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Item Biomass-based wood composite for building material application(Cambridge Scholars Publishing, 2024) Mphahlele, IJ; Khoaele, Katleho K; Gbadeyan, O J; Chunilall, VirenFossil fuel serves as the primary global source of energy. It is anticipated that fossil fuels will be depleted in the next half-century. Using biomassbased wood composite for building applications serves as a substitute for fossil fuels. Biomass-based wood composite has proved to display good properties for application in the building sector. This chapter illustrates the valorization of biomass-based materials, sawdust, and wood flour in various building applications. Sawdust-based polymer resin polystyrene for particle board production displayed excellent compressive and tensile strengths of 0.157 N/mm2 and 2.362 N/mm2 respectively. Furthermore, cement substituted with sawdust exhibited satisfactory results for producing bricks or blocks. The results displayed a compressive strength of 10.43 N/mm² following ASTM C67. Moreover, clay bricks production using sawdust content of 2.5 wt% fired at 1100°C depicted a high compressive strength of 18.2 MPa, following ASTM C62-13a, which required a compressive strength of 17.2 MPa -according to the American National Standard Institute (ANSI), composites panels produced using sawdust with plastic waste and polystyrene exhibited good mechanical properties which can be applied for flooring application. The results displayed a modulus of elasticity (MOE) from 694.88 MPa to 4604.89 MPa and a modulus of rupture (MOR) from 5.73 to 21.24 MPa. Wood flour (WF) also displayed potential use in furniture applications. The results showed that 30 wt% WF-filled r-PP content wood polymer composite (WPC) displayed 24.8 MPa tensile strength. Moreover, the flexural strength of 46.2 MPa was achieved due to using MAPP as a coupling agent. According to the ASTM D 6662, the lowest flexural modulus of 0.34 GPa and 6.9 MPa flexural strength is required for decking boards. The results displayed excellent flexural modulus ranging from 2.49 to 3.8 GPa and flexural strength from 23.05 to 35.82 MPa. This is further evidence that wood flour-based composite can be utilized in decking application.Item Processing and characterization of biomass-based wood composites(Cambridge Scholars Publishing, 2024-10) Sekoai, Patrick T; Sithole, B; Olagunju, Olusegun A; Chunilall, VirenWood composites are gaining increased attention as sustainable alternatives to traditional building materials. This chapter explores the processing and characterization of biomass-based wood composites. We discuss various methods of processing biomass materials, including particle preparation, resin formulation, and composite manufacturing techniques. Additionally, we delve into the characterization techniques used to evaluate these composites' physical, mechanical, and thermal properties. The chapter aims to provide insights into the production and evaluation of biomassbased wood composites, highlighting their potential for a wide range of applications.Item 2D MXenes nanomaterials for removal of organic wastewater contaminants(CRC Press, 2024-12) Mdlalose, Lindani M; Hlekelele, Lerato; Chauke, Vongaini PThe research and development of two-dimensional (2D) materials was prompted and advanced after the discovery of the remarkable physical properties of single/multiple layered graphene. This hastily encouraged more research on 2D materials in the form of manipulating the structure of graphene through exfoliation, altering the starting material with readily available layered precursors such as graphite-like hexagonal boron nitride or dichalcogenides or even layered oxides [1]. This then stimulated the development of more 2D materials including the birth of MXenes. MXenes are a group 2D transition metal carbides, carbonitrides, and nitrides discovered in 2011 [2]. Their single flakes are denoted by a chemical formula Mn+1 Xn Tx (n = 1 to 4), which designates transition metals alternating layers (M) enclosed by carbon/nitrogen (X) layers with attached terminations Tx (-O2 , -F2 , -OH2 , -Cl2 ) on the external transition metal surfaces [3]. Due to their intriguing electrical and optical properties, they play numerous roles in photodetectors. Additionally, their distinctive mechanical, chemical, and physical properties allow MXenes to be altered by various surface terminations and transition metals. The atomically narrow structure of 2D MXenes makes it an appropriate alternative material for water purification technologies. Additionally, its large surface area, excellent mechanical strength, and numerous functional groups on their surfaces make it a suitable candidate for the uptake of contaminants from aqueous medium [4]. MXenes water purification interest is facilitated by its unique adsorptive, antibacterial, and reductive