 14(5), 2751; https://0-doi-org.brum.beds.ac.uk/10.3390/su14052751 - 26 Feb 2022

Cited by 17 | Viewed by 3873

Abstract

This investigation presents a critical analysis of calcium aluminate cements (CAC), specifically associated with sustainability and environmental impact, and the potential of these cements to help solve certain worldwide problems. Areas of research include cements as recycling holding materials, sustainability, circular economy, production costs, and energy. This investigation summarizes the current trends, perspectives, and the main concerns regarding CAC. Detailed information about the materials and processes involved in CAC is also presented. First, a general search was made using the Carrot2 Workbench metasearch engine to identify possible thematic groups correlated with CAC, then a more in-depth and specialized search was done using the Scopus database. The results revealed that these materials have a lot of potential to help solve problems in the circular economy and suggest several exciting areas for conducting future research. Full article

(This article belongs to the Special Issue Eco-Friendly Materials for Civil Construction: Utilization and Advantages)

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