properties, which are further augmented by high electrical conductivity. With the intensive industrialization and vast agricultural systems, the release of toxic contaminants into ground and surface water continues to be a strain on the environment. In this chapter, the potential use of 2D MXenes derivatives for organic contaminants (such as dyes, antibiotics, and pharmaceuticals) removal is addressed. This entails mechanistic pathways of using MXene-based materials as adsorbents, water purification membranes, and photocatalysts. The ability of MXenebased composites in showing catalytic activity toward diverse pollutants and superior selectivity toward specific pollutants will be discussed.Item Phytic acid: A novel phosphate bio-Based flame retardant(Springer Nature, 2024-11) Sikhosana, ST; Mochane, MJ; Malebo, NJ; Mokhena, TC; Mofokeng, Tladi G; Sadiku, ER; Mokhena, TC; Mochane, MJ; Sadiku, ER; Ray, SSThe development and application of sustainable flame-retardant agents have become a research hotspot due to the urgent need for eco-friendly materials and the demand for a sustainable environmental protection. Phytic acid has gained popularity as a natural substance that is present in plant seeds with the potential to be a bio-based flame retardant. Its distinct structure, which consists of six phosphate groups, connected to a myoinositol core, confers inherent flame retardancy, making it a suitable candidate for fire safety in polymeric materials. Phytic acid can be added to polymer matrices through physical mixing, chemical grafting, or covalent bonding. This alters the thermal and mechanical properties of the resulting flame-retardant composite, as well as its fire performance. Ongoing research aims to maximize the potential of phytic acid in different polymeric systems, with the goal of creating safe, eco-friendly, and sustainable materials for fire safety applications in fields, such as: construction, automotive, electronics, and textiles.Item Durable PLA Bioplastics(Elsevier, 2024) Sinha Roy, Jayita; Ray, Suprakas SBioplastics are special plastics manufactured from biobased polymers and can potentially contribute to the circular plastics economy. In this direction, polylactic acid or polylactide (both abbreviated as PLA) is the most important commercially available polymer whose monomeric unit, lactic acid, can be produced from renewable resources. PLA has good thermal plasticity and mechanical properties and can be readily molded. During the manufacturing of PLA-based plastic products, the carbon footprint is approximately 75% lower than that of conventional plastic products. In the context of life cycle assessment and the eco-profile (input and output from the manufacturing process) of PLA, benefits and drawbacks, strategies for overcoming the drawbacks, and the trend of applications, it is worthy to develop PLA-based durable products considering regenerative technical approach. Therefore, this chapter reports recent progress in developing durable PLA bioplastics for various applications. Various strategies have been critically summarized, such as plasticization, copolymerization, and melt blending with different tough polymers, rubbers, thermoplastic elastomers, and nanomaterials. Changing the processing technology, modification of PLA by chemical methods or cross-linking and grafting, and annealing can improve the properties of PLA, which are also discussed in this chapter.Item Government initiatives in advancing the circular bioeconomy in South Africa(Cambridge Scholars Publishing, 2024-10) Sekoai, Patrick T; Sebogodi, Keolebogile R; Johakimu, Jonas K; Chunilall, Viren; Gbadeyan, OJ; Sekoai, P; Chunilall, VThe concept of a circular economy is receiving widespread attention among various stakeholders in South Africa as this scientific approach allows the management of waste streams in a sustainable and environmentally conscious manner while creating new value chains through the synthesis of high-value-added products such as fuels, chemicals, additives, etc. As opposed to the linear model that embraces the take, produce, and discard approach, the circular model embraces the recycle, reuse, and reduce approach, which involves the circularity of the wastes, leading to minimum and/or zero waste during the downstream process. Despite the various socioeconomic benefits that can be achieved from the circular biobased processes, various bottlenecks must be addressed before their full implementation. This chapter discusses the government initiatives to advance circular biobased opportunities in South Africa. The limitations that delay the progress of this technology are also discussed. The study also provides suggestions that could help fast-track the scalability of circular biobased technologies in South Africa.Item Green fabrication techniques for transparent wood composites: Pioneering sustainable materials for the future(Cambridge Scholars Publishing, 2024) Simelane, NP; Olatunji, OS; Mathew, Maya J; Andrew, Jerome EAs the world battles with environmental challenges and the need for sustainable alternatives to conventional building materials such as glass, transparent wood composites have emerged as a promising solution. Transparent wood composites, derived from renewable and abundant wood resources, offer a unique combination of strength, thermal insulation, and optical transparency. This chapter explores the latest progress in transparent wood composites, focusing on innovative and eco-friendly fabrication techniques that pave the way for widespread adoption in various applications. It highlights using sustainable wood sources, such as fast-growing trees, and reducing energy-intensive processing steps. The chapter also explores other emerging technologies, including nanocellulose reinforcements and bio-based polymers, that have the potential to revolutionize the fabrication of transparent wood composites. Through a comprehensive review of recent advancements and prospects, this chapter aims to provide researchers with valuable insights into the exciting world of transparent wood composites. Focusing on green fabrication techniques underscores the critical role transparent wood composites can play in building a more sustainable and environmentally responsible future.Item Fundamentals of biomass waste valorization(Cambridge Scholars Publishing, 2024-10) Khoaele, Katleho K; Gbadeyan, Oluwatoyin J; Mphahlele, IJ; Sithole, BB; Chunilall, Viren; Sekoai, P; Chunilall, V; Gbadeyan, JGThe devastating impact of climate change and the necessity for sustainable products and processing approaches are significant concerns for the worldwide population. Interestingly, there is an abundance of biomass resources, which might meet the increasing demand for green products, as using fossil fuels is no longer recommended due to environmental concerns and sustainability. Biomass resources (renewable feedstock for renewable energy generation and specialty chemicals) are sourced from several natural sources and have a variety of applications. Most developed economies follow linear consumption concepts that are not feasible in the long term. The circular bioeconomy concept is a promising solution to minimize waste landfilling, generate revenue, and maximize zero-waste by utilizing biomass waste. The valorization of cellulose, lignin, and hemicellulose fractions into bioproducts, biofuels, or specialty chemicals depends on the practicality of their pre-treatment and further processing approaches. This chapter discusses biomass feedstock history, valorization processes, and applications, and motivations for their exploration. Several value-added products, which can be harnessed from biomass and residues, are detailed.Item Air quality and health(Health Systems Trust, 2024-02) John, Juanette; Perumal, Sarisha; Mlambo, Mfundo; Naidoo, Mogesh; Ndlovu, Noluthando; Padarath, AshnieExposure to polluted air causes millions of premature deaths each year and can lead to health risks such as reduced lung growth and function, respiratory infections and aggravated asthma. Many deaths related to air pollution occur in Asia and Africa and poor air quality places an additional burden on the health.Item Emerging adaptation constrains in Mount Darwin District, Zimbabwe(Springer Nature, 2024-12) Chenzi, V; Mateyisi, Mohau J; Nangombe, SS; Maoela, MAThis chapter utilizes Mount Darwin district located in northern Zimbabwe’s Mashonaland Central province to examine climate change adaptation constrains in rural Southern Africa. The district is one of the worst affected regions by climate change in Zimbabwe. In order to shed greater light on climate change adaptation constrains in communal areas of Zimbabwe, the chapter canvassed a number of pertinent variables. These include, climate change-induced vulnerabilities, adaptation needs for catalytic economic sectors, livelihoods and food systems, adaptation responses and associated capital distribution in the context of the United Nations (UN) green development agenda, and domestication of adaptation solutions to meet Southern Africa’s needs. Findings from the study indicated that climate change vulnerabilities on rural livelihoods especially agriculture-based activities were influencing a shift towards artisanal mining as an alternative sustenance activity. Furthermore, there seems to be a symbiotic relationship between climate change patterns and livelihood activities in communal Zimbabwe. That is, climate change is not only influencing changes in rural livelihood activities, but the livelihood patterns are also responsible for intensifying the effects of climate change in the region. The study concluded by identifying several climate change adaptation measures in rural Southern Africa.Item Glass fibres - Production, structure, and applications(Elsevier, 2024) Orasugh, Jonathan T; Roy, S; Ray, Suprakas S; Chattopadhyay, D; Mondal, Md. IHOne of the most adaptable industrial materials available today is “glass fibres (GFs)”: they are easily made from raw infinitely abundant ingredients. Glass fibre made of silica has a long history. Common glass fibres are available in a variety of chemical compositions. The majority of glass fibres are silica-based (50–60% SiO2) and include a variety of additional oxides, including those of calcium, boron, sodium, aluminum, iron, and others. The letters E and C stand for electrical, corrosion/chemical, and high silica content, respectively. S denotes high silica content: S-glass can endure higher temperatures compared to its counterparts in addition to being a great electrical insulator, excellent strength, and a reasonable Young's modulus. Glass fibres are utilized to create printed circuit boards, structural composites, etc. This chapter discusses briefly, glass fibres history, its production, structure, applications, challenges, and ways forwards and then a concise conclusion is drawn.Item Fiber and textile waste valorization - towards environmental waste reduction(Cambridge Scholars Publishing, 2024-10) Baloyi, Rivalani B; Gbadeyan, OJ; Sithole, Bruce B; Chunilall, Viren; Gbadeyan, Oluwatoyin J; Sekoai, Patrick; Chunilall, VirenThe valorization of natural fibers and textile waste represents a promising approach to reducing environmental waste. This strategy involves converting waste materials into valuable products, promoting sustainability and resource efficiency. This chapter examines the technical feasibility of various textile recycling processes and assesses the challenges and limitations associated with each. A comprehensive analysis of various methodologies employed in the recycling and regeneration of fibers, extraction of cellulose, fermentation to bioethanol, pyrolysis, and conversion to other value-added products is discussed in detail. Additionally, the chapter offers insights into prospects and recommendations for establishing a sustainable economy for recycling textiles. The primary obstacles encountered in valorizing fibers and textiles encompass the substantial expenses associated with implementing valorization technologies, sorting and separation methodologies, and the limited yields attained during the processes. Consequently, a hierarchical strategy has been determined as the most effective approach for allocating each type of textile waste to the optimal valorization method, thereby facilitating the efficient retrieval of the preserved quality within the waste materials.Item Collagen-Based Hybrid Piezoelectric Material(John Wiley & Sons, Inc, 2024-04) Ghosh, A; Ray, Suprakas S; Orasugh, Jonathan T; Chattopadhyay, D; Ul-Islam, S; Wazed Ali, S; Bairagi, SPiezoelectricity, a bidirectional electromechanical coupling, has an extensive range of functions, such as energy harvesters, biomedical devices, sensors, cars, etc. A considerable amount of research has been conducted to investigate this phenomenon's energy harvesting potential. Traditional piezoelectric inorganics have high piezoelectric outputs but are frequently brittle and inflexible and may contain dangerous substances such as mercury or other heavy metals which are toxic to humans as well as other animals. Biological piezoelectric materials, on the other hand, are biodegradable, biocompatible, bioabsorbable, sustainable, non-cytotoxic, as well as facile to fabricate. As a result, they are valuable for a large number of applications, including tissue engineering, biological research, and energy harvesting. The rationale of this chapter is to describe the basis of piezoelectricity in collagen-based biological as well as non-biological hybrid materials, as well as the research involved in those materials as per literature, along with their uses and limitations.Item Valorization of food waste to high value-added products - An innovative approach toward a circular bioeconomy framework(Cambridge Scholars Publishing, 2024-10) Sekoai, Patrick T; Sebogodi, Kelebogile; Gbadeyan, Oluwatoyin J; Chunilall, Viren; Gbadeyan, Oluwatoyin J; Sekoai, Patrick; Chunilall, VirenThe continual increase in global population and the high level of industrialization have led to a large food waste output to the point where natural reclamation pathways have become overloaded by this crisis. Furthermore, the consequences of food waste can no longer be ignored, as it poses severe hazards to the environment and humans, and a high capital expenditure is required for its treatment. Therefore, there is a need for the development of cheap and environmentally conscious processes. Secondgeneration feedstocks will advance circular bioeconomy practices by enabling the sustainable production of high-value-added products. The valorization of food waste to high-value-added products has garnered considerable attention in the scientific literature, and it is seen as an Valorization of Food Waste to High Value-Added Products innovative strategy that will advance the circular bioeconomy. This chapter discusses the various market-based products that can be synthesized using food waste as a sustainable feedstock. Biobased products such as biofuels, biochemicals, biopolymers, biofertilizers, and volatile fatty acids are discussed in this chapter.Item Process techniques for conversion of lignocellulosic biomass to biogas(Cambridge Scholars Publishing, 2024-10) Sebogodi, Kelebogile; Sekoai, Patrick T; Chunilall, Viren; Gbadeyan, Oluwatoyin J; Sekoai, Patrick; Chunilall, VirenThe urgent need to combat climate change and establish sustainable energy sources has propelled biofuel research and development. Biogas production through anaerobic digestion is widely recognized as a pivotal solution to divert biomass waste from landfills, reduce environmental pollution, and provide a carbon-neutral energy source for humanity. Secondgeneration feedstocks, specifically lignocellulosic biomass waste from the agricultural, forest, and timber industries, have emerged as the optimal alternative to foster economic growth without jeopardizing food security or misusing arable land. However, their intrinsic resistance hampers the complete extraction of their fermentable sugars, necessitating the exploration of diverse methods to facilitate the easy access of sugars for hydrolysis. Hence, this chapter delves into various lignocellulosic biomass pretreatment techniques employed to optimize easy access to fermentable sugars for valorization in biogas production.Item New source of biogenic silicon from sugarcane bagasse(Springer Nature, 2024-11) Seroka, Ntalane S; Khotseng, LThis paper describes the generation of biogenic silicon from sugarcane bagasse ash (SCBA). Furthermore, silica was recovered from sugarcane waste using a modified thermochemical approach, that is, tetrapropylammonium hydroxide, and then reacted with magnesium in the magnesiothermic reduction process to produce biogenic silicon. The physicochemical properties of the produced nanocrystalline silicon were examined using Powder XRD (P’XRD), Raman spectroscopy, FTIR, TEM, and SEM. X-ray diffraction spectroscopy revealed a peak at 2θ of 28 corresponding to a 30 nm crystallite size. The Raman analysis revealed a pronounced peak at 510 cm−1, indicating highly ordered silicon. The surface analysis revealed two distinct bands at 445 cm−1 and 1046 cm−1, representing the Si-O rocking and Si-O-Si stretching behavior. Nanotechnology as an enabler has proved that SCBA as a sustainable and renewable resource can be used for the production of biogenic silicon.Item Characterisation of additive manufactured Ti6Al4V-W–Ni composite(Cham: Springer, 2024-11) Mahamood, RM; Akinlabi, S; Jen, TC; Pityana, Sisa L; Omoniyi, P; Arthur, Nana KK; Akinlabi, ET; Da Silva, LFMExcellent properties of titanium alloy grade V make this alloy a material of choice in aerospace industry and other industries such as biomedical and medical industries. The most attractive of these properties for the aerospace industry is the high-strength-to-weight ratio. The need for advanced materials that are designed to produce a set of properties that cannot be seen in a single material is constantly needed in various engineering applications. Additive manufacturing (Am) technology is central to achieving this goal because of the possibility of producing any component using the desired material in a single manufacturing run and as a single component no matter the complexity of the part. In this study, the microstructural evolution and mechanical property of Ti6Al4V-W–Ni composite produced through laser metal deposition, an additive manufacturing technology, was investigated. Elemental powder of nickel and tungsten powder were deposited on titanium alloy grade V substrate by varying the laser scanning speed from 0.12 m/mm to 0.48 m/min, while keeping all other processing parameters constant. The effect of scanning speed on the evolved microstructure and microhardness were studied. Functionally gradient microstructures were observed in all the samples with varying microhardness values. As the scanning speed was reduced, high microhardness was observed. All samples produced have higher microhardness values than the substrate material. Samples produced at a scanning speed of 0.3 m/min has the highest average microhardness value of 491.8. This study revealed that AM can be used to produce complex part with designed material properties in a single manufacturing run.Item Remediation of marine pollutants for biorefinery innovations(Springer, 2024-10) Khoaele, KK; Mphahlele, IJ; Gbadeyan, OJ; Sithole, B; Chunilall, Viren; Aransiola, Sesan Abiodun; Bamisaye, Abayomi; Abioye, Olabisi Peter; Maddela, Naga RajuThe exponential growth of plastic production and consumption worldwide has been a growing concern for environmentalists. Mismanaged waste plastic significantly contributes to marine pollution, which can have severe environmental implications. To fully understand the environmental impact of plastics throughout their lifecycle, it is essential to identify their sources, pathways, and removal during remediation. Plastic waste harms marine species, threatening their survival and affecting the food chain. The ingestion of plastic waste is the primary way marine animals are affected. However, the consumption of waste plastic by “invader” species and the absorption of chemical additives from ingested plastics are lesser-known threats. This can help determine the adverse effects of waste plastic on overall ecotoxicity. Recycling waste plastic to develop composites with naturally sourced fiber as reinforcement is another measure for reducing resources and remediating the environment. This practice has increased the demand for waste plastic biocomposite for various applications in various industries, helping reduce waste and lessen environmental outcomes. This chapter focuses on integrating marine waste plastic into value-added products using biorefinery innovation.Item Carbon-metal sulfide nanomaterial photocatalysts for environmental remediation(Elsevier, 2024) Hlekelele, Lerato; Mdlalosem, Lindani M; Nomadolo, Elizabeth N; Mtibe, Asanda; Chauke, Vongani; Makgwane, Peter R; Kumar, NaveenThe combination of transition metals and sulfides creates a class of elite semiconductor materials that are capable of forming important electrochemical reactions under reasonable conditions. These electrochemical reactions have been shown to be beneficial in environmental remediation and other applications. Some metal sulfides have been shown to have an edge over metal oxides, including their narrow band gaps and their sulfur edges with lone pairs which is suitable for photocatalytic reactions. However, metal sulfides have problems associated with photocorrosion and the short lifetime span of the photogenerated charge carriers. There are various ways scientists have implemented to increase the viability of metal sulfides as photocatalysts, in particular, using carbonaceous materials. The formation of hybrid heterostructures between metal sulfides and carbonaceous materials (graphitic carbon nitride) is one of the most studied methods of increasing the separation of charge carriers. The most studied types of heterostructures are Type-I, Type-II, and the p-n junctions, all with their advantages and disadvantages. Characterization techniques such as photoluminescence and transient photocurrent are usually used to demonstrate the usefulness of forming these types of heterojunctions. Apart from the formation of heterojunctions is compositing metal sulfides with conducting carbonaceous materials that do not have a band gap. In this instance, the carbon nanomaterials act as sinks for the photoinduced electrons. In this regard, different types of carbon nanomaterials have been shown to effectively increase the lifespan of the electron and hole pairs including carbon nanotubes, carbon nanofibers, graphene oxide (GO), reduced GO, and biochar, among others.Item The climate change landscape for rural Southern Africa(Springer Nature, 2024-12) Mateyisi, Mohau J; Nangombe, SS; Maoela, MA; Chenzi, V; Matsa, M; Chapungu, L; Nhamo, GThis chapter examines the landscape of climate change in rural Southern Africa (African land south of the equator), especially the climate characteristics in connection with rural livelihood patterns. The main challenge that propelled this study is the need for more literature on climate change focusing on rural Southern Africa. This knowledge gap not only complicates our understanding of how climate change affects the region and how rural populations adapt to these changes but also hampers the development of effective adaptation strategies. Within this chapter, attention is directed towards five distinct climate patterns in Southern Africa. South-East Africa, Central Africa, West Southern Africa, East Southern Africa and Madagascar. Although these regions boast varying biodiversity, environmental concerns, temperatures and rainfall patterns, each exhibits distinct impacts of climate change with the same probability of amplifying vulnerabilities among their respective populations. The study highlights that with projected changes in temperature and precipitation patterns in these regions, resilience efforts should pay attention to the vulnerabilities that are characteristic of rural areas. By analysing established trends and anticipated climate change patterns, research lays the foundations for assessing risk and vulnerability, paving the way for adaptation strategies that can support the livelihoods and economic activities of rural Southern Africa.